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1. l l l O Plumtre Parallel Server eet Corporate Peta r 5 ServietEngine Gadget i Portal Engine 1 JSP based Gadget A MPPE Web Service A Pi l M inf xs l Underlying layers HW and OS aes l l l 1 NICE a Eum l l l a MM First usage ofl i E d GadgetA 1 l l o i GadgetA MM No Preferences Stored p 3 PROPER HU l No Parameters I l No Preferences L l Show Preferences Screen a Preferences Screen instead l GadgtA I of Gadget A Parameters to Gadget A I Send along using Parameters l l l Preferences l yee el l Show Gadget A a ee ee Send along Store Preferences l r Prefere nces I HTTP Headers to Portal Server _ Store Preferences in l System Database l r 1 Onevery I jJ Gadge Gadget A consecutive H Fetch Preferences l use l Send along using Preferences l Preferences Craen I p a HTTPHeades Show Gadget A V I l Gadget A Figure 32 The Stages in Plumtree s Central Gadget Preferences Storage Handling Plumtree lists several benefits that arise from this architecture Amongst these are e Scalability The parallel portal engine is able to handle multiple gadget servers for one gadget web service distributing the load On the other hand multiple light gadget web services re
2. Comms API Portlets le i Portlet B z code pO jis Logical Server running on Single or Clustered Physical Server Logical Server running on Single or Clustered Physical Server Figure 36 Parallel two tier rendering as used in the Plumtree Parallel Portal Engine The two portlets Portlet A and Portlet B are executed simultaneously 94 Modular Development Frameworks for Corporate Portals a Literature Review It is worth to notice that the two solutions employing this method are the same two solutions that use the two tier approach to rendering explained in the preceding section 8 1 5 Portlet Caching By enabling a portlet to state that its content has not changed since the last execution one could relieve the server from executing portlets at all by caching and reusing the content from each invocation This is what most portals are doing A portlet may be cached at multiple levels Some portlets are showing the same content to all users of the portal other portlets content are coupled to a group of users while other still are tied to each individual user The caching mechanism enables the portlets to control at which level their content could be cached and to control for how long the caching should occur More on caching from the developers point of view is found in Chapter 11 Framework Features 8
3. Syndicated Gadgets This is a mechanism for delivering content to other portals or to systems that are not portals This syndication feature enables administrators to output content either as XML or HTML on a scheduled basis This enables easy exchange of content between for example business partners or customers User Profile The portal server keeps a profile for each user The profile includes which communities the user are a member of which MyPages he have created and the layout of these and the preferences for each portlet These preferences are communicated to the Gadget Web Services when the user requests rendering of the workbench containing the portlet This process is described under Architectural Features Preferences Plumtree supports different layers of preferences Plumtree states In fact Plumtree supports five layers of preferences Plumtree C but does not define these five layers in detail Apparently some of these are set by the portal administrator to define such properties as which physical server the enterprise application resides and credentials for how to connect to this resource Other preferences are from the user tailoring his specific view of the gadget to suit his needs The last category mentioned are the community preferences which are specific for community gadgets These are not user configurable but are instead configured for the whole community as a whole 7 6 3 Software Quality Model Referen
4. 10 3 Portal Creation Before a portal solution can be used the portal system must be installed and the actual portal must be defined created and configured Installation 1s usually facilitated by some wizard approach guiding the administrator through the necessary steps However the logical definition of a portal can be a daunting task with the portal workbenches portlets users groups access restrictions and so on needing to be defined This subchapter will treat the creation of the actual portal while Chapter 9 3 Administration and Delegation treated the administration of the portal 10 3 1 Multiple Portals within a Single Portal Server Several of the portal systems analyzed can contain multiple portals within one server The reasoning 1s that several large corporations would like to be able to dynamically create new portal initiatives on demand The different portals are accessible either as a path extensions to the URL for example http company com portalA and http company com portalB or as a 5 Santiago Gala s post about multidevice rendering http www mail archive com jetspeed list working dogs com msg05108 html Thomas Schaeck IBM s follow up http www mail archive com jetspeed list working dogs com msg05149 html 107 Modular Development Frameworks for Corporate Portals a Literature Review separate internet address for example http portalA company com and http portalB company
5. August 1999 http www oracle com oramag oracle 99 Jul 49ind html Accessed May 30 2002 Firestone Joseph M 1999 White Paper No Thirteen Defining the Enterprise Information Portal DKMS Executive Information Systems Inc 31 July 1999 http www dkms com EPIDEF html Accessed April 5 2002 Gates Lana 2001 The second portal wave Application Development Trends vol 8 no l Jan 2001 p 29 32 http www adtmag com article asp 1d 2669 Accessed June 4 2002 Grammer Jeff 2000 The Enterprise Knowledge Portal DM Review March 2000 http www dmreview com master sponsor cfm NavID 193 amp EdID 1940 Accessed June 4 2002 Hunter Jason 2000a The Problems with JSP Servlets com Jan 25 2000 http www servlets com soapbox problems jsp html Accessed June 4 2002 Hunter Jason 2002b Reactions to The Problems with JSP Servlets com Feb 10 2000 http www servlets com soapbox problems jsp reaction html Accessed June 4 2002 Luce Charles 2002 Three trends in enterprise information portals ZDNet Enterprise March 19 2002 http techupdate zdnet com techupdate stories main 0 14179 2855580 00 html Accessed June 5 2002 Margulius David L 2002 Plug and Play portlets InfoWorld April 26 2002 http www infoworld com articles fe xml 02 04 29 020429feportaltci xml Accessed June 3 2002 144 Modular Development Frameworks for Corporate Portals a Literature Review
6. Reliability Recoverability PVETIEL IA Understandability Learnability Quality in use Usability Operability Likability Time Behaviour Efficiency Resource Utilisation Analysability Changeability Maintainability Testability Adaptability Installability Portability Co existence Conformance Replaceability Figure 39 The ISO IEC 9261 1 Quality Model The grey boxes are sub characteristics that are deemed valuable for this thesis 136 Modular Development Frameworks for Corporate Portals a Literature Review Nevertheless the standard makes use of several internal characteristics in assessing a software product s quality in use These internal characteristics are valuable as guidelines for what to look for in the vendor analysis Figure 39 shows the entire quality model with the sub characteristics deemed valuable for this thesis 1n a grey color The definitions for these sub characteristics are then listed verbatim from the source ISO IEC 9261 1 Following afterwards 1s some comments to these characteristics and to the selection 14 1 Definitions These are the definitions used from the ISO IEC 9261 1 document 14 1 1 Functionality The capability of the software to provide functio
7. 3 2 Scope This thesis objective is to perform a review of available recent literature about modular development frameworks for corporate portals with the purpose of charting current and future trends in functionality provided by these types of frameworks MyYahoo is built upon technology from the company TIBCO Yahoo and TIBCO have co developed a portal system they call Yahoo Portal Solutions using the Yahoo PortalBuilder http enterprise yahoo com portal products The Netscape Netcenter solution was available as a hosted service the Custom Netcenter Hosted Service and later developed as a stand alone server in partnership with Sun This partnership used the iPlanet brand and their portal server was called iPlanet Portal Netscape was later acquired by America Online AOL Sun have recently March 17 2002 concluded its alliance agreement with AOL and their portal is now called Sun ONE Portal Server http wwws sun com software products portal srvr home portal html Modular Development Frameworks for Corporate Portals a Literature Review The intent with this commission was to give CoreTrek ideas and guidelines of where to focus further development of the Machete framework observing that no actual standard existed This would be done in an effort of trying to align the Machete portal server with such trends Somewhat unexpectedly several standardization efforts were initiated during the writing of this thesis As stan
8. 69 Modular Development Frameworks for Corporate Portals a Literature Review 7 4 3 Framework concepts Since the actual server implementation 1s not available and the available documentation 1s only the two documents already referred to it 1s a bit difficult to analyze the framework concepts For example the portal 1s probably using the administration module available with the WebSphere application server However some of these concepts are revealed from the API and these will be reviewed Multiple Pages The workbenches referred to in this API is called pages The portlets are placed on pages and user and group persistent data is scoped to the level of a page There are two different types of pages user pages and group pages Configuration on multiple levels The portlets may be configured by the portlet developed using the servlet specification s normal deployment descriptor web xml Each portlet instance is also configured in the portal specific deployment descriptor portlet xml In addition there are two run time configuration possibilities This is explored in detail in the next section Portlet Modes and States The portlet registers support for different modes for example help and edit This 1s configured in the portlet deployment descriptor The portal server then displays icons for these modes and invokes the respective mode switching action on the portlet if the user clicks on any of these A portlet on
9. BEA A WebLogic Portal Datasheet no date file portal ds pdf BEA B BEA WebLogic Portal Architectural Overview Version 4 0 October 2001 http edocs bea com wlp docs40 pdf architec pdf Accessed June 4 2002 BEA C BEA WebLogic Portal 4 0 Getting Started with Portals and Portlets Version 4 0 March 2002 http edocs bea com wlp docs40 pdf portal pdf Accessed June 4 2002 BEA D WebLogic Portal Personalization and Interaction Management Datasheet no date file wlp pers intmgmt ds pfd BEA E WebLogic Portal Integration Services Datasheet no date file wlp int sves ds pdf 147 Modular Development Frameworks for Corporate Portals a Literature Review 16 3 3 Epicentric Epicentric s documents can be found at the Epicentric Resource Library http www epicentric com solutions resource_library jsp Registration 1s necessary to gain access to most white papers Epi A Scalability and Capacity Planning Overview no date file epi wp EFSScalability pdf Epi B Epicentric Foundation Server 4 0 What s New no date file EFS 4 0 whatsnew pdf Epi C Enterprise Portal Management Systems The Next Generation Model for Business Portals no date file epi whitepaper EPMS pdf Epi D Epicentric Foundation Builder no date file efb pdf 16 3 4 IBM IBM s portal specific documentation is available at portal library http www ibm com software webservers portal library
10. However the idea behind getContent is simple yet powerful This enables the portlet developer to generate the content in any way he feels fit For example the developer may choose to use a template language to render the content Or he may choose to send the parameters further to a second server for rendering of the content there This opens for the use of an entirely different programming languages on a different platform for example PHP ASP or similar technologies This 1s along the same lines of thought that Plumtree uses in their portal system confer the Plumtree analysis in a later section The portlets can get hold of its PortletConfig object providing runtime configuration parameters This enables as mentioned the use of the same portlet code in multiple portlets For example a generic portlet for fetching news sources may be configured with the URL where the headlines are found and which news exchange protocol this site 1s using XML Configurations and Reuse of Portlet Code The portlet developer must define and configure the portlets controls and controllers in the Registry The registry is a set of XML files ending with xreg A portlet entry contains the following elements e Classname the java file that ultimately implements the Porlet interface e Parameters which are accessible through the PortletConfig object e Meta info containing description for the porlet The ECS s homepage http jakarta ap
11. IBM A Portlet Development Guide Working with the Portlet API 1 1 April 2 2002 file V41PortletDevelopmentGuide pdf IBM B Portlet Migration Guide Second Edition April 22 2002 file V41PortletMigrationGuide pdf IBM C Portlet API first draft author Stephan Hesmer Stefan Hepper Thomas Schaeck from IBM added to CVS repository for Jetspeed December 25 2001 http cvs apache org viewcvs cgi checkout jakarta jetspeed proposals portletA PI PortletA PIDraft pdf rev 1 amp content type application pdf Accessed June 4 2002 16 3 5 Oracle Oracle s documentation is available from the Oracle Technology Network at http otn oracle com Some documents require registration for access Oracle A Oracle 91AS An Oracle White Paper January 2002 file 9ias twp pdf Oracle B J2EE and Microsoft NET An Oracle White Paper April 2002 file JAEEandNET wp pdf Oracle C Oracle91AS Portal Release 2 Technical Overview An Oracle White Paper April 2002 file PORTAL V2 TWP FINAL pdf 148 Modular Development Frameworks for Corporate Portals a Literature Review Oracle D Oracle91 Application Server Java2 Enterprise Edition Facilities and Design Considerations May 2001 file OC4J TWP pdf Oracle E Oracle91 Application Server Release 2 Data Sheet December 2001 file 91appserver ds pdf 16 3 6 Plumtree Most of the Plumtree documents used are available at the following web si
12. Messerschmidt Leon 2001 Take the fast track to text generation JavaWorld July 2001 http www javaworld com javaworld jw 07 2001 jw 0727 templates p2 html Accessed June 4 2002 McDonough Brian 2001 The Enterprise Information Portal KMWorld vol 10 no 10 Nov Dec 2001 http www kmworld com publications magazine index cfm action readarticle amp Artic le ID 1124 amp Publication D 58 Accessed May 30 2002 Schroeder John 1999 Enterprise Portals A New Busines Intelligence Paradigm DM Review Sept 1999 http www dmreview com master cfm NavID 198 amp EdID 1371 Accessed June 4 2002 Shilakes Christopher C and Tylman Julie 1998 Enterprise Information Portals Merrill Lynch amp Co Research Report Nov 16 1998 http www e global es 017 017 merril entreprise pdf Accessed June 4 2002 Stevens Jon and the Velocity Team 2002 You make the decision Velocity http jakarta apache org velocity ymtd ymtd html Accessed June 4 2002 Vizard Michael 2002 Beware of portals you can t leave InfoWorld Vol 24 No 8 Feb 25 2002 p 8 http www intoworld com articles op xml 02 02 25 020225opnoise xml Accessed May 30 2002 Waters John K 2000 Portal Wars Application Development Trends vol 7 no 9 Sept 2000 p 43 47 http www adtmag com article asp id 2653 Accessed June 4 2002 White Colin 2001 The evolution of the e business portal DM Review vol 11 no 8 Aug 2001 p 22
13. The data is said to be time variant meaning that information about when an event occurred 1s stored The value of all these steps is that the data can at this point be aggregated along different axes or dimensions For example the number of purchases may be plotted against either time place product group customer income or some other dimension This can uncover valuable information that previously was unknown to the organization The term decision support hes along the same lines Business intelligence is used to facilitate decision making by giving the user an overview of the totality of the data available in the corporation Every aspect of the business decision processes from long term strategies to short term decisions may benefit from having numbers reports and statistics from the enterprise s different information sources readily accessible Schroeder 1999 points out that only a small fraction of users so called power users and the IT administrators themselves have benefited from the many business intelligence projects that have executed He argues that around 95 percent of the typical users in an organization either lacks access to these analytical tools or lack the expertise to use them Such reports and tools should therefore be made accessible in the portal preferably at different user levels from numbers and simple reports that are one click accessible to tools where the user needs to
14. Users Groups Permissions and Roless n ihr caida dee DE Ete AAs calor ME 29 3 979 IMCS SOMO ies ox tia ee ee E 30 S4 Portal C ate SOTIZAllODS ects osetia a cesarean aab am ds 30 6 Corporate Portal Framework Vendor Analysis eeee 33 6 Thedeeddora Portal Bramesvork s pe eat ih iecore reo tua aee eroe tra Perd 33 0 2 3X eIndob clec Molsa nO setae ande as So dtes ier weer a ED ou 33 AME EI Dto TERME 35 T WANG Viens ses RS l 37 7 Apache Software Foundation Jakarta Jetspeed ssss 3T 7 1 1 Architecture and Architectural Features ccccccccccccccccccecceeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeees 39 TOI Shami w Or CONGEDI Sedis aoo Qupd nt eate tap uad dun e e tad tes Ta oot oi duse add 42 Wal Prane work fe3bultes sue a E UD Dr od uU Qut aeu Sect UND Den oap ub quts aqu Sect NN Dua dus 44 7 1 4 Software Quality Model Referentes ecenin aane aa a NR 47 T2 BEA WebLogic Portalean a anne 48 7 2 1 Architecture and Architectural Features otc oa o M ORE NI pa eds 49 12 2 JBrdmewolkccolce DIS So diente edt Mb n aite di M e aiv tbi MR 54 723 Framework Ieabute S oessa aia vans cacao oatisats eaa tasa od ativan tpe eap 58 TL24 Software Quality Model References cues ses octo e t b ea pt aed Diete ts 59 7 3 Epicentric Epicentric Foundation Server sisse 60 7331 Architecture and Architectural Features eoe t vm ie de e s 60 132 Fram
15. gained from projects and activities in the past in addition to the sum of knowledge from each individual in the corporation Since corporate portals are such a focal point of the organization this would make a good place to put such knowledge facilitating applications and tools Knowledge Base A knowledge base 1s a system where largely unstructured documents articles and data are entered as knowledge articles along with keywords and often an abstract of the content Users can query the system for information by a searching interface usually rather advanced One can often select which parts of the article that should emphasized during the search e g title keywords abstract and full text search Searching algorithms may also be intelligent utilizing various heuristics about the articles for example by giving different weight to search term occurrences in the different parts of the article Articles may also refer to or link with other articles and new articles may supersede old articles In this way the use of keywords categories and links ties the articles together and consequently embodies the structure that makes knowledge out of information Grammer 2000 The 7 R s of Information Management Butcher and Rowley 1998 attempts to define the knowledge processing within an organization with a conceptual cycle shown in Figure 4 The figure is a composition of both the information cycle and the input and output for each stage in th
16. 1n the system permissions also called capabilities are used to control access to different functions within the system s applications Roles are assigned to users and a user might have several roles For example a portal system could be configured to have amongst others the roles sales manager sales representative and employee All employees in the corporation are assigned the employee role while all employees that functions as sales representative are given the sales representative role and finally are all employees that functions as sales managers given the sales manager role Further a role 1s constructed by putting together a set of capabilities To continue the example a sales application might have amongst others the permissions authorize contracts create contract and view contracts These permissions are assigned by the portal administrator to the different roles mentioned above The role sales manager is assigned all these permissions sales representative is assigned the two 29 Modular Development Frameworks for Corporate Portals a Literature Review last ones while the role employee is assigned the single permission view contracts These two different concepts ACLs and permissions roles overlap to some degree In several ways it refers to two different approaches to restricting access From one side a type of objects can require a specific permission to be work
17. 2 Platform and Language 8 2 1 Dominant Language and Platform Java and J2EE All analyzed portal frameworks except one 1s using Java as their implementation platform More specifically the Java 2 Enterprise Edition is employed to some degree from full utilization of all of J2EE s features to a dependency only on the Servlets part of the J2EE specifications The technology stack for these J2EE based systems is similar to the one shown in Figure 37 Java Virtual Machine JVM Operating System HardWare Figure 37 Technology stack for J2EE based portals Plumtree have made a portal server based on some compiled language it is only available for the Microsoft and Solaris platform However Plumtree also provides a Gadget Development Kit GDK for the Java platform Gadgets are Plumtree s name for portlets _ 95 Modular Development Frameworks for Corporate Portals a Literature Review One major benefit resulting from the use of the Java platform is platform independency Java Virtual Machines exists for most operating systems Several OSes have multiple JVM implementations several of which are free Multiple Open Source Java Servlet Containers are available in addition to a fully fledged Java 2 Enterprise Edition environment This makes the platform very flexible and a systems administrators and developers may decide whether they would like to use commercially developed and supported operating systems virtual m
18. All the ASF s software 1s Open Source licensed with one of the least restrictive open source licenses in use The ASF is definitely most known for their web server which is the most used web server in the world This web server was previously known simply as Apache but this term is now reserved for the software foundation itself and the web server has been renamed to Apache Web Server or commonly Apache httpd The Jakarta Project is one of ASF s projects This project s mission is the creation and maintenance of commercial quality open source server side solutions for the Java Platform based on software licensed to the Foundation for distribution at no charge to the public Their most visible product is the Tomcat set of Servlet containers although Jakarta has several other popular products Tomcat 3 x and Tomcat 4 0 are in fact the reference implementation for the Java Servlets specification 2 2 and 2 3 respectively A subproject beneath the Jakarta project is the Jetspeed Enterprise Information Portal The project started in 1999 The scope soon expanded somewhat and it became apparent that the system was heading towards being a general engine for web applications Discussions on mail lists arose and the Turbine project was spawned Turbine is now a web application framework that is being used by several projects including Jetspeed E http www apache org foundation faq html P Netcraft perform a monthly
19. As long as there are no standard these vendors will more likely develop portalifications of their own products instead of developing application integration portlets that could be embedded within any standard portal This will continue until either a monopolist 1s emerging as has happened with the desktop operating system market where the Microsoft OS is a de facto standard or a common adhered standard emerge 12 1 2 Java based Portlet API Initiated shortly after this thesis was begun the emergence of a Java portlet API standardization was unavoidable Java seems to have a definitive market share on the application server market and many of the portal vendors are already dedicated to the Java 2 Enterprise Edition platform The standardization process is called Java Specification Request 168 JSR 168 This standard s description is The Portlet specification will define a Portlet API that provides means for aggregating several content sources and applications front ends It will also address how the security and personalization is handled The need of the Java community that will be addressed is This specification will establish a standard API for creating Portlets thus avoiding locking in Portal developers in a specific implementation and allowing Portlets developers to reach a wider audience while reducing their development efforts The Java API standardization process is described in some detail in the analysis of the
20. Campbell s opener as ragged England hold on for a 1 1 draw Amazon com Search EU pushes for Mid East conference The European Union foreign policy chief Javier Solana urges Middle East rivals to create the right Search All Products climate for peace talks in two months F Cronje s body retrieved Keywords Q E Investigators probe the plane crash which killed the former South African cricket zi J s amazoncom captain as his body is retrieved BB C ANSYS Personalized Financial Times Regional News Customize jy Symbol separate by space or comma Symbol Look Up Done but with errors on page Internet Figure 27 Screenshot from Oracle Portal from MyOracle Oracle 7 5 1 Architecture and Architectural Features Oracle 91AS Portal is built upon the Oracle 91 Application Server s core services Oracle C and is itself a service The integration is complete as the portal service is an integral part of the application server The portal server is available for both the Oracle 91A S Standard and Enterprise Edition In addition to the application server the portal also requires the Oracle 91 Database Figure 28 shows the architecture of the portal Browser Clients Middle Tier s Database Tier Oracle9i Application Server Oracle9z le9 AS Web Cache Portal _ Repository Database Provider s mod plsgl Parallel Page Engine Oracle HTTP 9 Web Provider s
21. Foundation Server Epicentric have started a standardization effort called Web Services User Interface WSUI Version 1 0 Working Draft was released February 11 2002 and is accessible at the web site This has now been presented to the Oasis WSIA and WSRP committees as presentation documents Technical Description The idea behind the Web Services for Remote Portals are that the portal server merely instantiates portlet proxies for the remote portlets and configures these to contact the appropriate URL IBM WSRP WSRP When a user puts a web service portlet on his desktop an instance of the portlet 1s created on the remote side along with an optional session In return the portlet proxy get a handle to the remote instance with which it refers to this remote portlet instance When the user removes the portlet from his workbench the instance and session 1s destroyed on the remote portlet server State and preferences may be stored on the portlet server as with the Oracle portal system However the portlet may also ask the portal server to keep state as with the Plumtree portal system The state 1s then serialized and sent back to the invoking portal server for storage When the portlet 1s invoked again the state 1s sent to the portlet server again confer the Plumtree analysis The portlet can also use a combination of these where some state 1s kept locally at the portlet server and some state 1s sent to the invoking portal server Whe
22. IBM portal Chapter 8 4 IBM WebSphere Portal It suffices to iterate that the standardization is in progress and that the schedule states that by December 2002 the portlet API should be finished and a reference implementation of the standard should be finished 122 Modular Development Frameworks for Corporate Portals a Literature Review 12 1 3 Web Services Portlets The Web Services concept has gotten considerable attention lately Several Web Services Portlet standard initiatives are currently underway all recently started Promising interoperability between different architectures and platforms a Web Services based portlet standard will give considerable leverage for the portal concept The following subsections will briefly explain the concept of web services and how web services portlets could work Web Services Web Services are defined by the World Wide Web Consortium W3C as A Web service is a software application identified by a URI whose interfaces and binding are capable of being defined described and discovered by XML artifacts and supports direct interactions with other software applications using XML based messages via internet based protocols The Web Services are a remote procedure call RPC protocol based on XML over HTTP It is using several protocols for discovery localization and description however the major protocol facilitating the actual communication 1s the Simple Object Access Pr
23. JSR for Java Portlet Specification which became JSR 167 JSR 167 Before any of the specification s review time had elapsed both JSRs were withdrawn on January 20 2002 A very short time after the JSR 168 Portlet Specification JSR 168 was created with IBM and Sun as the submitting members and with all information from the JSR 162 and JSR 167 combined into one submission This JSR s Review Ballot deadline was on February 11 most members of the Executive Committee for SE EE approved the ballot and none was against it The timeline set for the standardization process is rather short with Community Review in May Public Review 1n July Final Draft in October and implemented Test Compatibility Kit TCK and a Reference Implementation in December 2002 The reference implementation 1s supposed to be developed in an Open Source fashion at Apache lead by IBM IBM WebSphere Portal version4 1 On April 2 2002 IBM released their first edition of the Portlet Development Guide Working with the Portlet API 1 1 IBM A This is a document associated with the WebSphere Portal version 4 1 due to be released in May 2002 with general availability in June 2002 This document outlines a further developed Jetspeed API This API peculiarly is not present anywhere in the CVS repository for the Jetspeed project Nevertheless it is a very interesting API with a high level of functionality This document is written by St
24. Se Idea E dE 105 OO Jxemulte PorU 5 sss Sapte ca Gai oum M A LEM AMD M IE A EM LM UE ade Se 105 99 TnternationaltZadliOti eoi m e oam da dea eq Maud aida eis 105 9 10 Statistics and Business MITICS s doe sete dev deua maie iude dm uem 105 IO Eramewotk Dealufes uec ir onse o di ada D P Idi udi a P Ie Idi adhons 106 10 1 User Abstraction OD CCl ueneno tepoctisdtatlucha dap nese inris oda iata AR etg nitas 106 10 2 Multiple Markup Support and Client Capabilities sess 106 0 2 1 Multiple Markup Eaneuages SUppott o i a o REI ee 106 I10 2 2 C ent Capabilities iae ges ua EROE a a ase taeda ee 107 10 3 Portal TOQHOPlsetunenti tede dik ate tade ade Sad ee eto o iuto UE Its caeco TAL LAM EDU Dea La 107 10 3 1 Multiple Portals within a Single Portal Server sse 107 10 52 Poralia 0 6 aceites duro ermita etti dn macies 108 10 4 Poret C TOdIORD n cct Eaton NE COME coer cM MD LUE Me eC EU 109 TOT iD velopime Portlets using APIS queo e e ER DEO OR DE I T DII dn 109 104 2 Editor Based Portet Creatine S ero soli to e o ive a e bed totes 110 10 5 User Pores COMMUN C Oesia ose een e t or ee ee tees aere eU ode esae ass 111 T0 JPordet Output 10 U SEE er E eats a irme bii a 111 10 5 7 Input from User to Porille sairus iet deett e teo tpe te ntt heiter esta ttu desde 112 10 6 Messages Inter Process Communication usto tO eT iens ss medd 113 Modular Development Frameworks for Corporate Portals a L
25. WML for WAP devices while Plumtree also supports Palm PDAs and RIM Blackberry pagers Conformance As the portal server is a middle layer element it has several directions in which there might be standards to conform to server on which it runs the API which it provides and the way in which the system integrates towards enterprise applications All systems except Plumtree are written on the Java 2 Enterprise Edition platform Plumtree is written in some natively compiled language and is available only for the Microsoft and Solaris platforms However the portal systems delivered from vendors with existing J2EE systems all require the vendor s own J2EE system This can easily seem like some kind of vendor lock in tactic The Apache Jetspeed system does not require the full J2EE environment as it can run on a simple servlets container Epicentric 1s a dedicated portal vendor and does not have their own J2EE server This means that Epicentric must be run on another vendor s J2EE server and Epicentric conversely emphasizes the amount of different configurations on which their system can run The portlets should ideally be able to run on multiple vendors However there are still no standard for portlets There are several standardization efforts being worked on as of this moment these are described more thoroughly in Chapter 13 Portal Framework Evolvement Replaceability This 1s a characteristic not quite applicable to portal s
26. a character set for his client The portal server then converts the internal UNICODE representation to this character set before transmitting the content to the browser The locale also sets other cultural conventions such as date time and number formatting Still no information about how to program internationalized gadgets was found Invitations The portal has mechanisms to enroll users into the portal with specific security profiles and ready made homepages and workbench sets This is specifically designed for B2B and B2C settings The administrator may generate special URLs that generate an account instantly if followed This feature enables viral marketing of the portal to target audiences for example by sending out an email to the company s customers embedding a generated invitation link Hosted Gadgets These gadget web services are hosted separately from the customer s Plumtree installations It may serve multiple customers and may also allow customers to share Services 88 Modular Development Frameworks for Corporate Portals a Literature Review Network Search Using this feature a search may span multiple Plumtree installations across the Internet or corporate intranet In addition the search may span other searchable indexes external internet and private intranet search engines Plumtree has developed a platform independent system for developing search services using the Simple Object Access Protocol SOAP
27. a user s page may exist in three states normal maximized and minimized 7 4 4 Framework features As the API is too extensive to cover thoroughly here only an overview will be presented The full description of the API may be found in the Portlet Development Guide IBM A and the JavaDocs for this new API will most likely be available at IBM s website shortly Portlet The Portlet interface is an extension of the Servlet interface found in the Servlet API The relationship between the Servlet API the Portlet API and an independently developed portlet ThePortlet can be seen in the following relationship javax servlet Servlet Javax servlet http HttpServlet org apache jetspeed portlet Portlet org apache jetspeed portlet PortletAdapter com some company ThePortlet By extending the PortletAdapter class instead of implementing the Portlet interface one is alleviated of implementing every single method the Portlet interface describes In addition this is a common trick to enable the Portlet interface to evolve without the developers needing to change all their portlet code to include the new methods that the evolved Portlet interface describes 70 Modular Development Frameworks for Corporate Portals a Literature Review The servlet dependency requires that the portlet must be defined in two different deployment descriptors First it must be defined as a servlet so that the servlet conta
28. amp J Local intranet Figure 21 The Portal Management Tools viewed by the System Administrator thus showing all the portals in the enterprise application The delegation of rights is done using the Delegate Administration page shown in Figure 22 E Portal Management Delegate Administration Microsoft Internet Explorer File Edit View Favorites Tools Help Qsak x BOD JP Search p Favorites Meda O S O D 3 ab i Address http localhost 750 1 portalTools application namespace admin_portal amp origin choose_admin jsp amp event link edit_delegated_admin Portal Management Tools aa BEA WebLogic Portal Delegate Administration Portal Management Click checkboxes to specify the administrators privileges To grant a privilege click the associated Edit Portal Admins Grant checkbox If you grant Page Management and Portlet Management privileges you can also delegate the ability to set Entitlements on Pages and Portlets by checking the associated Entitlements checkboxes Click the Can Delegate checkbox for any privilege that you want this administrator to be able to delegate to other users Portal Administrator demopa1 Grant Can Delegate Can Set Entitlements User Management Portal Page Management Portlet Management Skins Management Figure 22 The Delegate Administration page Customization Customization refers to the process of letting an administrator for a group or the use
29. and documents It builds upon existing functionality in the server to basic workflows staging approval and expiration of content Search and Taxonomy The taxonomy and searching capabilities of Epicentric s Foundation Server comes as a module The system works in concert with XCM to organize and categorize 52 Modular Development Frameworks for Corporate Portals a Literature Review information assets and Web content in a secure repository The different elements of the taxonomy system are protected by the permissions systems and thus enable the administrator to delegate the creation and maintenance of its structure and content to selected users The taxonomy s directory like structure 1s populated with Cards These contain links and meta data that refer to documents on web servers and objects stored within the XCM structure The user may browse this structure as he would browse a file structure and access the objects and their metadata directly The searching facility is built upon the Inktomi Enterprise Search Engine It integrates with the taxonomy enabling user to search for objects based on their meta data and content Support for other search engines will be offered in the future Statistics and Business Metrics Epicentric s term Business Metrics 1s referring to statistics specifically tailored to measure the effectiveness of different portal sites The framework gives the administrators the possibility to develop thei
30. and the rest of the system management is available Stability A portal system should ideally handle that a malicious portal application was installed whose portlets tried in every way to make the system crash This is not the case in any of the tested system instead any portlet on all these systems can way to easily crash the entire system In addition they have access to the entire system The Apache Jetspeed system is 1n beta revisions as of this date and is not considered ready for production usage The BEA system is developed on BEA s existing well tested technology and should therefore be rather stable The rest of the systems are rather new technology and no information about their stability 1s available Testability The modular nature of a portal system should enable modular testing where each unit is tested by itself verifying its function This 1s especially true for the IBM system where the stand alone portlet API could enable the development of a testing harness in which to run and test the portlets However overall the testability support was quite disappointing No system was found to have test bench systems for single portlets Oracle mentions some features in their developer environments but these have not been delved into The BEA system has access and timing statistics as mentioned under the Analysability section This can help as a first step in debugging a portlet 11 4 Portability Adaptability Ther
31. application s directory to another These files includes the resources making up the portlets e g JSPs Java class files graphics and HTML In addition the XML files making up resources as webflows and portlet configuration must be copied or regenerated using the EBCC However the Campaign and Commerce services are scoped within the enterprise application existing as enterprise java beans These are thus shared between all the web applications 7 2 2 Framework concepts Portal Administration The portal administration consists of managing the relationship between entities such as users user groups portlets skins and layouts The WebLogic Portal recognizes three types of administrators These are System Administrator SA Portal Administrator PA and Group Administrator GA System administrators which are members of the special SystemA dministrator group have access to manage all resources and thus all portal web applications within an enterprise application He may use a special web application within the portal enterprise application called WebLogic Portal Administration Tools portalTools to control all aspects of the different portal web applications This application s start page is shown in Figure 20 54 Modular Development Frameworks for Corporate Portals a Literature Review A WebLogic Portal Server Administration Tools Microsoft Internet Explorer Sele File Edit View BEA WebLogic Po
32. are frameworks connecting to a specific underlying enterprise application Plumtree mentions SAP R 3 PeopleSoft 8 and Siebel Sales The framework exposes a set of objects representing corresponding objects within the enterprise application Using these frameworks a developer is helped through the selection and assembling of portlets using a graphical wizard type step by step editor Benefits and Drawbacks Using a visual approach the vendor gives the developer some benefits First rapid portlet creation is achieved The user can generate a portlet within minutes or hours instead of days or weeks In addition the portlets are very similar making a uniform user experience The user can get used to how portlet are working and operating and all portlets developed within the same framework will look and operate in a similar way However there are drawbacks as well The developer is limited severely only being able to use the methods and functionality made available by the framework Anything outside of the scope of the tool is hard to do unless the framework have made provisions for the developer to use another development language on places where the framework is too restrictive So far the portal systems analyzed did not have such features 10 5 User Portlet Communication The portlet must at some point render its output and the portal must include this output in the correct place in the output stream In addition the portal server m
33. as an easy way to get a feel of the status of the server in addition to information on where to focus tuning and optimizing efforts Epicentric have a concept of business metrics referring to statistics tailored to measure the effectiveness of different portal sites The system comes with a set of metrics and the administrators may develop their own The installed metrics include static numbers like registered users pages and sites contained in the system Dynamic metrics include users using each portlet active users page views and minimum and maximum number of concurrent users 105 Modular Development Frameworks for Corporate Portals a Literature Review 10 Framework Features This chapter summarizes and discusses the framework features obtained from the preceding analyses Since the amounts of low level documentation available varied considerably from vendor to vendor some features may have been missed 10 1 User Abstraction Object Several of the portal system analyzed features some kind of user object This is an abstraction of the logged on user giving access to user specific properties and attributes For example the user object defined in the IBM API gives direct access to the user s full name nick name his user ID the last login time and a set of predefined attributes accessible via a getAttribute name method on the user object Apache Turbine s user object is fetched from the omnipresent RunData object A
34. both of the underlying frameworks are considerably intertwined This makes for tricky bug hunting as there is no clear distinction of where error sources may be located Changeability The software is changeable in every way since it is an open source product The entire product can be modified to the needs of the situation Used as is the framework is also very adaptable with many possible configurations Stability Apache Jetspeed is in beta revisions as of this date and is not considered ready for production usage In addition as low level features as the security model are still being revised and discussed This is not very promising regarding the stability of the code Adaptability The Apache Portal supports multiple markup languages specifically is WML for WAP devices supported by default Each portlet must specify which markup languages it support and then format its resulting output according to the connected device Conformance The Apache Turbine and Apache Jetspeed projects need a servlet container to run on and it does not need the full J2EE environment The portal does not require any specific vendor s servlet container and is developed to be standards compliant It is currently developed using the Tomcat 4 engine which is the reference implementation of the Servlet 2 3 standard but can run on any Servlet 2 2 standard compliant server too For Example New security proposal May 22 2002 http nagoya apache or
35. client and server or manages to take remote control of any intermediary routing point all information transmitted can be accessed without further effort However by employing the Secure Socket Layer SSL a high level of privacy is achieved This 97 Modular Development Frameworks for Corporate Portals a Literature Review layer enables security by encrypting the information transport between the browser and the server The resulting protocol HTTP over SSL is called HTTPS 5 2 8 Integrate the Extended Enterprise Usually four communities are referred to when talking of the extended enterprise First are the employees who are all the people that constitute the corporation The company s customers are the ones that pay for the goods or services thereby keeping the company alive and thriving Thirdly the company usually depends on suppliers in one way or the other Either the company needs products to resell or 1t needs equipment and tools in order to deliver products and services These three entities are usually referred to as the company s value chain Lastly a company often cooperates with partners 1n order to exchange products and favors Schroeder 1999 argues that a crucial feature of an enterprise portal is its ability to function on either side of the corporate firewall By enabling the corporations to open their portals administrative costs are reduced as the outside parties retrieves their own information The free
36. com Epicentric calls the different portals for portal sites and the collection of portal sites residing on one server a portal network Oracle refers to the portals as hosted portals and thinks of the collection as an ASP model The server administrator can delegate the administration of such portals to other users making them portal administrators or site administrators 10 3 2 Portal Creation Two different methods of creating portals are employed either using some graphical user interface generally an administration interface within the portal itself or with some direct file handling copying files or using a text editor to edit configuration files Visual Creation The different vendors have different approaches to creating portals Epicentric have elaborated considerably on how portals are created with their system thus this system is used as illustrations Epicentric apparently uses a web based graphical user interface integrated into the portal for all operations regarding the creation and administration of new portals e Site Creation Wizard Epicentric employs a wizard user interface to create a new portal site This is a short procedure consisting of naming a URL for where the portal should reside add workbenches add portlets to these workbenches applying a theme and then preview the site If the site looks good it can be deployed as a sixth and final step e Shared Components Shared components refer to components
37. description The entitlement editor is shown in Figure 24 and shows all the different conditions that may be imposed on an entitlement T e Modular Development Frameworks for Corporate Portals a Literature Review Select the conditions that will activate this action Conditions y The visitor has specific characteristics E The HTTP session has specific properties v An HTTP request has specific properties The date is Itis after a given date Itis after a given date and time r t is between two times _ tis between two dates tis between two date times Action click the underlined text to edit the values When all of these conditions apply the visitor has both ofthe following characteristics o Developer is equal to true SkillLevel is equal to High an HTTP request has both ofthe following properties Locale is equalto no NO o Character Encoding is equal ta 180 88581 1 itis between 8 00 00 AM and 4 00 00 PM UTC 02 00 hours Entitle the visitor as a NorwegianVVorkingHoursHighskilledDeveloper OK l Cancel Figure 24 The entitlement editor Using the portal s management editor the administrator can choose whether a portal page or a portlet can be viewed and whether it can be removed from the user s view by either granting denying or abstaining from altering the value of the right based on the user s entitlements The content of the por
38. eerte eiit t omatus toten tdi er he unis 132 12 5 Microso nt NE E iussai qoae ae o HO dte oua dtu isa dudas 132 12 3 7 Oh r Languages esaeonrevim ideam uicit duum uide duum 133 12 3 9 Nom browser Based Portals iust pte ita ub boton xdi eed Tata did udsgus 133 TSC OCIS ON Forreste eosar ain a OE N E tuia utei tassi etas hes tes ntu quiMu ae iu i ES 135 14 Appendix A Definitions used from ISO IEC 9261 1 cccccccccccccccceeeeeeeeeeeeeeeeeeeees 136 14 1 Definitions uoo aca M MM 137 I2 1 Punctionalttysie vv nbn in o inm e 137 PAZ Renabl V cx 5 a dstsestnerdcth cen SAntabslvestatanednadanndendGasneeheadaddlate te tectui N 137 14 15 Nia italia DIMEY euspen pedi qute 93 ua rptu alt ao C TR roe tet M abe as 137 DI PORO T ooseiesnte edite debuit dcr best deae fe tu ere best dde E Ntafurs 138 14 2 COMTE ES o ete Corm net weak One asi tis auc Ani oed iua og emo Uu OR c nce c tau aet moie 138 Is Appendix B Java 2 Enterprise Editio 2e DERI E p EP De 140 l6 Xppendix C References and ResoUFe Suse eto EEE bec ees 144 16 1 Papers INT CVC 82d esseri ia tease Reb iiia Dietas elec Musei a tena Diceret d 144 16 2 Oer RESOU ES rn anor eo ro meatu Ca ect anat sueta Eco 145 16 3 Vendor specific Documents and White Papers ccc0cceeesesseesessesssesesseeseeeeens 147 16 5 Apaches nec Gai euo tessa OR Ma EM ME ACE LM E M 147 OMNIS ET 147 163 JBDICCHILEIG ecd eie uet adum umma iuam ums 148 S MERI Tr Qe 148
39. employees of the corporation can be given user accounts on the corporate portal and can thus access the system from any location using any operating system on any device This means that applications that are installed on the corporate portal are accessible to all users at the same time Not only are installation costs reduced but reach is also increased Ordinary applications have to be developed or at least compiled for each operating system is should run on while a single installation is enough to reach the entire corporation when using a portlet application Easy Implementation Reduced Time to Market The standardization of the API and the technologies surrounding the WSRP standard will make the development of a portlet or a portlet application very easy A need in an organization can be satisfied very fast and the development can occur in any language if using the WSRP approach The time from an idea is conceived to the time a beta version is available to potentially all the user in the enterprise will be reduced considerably In addition the WSRP approach enables an unprecedented approach to application service providing If an organization wants to test or rent an application hosted with an ASP the only operation needed is to configure the portal system to include the WSRP URL Immediately the application 1s available to the organization s users Both these methods would obviously require the portal administrator to restrict how sho
40. enabling Enterprise Application Integration with Java A considerable amount of vendors has already made connectors for their applications and third parties are implementing connectors for other systems some portal vendors have already developed special connectors towards specific systems For example Plumtree have a set of Enterprise Class Gadget Suites which are pre made sets of portlets connecting to specific enterprise applications In addition Plumtree have made development frameworks for certain selected enterprise applications These are called Enterprise Class Gadget Frameworks The two tier rendering approach used by Oracle and Plumtree are interesting concerning interoperability Since portlets can be programmed in any language portlets can be programmed on the host system s technology instead of using the portal system s technology Security Java as a development platform is not as error prone to common security flaws like buffer overflows as many more low level languages are for example C and C The entire Java virtual machine s architecture is made for restricting a programmer s ability to code dangerously thus heightening the security level J2EE Connector Architecture products http java sun com j2ee connector products html Listing of application servers vendors EIS vendors and third party vendors 116 Modular Development Frameworks for Corporate Portals a Literature Review The portal systems
41. exchange of information is also vital to enable e commerce Each community have their own information requirements and charting these and making available the necessary information through the portal interface may help the corporation gain competitive advantage PortalsCommunity 2002 has made a review of which information needs each group has and what might be gained from sharing this information The following information 1s based upon this text Customers The main reasons for deploying a customer centric portal solution would be to raise the company s ability to acquire serve and retain customers In the current marketplace competitive advantage 1s becoming relatively more concerned with knowing the company s customers than with product features and innovation PortalsCommunity 2002 Customer intimacy relationships and service 1s paramount BEA BEA D E points out that customers these days demand that a corporation know who they are The customers have had contact with the corporation several times and repeatedly informed them of their different needs problems and their 1deas for solutions The customers therefore expect that the next customer representative they make contact with should know all the necessary information concerning these earlier encounters In a customer focused portal the users should be able to get information about products and prices check current inventory track current orders and delivery status place ne
42. existing data Internationalization and Localization The Epicentric Foundation Server is internationalized Portal sites may be deployed in any language The administrator defines which languages are available for the entire server in the Portal Command Center The language a user sees 1s decided based on the locale settings 1n their user profile The user may choose between the languages enabled by the administrator The components of the portal may be internationalized interactively using the Site Console In addition administrators may bulk update every translatable component of the portal by uploading a resource bundle containing all the language strings for one component for one language Export facilities for the resource bundles are present thus enabling a template resource bundle to be exported for translation outside of the portal system Localizable components include modules pages styles and user interface components The localizable components may be protected by permissions giving the appropriate group of people access to localize components to their respective language only Epicentric focuses a lot on the language aspect but mentions that the server in addition 1s able to handle dates and times and international character sets Caching API The Foundation Server has core support for caching of components The idea behind caching is that the content of some components may be non trivial to render requiring significant amo
43. gt The servlet container is defined as a sub component of the J2EE standard confer Appendix B OF Modular Development Frameworks for Corporate Portals a Literature Review In comparison the other portal systems provide their own stand alone API not related to the Java 2 Enterprise Edition The ones using a servlet container apparently just were programmed on the servlet platform by way of convenience as the servlet framework is considered by most Java enthusiasts as a mature and developed technology IBM s earlier portlet API had similarities with the Servlet API but this was more of a cosmetic similarity to help servlet programmers migrate to the new portlet paradigm The portal systems whose APIs do not depend on the any of the J2EE specifications could potentially be developed as stand alone servers without the requirement of a servlet container at all It is hard to decide how big benefit this really is though 8 3 Rendering The rendering of the portal page is another area where different approaches have been chosen by the different vendors Both the laying out of the portlets how the portlet 1s constructed and how the windows around the portlet s content 1s rendered 1s done in multiple ways 8 3 1 Layouts The portlet server must use some rendering mechanism to include the content from multiple portlets On the HTML based output systems HTML tables are being utilized to divide the workbench area into the correct pi
44. identical and in particular no system allows a portlet developed for one vendor s framework to be run in another vendor s framework Possibly the most promising observation in regard to future trends concerns the two main standardization efforts that have been initiated These efforts hold the potential of providing corporations with a novel type of architecture independent enterprise wide operating system in which portlets can be developed for a single standardized portal platform and thus be run on any vendor s portal system The installation of a portlet application on a corporation s portal will provide all of the corporation s employees with instant access to the application s features The development of complete independent portlet applications 1s likely to become a new industry This standardization process will not take place without complications however Many industry leading actors have already joined the efforts suggesting that a standard would gain wide spread adoption However Microsoft the leading desktop operating system vendor has chosen not to participate in any of the efforts thus potentially constituting a major obstacle to the corporate portal s potential of becoming the new corporate operating system Additionally doubts are raised regarding whether application server vendors really are interested in a complete standardization as this potentially would lessen their leverage in pushing their entire technol
45. is shown in Figure 21 A group administrator may create new group administrators and control the customization for the group portals he is assigned to again only if the administrator that created him gave him the necessary rights The customization includes which portal pages portlets layouts and skins that are visible available and mandatory Visible means that the portal page or portlet is default present available means that the user may customize it onto his workbench while mandatory speaks for itself He may also choose the default settings for all these parameters This 1s called group customization i lm Modular Development Frameworks for Corporate Portals a Literature Review E Portal Management Home Microsoft Internet Explorer DE Fie Edit View Favorites Tools Help w Address E http localhost 750 1 portalTools application namespace admin_main amp origin wips_home jsp amp event link portal home v Go ee P z 4 hea Portal Management Tools aa BEA WebLogic Portal Portal Management Home Portal Management To edit an existing group portal click its name in the list below To create a new group portal click the Create new group portal link for a portal application To delete a group portal click the trash can icon next to its name Available group portals based on stockportal GroupPortal1 Group1 a GroupPortal2 Group2 a Available group portals based on myportal
46. its current namespace and ID This is used to qualify attribute names JavaScript function names and global variables in the output of the particular portlet 7 4 5 Software Quality Model References Fault tolerance The IBM system suffers from the same problem as the BEA system in regard to fault tolerance 1f one portlet crashes during rendering the entire portal workbench might crash This stems from the method the portlets have to output their contents the portlet is given a direct handle to the output stream If the portlet writes half of its output and then crashes the resulting page might very well contain inconsistencies Changeability The stand alone API gives developers a clear and consistent way of making new portlets however it does not enable the developers to change anything regarding design and rendering of workbenches including the traditional theme support layout changes and similar concepts If the system provides for such features this 1s defined outside of the described API Testability A stand alone API makes testing of single units much easier Since the API is detached from the actual server implementation a special testing harness may implement it and in effect run the portlet The portlet can thus be tested for conformance with the API contract However IBM does not mention such a testing harness but the API detachment makes this possible Adaptability The IBM API includes a method for accessing localiz
47. live The server asks the provider which portlets it contains and these are immediately made available to the users of the portal possibly restricted by access rights set by the administrator 9 5 Services Some of the portal solutions analyzed provide for a concept of services which are by name locatable resources A service is registered with the portal server using the portal s configuration files The registration includes some 1d or name by which it may be located The portlet programmer can fetch the service or an object representing the service by invoking some globally accessible method for example getService id The id refers to the id by which the service registered If the server does not have the requested service registered it can raise an exception or just return null By encapsulating common portlet tasks services in effect provide a standardized extension mechanism of the portal s built in APIs Jetspeed for example by default provides several services 1n addition to the ones already provided by Turbine Jetspeed s underlying framework These includes a service to manage the groups and users a service to help portal developers cache the portlets contents and services to access the roles management and ACL systems IBM also provides the services concept and includes an interesting service called the credentials vault which was elaborated on in the security subchapter 9 6 Multiple Workbenches All portals s
48. not treated as documents as such and are merely referenced as footnotes throughout the analysis sections Methodology The collected documents and information were studied and the architecture architectural features framework features and framework concepts have been summarized for each vendor The software quality model from ISO IEC ISO IEC 9261 1 has been used during the analysis specifically the capability definitions listed NN Modular Development Frameworks for Corporate Portals a Literature Review in Appendix B This thesis definition of features and concepts does not match directly to any of the capability definitions in the software quality model hence it is used mostly as a guide to what to search for However if a vendor has any specialty that may be described with one of the capability definitions this 1s specified for that framework For example if a framework had any special provisions to enable the developers to test their new portlets this is noted under the testability capability In addition if a framework has any obvious negative features this is also noted throughout As this thesis is meant to be a literature review the analyses mainly relies upon the vendors own documents This is not deemed problematic as the intention is to get a general overview of features and concepts by exploring the ideas of other vendors of such frameworks and not to arrest the vendors for over advertising their
49. of portlets WYSIWYG and Wizards based tools Oracle have a long time experience with application development using forms and queries including their large Oracle Forms application This tool is tightly integrated with the Oracle Database leveraging the PL SQL language These tools also provide the ability to web enable such forms and place them into the PL SQL type of portlet provider Epicentric provides their Epicentric Foundation Builder This product lets business users create Epicentric modules Epicentric s equivalent of a Portlet The tool supplies several Wizard style step by step editors where a user is lead through the definition and creation of a portlet Forms can be built with visual tools letting the user add buttons and modify form properties Reports are created with a query tool Plumtree mentions briefly that they are developing a gadget framework for developing stand alone portlets not requiring any underlying data source These portlets would contain their own application logic and data storage 53 For more on the IBM stance read the analysis of IBM and Chapter 14 Portal Framework Evolvement which gives more details of how a standard Portlet API will affect the corporate portal business 110 Modular Development Frameworks for Corporate Portals a Literature Review Enterprise Application Specific Development Tools Plumtree supplies a set of Enterprise Class Gadget Frameworks These
50. pieces of code that 1s configured in the Turbine configuration file They are accessed in the code using the RunData object that is passed around to every method Querying this object for a service name returns the associated service 1f configured Portal Structure Markup Language PSML http jakarta apache org jetspeed site psml html 46 Modular Development Frameworks for Corporate Portals a Literature Review The template based portlets described earlier 1s using a template locator service to find and load the configured templates and a template rendering service specific to the template language to execute them A caching service provides functionality to the portlet developer to quickly develop programmatic caching behavior for the portlet There is also a rudimentary persistence service callable from portlets The portlets may store strings in a map keyed by strings By invoking the store method on this service the portlet may at a later login retrieve the same strings 7 1 4 Software Quality Model References Fault tolerance The use of the getContent portlet invocation principle enables the framework to confine errors If the portlet that 1s rendering its content crashes while preparing it the framework can instead abandon its content and display an error message However whether the Apache Jetspeed system actually does this is not known Analysability The software is not very documented and the portlet API and
51. portal has to be created and defined indeed the portlets must also come into existence at some point Most portals have a set of portlets bundled at least as examples In addition new portlets can usually be downloaded for free or bought at the vendor s websites However for portal frameworks a good and expressive way of creating new portlets must exist The different vendors have several approaches to the creation of new portlets Some will be presented here 10 4 1 Developing Portlets using APIs several vendors have defined some kind of API on which to develop new portlets By providing a good API the vendor let the developers use their programming skills to develop exactly what they want and not restricting the code logic in any way Stand alone vs Coupled API The different vendors have selected different levels of detachment of their API The current Apache Jetspeed API is very tightly connected to the framework virtually not distinguishing the API from the underlying platform on which it runs On the other 109 Modular Development Frameworks for Corporate Portals a Literature Review hand IBM has made a completely stand alone API with the intention of standardizing the APT As a Solution lying somewhat in between these two extremes the Plumtree and Oracle approach is to supply APIs physically detached from the implementation This 1s a result of their two tier approach to rendering of the workbench confer
52. portal server runs and handles the portlets and how the user actions are communicated to the portlets e Architectural features refer to the features of the vendor s selected architecture often features that are intrinsic of such architecture or that are rendered possible using such architecture For example whether the rendering of all the portlets comprising the workbench is done sequentially or in parallel and whether user groups are supported e Concepts or framework concepts refer to high level concepts of the framework For example user roles theme based presentation and multiple customizable workbenches This term does not include application specific or application related features like group calendar or discussion board e Framework features refer to the features of a development framework especially lower level programmatic and declarative design features and capabilities For example programmatic features like Java based portlet API and scheduled task dispatching design features like WYSIWYG menu creation or declarative features like portlet parameters declared using XML e Framework and portal framework means a development framework in which one builds a Portal This includes frameworks where one declaratively configures a portal and frameworks that are geared towards programmers where one can using APIs program new portlets or extend other features of the portal system A por
53. portlets are invoked This can be used to output some JavaScript code that should be accessible to all user portlet instances Finally the portlet may implement PortletTitleListener to enable the title to be dynamically changed based on some decision criterion The title could for example be tailored to whether the portlet showed a detailed or overview description of some customer or be changed according to which type of client that has connected Events system Window Action and Message events The Portlet API makes use of the event concept inherent in several of Java s APIs If a user clicks a button on the browser or submits a form or similar user activities that the portlet has registered actions with an ActionEvent is fired to the appropriate portlet notifying it of the occurred action If a user clicks on any window control button of the portlet window for example maximize the portlet gets a WindowEvent fired describing which type of window event that happened The sending of messages to other portlets is facilitated by using the send method available in the PortletContext This method enables the transportation of an object implementing the PortletMessage interface to another portlet The server passes the message by invocation of a MessageEvent on the receiving portlet 5 The Epoch is the beginning of time for a UNIX system and is defined to be midnight January 1 1970 UTC 270 Modular Development Framewor
54. recently by IBM Microsoft and Verisign IBM WS S MS WS S Portlet Development Kits WYSIWYG Portlet Creation As the standards emerge it will become viable for third parties to develop portlet development kits and studios All the large standard technologies like HTML ASP and JSP a vast set of development tools exists for example FrontPage from Microsoft and Macromedia s web development tools Such tools will definitely be made for the portlet technology if standards are agreed upon These tools will be made for both the portlet API and the web services portlets For the portlet API tools will emerge that helps developers in creating portlet and portlet applications in WYSIWYG environments as can be seen in the full screen HTML tools mentioned However an even larger potential are the web services portlets standardization as this will enable portlets to be written in any language and hosted on any portlet platform Some portal vendors already provide wizard driven and visual style portlet editors confer Chapter 10 4 2 Editor Based Portlet Creation however there are currently no third party tools facilitating such portlet development 12 1 6 Potential Difficulties The standardization holds great promise for portal systems However not all analyses of the standardization conclude that the full potential will be achieved soon An article by David L Margulius 2002 points out that the corporate portal area 1s a bat
55. server and the portlets This helps a developer to isolate where errors occur as the invocations of the portlets methods are clearly defined The BEA system of recursive inclusion of multiple JSPs for each portlet and the workbench as a whole makes for tricky debugging If a erroneous element is discovered in the final workbench rendering it can prove difficult to find which JSP file that actually 1s responsible for that exact part of the markup language 118 Modular Development Frameworks for Corporate Portals a Literature Review Changeability Since the analyzed systems are frameworks their primary concerns are of course changeability The main idea is to let administrators and developers install configure and develop portlets Enterprise Application Integration data source communication and user management is also crucial In addition most systems also let the look and feel of the system be changed by means of themes or skins The Apache Jetspeed system is open source and is therefore changeable in every way even the framework itself BEA s system is also quite open with most of the portal developed on the same vendor s J2EE server The JSP files are available as are the webflow comprising the portal s operations which means that it can be changed in most every way In contrast to these the IBM documentation currently available only concerns portlet development No information about themes system look and feel
56. some time CoreTrek realized that other companies had come up with the same idea Not only was the technology with which both MyYahoo and Netcenter was built upon available for hire but several new actors was emerging in the field This segment of the computer industry had even been defined and terms had been coined This foundation has been further developed and the Machete server as it was named has now been released in version 1 1 The portlets that populate the Workbenches in this framework are called Corelets A collection of Corelets which together form a functional unit is called a module The framework s focus has been application development and is not restricted to any specific underlying system It is Java based running on any Java based web application server and may interface with any database A Corelet API provides developers with the means to program new portlets and modules easily Several standard modules have been developed to enable a fast assembly of a new portal deployment Due to the lack of any existing official or de facto standards in the portal and portlet area CoreTrek have developed their portal and portlet API independently as have most other portal vendors CoreTrek have so far not been able to fully analyze the emerging technologies and trends in this field nor been able to do an analysis of where efforts have been focused by other vendors The hope 1s that this thesis will shed some light on these topics
57. space is essential work flow systems and other work related routines which support cooperative actions e g a shared project planning system In addition scheduling organizing negotiations making ad hoc decisions recovering from errors and assembling resources are actions that belong in the coordination space Communications are crucial also in this space 5 2 Remote Access Being built on the open protocols HTTP requiring nothing more than a web browser to access the system the corporate portal enables remote access Consultants sales people and companies with several branch offices are likely to benefit immensely from this type of access as accessing the corporate information system is just as easy from outside of the organization as from inside However a frequently noticed adverse effect results from the lower bandwidth and higher latency that can be present on remote access This negative effect is often insignificant though compared to the large upside such an access gives One can also compensate the bandwidth problem to a certain degree by using so called ow bandwidth themes when working from remote These are themes where images and the layout are cropped down to a minimum In addition security is a concern The web protocol HTTP is not secured meaning that all information is transmitted between the client and the server in clear text If a cracker can get physical access to any part of the communication path between the
58. study of the different vendors penetration in the web server market Their April 2002 study included more than 37 million sites and showed that over 56 is using the Apache Web Server http www netcraft com survey 14 As so many other names and terms in the software industry the name Apache server also has its history The name stems from the phrase A patchy server P httpd is a unix ism where many server processes called deamons have names ending with d HTTP is the protocol and the server process serving these requests thus gets the name httpd Other examples are nfsd fingerd talkd ftpd ntpd and sshd http jakarta apache org site mission html 17 http jakarta apache org jetspeed site index html 18 http jakarta apache org turbine index html m Modular Development Frameworks for Corporate Portals a Literature Review E http www bluesunrise com jetspeed portal template Home Microsoft Internet Explorer File Edit View Favorites Tools Help Qba x A f A seadh ye Favorites Media Address a http www bluesunrise com jetspeed portal template Home Jetspeed Welcome to Jetspeed Welcome Endre Stolsvi Customize HTML WML Edit account endre3 Logout Home A Documentation API Hello World in Velocity Symbol Price Change Volume If you want to change this text please enter it below 5 E m Hello World in Velocity Update Java Web Application Framework e Turbin
59. transformation mechanism to the different markup languages supported by the different clients However given the large span of screen sizes it would be very difficult to both fit everything into the small screens and at the same time make use of the large areas that web browsers on computers typically support This would probably require the device independent markup to include if like constructs regarding the screen size and device independence is in effect not gained In addition this device independent markup would have to be adjusted towards the lowest common denominator regarding the markup language s potential This would lead to the situation where no system s full capabilities would be utilized This has been discussed on the Jetspeed mailing lists in conjunction with the discussions about the new portlet API The systems supporting multiple markups lets the portlets know which client is hooked up so that the portlet may format its output according to the markup supported by the client 10 2 2 Client Capabilities The IBM system takes this approach further and makes available an object representing the client This object can be queried for which markup the client supports and if it supports multiple markups the developer will get a list in decreasing order of preference In addition the developer may ask what capabilities the client supports for example whether the client supports JavaScript frames tables and so on
60. webflow is of a complicated nature BEA C However the developer guides does indeed state that if the developers are well versed with webflows they can even customize this part of the portal Architecture of the portlets A portlet is a set of JSP files associated with some XML meta data The main parts of one portlet is shown in Figure 16 Determined by portal framework we Portlet 1 banner isp e header isp PLE eps gt partlet jsp E Footer jsp Em Saa NNI Figure 16 Main parts of a portlet filenames are local to the portlet1 portlet By clicking on the help icon the help jsp file is run and displayed in a disconnected browser window from BEA BJ These elements and several other attributes comprise a portlet definition Other elements include parameters like editable the user may edit the portlet the parameter is which JSP file should be shown in edit mode floatable the user may disconnect the portlet yet another JSP file and attributes like minimizable Only the titlebar is showing and maximizable using the entire work area and whether login is required The portlet jsp mentioned in the last subsection is responsible for invoking these various JSPs and taking into consideration the numerous attributes Portals as Web Applications When installing the WebLogic Portal several enterprise applications are installed as well One of these is the portal enterpri
61. 2 1 is called the Jetspeed API J2EE Application Server Requirement Most of the two APIs functionalities are the same However there 1s one major difference while the Jetspeed API were completely stand alone expecting a implementing server the so called Portlet Container to handle the life cycle of the portlets the IBM API defines a portlet to be an extension of a Servlet thus requiring a Servlet Container to handle the portlet instantiation and initiation The Jetspeed API had a concept of a Portal Application This was a set of portlets bundled with the deployment descriptions for the portlets into a single file Such Portlet Application Archives with the extension par could be dynamically loaded and unloaded into the portlet container by the administrator This has in the IBM API been replaced by the use of the J2EE concept Web Application This means that a portlet application is bundled as a Web Application Archive with the extension war The result of this is that if the basis of IBM s API is going to be the foundation for the Portlet API standard then a portal server cannot any longer be simply a servlet container but must be a full J2EE implementation Evolution In the Portlet Migration Guide IBM B the author explains the API s dependency on J2EE as being an evolution towards a standardization of the Portlet API Some highlights from this evolution are both more conformance towards t
62. 2 Columns NEW No Javascript Page not working correctly Try here Internet Figure 2 Selection box based configuration From MyYahoo the original web portal zx Modular Development Frameworks for Corporate Portals a Literature Review Another selection scheme shows the user a graphic representation of the workbench The moving about adding and removing of portlets is thus a more visual like experience This scheme is shown in Figure 3 E http www bluesunrise com jetspeed portal template Customize Microsoft Internet Explorer File Edit View Favorites Tools Help Q Bak ix 2 7 A seah p Favorites Meda Address amp http www bluesunrise com jetspeed portal template Customize J e t 9 g g d Welcome to Jetspeed Welcome Endre Stolsvik Customize HTML WML Edit account endre3 Logout Home Documentation HTML Layout Add portlet API Layout Two columns 50 50 v OK Colors orange red v OK HelloVelocity Stock Portfolio Jetspeed Apache News from Apache Week Mozilla latest headlines Save amp Apply Internet Figure 3 Graphical configuration of workbenches Apache Jetspeed EIP Most portal systems enable the user to operate with several workbenches switching between workbenches by clicking on their buttons or tabs The administrator of the system often have more control being able to specify whether users should be able to configure their own workbenches specify ma
63. 28 http www dmreview com master cfm NavID 193 amp EdID 3832 Accessed June 4 2002 White Martin 2000 Enterprise information portals The Electronic Library vol 18 no 5 2000 p 354 362 16 2 Other Resources IntranetFocus 2002 Portal Vendors author White Martin http www intranetfocus com Portals Portal Vendors portal vendors html Accessed March 14 2002 IBM Web Services Security IBM WS S Web Services Security IBM http www ibm com developerworks library ws secure Accessed June 4 2002 IBM WSRP IBM WSRP Web Services for Remote Portals IBM http www ibm com developerworks webservices library ws wsrp Accessed June 4 2002 2145 Modular Development Frameworks for Corporate Portals a Literature Review IBM WSXL IBM WSXL Web Services Experience Language IBM http www ibm com developerworks webservices library ws wsxl Accessed June 4 2002 IBM WSRP presentation IBM WSRP WSRP Web Services for Remote Portals IBM http www oasis open org committees wsrp presentations wsrp high level ppt Accessed June 4 2002 Microsoft Web Services Security MS WS S XML Web Services Security Microsoft http msdn microsoft com ws security Accessed June 4 2002 Java 2 Enterprise Edition J2EE Java 2 Platform Enterprise Edition Sun http java sun com j2ee Accessed June 4 2002 Java Specification Request 16 JSR 16 J2EE Connector Architecture Specification JCP Final Relea
64. 2EE products to vary widely and compete vigorously on various aspects of quality of service Products will provide different levels of performance scalability robustness availably and security However several other areas are of interest User Management The user system is left out of any standard Whether the user authentication and other features of the user 1s obtained from an LDAP source or from other sources are not mentioned The installation and administration of the authentication system may have different levels of user friendliness and features Groups roles and permissions will most probably be included in a standardization effort This must also be taken care of by either a disjoint system or included in the authentication system Portal Specific Variations It is important to remember that the standardization exclusively will deal with portlets and not the portal implementation The portlet API and the web services portlets will only standardize the actual portlet interfaces The technology running and containing the portlets are not influenced by this other than being required to support the interfaces defined in the standard Outside of the standard several areas exist where vendors can focus their attention 130 Modular Development Frameworks for Corporate Portals a Literature Review Firstly the architecture of the system will most probably be vastly different from vendor to vendor Some will includ
65. 9 2001 Final version Published International Standard of June 21 2001 available at http www 1so org iso en CatalogueDetailPage CatalogueDetail CSNUMBER 2274 9 Accessed May 24 2002 146 Modular Development Frameworks for Corporate Portals a Literature Review Web Services Component Model WSCM OASIS Web Services Component Model WSCM TC Oasis http www oasis open org committees wscm Accessed June 4 2002 superseded by WSIA Web Services Interactive Applications WSIA OASIS Web Services for Interactive Applications TC Oasis http www oasis open org committees wsia Accessed June 4 2002 formerly WSCM Web Services for Remote Portals WSRP OASIS Web Services for Remote Portals WSRP TC Oasis http www oasis open org committees wsrp Accessed June 4 2002 Web Services User Interface WSUI WSUI Delivering Application as Web Services Initiated by Epicentric http www wsui org Accessed June 4 2002 16 3 Vendor specific Documents and White Papers 16 3 1 Apache Jetspeed Apache Jetspeed s documentation 1s found on the Jetspeed website http jakarta apache org jetspeed Apache A Portlet Howto http www bluesunrise com jetspeed docs PortletHowTo htm Accessed May 12 2002 16 3 2 BEA BEA WebLogic Portal documentation is found on BEA s comprehensive documentation site http edocs bea com portal specific http edocs bea com wlp docs40 index htm No registration is necessary
66. Apache Jetspeed team for answering my questions my flat mate Per Kramer for support and finally Ine Vasshus for keeping my spirits up Sandnes June 5 2002 Endre Stolsvik Modular Development Frameworks for Corporate Portals a Literature Review 1 Summary This thesis investigates the functionality of current development frameworks for corporate portals a relatively new concept also known as enterprise information portals The main focus of the study is on areas concerning portals functional components their architecture and architectural features and frameworks concepts and features The thesis is based on a review of recent topic related articles and scientific literature in addition to analyses of six vendors corporate portal framework The analyses are based mainly on the vendors white papers framework documentation and technical documents However two of the portal systems have furthermore been subject to installation and testing and the test results serve as additional basis for analysis In essence the thesis is divided into four parts Part one constitutes a review of what corporate portals are what arguments are being used for their value what requirements they should fulfill and which functional components they usually provide This part is mainly based on the literature review The analyses of the portal framework solutions are presented in part two In part three the findings of the analyses are sum
67. As Margulius states it In other words we d get neater view into the same old bunch of silos Another problem that the portal industry faces 1s that the number one desktop operating system vendor Microsoft has not joined any of the portlet standardization efforts The reasons for this can seem obvious Sun and Microsoft have had several legal battles over the Java platform resulting in Microsoft s complete abandonment of the environment In addition IBM is in important positions in both standardization efforts thus linking the web services and Java standards more than desired by Microsoft IBM is in addition a long time Java supporter making the problem even bigger This fact can hamper the standardization efforts to a considerable degree Microsoft s complete control over the desktop environment means that whatever they decide upon will be very influential for the entire IT business With the release of the NET platform the company can potentially lead the customers and developers away from the platform agnostic concept of the corporate portal More on NET is found in Chapter 12 3 1 Microsoft NET 12 1 7 Vendor Diversification Given that standards appear a natural question 1s to ask how vendor will diversify and get business This question 1s especially interesting since there exists a free reference implementation of the portal system The J2EE 1 3 specification mentions this in Chapter J2EE 2 9 J2EE We expect J
68. Chapter 9 Architecture and Architectural Features The two tier approach severely complicates the interaction between the portal and the portlet but this 1s hidden behind the API However the two systems using this approach neither have any provisions for one portlet to communicate with another portlet or an explicit way for the portlet to communicate with the portal server Multiple Language APIs Another effect the two tier rendering approach 1s already mentioned but should be emphasized again the portlet implementation 1s separated from the portal implementation by way of a common standard protocol HTTP This implies that the programming language for the portlet is also disconnected and a portlet can be written in any language However the communications between the portal server and the server where the portlet 1s residing 1s rather complicated To hide these intricate exchanges the vendor supplies multiple portlet development kit or gadget development kit in Plumtree s case for several languages This kit provides an API for the developer to program new portlets Oracle supplies PDKs for Java their own proprietary PL SQL URL based portlets and Web Services based portlets while Plumtree are more geared towards much used web languages supplying GDKs for JavaServer Pages Java Servlets Microsoft s Active Server Pages and Perl 10 4 2 Editor Based Portlet Creation Several vendors have made some kind of visual creation
69. Existing vendors new market opportunities categorization explained in Chapter 5 4 Portal Categorizations BEA does not have any database server of their own and the selection of databases on which the system runs 1s therefore much wider Supported databases are IBM s DB2 Oracle Microsoft s SOL Server and Sybase In addition Cloudscape a pure Java RDBMS is shipped with the product This 1s primarily to be able to run the system without any other databases installed Overview The portal system provides a set of services These are tuned towards efficiently build launch and maintain high performance e business sites BEA B There are four main services e Portal services provide means for creating deploying and managing multiple enterprise portals targeted to the corporation s different user bases e Personalization services make the portal user experience tailored to each user s role and needs It delivers dynamic and personalized web content e Campaign services are provided to target advertising e mail and product discounts to specific audiences e Commerce services are building blocks and functions for e commerce for example shopping carts product catalogs transactions and order fulfillment Of these only the portal services are of interest while the other three are not integral to the portal architecture and its concepts and features They will be briefly mentioned throughout the analysis The WebLogic
70. Modular Development Frameworks for Corporate Portals A Literature Review Endre Stolsvik June 2002 i Portal My Pages Microsoft Intermet Explorer E A Ge pdt yew Fgexiee pos Hep i Oec O RA Aeh fries Gr Meda amp O GL EN LO of h Aies Gh piata plommitree com eertalimipage inpre asp eeriD 5 E6BOBPagelDa haad ye ei heces Mie fecha 45 32585 m bul Sa Wit cere Ta FLhumbinee ort t 1 if mer ns rr z ia nim A MY PAGES Document Search ENNNNNNEEEENENEN Search kptings Ac L el gtenr Ti IH ENDRE 5 OWN PAGE E BMY PAGES t DOMMIRITIEY LHOCUIME N TS WELCUHME SOLUIT EDNS PROCY AS ETTZICUTCIONENNEXJ eurowoathor ux weather maps Litle 5 Forecast weather for Europe L Select a Region from the Map Or From This List All Products w Go Choose a Ci Regen v Yahoo Search a v Ix Enait the botnet Lucus While Pages fa v Tx Firat Hame Last Hame required City Town State Rem Learn about ihe frange pou can do on the Flumtree Corporate Portal 3 My Panes c5 Communities UK Traffic fa ffs J f WaT Aun fiz WAF Reali AM POIT Iz A screenshot from the Plumtree Corporate Portal Acknowledgements I would like to thank my mentor M Letizia Jaccheri for guidance and comments throughout the semester my boss and mentor Eirik Rasmussen for reassurance during tough times Siw Gabrielsen for helping me out with my English Rapha l Luta and Glenn Golden from the
71. Portal Cache Figure 28 Oracle9iAS Portal Architecture From Oracle C O Modular Development Frameworks for Corporate Portals a Literature Review Throughout all their documentation Oracle 1s very anxious to explain that the portal exclusively is Built upon open internet standards Against these types of statements it is somewhat peculiar to note that the Oracle portal server requires both Oracle s application server with its host of services and Oracle s database thus completely locking the customers into Oracle s particular architecture Oracle 9i Application Server Oracle s Application Server product line is the Apache HTTPD Web Server extended with a set of mods The Apache server is modular in nature and all functionality except the raw delivery of files are facilitated by such mods Oracle supplies the following modules e mod fastcgi for persistent CGI processes e mod plsql for direct invocations of PL SQL procedures stored in the Oracle database mod oradav for distributed authoring and versioning support mod ossl for SSL security implemented by Oracle mod_osso for routing of Oracle91AS single sign on request mod oc4j for communication between the Apache processes and Oracles J2EE implementation OC4J OC4J Oracle91AS Containers for J2EE OC4J implements the Servlet Container and EJB Containers for the J2EE specification Oracle D Oracle frequently emphasizes that this 1s an ext
72. Portals a Literature Review Epicentric s favored term to emerge as the information silos still are unconnected To reach all information the users have to roam from site to site This is where the next generation portal solutions is needed Epicentric says that to implement an Enterprise Portal Management System one will need an enterprise wide portal platform standard This system will have to have integration capabilities that will unify a large set of different portal solutions such as IBM Plumtree SAP Lots Oracle and Microsoft Exchange Since Epicentric is the only portal vendor to provide the complete enterprise wide portal platform standard required for an Enterprise Portal Management System Epi C the solution is self apparent This white paper does not explicitly tell how this integration of portal deployments 1s to be done It still seems like the corporation is required to leave the earlier portal deployments behind and migrate them all to one installation of Epicentric s unified portal system Multi Level Delegated Administration A server administrator may create a set of portal sites for different business groups for example different departments or different entities in the extended enterprise The administrator can further grant administration rights to the different sites to the sites respective owners The server administrator may restrict the site administrators administrative capabili
73. Rather than giving a customer a username and a password to the seller s customer portal the customer can instead point their portal to the seller s web services portlet and thus integrate the seller s order forms and similar application directly into their own portal Other 128 Modular Development Frameworks for Corporate Portals a Literature Review possibilities are all type of applications that usually are hosted on a separate web site All examples of external resources given in Chapter 6 2 1 Make Information Accessible can be accessed via the portal as they were local resources significantly impacting the way that users do work This concept has been touted by Epicentric with their Modular Web Services However one major hindrance to the full utilization of this potential is the web service s current lack of security and authentication standards There is currently no common way that the seller can authenticate the customer or for the customer to authenticate the seller This still makes it necessary for the seller to issue some kind of credentials and for the portal administrator to configure the portlets with these credentials Oasis has initiated an effort to standardize web services security the Security Assertion Markup Language SAML This specification 1s soon to be released Java Specification 155 JSR 155 aims to implement this specification Another standard regarding this issue was initiated
74. Solutions and Baan with 1Baan Portal Existing vendors new market opportunities Several of the major IT and software companies are viewing the corporate portal concept as a new sales opportunity making frameworks which adapt their existing technology to the needs of the corporate portal paradigm Some examples are Oracle with Oracle 91AS Portal IBM with WebSphere Portal Microsoft with SharePoint Portal and Sybase with Sybase Enterprise Portal New entrants In addition to these existing companies new entrants have emerged with this new market They are mostly delivering frameworks instead of pre built solutions Some representatives are Plumtree with Plumtree Corporate Portal Epicentric with Epicentric Foundation Server Viador with Viador E Portal Infolmage with InfoImage Portal and Apache with the open source system Jetspeed EIP Companies with an existing background such as in the three first categories are essentially making their already existing applications available via the web browser utilizing the layout and making personalization features available with the portal paradigm Their products are often not made to be extended and they are monolithic in structure On the other hand they provide a good set of features as they all have a significant history in their respective sector The fourth category also has a background but 1s providing frameworks for building portals or interfacing with other portal frameworks D
75. Story http oracle com corporate index html story html 75 Modular Development Frameworks for Corporate Portals a Literature Review F Welcome to My Oracle Microsoft Internet Explorer File Edit View Favorites Tools Help Q Back x a f JO Search Favorites Media 4 N J 3 amp Address http my orade com servlet page pageid 47 49 amp dad moc amp schema MOC ZORACLE My Home Customize Mobile Help Oracle com Refresh Account Info Welcome STOLSVIK Sign Out Office Personal Endre s Own Tab Pages on My Oracle What s New on My Oracle Welcome to My Oracle New Features on My Oracle My Oracle Service FT com My Oracle Finance u Customized Financial Times News My Oracle Sales u amazon com My Oracle Marketing efau Search Amazon com My Oracle Human Resources My Oracle Projects Divine Business Libran My Oracle Procurement 1BIBIC a My Oracle Supply Chain BBC News My Oracle IT Manager Stock Quotes by Nasdaq com iil itil bit p India rules out Musharraf meeting Go Prime Minister Vajpayee says he will not hold talks with the Pakistani president during a regional summit as fears grow of a war over Kashmir Swiss setto legalise abortion Early results from a referendum show a large majority of Swiss are in favour of allowing women to have abortions in early pregnancy Launch Market Ticker NASBA Sweden hold drab England Niclas Alexandersson cancels out Sol
76. TR in 1911 At their website they state At IBM we strive to lead in the creation development and manufacture of the industry s most advanced information technologies including computer systems software networking systems storage devices and microelectronics IBM s 2001 numbers are enormous 319 876 employees and a revenue of 85 9 billion of which 7 7 billion were net income IBM is heavily involved in many areas of computer technology something that their Products and Services pages clearly indicate IBM is committed to the Java technology as well as several Open Source initiatives including Linux Several of IBM s technologies are for example Linux enabled including the Java based WebSphere platform IBM s WebSphere family of products includes a range of application servers several of which are J2EE compliant Amongst WebSphere s components is the IBM WebSphere Portal At the time of writing the version 2 1 of the WebSphere Portal Family is no longer being marketed and being replaced by the WebSphere Portal for Multiplatforms V4 1 This version is not available until May June thus complicating the review somewhat However technical information 1s already available at the portal website One of these documents is the Portlet Development Guide IBM A This guide in detail lays out the portlet API implemented in the portal server This portlet API has been influenced by discussions being held on the Ap
77. Thomas Schaeck and Stephan Hesmer In several aspects it can look like these IBM employees have run the entire Portal API development within IBM and used Jetspeed and its Open Source community to drive the discussions around and the development of this API New Jetspeed Portlet API proposal The 15 of November 2000 Thomas Schaeck put forth a document called Portlet API Requirements after some initial discussion on the Jetspeed list The first and most important requirement in this document is that the Portlet API should be self contained This would enable other vendors to implement the API without the heritage from Jetspeed and Turbine It would also enable a portlet written for one vendor s portal to be moved to another vendor s portal providing that both implemented the Portlet API Some time after around December 2000 the JavaDocs and the Java source code for the proposed API was added to the Jetspeed CVS archives by Ingo Schuster Thomas F Boehme authored most of this code and Stephan Hesmer did the rest During the next couple of months several discussions were held both at the Jetspeed mailing lists and at an IRC chat that were organized IBM gathered input from many people from several different companies during this process The set of documentation and sources were updated several times during these months mostly by IBM employees At about March 2001 the Jetspeed community the mailing list participants including p
78. XML This means that portlets for the Plumtree system may be developed using any HTTP aware platform it being Microsoft s ASP Macromedia s ColdFusion or the Open Source project Perl running via CGI or inside the Apache HTTPD web server Plumtree have developed code packages that enable rapid development cycles These are called gadget development kits and are currently available for Active Server Pages ASP Java ServerPages JSP Java Servlets Perl and mod_perl The preferences details for a gadget web service are supplied to the gadget server using HTTP headers The initial preferences configuration 1s initiated when the portlet notes that it doesn t get the preferences HTTP headers sent to it when it gets a request It therefore shows its configuration screen instead of the gadget content When the user replies the gadget web service sets up a set of variables and tells the portal server via the returning HTTP headers to store the preferences in the user s profile The next time the user requests the same portlet the server sends along the preferences variables to the gadget server The user may request to the gadget that it displays the configuration screen again giving new configuration details This process is shown in Figure 32 _ 84 Modular Development Frameworks for Corporate Portals a Literature Review Workbench r Massively
79. a whole into consideration and synergies from an enterprise wide collaboration platform can be reaped However this 1s an inflexible system where changes are very difficult to implement and new ideas cannot easily be implemented By having a system that enables developers to plug needed functionality easily into a common portal platform the corporation 1s enabled to fix business pain points rapidly and thus achieve a quick return of investments At the same time these components should be easily integrated into the corporation s total system giving long term gains for the whole organization This federated portal framework should provide for all the functional components mentioned in Chapter 5 3 Functional Components of the Corporate Portal or provide programming environments for developing such functionality easily Luce 2002 states that the expectations for portal platforms currently are being raised dramatically and portal platforms must now offer comprehensive architectures embracing all of the key areas of portal functionality integration categorization search publishing and distribution process collaboration personalization and presentation 6 2 Vendor Selection Most of the companies included in IntranetFocus 2002 comprehensive list of portal vendors are providing packaged solutions where the portal comes as a complete packaged product or are merely providing a portalization of their existin
80. aceholders or cards confer the Epicentric analysis These contain references to the actual item thus enabling any resource to be inserted into the taxonomy for categorization 5 3 2 Publishing and Content Document and File Management Content 1s the information in the portal itself Examples include articles news bulletins pictures and similar data that are displayed directly to the user normally using HTML It is different from documents in that content is usually displayed in the portal itself while documents are files that may be downloaded to the local machine and viewed and worked on there While some systems make use of a built in or portal specific management system other use and interface towards existing third party systems for example Interwoven and Documentum Epi B Plumtree B Content is usually managed and published into the portal using a publishing system White C 2001 This module is responsible for handling of everything that may be displayed within the portal There is often a publishing cycle which begins with authoring and contributing a document It 1s then reviewed and commented on by the author s peers or a dedicated reviewer When the content is approved for publication into the portal it is approved by a user with this capability After approval an editor will publish the content often with a start and end date The content might also be meant for just a group of users or for a set of users having a specif
81. ache Jetspeed mailing lists mainly from October 2000 to around March 2001 Screenshot is not available as the new version was not released at time of writing History of IBM http www ibm com ibm history 5 About IBM http www ibm com ibm us 34 IBM Products and Services http www ibm com products us 35 IBM s developer dedicated site http www ibm com developerworks WebSphere product family http www ibm com software websphere 37 WebSphere Portal http www ibm com software webservers portal 66 Modular Development Frameworks for Corporate Portals a Literature Review 1 4 1 Historical Review of the Portlet API To better understand the link between Apache Jetspeed and IBM WebSphere Portal and the shared Portlet API a historical review 1s required The information presented in this subsection is mostly obtained from the Jetspeed mailing list archives A couple of helpful persons still working on the Jetspeed project which were on this project at the time of these discussion have also given valuable information The Jetspeed project were started in 1999 confer the Jetspeed analysis Chapter 7 1 Apache Software Foundation Jakarta Jetspeed At the same time IBM had a portal system Early on several IBM employees joined the Jetspeed mailing lists and began to collaborate and contribute code to the Jetspeed project Of special interest are the names Ingo Schuster Thomas F Boehme
82. ache Velocity WebMacro inspired http jakarta apache org velocity Freemarker http freemarker sourceforge net Tea Disney Corporation Open Source http opensource go com Tea does Modular Development Frameworks for Corporate Portals a Literature Review different entities description of services user role definitions user authentication methods and so on e Declarative access restrictions enable the developers to make constraints on the different resources by querying whether a user is authenticated and 1f so whether he or she has the necessary privileges to use the resource This 1s declared within the deployment descriptor for the resource e Modular Development Frameworks for Corporate Portals a Literature Review 16 Appendix C References and Resources 16 1 Papers and Articles Detlor Brian 2000 The corporate portal as information infrastructure towards a framework for portal design International Journal of Information Management vol 20 no 2 April 2000 p 91 101 Dias Claudia 2001 Corporate Portals a literature review of a new concept in Information Management International Journal of Information Management vol 21 no 4 Aug 2001 p 269 287 DiBartolo Vincent 2001 Freemarker An open alternative to JSP JavaWorld Jan 2001 http www javaworld com jw 01 2001 jw 0119 freemarker html Accessed June 4 2002 Eckerson Wayne 1999 15 Rules for Enterprise Portals Oracle Magazine July
83. ache org ecs 45 Modular Development Frameworks for Corporate Portals a Literature Review e Role specifying which role the user must have to be able to view the portlet e Media a comma separated list of markups that this portlet can display e Hidden whether the portlet should be made available to users In addition there is a type parameter The value of this parameter is either instance ref or abstract An instance portlet is a directly defined portlet and should include all parameters necessary to instantiate a portlet from this configuration alone A ref portlet refers to a parent portlet overriding any parameters that are both set in the parent portlet and this definition of the portlet The parent portlet may also be a ref portlet thus enabling a chain of references ultimately ending in an instance or abstract portlet An abstract portlet is in effect the same as an instance portlet but this type cannot be instantiated by this configuration alone The only way to instantiate an abstract portlet is to refer to it via a ref portlet thus filling in the parameters necessary to configure the portlet This is in many aspects an object oriented approach to the definition of a portlet The ref type of portlet makes the defined portlet inherit the properties of its parents thus resembling the inheritance property of object oriented languages In addition reuse of code is also facilitated by th
84. achines and J2EE platforms or go for open source free solutions In addition combinations of these are possible as an example a corporation could decide to use the open source operating system Linux the free Java Virtual Machine from Sun Oracle s database and IBM s J2EE server on which the Epicentric Portal solution could run Commercially developed J2EE environments are often scalable thus being able to support a very large number of users An overview over the J2EE platform is given in Appendix B 8 2 2 Vendor Lock In One of the leading reasons for the J2EE standardization effort is to provide corporations with flexibility to choose between different systems when developing multi tier applications and enterprise services However it seems like several vendors use their portal product to leverage their own application server This 1s indeed also noted by Vizard 2002 in an article in InfoWorld Where a portal solution could have been developed on any conformant J2EE structure vendors with an existing application server platform have instead decided to require the use of their own application server Oracle goes so far as to require both the Oracle application server and database solution to use the Oracle Portal In addition choosing a vendor s application server opens the way to using a whole host of different add ons to this server each plugging especially easy into the vendor s own framework and poorly into any other framework In t
85. ame type of event system that the Java APIs are using Every action or event triggered by the user or the system can be picked up by the portlets by implementing the corresponding listener interface The methods defined in the interface are invoked when the specific event 1s fired providing the object representing the event as a parameter 112 Modular Development Frameworks for Corporate Portals a Literature Review Several types of events are defined WindowEvents are fired when the user clicks on a close minimize and similar buttons on the window frame to a portlet The MessageEvent is fired when portlet is sending a message to another portlet this will be explained further in the next subchapter By invoking the createURI method defined in the API the portlet can generate a special URL that will fire back to the portlet when the user activates it An ActionEvent is fired if the user clicks or otherwise invokes this special link 10 6 Messages Inter Process Communication The portal system from IBM seems to be the only one implementing explicit messaging between portlets Methods are provided in the API for sending objects from one portlet addressed to another portlet or optionally broadcast to all portlets on the active workbench The receiving portlet must on the workbench If there are several portlets with the same name as the one specified in the method invocation all of them get the message The message 1s del
86. an run on the same virtual machine A explanation of the NET platform is found in this Microsoft article Microsoft NET Framework Delivers the Platform for an Integrated Service Oriented Web http www microsoft com technet treeview default asp url TechNet itsolutions net evaluate netframe as sse Modular Development Frameworks for Corporate Portals a Literature Review currently about a dozen languages have been ported with several others on the way The languages can be intermixed letting a program developed in a language use objects from another language Even cross language inheritance is supported so that an object for example could be written in C subclassed in C and instantiated in Eiffel This environment and technology is being subjected to standardization through the ECMA standards body and is currently available for both the Microsoft and FreeBSD Unix platform the latter being a proof of concept port for the ECMA standardization An open source implementation of the INET development platform called Mono is underway This effort is trying to bring the NET platform to the various Unix platforms The NET framework is heavily geared towards Web Services Microsoft is a member of the Web Services Interoperability Organization and co developed several of the standards laying the ground for Web Services jointly with IBM and other industry leading vendors The emergence of a NET based portal se
87. and Business Portal are also used along with the more common Corporate Portal and Enterprise Portal NS Modular Development Frameworks for Corporate Portals a Literature Review 5 1 The Portal User Experience All portals share two concepts namely portlets and workbenches The terms are often different from product to product but these terms will be used throughout this thesis A portlet is a windowed box on the user s workbench The portal concept draws 1deas from the already familiar windowed user interfaces from modern operating systems while letting the user work in the familiar web browser interface A screenshot from a typical layout 1s shown in Figure 1 S Portal My Pages Microsoft internet Explorer e De dt wew Faites Toole nee Que BB fa Peet Pret ees O O a AD aa Adcress A hens iportal plumes Aum or usd imme m yug an Uer D 9 3 56 80 S age ID 24 LOS rand Type Choose be ehe 3259 3 oo Welcome To Phenviree Dori MY PAGES ENDRE S OWN PAGE CUEHPIUNTTIES E CU ERS WEELLLHME SELLE Ors M Eu SEARCH OUR SHOPS i 5 Forecast weather for Europe Select a R gion from thi Map Or From This Lest All Products a Choate a Ciy Rh agi n gt 7 nic Search T i E diu beter Virst Name Last Name required City Town Stat Leann about the things you can do on Plumtreg Corporate fon uk Trafic 5 My Paois 2 Communities a Fig
88. at are resource demanding The system can thus be scaled in a module oriented fashion However the portal server itself does not seem to be scalable and can thus become a system bottleneck 121 Modular Development Frameworks for Corporate Portals a Literature Review 12 Portal Framework Evolution This chapter will try to give some predictions about what is likely to occur in the corporate portal framework area in the next few years 12 1 Standardization Efforts The one definite prediction is the emergence of portal and portlet standards There are two areas where such standards are emerging namely for the Java programming language and for the Web Services set of protocols The first are exemplified by for example the IBM Java based Portlet API The other set are exemplified by the Oracle way of two tier rendering using SOAP XML as the transport language 12 1 1 Consequences for not having a standard As there is neither any monopoly nor any standard on the portal market companies will be reluctant to develop serious applications for portals thus hampering any progress in the portlet market A vendor might decide to develop an application or an enterprise integration application for one vendor s platform only to find that the chosen technology loose momentum just months after the application is finished This would render the invested time and resources worthless The same goes for the enterprise application vendors
89. ating system independence is achieved The browser is based on a defined standard HTML This standard 1s not owned by any corporation but is instead developed jointly by a multitude of vendors single persons and organizations Even other types of devices as PDAs and other handheld devices and television sets are getting a browser implementation embedded Several full fledged open source browser projects exist most notably the Mozilla browser This ensures that a standards compliant browser can be implemented for a specific hardware platform in a short time Client Device Independence Portal system standardization efforts are including multiple device support in their activities This will ensure that a corporate portal can be reached from anywhere anytime Server Architecture Independence The Java based portlet standard is inherently architecture independent as Java can run on most any platform However the web services based portlet standard makes for even more independence as both the portal server and portlets can be programmed in any language on any platform In this scenario the standard regards the interface between the portal server and the portlets thus enabling any standard web services portlet to be plugged into any standards compliant portal server The Mozilla Project http www mozilla org 131 Modular Development Frameworks for Corporate Portals a Literature Review Spans Entire Corporation All the
90. ationalization As mentioned the internationalization capabilities for the systems are not overly impressive BEA have two special JSP tags involving the internationalization These are the lt 118n localize gt tag used to define the language country variant and base bundle name to be used throughout a page and the il 8n getmessage tag used to access the specified resource bundle The IBM API only specifies a very rudimentary helper method for accessing text from localized resource bundles 10 10Caching As mentioned in Chapter 9 Architecture several of the frameworks have built in caching support However vendors have chosen different approaches to caching Plumtree 1s using a declarative approach where the administrator is configuring the caching behavior of the portlets Jetspeed is providing a caching service for the portlet developers to use reducing the implementation burden on the developer Epicentric provides a caching API which is letting the developer choose both how the portlet s content should be stored and by which keys the content should be cached Finally IBM is using a HTTP like programmatic approach having the portlet implement a getLastModified method This method should return the time at which the portlet s content was last modified thus enabling the portal server to decide 1f it has to actually run the content generating methods again or just use the cached information 115 Modular Develo
91. ay out the portlets in other patterns In addition the user 1s given considerable control over the layout of his workbenches On a workbench the user may choose to add a new set of workbenches selectable by tabs In this way a hierarchy of workbenches may be constructed 98 Modular Development Frameworks for Corporate Portals a Literature Review 8 3 2 Portlet Modes and Portlet Rendering The portlets are usually contained within windows that must be rendered by some mechanism In addition portlets may be displayed in several modes usually activated by clicking some button on the containing window frame The different action buttons on the window frame must be handled by some mechanism In Jetspeed the portlet window 1s handled by an object called a PortletControl This object contains a Portlet and is also itself a Portlet The portlet control both generates the output of the windowing markup and acts as the window manager for the containing portlet It controls in which mode the portlet should be shown being it minimized maximized or invisible and handles the actions that are done on the window All other methods are delegated to the contained portlet or portlet set In most other systems the portal engine handles the windowing and modes switching as base functionality The window markup generation is always changeable to enable themes support The BEA system have a very elaborate portlet rendering approach The develo
92. be an analytical expert to utilize them fully 5 2 4 Enter Data Enterprise Application Integration Not only would one want to make information accessible by extracting data from one or multiple data sources and applications within the corporation Being able to enter Resource site on data warehousing and related technologies http www dwinfocenter org index html 15 Modular Development Frameworks for Corporate Portals a Literature Review data into the different applications and systems conveniently integrated into the user s workspace is just as valuable This type of bidirectional integration is referred to as Enterprise Application Integration EAT Making a whole enterprise application available from inside the portal can be a daunting task however this is usually not necessary Some aspects of an application might be used much more frequently than other aspects and large parts of the staff might never even make use of major parts of the application due to restrictions to their role in the company Under such circumstances it would benefit the organization considerably if only these frequently used parts were made accessible through the portal In other cases parts of an application are used is used in a reduced manner where several fields and even whole tabs of a data entry forms is left out in the daily activities for most users In such cases making a simplified of the application accessible through the po
93. calNet http www verticalnet com and e commerce portals Business to consumer B2C e g Amazon ss ez Modular Development Frameworks for Corporate Portals a Literature Review http www amazon com are left out For a review of these categories consult PortalsCommunity s 2002 chapter Portal Definitions and Types of Portals Following is a categorization that will shed some light on the selection of frameworks done in the following vendor analysis This 1s the coming from where categorization which divides the different vendors into five groups depending on which business area they are coming from The categorization 1s adapted from Martin White 2000 Collaborative vendors These vendors have a strong background in the collaboration or group ware and document management sector Typical examples are Autonomy with Autonomy Portal in a Box Lotus with Lotus K Station and Verity with Verity Portal One Business Intelligence vendors These companies originate in the business intelligence reporting and data warehouse and marts sector Typical examples are Brio with Brio Portal Business Objects with Business Objects BI Portal Cognos with Upfront Portal and Hummingbird with Hummingbird EIP Enterprise Resource Planning Coming from the Enterprise Resource Planning sector several of the sector s leading actors have established a portal product Typical examples are SAP with MySAP PeopleSoft with PeopleSoft Portal
94. cept from Oracle also bundles several portlets in one package Portlet applications will enable portal administrators to install new applications into their portal much as an application can be installed on an ordinary operating system Services For the Java based Portlet API a standard way of extending the API by means of services seems like a logical addition The IBM API provides such functionality Dependency control Portlets portlet applications and services should be enabled to register that they provides certain features Other portlet applications can then define that they require or depend on such features this to assure that the installation of for example a given JSR 168 presentation for WSRP TC http www oasis open org committees wsrp presentations jsr168 wsrp presentation ppt Accessed June 4 2002 126 Modular Development Frameworks for Corporate Portals a Literature Review portlet application will succeed Such features are needed once multiple applications that possibly will communicate with each other can be installed and removed by merely clicking the mouse button Dependency control systems will warn an administrator that is trying to install an application that needs the features of another application that 1s not present or trying to remove a package that is needed by other still installed applications Such features are provided in most UNIX operating system for example the Redhat Package Ma
95. ces Interoperability Given the two tier rendering approach the Plumtree system may interoperate with every HTTP capable system This eliminates the need for technology bridges and 1s a considerable plus for the Plumtree portal See also Conformance In addition Plumtree have developed and are developing several Enterprise Class Gadget Suites which are complete sets of portlets ready to be installed and used Plumtree releases such suites for Microsoft Exchange Documentum Lotus Notes and Cognos e Applications Enterprise Class Gadget Frameworks are frameworks in which developers may easily create new portlets for specific enterprise applications Plumtree have released a framework for SAP R 3 and are currently developing frameworks for PeopleSoft 8 and Siebel Sales Security The Plumtree system states that due to the Internet Architecture which introduces a distinction between the portal server and the servers running the portlet the system 1s 89 Modular Development Frameworks for Corporate Portals a Literature Review more secure This system introduces another layer of protection as the portlet servers isolate the enterprise application from the portal server Fault tolerance Recoverability Availability If one portlet crashes only the portlet server on which it 1s residing 1s brought down The portal server locks this server out and uses any remaining servers with the same portlet If there are no avai
96. chronization It is still difficult to bring along internet access and a laptop everywhere This makes the Personal Digital Assistant indispensable to many business functions keeping track of the owner s meetings tasks and contacts The problem is that this will be yet another data registry with some meetings registered in the PDA and some in the portal s calendar This 1s where the synchronization enters as a viable alternative transferring the data back and forth between the PDA and the portal s database Changes in the PDA are copied to the portal and vice versa Different changes to the same record for example that a customer s address 1s changed on the PDA wile the customer is deleted on the server will have to be resolved manually A growing number of PDAs are becoming mobile networking appliances with internet access either directly embedded or via a mobile telephone This enables a PDA to access the portal and its data directly online Enabling access from PDAs can be achieved in different manners Applications can be built for the PDA that accesses the portal s data directly thereby enabling the access of certain data from a PDA Another way to integrate is at a higher level where the view of the data 1s tailored for some other viewing application other than a HTML based web browser e g the more minimalist WML browser on WAP capable devices At the highest level several new 27 Modular Development Frameworks for Corporate Po
97. d saving time might differ The files shared can be located in a central repository or can be attached to specific entities in the portal A contract document with a customer for a specific transaction can be attached to the customer s representation in the customer relationship management part of the system and the electronic copy of the user manual to some projector can be attached to the projector entity in the resources part of the portal By having a proper taxonomy one might be able to find a contract document both in the central directory and attached to the customer entity FrontPage Office Server Extensions http office microsoft com Assistance 2000 FPSEreqs aspx 20 Modular Development Frameworks for Corporate Portals a Literature Review File sharing systems is elaborated further on in Chapter 5 3 2 Publishing and Content Document and File Management Group Calendar A group calendar system will help the users organize and coordinate their daily activities Most people are familiar with some kind of electronic calendar which make it possible to enter view and edit one s day to day events and tasks Viewing 1s often possible in multiple fashions for example daily weekly monthly and annual view The purpose of the group calendar 1s to enable all the users of the system to share their calendars Users are for example able to view co workers and superiors calendars This enables a user to con
98. d State As mentioned in the previous subsection there are several levels where configurations and customizations may occur Initialization parameters are available using the PortletConfig object which is an extension to the ServletConfig object These parameters are global to all concrete portlets created out of this portlet while the PortletSettings object contains parameters specific to each concrete portlet As an example consider an administrator that has acquired a news fetcher portlet He makes one concrete portlet to fetch the headlines from BBC and another concrete portlet to fetch news summaries from the CNN site A list over supported new source formats and their supporting URL fetcher class files are contained in the PortletConfig object thus shared between both these two concrete portlets A group administrator places a concrete portlet on a group page This creates a concrete portlet instance and an associated PortletData object 1s instantiated The group administrator configures the concrete portlet instance of the BBC news portlet to display the news in terse format while the CNN instance should be displayed in full format with thumbnail picture These settings are stored in the PortletData object and are persistent Finally when a user actually views this page PortletSession objects are created These are used to keep the state of the portlet when the user clicks on the next ten or previous ten news articles buttons t
99. d standards as of version 1 3 A full low down of these specifications is beyond the scope of this thesis but a short description of some of the concepts within the Java 2 Enterprise Edition is elucidating Figure 41 shows an illustration of the scoping and relationships between the entities Figure 41 Scoping of entities in the JZEE specification e A Domain refers to one installation of a J2EE server and all the enterprise applications deployed within it This is a term used by BEA and is not a part of the J2EE standard 140 Modular Development Frameworks for Corporate Portals a Literature Review An Enterprise Application 1s a set of Web Applications and Enterprise Java Beans that are deployed inside a Java 2 Enterprise Edition compliant server The entire enterprise application may be contained within one single Java Archive a jar file whose ending is ear Web Applications are a set of JSP files Servlets Java code Java libraries and static content like images html files and other files These resources are accessible beneath a specific URL This can be either a domain for example http www corporation com or a path for example http www corporation com someApplication The web applications are run within the Web Container of the J2EE architecture A Web Container often called Servlet Container may exist by itself and does not require the full J2EE architecture set to run A
100. dardization 1s a very important juncture for a software vendor in any software market some effort has been directed towards determining what these standards implicate This has however left the author with a somewhat shifting scope The available scientific literature with corporate portals as the main subject is rather scarce However a considerable selection of articles from business and computer professionals magazines exists which combined with the scientific literature ensures that the background information 1s adequate The literature found revolves around the more high level aspects of a corporate portal what are corporate portals what requirements should they fulfill and what functional components do they usually offer Chapter 5 Corporate Portals Explained is mostly based on a review of this literature The thesis further charts what functionality a selection of development frameworks for corporate portals currently provide White papers data sheets programming information and other documentation from each of the selected vendors are studied and analyzed in Chapter 6 and 7 Two of the chosen frameworks was also installed The findings in each analyzed category 1s summarized and discussed in Chapters 8 through 11 Finally Chapter 12 will give some thoughts on how corporate portal frameworks will evolve Functionality 1s a wide term The reader should recognize that this thesis focus specifically 1s the development fram
101. dering All portlets on a workbench must at some point supply their content to the user There are two different approaches to how the invocation of the multiple portlets sitting on one page should be done The first 1s the obvious one of sequential rendering where each portlet is executed in turn their output being collected and sent to the user s browser However there is one big drawback to this Many portlets main task is to fetch information from underlying databases and systems thus each portlet may experience some amount of input output I O latency and wait time in addition to the actual CPU time it takes to execute the rendering Since each portlet 1s executed in sequence the total amount of rendering time ends up being the sum of these sub operations In this light the Plumtree solution is employing an interesting and actually rather obvious solution of parallelizing these tasks The Oracle documentation also talked of parallel at some point however it was difficult to deduce whether this was at the same level as Plumtree This method is shown in Figure 36 Comms API Portlets a a Comms QO TO I Portlet C code Portlet A code Workbench Portal ZEE Portlet A Portlet B Q NC A Co Workbench ee code x l Logical See running on Single or Clustered Physical Server
102. dition to the Web Services Remote Protocol WSRP will be explained more thoroughly in Chapter 12 Portal Framework Evolvement 9 9 Internationalization Most vendors boast that their systems are internationalized Oracle claims that their portal 1s localized to 27 languages and Epicentric mentions eight languages However it 1s obvious that internationalization has not been the primary focus for any of the portal vendors The focus if any is on language support and all vendors except from Epicentric seems to have forgotten about other internationalization problems like character sets text direction dates times numbers and currencies Epicentric mentions in one sentence that they support multiple character sets dates and times This 1s strange considering that the Java system and the HTML standard are internationalized to a remarkable degree tending to all the issues mentioned When both the vendors documentation have very little focus on this issue and the user abstraction objects analyzed does not have any attributes concerning localization an impression of pure neglect arises 9 10 Statistics and Business Metrics The BEA system features a set of developer centered statistics built into the J2EE server The system times each run of the JSPs and servlets in the system Displayed numbers are minimum maximum and mean run times in addition to the number of runs each resource have had These are invaluable to a developer
103. dressed Portals are useful for most people regardless of which culture they come from A user should be able to specify in which language he prefers his user interface and how dates times numbers and currencies should be formatted In addition his default currency and time zone should be selectable Such a setup would for example enable a Swedish salesman that is working for a Norwegian company and attending a conference in Californian to adjust his date time number and language preferences to Swedish his default currency to Norwegian while adjusting his schedules and other activities to the Californian time zone The APIs defined should include a vast amount of helper functions for such formatting as to make the coding of internationalized portlets convenient Security contained portlet applications The Java environment enables a java class file to be run in a so called security sandbox This could be implemented in the portlet APIs and pertaining definition files so that beta versions or distrusted portlet applications could be installed and tested without the risk of compromising the corporation s data A buggy portlet could potentially erase destroy and corrupt data and files from the underlying operating system and system database A malicious Trojan portlet could if left unchecked RPM website http www rpm org 127 Modular Development Frameworks for Corporate Portals a Literature Review wreak havoc on the en
104. e Turbine is a complete and flexible web An Open Source Enterprise application framework based on a model 2 1 Information Portal Jetspesd design o POWERE TDK The Turbine Development Kit allows you quickly e Jetspeed Home create your Turbine application Jetspeed is an open source portal system It supports multi device display capabilities a configurable portal templating system a portlet API for extending its capabilities and a simple Th tial f syndication system for aggregating remote e eSSeriua s resource for anyone nice running an Apache server or anyone Se a responsible for running Apache based Where you can find the complete documentation on Jetspeed and how to configure it Download the latest release e Under development This is where you can find the latest release of New 2 0 1 3 releases imminent ab performance the Jetspeed application testing e In the news Surveys show Apache still in the lead but little v ERN Wem 8D Internet Figure 6 Screenshot of a new user s view of Jetspeed EIP from demo site Bluesunrise The focus for the review will be the Jetspeed framework while Turbine s features will be examined when necessary for the understanding of Jetspeed The Jetspeed EIP project is at version 1 3a3 now 1 e in an alpha stadium of development Some time ago it was released as version 1 0 and later 1 1 but at some point the developers rethought their decisions and c
105. e up the portal page including banner title bars and the content The content of the portal page is decided by the state of the portal which is kept with the portal framework This 1s either one of a set of customization pages where the user chooses things like the layout of the portlets and which portal pages he wishes to have present or it is one of a set of layout files The layout file contains placeholders for the different columns of portlets These layout files may be two column three column and so on Developers may also make their own layout files including placeholders to let the portal system place the portlets The names and meta data about the portlets that should be placed in each column are fetched from the database The file portlet jsp 1s responsible for rendering the portlets unless the portlet is in its floating state in which case the 5 Modular Development Frameworks for Corporate Portals a Literature Review floated_portlet jsp takes care of the rendering The portlet jsp file is invoked repeatedly with different arguments once for each portlet in each column Every aspect of the portal presentation and functionality may be edited and tailored to the needs of the corporation Since the whole portal is merely made up of a set of JSP files graphics and a large webflow a developer may even choose to implement the portal from scratch Editing the portal webflow is not recommended as this
106. e 1s designed to integrate rather than replace customers existing technology Based on this Plumtree Software has sought to develop the most extensive partnerships in the industry They have Channel Partners being partners that deploy and roll out portals to customers and Technology Partners which are hardware and platform vendors as well as software companies that focus on a large set of business software Plumtree F Plumtree have over 300 customers and 61 of these are on the Fortune 500 list The customers combined the portal has five million licensed users About Plumtree http www plumtree com company 82 Modular Development Frameworks for Corporate Portals a Literature Review Z Portal My Pages Microsoft Internet Explorer Er File Edit View Favorites Tools Help Qs x z b JD sea K Faoites meda A S A D3 a S Address amp http portal plumtree com portal mypage mypage asp UserID 556808PageID 24104 amp WizardT ype Choose amp Refresh 0 4632685 v Go Welcome To Plumtree Portal Settings Logo Sunday June 02 2002 HELP uum Document Search I C ved ENDRE S OWN PAGE Search Options Advanced Network Sa gt MY PAGES gt COMMUNITIES DOCUMENTS WELCOME PRODUCTS 3 Plumtrec Search Amazon UK Cl EuroWeather Civ x UK Weather Maps Enix 5 Forecast weather for Europe Select a Region from the Map Or From This List Al
107. e applications A portal might also have some of these applications embedded as portal modules Email Email reading writing and archiving can be embedded as a module By accompanying this with an incoming email handling system two benefits can be realized First incoming emails can be automatically routed based on for instance the customer who sent it and secondly emails may be shared amongst several users For example an incoming email can be automatically linked to the correct customer based on a match between the email address of the sender and one of the contact persons listed with the company Simultaneously the sales representative for that customer 1s notified of this incoming email by some notification or alarm system If another sales representative or the sales manager checks up on this customer the email will already be attached and any replies that the first sales representative has sent are present Chat Messages and Discussion Forums In addition to the email system which originally was meant for long haul internet distance messaging three other communication systems or variants of emails are commonly used These are chat or instant messages messages and discussion boards All of these are excellent candidates for integration into or implementation on a portal system White M 2000 A short description of each type of communication form follows e Chat is an interactive type of communication between two
108. e are two areas in which these systems show adaptability internationalization and multiple device types The internationalization support is as mentioned disappointing While most systems state that they are fully internationalized the documentation revolves around languages Plumtree and Oracle s systems choose language based on the user s 119 Modular Development Frameworks for Corporate Portals a Literature Review browser setting while the Epicentric system have a locale setting 1n the user profile that the user may select Only Plumtree and Epicentric mentions anything besides languages and the elements mentioned are dates times and international character sets leaving out numbers currencies and text direction since the portal s Job 1s to make available a host of different internal data sources support for multiple markups would enhance its value as an information center several fold This has also been taken into consideration with at least the systems from Apache IBM and Plumtree All of these systems let the portlet take care of the formatting of the portlet s output while the portal takes care of making the workbench into some format that 1s appropriate to the markup language and device connected The reason for not trying to make some automatic conversion between markups or from a common markup is stated as the diversity of devices and the markup languages they support The most commonly supported markup is
109. e cycle _ Individual Organization _ External sources Resqurce o UN Bank Retrieval 1 Internal dources Relevant Restructuring Knowledge l l l Reading Knowledge l Domain Information Release l Recognition Validated l Knowledge Subjective I Knowledge l i l Reviewing Reintrepretation 2 e ncn Figure 4 The Information Management Cycle The 7 R s of Information Management Blue text is the input output for each stage of the process Adapted from D Buther and J Rowley 1998 Resource site on knowledge management and related topics http www brint com OrgLrng htm db Modular Development Frameworks for Corporate Portals a Literature Review Several of these stages can be facilitated by tools 1n the portal The search and retrieval of relevant knowledge 1s facilitated by searching functions in the knowledge base and other sources Reading and recognition are purely cognitive phases and can only be helped by the tools giving access to more relevant knowledge facilitating the recognition phases The reinterpretation 1s the process of converting the subjective knowledge into public knowledge for example by writing a document This can be assisted by effective word processing and document linkup facilities The reviewing phase consists of validating the public knowledge Knowledge systems can incorporate elements from the content management model to facilitate such reviewin
110. e fact that one java class file may be used in several instance or abstract portlets Included with the system are a set of standard portlets These portlets are supposed to be referenced by a ref portlet definition supplying the necessary parameters so that the portlet displays the correct URL template or news source A few examples FileServerPortlet simply includes a static configured URL XSLPortlet fetches a XML file and does a XSLT transform on it with the configured XML styles sheet RSSPortlet fetches a Rich Site Summary RSS file and formats the content to the desired markup either HTML or WML RSS 1s a format that enables for example news sites to export their current headlines There 1s also a similar portlet for the Open Content Syndication OCS format VelocityPortlet renders a Velocity template and displays the result JspPortlet executes a JSP file and displays the result PSML In addition to the Registry Markup the user s preferences the so called Site Markup are the two markup languages that makes up the Portal Structure Markup Language PSML The site markup is stored in separate XML files for each user These files includes information about which portlets are displayed on a given user s workbenches which layout is used what states the portlets are in and what skin is in use This is stored in a fashion similar to the hierarchy of portlets and panes that the user has configured Services services are locateable
111. e for J2EE application development Where do you go for true expertise on BEA technology Why not to the BEA technologists The BEA Developer Program leverages the knowledge among BEA s top engineers and SEs outto the developer community If you re looking for code samples alpha code enhancements to products utilities or other resources please join us IK Figure 13 Screenshot from the demo portal supplied with the trial version from test installation About BEA http www bea com about index shtml 48 Modular Development Frameworks for Corporate Portals a Literature Review 7 2 1 Architecture and Architectural Features Java 2 Enterprise Edition foundation The WebLogic Portal is built on Java technology and is designed for the Java 2 Enterprise Edition Nevertheless version 4 0 of the portal server requires the BEA WebLogic Server 6 1 with Service Pack 1 In fact BEA points out in the architectural overview that the portal 1s purely an extension of the WebLogic Server Where J2EE is designed for compatibility between the different vendors servers BEA has instead made their portal framework dependent on their own architecture This way of thinking 1s in stark contrast to other independent portal server vendors for example Epicentric which focuses on making their portal server capable of running on multiple vendors application server BEA is in every aspect a typical representative for the
112. e participants who may be the whole community or a selected group of users can all start a new message thread by posting a new message to the board or can reply to an existing message thereby doing a follow up on the thread Each board has some main topic of discussion and posting off topic messages 1s considered bad netiquette This type of system is yet another internet classic known as the USENET News System where each discussion forum has a hierarchical name denoting the topic of discussion and is known as news groups In addition to these very direct communication means other more implicit forms have positive effect on the collaboration possibilities for a group of users Some of these collaboration features is discussed below File Sharing A file sharing system enables users to upload and download files from the portal server This might be a specific upload download procedure requiring the user to download the file to some temporary location on his local disk work on it and then upload it Some operating systems and applications have special provisions for working on documents located on a web server notably Microsoft Windows running Microsoft s Office Suite The web server also needs some special software to handle this seamless integration With these requirements in place working with files from the portal server and working with files on the hard disk are very similar experiences where only the actual opening time an
113. e the portal as an integral part of the application server they already supply while others will produce it as an add on to such application servers The entire user interface will not be defined in any portlet standard A portlet s only requirement is that it is contained within a web page How that web page looks outside of this is entirely up to the portal implementer The way in which workbenches are laid out and how look and feel and theme support is implemented is also outside the scope of any portlet standardization This also implies that the workbench configuration interfaces will vary Finally service in general 1s an important point This not only relates to support personnel and agreements available but also to what additional applications toolkits portlet development features and documentation the different vendors supply 12 2Enterprise Operating System During the analyses an impression of the portal platform as an enterprise wide operating system has developed This might come more and more into focus as the portal standards mature In addition this system will be enabled to collate applications as portlets from multiple operating systems using the developing standard WSRP The benefits of using such a type of operating system are bountiful some are reviewed in the following sections Client System Independence As an ordinary web browser is used as the main interface between the user and the application oper
114. e user is explicitly mentioned This is true when both using the POST and GET methods of invocation The invoked URL must also provide the next screen either directly or by redirecting the browser to another URL However when in a portlet setting there might be multiple receivers For example one portlet might have an input box for quick searching through the internal document archive while the main portlet on the page is currently showing a form for entering a new customer In this setting there are two portlets of which one will be given the parameters If the new customer portlet gets the parameters for the search portlet it will probably choke understanding neither the parameter s name nor value Each vendor seems to have their individual approach to this however the basic thinking is the same Either an extra parameter is used to denote the id of the portlet that should receive the rest of the parameters or the URL 1s appended with some information that represents the id of the portlet that should receive the parameters Event Driven Programming By making a system for a portlet developer to make actions that the user fires the portlet may be developed like an event driven program This further strengthens the analogy with an operating system as most OSes lets their applications react to user events like mouse clicks and keyboard strokes in an the same fashion The IBM APIs have driven this approach to the fullest utilizing the s
115. eces A common way to do this 1s by dividing the screen into three columns with the two side columns being quite narrow and the one in the middle much wider The portlets are stacked on top of each other inside these columns and can thus be as tall as they like while the width 1s fixed However there 1s no reason why the portal developer could not control the layout system too This 1s tended to in the BEA and Apache Jetspeed systems On both these systems the developer have extended control of how the system lays out the portlets In the BEA system the developer configures the different layout within the system configuration files The JSP file responsible for the layout contains markers as to where the different portlets should be inserted In addition the developer tells the system how many columns there are in total and whether the portlets within each column should be stacked on top of each other in a vertical fashion or if they should be placed at the side of each other forming a horizontal column This information makes the system able to present a configuration screen to the users letting them place the portlets of their choice into the different columns The Jetspeed system uses a control called PortletController to render a PortletSet The controller lays out the set of portlets within the portlet set in a specific fashion The system is shipped with a whole set of controllers and the developer may develop new controllers that l
116. ectual endeavor Collaboration applications are definitely not portal specific Groupware or Computer Supported Cooperative Work CSCW applications have been around for quite some time Considering the access to large amounts of corporate data portals make an ideal place to work together A portal is suited for project planning and project work as the users may use the portal s information source to gather company documents and files Each participant of an ongoing customer project may go in and update his assigned tasks and statuses Uses may by the use of a discussion system post questions or answers and discuss the work with colleagues Records of communications with the customers and clients can all be archived with the project Moreover it does not matter whether the colleagues are located across the hall or at the other side of the globe Collaboration is an ambiguous term and tools that facilitate collaboration can be anything that enables any form of explicit or implicit communication between several individuals Several electronic collaboration systems might already be in use in an enterprise Gates 2001 points out that today people do most collaboration using email Other often used collaboration systems include communication by chat and instant messaging file sharing across distributed file systems and group calendar application The portal s job 1s to make these forms more accessible and to unify the access to several of thes
117. ed text from a resource bundle However the user properties object does not contain any attributes denoting which aA Modular Development Frameworks for Corporate Portals a Literature Review language the user prefers and the API does not contain any helper methods for localizing dates times number or currencies either The IBM API defines a Client object on which the portlet may query which markup or markup languages are supported In addition the client object can tell the portlet what capabilities the client support for example which level of HTML and JavaScript it can handle Conformance The IBM WebSphere Portal system specifically requires the IBM WebSphere J2EE server and thus does not conform to the J2EE standard However the IBM WebSphere J2EE server conforms to the J2EE standards thus being able to run components conforming to these standards IBM s Portlet API holds some promise of influencing the Java standard Portlet API to some degree This because the API has already been through some peer reviewing on the open Apache Jetspeed list and because it 1s very open in nature conforming to already existing standards for example J2EE In addition IBM 1s co spec leads for the standardization process thus might have some additional influence on the final specification However 20 different companies every one with their own ideas of how the final API should look are jointly developing the Portal API standard The fi
118. ed towards this same source Most often one or several of the company s data handling applications are also using this same authentication mechanism The same credentials used for the portal logon can therefore be used to log on to the underlying applications and systems If the credentials for portal access and the underlying systems access are different the portal can keep a repository for each user s credentials for each application that will be accessed When a user action inside the portal requires some access to the underlying application the application connects to the source via the portal s credentials repository The portal provides the system s authentication mechanism with the appropriate credentials and thereby simulates the actual user This facility 1s provided by the IBM framework 5 4 Portal Categorizations There are several categorizations of portal systems and many of the categories overlap considerably Martin White 2002 comments that there seems to be almost as many categorizations as there are consulting companies The term portal has been widely used and abused and there is currently a sizable set of different ideas of what the portal 1s As this thesis 1s about the concept of a corporate portal which 1s quite clearly defined by Shilakes and Tylman portal segments like the internet portals alternatively web and public portals e g MyYahoo and Yahoo itself vertical portals Business to business B2B e g Verti
119. ed with thus implicitly granting a user access based on this user having the specific permission On the other side the user can instead explicitly be granted the access via the object s ACL However the ACL approach provides for finer grained control as each object has its own ACL Together a user group and a role and capabilities system form a strong basis to control and restrict individual users access to data and functions of applications within the portal In addition properties of the user experience e g theme selection and internationalization might be pre selected or locked down for a group of users or for a set of users having the same role 5 3 9 Single Sign On One major appliance of portals 1s Enterprise Application Integration where information and selected features from underlying sources and applications are made available through the portal Most of these underlying systems require authentication of some sort usually still in the form of a username and password The portlets must thus impersonate users connecting to the underlying systems on behalf of the logged on user This would either require the user to supply the necessary credentials for each operation or let the portal store these credentials for the user applying some single sign on mechanism sometimes the company already has some main authentication mechanism in place e g a Kerberos system or a LDAP source The users portal access can then be authenticat
120. either already customers which have not identified themselves yet or may be viewed as potential customers The corporation can tend to both treating them as leads to possible sales Internet Strategy A well defined portal and internet strategy should tend to all these six communities Some portal systems can handle all of this using the same system This may give several benefits as this one system can just dish out information and access to applications based on the access restrictions on the specified piece of information or application system in accordance with the defined role of the user 10 Most of the sessionless tracking schemes assume that a repeated visit from the same IP address within a predefined time often 30 minutes is done by the same person This is not always correct though as multiple persons might be masqueraded as one IP address for example by sitting behind a corporate firewall Another way to track usage is by issuing a cookie to the user s browser or by URL rewriting which is a similar technique thereby establish a web server session for the user In this way one can track precisely what each user is viewing 1 However the needs and requirements of the customer and those of the business often vary The user would like to get everything within one easily locatable click The company might have another idea as it would like to feed the web visitor as much information as possible before letting him to the informatio
121. emote address and so on in addition to getters for the Servlet request and response objects central to the Servlet framework Jetspeed configures Turbine to instantiate a special RunData class This enables Jetspeed to augment the methods from Turbine with additional Jetspeed specific methods for example methods for getting the capability map for the browser 43 Modular Development Frameworks for Corporate Portals a Literature Review Actions When a user clicks a button link or portlet control an Action 1s fired The parameters sent from the browser includes the action name and which portlet the action concerns Turbine translates this into a specific action object and supplies this in the RunData object This makes for an addressable action scheme where portlets may address actions to themselves or another portlet 7 1 3 Framework features Portlet API There are two APIs associated with the Jetspeed portal project The one that is in use in the current development tree currently version 1 3 is the original one and will be discussed in this subsection The second 1s mainly a contribution from IBM and attempts to make the API detached from the Jetspeed and Turbine frameworks This API 1s supposed to be used in the version 2 of the Jetspeed framework but this version is currently not developed on The idea behind a decoupled API is to enable other vendors to make a portal server implementing the API without neces
122. ems unavoidable The development of a portlet API in the C language also seems likely However the emphasis on web services in the NET framework makes it quite possible that the web services based portlets as embodied in the WSRP standardization are the way that Microsoft will tout as the correct one if any This is based on the strong belief in programming language freedom that Microsoft shows and which also 1s a consequence of the web services approach as explained earlier 12 3 2 Other Languages Other languages frequently used in web development include Perl and PHP An interesting open source portal project built using PHP is PHP Nuke 5 This system is mainly an advanced content management system but it contains many add on modules for example discussion forum mail client news federation calendar and so on The project has had a so called code fork and another project called postnuke has been started providing even more modules The web site Slashdot popular amongst computer people are built using PHP and indeed have the concept of slashboxes portlets like windows that can be put on the single workbench a user have The website s software Slash 1s open source There are however no significant amount of portal efforts in other programming languages 12 3 3 Non browser Based Portals Java was once touted as the write once run anywhere language for every operating system However this has proved very difficul
123. ependency towards the vendor s own solutions is the rule not the exception in this category That 1s Microsoft s EIP like SharePoint Portal system 1s heavily dependent on other ey s Modular Development Frameworks for Corporate Portals a Literature Review Microsoft products essentially merging several of its own technologies into a web enabled system The last category consists of independent vendors that have developed a stand alone system that integrates multiple underlying sources Most often however these solutions need some system on which to run A full Java 2 Enterprise Edition application server or the lesser Java Servlets container is often employed As these vendors do not have any existing applications they are starting out from scratch That means that these frameworks may come without any features or portlets at all expect from a user management tool and similar administration specific tools Several vendors nevertheless have a library of already existing portlets and modules confer the analyses of Epicentric and Plumtree These modules may be used to quickly assemble some base functionality in the portal After that solution specific portlets for the company in question can be developed in a modular fashion expanding the functionality as the user needs emerge This thesis 1s primarily considering these two latter types of frameworks and the subject is thoroughly covered in the next chapter ND Modular Developme
124. ephan Hesmer and Ingo Schuster in addition to two other persons not mentioned earlier In the overview chapter of this document the authors state The Portlet API offered in the WebSphere Portal Version 4 1 is the first step toward the Portlet API standardization This seems as a good indication of what IBM will bring to the standardization table Because this is one of the most developed portlet APIs around and because it has been developed with help from multiple organizations it API is likely to influence the Java standardization process which is in progress in a considerable degree The WebSphere Portal is therefore deemed interesting enough to review in spite of the current lack of an actual product 7 4 2 Architecture and Architectural Features The Portlet Development Guide shows that several changes are made to the Portlet API since the last revision that 1s included in the Jetspeed CVS archives and the version included with the WebSphere Portal version 2 1 Whenever these APIs are compared the one included in the WebSphere Portal v4 1 is referred to as the IBM Sun did this with the Servlets specification 2 2 and 2 3 where the reference implementations Tomcat 3 2 and Tomcat 4 0 were developed at Apache Jakarta 68 Modular Development Frameworks for Corporate Portals a Literature Review APT while the one contributed to the CVS repository to Jetspeed which later were implemented in WebSphere Portal v
125. er functions and the user profiles does not have any locale specific properties embedded Conformance The BEA WebLogic portal system specifically requires the BEA WebLogic J2EE server and thus does not conform to the J2EE standard However the BEA 59 Modular Development Frameworks for Corporate Portals a Literature Review WebLogic J2EE server conforms to the J2EE standards thus being able to run components conforming to these standards Scalability The BEA WebLogic J2EE server is scalable and can run on multiple physical servers The portal system inherits this feature and it is thus possible to handle very many concurrent users 7 3 Epicentric Epicentric Foundation Server Epicentric is leading the portal market evolution is to be read in Epicentric s What s New white paper for their Foundation Server 4 0 Another bold statement from the company is their trademark Epicentric the Portal Platform Standard Epicentric have over 400 installations spread over about 200 customers Epicentric s sole focus is the portal market Epicentric have 335 employees and boasts over 100 partners Their focus is the Global 2000 companies Temenda d 1901 1100 am hy Main Vies Content Manager Explorer Vitri Explorar Partiiiiznn Bulag 35ag8i Ee Tet hie ere 5219 bytes GCN 10 06 AM a ppeuad Eda Preperiag B gokTISBIgTach hum teeth himi 6307 byter ONL OI 10 10 EM amp pproesad cas Prenatal e
126. erature Review are discussed alongside the arguments following while others of a lower level nature are presented later in Chapter 6 3 Functional Components of the Corporate Portal 5 2 1 Make Information Accessible The report from Shilakes and Tylman 1998 defines enterprise information portals as applications that enable companies to unlock internally and externally stored information This is a major focus of all vendors and analysts As a corporation grows older it acquires enormous amounts of data scattered in multiple data sources These systems hold information about customers orders internal resources and much more If a company merges with or acquires another company even more data in additional sources are gained Many companies make frequent use of externally stored information This might be online databases where industry standard information is stored online newspapers and many others As the internet still is maturing more and more information will be available online Table 1 contains some examples of internal and external information sources Internal eee Contact information e g customers suppliers and partners Sales organization leads prospects contracts and agreements drafts business intelligence gone communications e mail chat news bulletin board systems External Online newspapers magazines weather Company finances information e g http bizweb no for financial inf
127. erprise Operating System sess 9 8 1 2 Architectural Standpoint Webpage Assembly or Operating System 92 Go One or Pwo ter R BOGLIBE 2n oS ieee pa dmt 92 S14 Parallelizable Portlet ISGBndeEIBE usse heb ie NOR RC P a ar dion ae 94 SLS Poret O Ie n D 95 Q2 ilauonnandJlcangudse sotieesfanid mun ode stets diiit bts aste dicen ete 95 8 2 1 Dominant Language and Platform Java and J2EE ccccceeeesesssssesseesssssssseseeees 95 822 Vendor Lock Ince eti elle eles 96 2 5 Integration with BE teo Oise ia eius E eU oun dne 977 Po MEME Casal tt 98 o AAO c PS 98 8 3 2 Portlet Modes and Portlet Rendering eene 99 84 Configuration and User Management oot tete iet ate aet 99 85 Preinstalled Modules cundi II 100 O Framework COHCODLS uiui eet n tab Pi t eaa RO eta bui n bU RO Ee 101 9 1 Customization Preferences and Personalization eeeeeeeeeeeneeeeeen 101 2b vin TER T ans iunnaaae a a 102 DS WER COS CEG ON attacca dunt es seat cased cio sca natant A Ima eM us 102 92 72 MMOs SOM Oise tees ess este ica E IM IL MI MM ML ae MIO EE 102 OS Administration and DelegatlOD oe tr e EH IE NUS ENTRO Hadas 103 OA Mod l s and Portlet Applications eie e bot EE e E eau Ee stans 104 MEM au RO 104 96 Mu liple WorkDene leSuscentaron lii eh eonim tasto aea dox b dim baton P ions 104 AUI VAOS Sut dca See idco qunm diu tol deca oe PE idea EU pe
128. ersons from several other corporations and IBM finally came to an agreement over the design of the API some time after these discussions IBM released the WebSphere Portal Version 1 2 which implemented the Jetspeed API somewhat augmented for example a service package were added Later a follow on release version 2 1 was released IBM B December 25 2001 a document called Portlet API First Draft IBM C was added to the Jetspeed CVS repository This document was written by Stephan Hesmer Stefan Hepper and Thomas Schaeck all at IBM 38 Old Jetspeed mailing lists hosted at Working dogs http www mail archive com jetspeed list working dogs com New Jetspeed developers mail list hosted at Apache http marc theaimsgroup com l jetspeed dev amp 1r 1 amp w 2 Specifically Rapha l Luta and Glenn Golden have kindly answered the authors questions This is Christmas Day However the date seems to be correct as it says so both in the CVS logs and in the PDF file m s a Modular Development Frameworks for Corporate Portals a Literature Review Java Specification Requests for Portlet API Early in January 2002 IBM submitted a Java Specification Request for the creation of the Portlet API specification This became JSR 162 JSR 162 The contact person for the submission was Thomas Schaeck and the specification lead was Stefan Hepper Less than one week later Sun Microsystems Inc also submitted a
129. ese concepts again in this chapter 1s that this 15 a more low level view of how a concept is used in a portal development situation and how the concept is implemented in the portal system 9 1 Customization Preferences and Personalization Customization preferences and personalization refers to very similar concepts but refers to different levels of implicit or explicit control Customizations and preferences are explicit configurations done by the user like selecting which portlets that should be shown on a workbench and how the discussion forums should display their posts Personalization refers to implicit adaptations made by the framework based on who the user are and configurations done by the administrators Customization and Preferences When a user uses some configuration portlet and for example adjusts the way his workbenches appear it is referred to as customization Customizable elements in the analyzed systems include e Workbenches e Creation and editing of personal and group workbenches e How the portlets should be arranged the layout e Which portlets should be visible and in which order should they be shown e Joining of group workbenches e Theme Skin e Localization e Language e Date Time Numbers and Currencies In addition several portlets also have user configurable elements for example from which field and how many news items the news portlet should display This is often called preferences However some port
130. esigned to enable customers to rapidly build customize and manage multiple portal initiatives across the extended enterprise Epicentric argue that large corporations often has deployed several portal installations around the same time at different departments Epi C This has happened because a bottom up approach for portal implementation and installation has been employed Each department wanted their own solution driven by their own needs and they wanted it quick Often departments have chosen different platform standards giving a heterogeneous mix of portal platforms Now these corporations are in the same situation that portals were conceived to remedy multiple intranets spread across the departments without the possibility to share information This prevents the true value of a business portal which 1s Tested Platforms Matrix http www epicentric com solutions efs testedplatforms 40 sp3 jsp 30 This seriously impact performance though as every session must be serialized to a sequence of bytes stored onto the database persistent store and then finally read and de serialized again on every request The author finds this approach somewhat counter productive as it only moves the single point of failure one step backwards completely relying on the database This definitely hints at a fact that most vendors database solution is more mature than their application servers are 6 Modular Development Frameworks for Corporate
131. euse of knowledge This workspace is achieved by developing certain collaboration applications as well as tools that enable information to be accessed and workflow systems available within the portal Figure 5 1s an information based model of the corporate portal and demonstrates the three major components that constitute the shared information work space Chapter 5 3 Functional Components of the Corporate Portal contains further descriptions of the applications and system necessary to facilitate these components 2 Modular Development Frameworks for Corporate Portals a Literature Review Communication Space Channels for conversations and negotiations on collective ontent Space Information access to corporate data and documents Portal Shared informatio work space Coordination Space Work flows and routines to support cooperative work action Figure 5 The corporate portal as a shared information work space From B Detlor 2000 The information content space represents information storage and retrieval and have been reviewed in the previous section The communication space refers to the communication between the employees in the enterprise Here collective interpretations and decisions can be made and meanings exchanged This will help users interpret information review it and put new or refined information back into the system Lastly the coordination
132. eve those preferences This 1s done using the HTTP header exchanges described in the previous section but the burden of handling this exchange 1s offloaded from the developer as the framework handles this The Plumtree portal features administrator configured caching of portal content In addition an enterprise class gadget framework features another layer of caching on the portlet level When the user reloads a page or does a drill down or similar activities requiring the re rendering of the portlet the data 1s fetched from the cache instead of burdening the enterprise application with a new query CGI Common Gateway Interface This is a simple protocol for how a web server communicates with external programs HTTP headers server variables and settings and similar properties are communicated to the invoked program using environment variables variables that are available within the run time of a program s execution The output from the program is supplied back to the requesting browser EE Modular Development Frameworks for Corporate Portals a Literature Review In Plumtree C Plumtree states Plumtree is developing or has released Enterprise Class Gadget Frameworks for systems such as SAP R 3 PeopleSoft 8 and Siebel Sales Plumtree is also developing a similar framework for developing stand alone gadget web services not requiring an underlying enterprise application These portlets would contain their own application lo
133. evelopment Kit The portlet development kit alleviates the developer of the complicated communication between the portal the provider and the portlet hiding the intricacies behind simpler Java APIs The Java PDK operates by translating the remote procedure calls from the portal to normal method invocations on Java interfaces However the PDK from Oracle is somewhat chaotic with lots of classes referring to each other and several of the API s methods lacking documentation It may seem like the PDK has been through a couple of generations without a complete overhaul Compared to the clean APIs of the new Jetspeed APT and the IBM API Oracle s API falls through as unstructured A central element in the PDK is a Servlet that interfaces between the portal and the provider The developer is expected to configure his servlet container himself providing the necessary configuration parameters to enable the servlet container to load this servlet Oracle points out that this servlet may run on any servlet container including BEA WebLogic IBM WebSphere or Apache Tomcat Portlet Definition A portlet is implemented by defining as set of controllers a renderer and optionally a personalization manager and a security manager These definitions are registered in a XML file This XML file is read by the provider within the PDK on servlet container startup When the portal asks which portlets the provider provides it replies with this list Acce
134. ework and not the portal system as a whole Functionality 1s thus defined to include the functional components architecture and architectural features and framework concepts and features of a corporate portal development framework These terms are further defined in the Chapter 4 Definitions The international standard ISO IEC 9126 1 Information Technology Software Quality Characteristics and Metrics defines the software quality characteristic functionality as The capability of the software to provide functions which meet stated and implied needs when the software is used under specified conditions whose sub characteristics are suitability accuracy interoperability compliance and security It is important to remember that this thesis scope is to assess the functionality of the frameworks not the actual corporate portals This thesis definition of functionality diverges somewhat from this standard See also appendix A Definitions used from ISO IEC 9126 1 Modular Development Frameworks for Corporate Portals a Literature Review 4 Definitions Definition and explanation of some important and frequently used terms e Architecture refers to the architectural building blocks that constitute the portal system This includes the hardware the operating systems and any application servers and databases necessary to run the system It also refers to how the portal system itself 1s constructed for example how the
135. ework concepts and features i pete tete ti o t bte t ue ite teda ee beds 63 7 3 3 Software Quality Model References ccc cccccccccccceeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeees 66 74 JBNL Websphere Portal teint perte uiu lot xad ee a E antt fee d tein 66 TAA Historical Review Or the Portlet ADI ue cC te cR En 67 742 Architecture and Architectural Features 4 eee t t obo e P Rr 68 FAS Framework concepts suede tet e oat aM Mati aite 70 Modular Development Frameworks for Corporate Portals a Literature Review LAA Framework features ioni tua too iebr ooo iaa EAER oett taque euim ens 70 145 Software Quality Model References een ere E orla ion tbt Ra o P RR eds 74 dey Oracle Oracle Portals ete dO cu ME 75 T5 Architecture and Architectural Features oe ett e e e rp 76 ko Framework COlCODIS 5 ed deat edad ua Moda atis a edite 79 Es IPAM W OL CATES aa tore tete Rata etin dern t based ond heat dra t aded en onu 80 154 Software Quality Model Reteretces 2e totae o plar dnd ie odisse 82 ko Plumtree Plumiree C orpotate Portal 5t ppt UD ESI NISI M NIME 82 7 6 1 Architecture and Architectural Pea3tutes eco e E ME ER ME ES 83 7 0 2 Framework Concepts dtd fedbufes ui oH o MU 86 7 6 9 Software Quality Model References ones o m hm D md 89 8 Architecture and Architectural Features esses 9 Bel eh Te Vel ATCHI GC CUS Deeds ias cedet os eui tet oae hav cann os eus acad a ostia tdm oup 9 8 1 1 Portal System as Ent
136. ey supply beta versions of such PDKs for web based portlets that are fetching information from simple web pages and for interfacing to the emerging Web Services 93 Modular Development Frameworks for Corporate Portals a Literature Review Since portlets can be programmed in any language technology bridges are eliminated The portlet can be programmed in the same language on the same platform as the underlying resource it will access The system is scalable in the way that an administrator can place the individual portlets on different physical servers Some portlets may be hosted together on one physical server while other more resource intensive portlets can be hosted alone on one physical server or in Plumtree s system on multiple physical servers However there is a potential bottleneck with the saturation of the portal server itself Faults are effectively isolated since one portlet cannot possibly the whole server The Plumtree server stops accessing the portlet if 1t crashes or times out several times and instead starts polling regularly to check whether is has come up and 1s acting normally again Nevertheless the portal server itself 1s a single point of failure Plumtree also argues for a heightened security with this model As the portal server does not access the underlying sources directly but have to go through the portlet server one extra layer of security 1s introduced 8 1 4 Parallelizable Portlet Ren
137. f Jetspeed to get a fuller picture of this 11 Modular Development Frameworks for Corporate Portals a Literature Review these more or less directly only depending on the buffering present in the underlying systems IBM is explicitly giving the portlet a handle to the output stream on process invocation while BEA 1s using a system of recursive JSP file inclusion giving the same net effect This system have the distinct disadvantage that if the portlet crashes while for example in the middle of a HTML table rendering the resulting web page will be garbage The user will be fed inconsistent markup which depending on how strict the browser processes HTML will result in an incomprehensible web page This will be especially problematic if the error does not go away by itself as the portlet is still sitting on the workbench and will crash on each reload Name Clash Avoidance With multiple portlets on one web page possibly several instances of the same portlet there is a definite problem of name clashes There is a chance that two portlet can both be named the same and that two portlet developers could choose to name any HTML element or JavaScript variable the same Therefore both the id of the portlet and any variables in the outputted markup must be augmented with some instance specific id 10 5 2 Input from User to Portlet Addressing In a normal full screen web application the URL that should handle the input from th
138. family of products including the portal 1s extensively using the paradigms and features of the Java 2 Enterprise Edition framework Concepts from this framework for example web application enterprise application enterprise java beans and deployment descriptors is used frequently The entire portal is made up of standards compliant elements to such a degree that one wonders why it 1s required to run on the WebLogic server Appendix B contains a rudimentary overview over the J2EE platform 49 Modular Development Frameworks for Corporate Portals a Literature Review BEA use a graphic user interface called E Business Control Center EBCC to create and edit many of their servers properties and the functions within the framework The primary function of this console is to create and edit XML files within the system It can also using a special synchronization mechanism communicate directly with the WebLogic Server and thus update applications on the fly Webflows To understand the low level architecture of BEA s portal one important feature of their system must be briefly described namely Webflows This feature helps developers make extensive multi screen applications A webflow is based on a flowchart style model Figure 14 shows a part of an extensive webflow File Tools Window Help ot gt iac a0 eds ed portal T iar r Webflow portal 6X HE aI FE Ue
139. fferent parts of the finished page are done using a rendering system currently supported are WebMacro Velocity Freemarker and JSP Services and functionality from the Turbine framework include database connection pooling HTTP parameters parsing event based action handling job scheduler access control system role based security model and integration with several database object relational tools including Turbine s own Torque Jetspeed Jetspeed 1s implemented as a web application on top of Turbine It uses much of Turbine s functionality and includes some portal specific functionality as well Depending on the chosen template language Jetspeed uses one of three Turbine pages The view 1s assembled by executing the different parts of the page as explained in the previous subsection Three navigation bars are in use in the default Jetspeed installation top bottom and left The screen is executed which in turn executes the correct rendering template called Controller based on the user s chosen portlet layout This template 1n turn executes the different portlets residing 1n the controller s PortletSet by invoking them through a Control template that outputs the portlet frame and control buttons like close and minimize The control template finally includes the portlet content This system is explained in greater detail in the subsection Portlet APT There are some features that seems misplaced as to in which of the two frameworks
140. fine EIP in a manner favoring one s own vendor or analytical interests Vendors are eager to have their definition accepted as the prevailing one thus branding the other vendors products as inferior Analysts would get ahead of over other analysts and consultants 1f their definition were the most cited one The terms corporate portal and enterprise information portal have become the most frequently used and they are used interchangeably Despite the different terms and definitions every analyst and vendor recognizes the work of Shilakes and Tylman making their definitions the most cited in the field Still there has been some critique over their lack of collaboration focus in their definition Dias 2001 Several analysts would like a corporate portal definition to place a stronger emphasis on the cooperation between users and generation of information This chapter is further divided into four subchapters The first explaining in detail how the portal portlets and workbenches are experienced by a user Secondly a set of arguments for the existence of corporate portals is set forth along with the requirements these arguments lead to The third subchapters details a set of functional components typically found in corporate portals while the last subchapter explains a type of categorization of the portal systems useful for the selection of vendors in the vendor analysis Enterprise Collaboration Portal Enterprise Knowledge Portal
141. from familiar operating systems Hopefully these systems are also easy to like since they are supposed to make one s work and duties easier These characteristics are not relevant to the thesis main goal though and are thus not included in the definitions list Vendor lock in is a term referring to the fact that 1t often 1s difficult to move away from a vendor when one first have started to use some of the vendor s products As no definition clearly points to this problem the definition replaceability 1s therefore extended to also include this software s capability to be replaced by another product 139 Modular Development Frameworks for Corporate Portals a Literature Review 15 Appendix B Java 2 Enterprise Edition The Java 2 Enterprise Edition specification J2EE is a set of standards set down by Sun and several working groups consisting of many prominent vendors The standard is especially tailored towards distributed internet enabled applications and other environments where resources are spread out The application model used in the J2EE environment is shown in Figure 40 Client Side Server Side Server Side Enterprise Presentation _ Presentation Business Logic eer Browser Pure HTML Java Applet Desktop Java Application Other Device a Client Figure 40 The J2EE application model From java sun com J2EE overview The full specification encompasses 13 different specification an
142. g Content management is examined further in Chapter 6 3 2 Content and Document Management Once validated the knowledge can be released into the knowledge domain for example by publication into the knowledge base Finally restructuring concerns the aggregation and processing of the knowledge to meet a specific purpose leading to additional data that will complement the existing knowledge In the knowledge base this 1s facilitated by the linking and referrals between different information entities Expertise Localization Portals can furthermore assist in the localization of expertise PortalsCommunity 2002 A large corporation may have employees located all around the world An employee might be at one location struggling with a difficult problem At a different location another employee might know the answer to this problem Identifying such answers is often a complicated process as some answers may be devised only by a person who has the necessary knowledge Despite the readily available information the answer may still be difficult to figure out Human resource management systems are used to char and measure each employee s knowledge and expertise fields These systems enable users to look up anyone in the corporation who might have the knowledge necessary to solve the problem at hand Informal and loosely structured information sharing systems like discussion boards enable the user to direct their questions to a relevant forum B
143. g eyebrowse ReadMsg listName jetspeed dev jakarta apache org amp msgNo 4273 47 Modular Development Frameworks for Corporate Portals a Literature Review 7 2 BEA WebLogic Portal BEA is one of the best known Java application server providers BEA states on their web site BEA is the world s leading application infrastructure software company with more than 12 500 customers around the world including the majority of the Fortune Global 500 In the Metrics of Success section they boast that they have according to every major industry analyst the world s number one Java application server They have more than 2 100 partners which offer more than 1 000 Built on BEA applications BEA s family of products is called WebLogic The BEA WebLogic Enterprise Platform embraces their full set of products This platform includes WebLogic Server WebLogic Portal WebLogic Integration and WebLogic Workshop BEA states in the WebLogic Portal Datasheet BEA A BEA WebLogic Portal is a cornerstone of the BEA WebLogic E business Platform The WebLogic Portal replaces BEA s former products WebLogic Campaign Manager and WebLogic Commerce Server These facts have many implications for the focus of features in the portal framework In this analysis only the WebLogic Portal features will be investigated and the e business features will only be skimmed BEA s portal solution including the application serve
144. g hard to achieve These matters have made the review process for the Apache Jetspeed portal time consuming P Jetspeed FAQ http jakarta apache org jetspeed site faq html iN Modular Development Frameworks for Corporate Portals a Literature Review However there are several reasons why the project still 1s interesting to review The feature set of the platform is rich and the system s portlet API and associated services are interesting The system 1s open source and free which alone are interesting properties Lastly the ASF is a member of the Expert Group currently designing the Java Specification Portlet APT The Apache s next generation portlet API which were developed in conjunction with IBM will most likely affect the final Java standard Portlet API to a considerable degree Apache and IBM s systems are therefore interesting concerning which functionality will be included in this standard 7 1 1 Architecture and Architectural Features Jetspeed is as mentioned built upon the Turbine web application development framework Turbine is built on Java Servlets Jetspeed implements apache s current portlet API and on this API the developer programs portlets The resulting technology stack is pictured in Figure 7 pesedsjer Java Virtual Machine Operating System Figure 7 Jetspeed Technology stack The Jetspeed system needs a base database This is used
145. g products Using the categorization described in Chapter 5 4 Portal Categorizations only the two last categorizations are deemed to be of interest as these companies main 33 Modular Development Frameworks for Corporate Portals a Literature Review intention is to provide frameworks for the development of corporate portals These are the Existing vendors new market opportunities and New entrants categories Based on this bias from the categorization and input from CoreTrek a set of vendors have been selected for the analysis These are listed in Table 2 Included are two of the new entrants dedicated specifically to portal systems a couple of the large names in the software industry and the open source framework Jetspeed from the Apache Software Foundation Apache Software Foundation Product Jakarta Jetspeed EIP Sole product No Apache have a large set of products both based on the Java platform and other programming languages Most known for the Apache Web Server Apache is an Open Source community Type of e Few high level overview and architectural documents documents e JavaDoc API documentation e All source code files Installed Yes version 1 3a2 binary distribution BEA Product BEA WebLogic Portal Sole product No application infrastructure including one of the leading J2EE application servers Type of e Very good documentation both high level overview and documents low
146. ge might very well contain inconsistencies This can lead to the situation where the entire portal page is not able to render on the client s browser until the error is cleared Changeability The portal system is a J2EE enterprise application and each part of the system is defined using the standard J2EE deployment descriptors in addition to the BEA specific deployment descriptors The JSP files controlling the rendering and the webflow describing and controlling the flow of operations are also readily available Thus the system is changeable in most every way Analysability Testability The BEA J2EE server has some interesting statistics associated with all running servlets and JSPs For each of these an access count is kept and the low high and mean processing times are updated for each access This is an extremely valuable feature when a developer is trying to optimize a page or trying to make out why some workbench is too slow However the multiple recursive inclusion of great many JSP files makes the system hard to decipher If for example a mismatched element is discovered in the resulting workbench markup language it 1s often virtually impossible to decide where the element comes from Adaptability BEA has some support for internationalization however there are only two tags in the tag libraries that tend to all internationalization and those only involve the language Date times and numbers seems to not have any help
147. ger pass on the flow before all these fields are filled When everything 1s filled out properly the manager hits some initiate new employee workflow A task 1s then submitted to the next persons in the flow parallelizing all the tasks that can be done simultaneously Operations where some information may be incorrect can be sent back to the person which 1s responsible for that part e g when the accountants department tries to fill in the social security number for the employee the accounting system find the information incorrect The form can then be sent back to the manager with a note of the problem When the accountants department has done their task they hit a next in flow button sending out new notifications to the persons which tasks are next in line When all the operations are completed the manager might get a final notification which informs him of the completion of the new employee workflow A portal system is very well suited for having good workflow systems embedded in them since the portal spans the entire corporation and by design and intent integrates towards several of the underlying systems that must be accessed to fulfill each task 5 3 6 Alerts and Notifications Alerts and notifications are similar concepts often using the same mechanism in the portal An alert is sent when there is a need to notify the user of some condition that has been met e g that there are 15 minutes left to the scheduled meeting or
148. gic and data storage Multiple Workbenches and Communities A user may define multiple MyPages which are user defined and customizable workbenches Plumtree in addition have a concept of communities Communities may be created by both the administrator of the portal server and by special users who have the ability to approve portal content A user may be enrolled in several communities The community leader may enroll him with a mandatory membership or he may choose himself to enroll into communities to which he is eligible The enrollment in a community gives the user a set of extra workbenches which in effect is shared between the community members The administrator may choose to display the extra workbench as a tab while the employee defined communities will usually list beneath a single tab The workbenches include up to three columns of portlets Look and Feel The user may choose between 18 different color schemes The use of themes where the entire graphical display of the workbench is changed is apparently not supported Internationalization and localization The Plumtree portal is already available in eight languages All text strings are separated from the user interfaces and stored as separate XML files This includes all help files The character set used for internal representation 1s UNICODE thereby being able to represent most any known language s character sets By choosing a locale the user implicitly also selects
149. h information Allen 1977 cited Detlor 2000 p 94 states that the convenience given by such accessibility can promote the acquisition and use of information throughout the entire enterprise as individuals tend to use information characterized by high accessibility 5 2 2 Reduce Information Overload Although making information accessible 1s an enormous advantage of the portal system there is a problem at the opposite end of the spectrum This is the information overload problem where users are swamped with information from every corner in the enterprise Grammer 2000 Thus making information easy accessible is not the solution in itself The amount of information that a user 1s required to run through in order to gain the necessary knowledge should instead be reduced In addition the amount of time required to find the exact piece of information needed should be minimized Users must feel confident that they have found all the relevant information available In order achieve these objectives key elements in a portal should include information aggregation good categorization and navigation tools throughout the information sources and proper searching tools that can search multiple information sources in one search 4 Modular Development Frameworks for Corporate Portals a Literature Review 5 2 3 Information Aggregation A lot of information refer to other pieces of information or make more sense when grouped and com
150. hair of the WSRP Technical Committee is Thomas Schaeck from IBM which also acts as IBM s contact person on the JSR 168 Likewise Sun s specification lead of the JSR 168 Alejandro Abdelnur is listed as Sun s member of the WSRP Technical Committee It thus indeed seem like the communication paths between the WSRP and JSR 168 are established 12 1 4 Possible features included in the standardizations Based on the preceding analyses some probable high level features and concepts can be listed for the portlet API and Web Services Portlets standardizations These are concepts and features that seems very interesting to include in a common standardization effort but which have not been implemented by all vendors Themes Themes control is a definite must and is included in all systems However the fonts and font sizes and colors seem to be neglected in most systems For HTML a standard set of Cascading Style Sheet styles definitions and color variables should be defined so that themes easily can be implemented A theme would in addition to workbench layouts and similar high level design features also define the standard styles and colors The entire portal design can thus be changed enabling the use of high contrast inverted colors and large font themes This has been taken care of in the WSUI standardization effort WSUI Stand alone portlet applications At least IBM has implemented this architectural feature but the providers con
151. hanged If it has changed a copy of the old file or the changes between the old and the new file 1s stored in some kind of archive thereby enabling users to track the changes for each revision and to fetch old copies of the file 5 3 3 Searching The search function of a portal system is a very important tool The searching system is indexing content and documents in the portal and from different sources across the enterprise enabling retrieval of data and documents by the user entering some search criteria Specifically the content of the taxonomy is searched and the results might send the users to the correct node in the taxonomy thereby giving them a relevant context from which to drill further down into the data Some systems make use of an external third party search engine For example the Epicentric system uses the Inktomi Enterprise Search Engine while Plumtree uses the Verity search engine The searching system might be facilitated by a so called crawler This 1s a program that runs through the company s existing files and documents indexing the content and metadata about each file This enables a full search through all information in the company through one single search interface Plumtree have introduced the concept of network searching called federated searching by Verity The idea is that by assembling a single search criterion the user is enabled to search through multiple data sources 9 3 4 PDA integration and syn
152. he J2EE specification and a tighter integration with the application server How the integration between the different portlet web applications should be done how the portal itself 1s supposed to be implemented and how the loading and unloading of the portlets 1s done 1s not elaborated on in any of the documents available Since the system 1s not available yet further aspects of the architecture are difficult to deduce Clean API The API and its methods are made in a vendor independent fashion and 1s mostly an extension to the already existing well defined Servlet API version 2 3 In effect it 1s a way for a web page to be constructed from multiple small java classes portlets working independently instead of the entire web page being constructed by one piece of program logic the servlet This will be reviewed more thoroughly in the next subsections Relationship and similarities with the Servlet API Both the Jetspeed API and the IBM API are similar to the Servlet specification For the Jetspeed API the reason for this was more cosmetically than a necessity the API should be easy to learn for people already familiar with the servlet API and it should be easy to port a servlet to the new portlet environment For the IBM API the servlet similarity is more of a requirement since the Portlet API is a direct extension of the Servlet API Confer with Appendix B for a review over the different aspects of the J2EE specification
153. his way every vendor tries to lock their customers tighter and tighter into the vendor s full product suites In many ways it can seem like vendors actually tries to find places where the standard does not define any particular behavior Such holes are exploited mercilessly developing incompatible solutions luring the customer to buy additional software from the same vendor This attitude can be seen to some degree with the vendors having an existing application server product BEA IBM and Oracle Diametrically Epicentric s portal system is also built upon the J2EE architecture but this vendor does not have their own application server and thus boasts of the large number of different application servers the portal can run on With the standardization of a Portlet API and web services portlets this will have to change More on the standardization efforts and their impact is found in Chapter 12 Portal Framework Evolvement Apache Jakarta Tomcat http jakarta apache org tomcat index html Jetty http jetty mortbay com jetty index html GNU Paperclips http savannah gnu org projects paperclips JBoss http www jboss org 96 Modular Development Frameworks for Corporate Portals a Literature Review 8 2 3 Integration with J2EE For the systems that are written in Java the degree of interaction between the J2EE architecture and the platform system varies considerably There are several areas where this is
154. hroughout a page when accessing resource bundles via the lt 118n getmessage gt tag In addition three of these libraries are special to the portlets environment The Portlet library includes tags for referring to portlet webflows generating HTML forms and validating the input from the user and for referring to the portlet related events like KSR Modular Development Frameworks for Corporate Portals a Literature Review maximize and unmaximize The Portal library similarly has tags that refer to the portal s webflow and to generate portal scoped forms There 1s also a tiny utility library used within the portal s own framework Webflows within the portlets The webflow system is not limited to full page views but 1s also able to keep a flow of operation within single portlets This system also enables multiple portlets to communicate to some degree This 1s facilitated by the fact that if one portlet gets for example a minimize event all other portlets on the page would get a refresh event which are accompanied by the portlet namespace and the origin of the event 7 2 4 Software Quality Model References Fault tolerance The total reliance on JSP makes for tricky coding and unversed coders may make portlets that may crash under given circumstances As the JSP files are included recursively and sequentially each unit must be totally correct in execution If one unit crash halfway into its markup generation the resulting pa
155. hus changing the current view of the portlet For the portlet to remain on the chosen page of articles during a reload of the page the x Modular Development Frameworks for Corporate Portals a Literature Review selection is kept as a parameter in the PortletSession object When the user logs out and then logs in again the PortletSession object is destroyed and the selection will thus be reset to show the last then articles Client Capabilities and Multiple Markup Languages Upon invoking the methods in the Portlet interface the PortletRequest object may be queried for which type of client 1s connected The returned Client object contains information about which user agent is connected which markup or markups that are supported which mime types that are supported and which capabilities the client support Capabilities include level of HTML whether JavaScript 1s supported and so on This enables the developer to tailor its output for different clients and may do this based on different levels of functionality supported by the client Name clash Avoidance Since there can be several portlets on one page and even several instances of the same portlet a definite possibility of name clashes arise in addition to the addressing problem of how to specify that a argument should be directed towards a specific portlet This 1s solved by letting a portlet runs within its own unique namespace It may use one of several methods to get hold of
156. ic and IBM WebSphere do this by using the attached database to store the session data between requests This is described thoroughly in their Scalability and Capacity Planning Overview paper Epi A Modules and Pages A Module is the term Epicentric uses for a portlet The modules are arranged on a Page Modules may be programmed in Java using the native server API or using the Modular Web Services framework which 1s described later Portal Sites The Epicentric Foundation Server 4 0 allows several Portal Sites to be hosted on one server installation A site within the server 1s a collection of portal components including pages modules navigational tools and a theme and administrative functions given to a designated portal administrator The sites are hosted on separate domains e g www divisionA com and www divisionB com or as separate paths beneath one domain e g www corporation com siteA and www corporation com siteB The set of portal sites that are hosted on one server 1s called a Portal Network A user may use multiple sites on the system depending on their permissions The portal network also enables server and site administrators to share and re use site components between sites Enterprise Portal Management From Epi B Epicentric Foundation Server 4 0 1s the industry s first Enterprise Portal Management EPM system Beyond simply managing employee portals Epicentric Foundation Server 4 0 1s specifically d
157. ic role See below for a discussion of roles and groups and the content will then have some access attributes set to it The next time a user is watching the specific portal page the new content will be delivered to the user by embedding it into the HTML output The content can be created by some special tool for example a dedicated HTML application or there might be a content editor embedded directly in the portal The latter approach is to prefer when it is desirable that everybody should be able to contribute and comment on the content Document and File management 1s very similar to content management except that such systems handle documents and files instead of content meant for embedding in the portal s pages The publishing cycle may still be used as e g a product data sheet os Lr Modular Development Frameworks for Corporate Portals a Literature Review will have to be accepted by the sales manager or product manager before a sales person have access to it to and can give it to a customer Document and file management often make use of check out and check in procedures This is meant to prevent several users to simultaneously download a document edit it and then upload it thereby loosing one of the users changes Shilakes and Tylman 1998 In addition management systems like this can easily handle versioning and change logs By comparing the newly uploaded file with the existing one the system can se if it really c
158. ication is employed A concrete portlet application is parameterized by a PortletApplicationSettings object and there may exist several of these A concrete portlet application contains at least one concrete portlet from the portlet application but does not need to contain all of them Built in Caching The Portlet API facilitates server facilitated caching This is done by letting the Portlet implement a getLastModified method which should return the milliseconds since the Epoch The portal may use this value by checking it against the value returned the last time this same portlet was rendered If it returns the same value as last time it can skip the rendering stage of the portlet since it apparently has not been modified A special value signifies that the portlet does not want caching thus the portal server should always render the portlet fully Listeners The portlet may implement a set of listeners to be notified of certain types of events The PortletSessionListener interface makes the portlet aware of users that establish a session which in most circumstances means that the user logged in It also notifies all portlets of a user shutting down a session which happens on logout or timeout The PortletPageListener gives the portlet a chance to output data to the output stream before any of the servicing methods are being called on any portlet In addition the portlet may output data to the stream after all service methods for all
159. in period of time the length of which is assessed by its recoverability 2 Externally availability can be assessed by the proportion of total time during which the software product is in an up state 3 Availability is therefore a combination of maturity which governs the frequency of failure and recoverability which governs the length of down time following each failure 14 1 3 Maintainability The capability of the software to be modified NOTE Modifications may include corrections improvements or adaptation of the software to changes in environment and in requirements and functional specifications Analysability The capability of the software product to be diagnosed for deficiencies or causes of failures in the software or for the parts to be modified to be identified 1375 Modular Development Frameworks for Corporate Portals a Literature Review Changeability The capability of the software product to enable a specified modification to be implemented NOTE Implementation includes coding designing and documenting changes Stability The capability of the software to minimize unexpected effects from modifications of the software Testability The capability of the software product to enable modified software to be validated NOTE Values of this sub characteristics may be altered by the modifications under consideration 14 1 4 Portability The capability of software to be transferred from one environment to an
160. iner is aware of it and may load and initialize the code Secondly the portlet must be defined in a separate file so that the portal system may invoke the code The different definitions have different scope which will be made clearer in the next subsection Class Instance Concrete Concrete Instance and User Instance As with the Servlet specification only one portlet 1s ever physically instantiated This is called the portlet class instance A Concrete Portlet 1s a portlet parameterized by a single PortletSettings object Such concrete portlets are created whenever a portlet application is installed since a portlet deployment descriptor must contain at least one concrete portlet for each portlet defined In addition an administrator may create multiple concrete portlets by configuring a portlet thus giving it multiple PortletSettings objects possibly containing different parameters When a user places a portlet on one of his pages or an administrator places a portlet on a group page a Concrete Portlet Instance 1s created This 1s a concrete portlet parameterized by a single PortletData object The PortletData object stores persistent data about this single instance residing on a specific page The PortletData object s parameters is only to be changed by the portlet itself The relationships between these different entities are shown in Figure 26 Deployment Descriptors Runtime Configuration User or Gro
161. ing brief explanations to some of their technologies In addition several analysts have published articles where summaries of a selection of vendors are given The technology consultant company Owendo 2002 have published a review entitled The Lowdown on Enterprise Information Portals EIP in which they give brief outlines of 13 different vendors An article from John K Waters 2000 titled Portal Wars also have very short outlines of 30 different vendors These articles have given some start information of what to expect from the vendors Documentation All relevant documentation that was available from the selected vendors websites at the time of writing has been downloaded for the analyses Places searched were both in the public part of the sites and the sections available by registering as a user This includes so called white papers data sheets technical overviews programming tutorials and similar documents It is worth to notice that these companies websites are very dynamic in nature Documents that are available one week may be deprecated the week later In addition some site for example Sun s Java site operates with session based downloads thus rendering the URLs meaningless It is therefore often difficult to give a proper URL reference pointing to a specific document Appendix C References contains the title of the document and if the URL 1s too difficult to handle the filename Single web pages are
162. ing out what the corporation has to offer Anonymous webvisitors are persons whom the web server cannot identify It 1s often possible to follow such a user s moves around the website nonetheless thereby getting an impression of what anonymous users find interesting and what information they are seeking By watching variables such as which web page 1s more popular page viewing time and number of clicks before localization the site can be tailored and polished to suit the information needs of the persons that visit the site In addition searching terms 1s valuable as they suggest what users are looking for and which information 1s too hard to find Registered webvisitors have given the corporation information about themselves most probably in exchange for some special resource It 1s often easier to track these visitors than anonymous visitors as their so called session with the web server 1s well defined In addition repeated visits are easier to track as the web server might both recognize their identification automatically and because the user will give some credentials typically some username and password selected by the user in order to open up the special resources These people probably have some tighter relationship with the company since they are willing to take the time to provide personal information Analyzing their moves within site might give even more information about the corporation s site Both of these groups are
163. ion ee Modular Development Frameworks for Corporate Portals a Literature Review sources When the portal needs information about a particular portlet or needs a portlet to be rendered to a web page it communicates with the provider Providers can be used for grouping of portlets into functionally groups In addition provider groups provide for an extra level of aggregation Providers may be developed in several ways from programmatic to declarative There are broadly two different types of providers Web Providers and PL SQL Providers Workbench Wo nch Reques sponse Mainframe Underlying layers Underlying layers HW and OS Figure 29 Oracle Portal connecting to Web providers connecting to backend data Communicating between the web provider and the portal is done using SOAP remote procedure calls over HTTP A remote web server does not have to be Oracle s it can be any application server This enables the provider and portlet logic to be made in any programming language as long as it input and output may be exposed over HTTP This setup is shown in Figure 29 The output of such a portlet may optionally be run through a XSL transform To alleviate the portlet developer for the burden of the somewhat complicated remote procedure calls and transactions that is needed for the portal the provider and the portlet to communicate Oracle have made a set of Portlet Developmen
164. ion may be loaded back onto the production system Modular Web Services and Web Services User Interface Using the web services protocols Epicentric s Modular Web Services technology MWS enables Modules to be hosted remotely and serve views to the portal site This technology may be viewed as extending Epicentric s Module API to a remote host The SOAP XML based protocols distances the implementation of the module from the server platform enabling MWS to be written in other languages than Java Epicentric have made MWS versions for both JSP and ASP Web Services User Interface WSUI 1s an exciting standard initiative proposed and driven by Epicentric It is developed because of the fact that Web Services as they stand today 1s made exclusively for computer to computer communication The protocol would be excellent for remote portlets though and this fact is what has made Epicentric develop this standard The idea is that the WSUI layer defines the user interface and the methods that should be run on the remote Web Services interface when the user makes any actions on the client for example by clicking on a button or submitting a form This initiative has gotten industry attention and several of Epicentric s customers and partners have teamed up behind it and established a working group There is a dedicated website for the work at http www wsui org However the standards body Oasis has decided to initiate the exact same type of pr
165. ion options in the top right corner HTML and WML The stock Jetspeed distribution includes support for HTML and WML As can be seen from Figure 11 both the WML customization screen s layout and colors selection drop downs are grayed out The different markup languages are configurable and adding a new language is easy The portlets must both be programmed to handle multi output and configured so that the framework knows which portlets handle the different markup languages In the test installation only the three portlets shown in Figure 11 supports WML Roles and Permissions Turbine uses a permissions based role system One or more roles are associated to a user A role consists of one or more permissions A developer may query the AccessControlList object for whether the user has a specific permission and whether the user is assigned a specific role Omnipresent RunData object A special object RunData is passed around through all the methods in the Turbine framework for each browser request The object have methods that enables developers to access both Turbine and Servlet specific objects and methods Turbine methods include getters for the AccessControlList which Action 1s invoked getter for an object representing the active user and similar attributes set by the framework It also includes setters and getters for the selected Screen and Layout Servlet specific methods include convenience getters and setters for cookies client r
166. ionality and will not be further discussed However an interesting yet simple service provided with the IBM portal system is the credentials vault This 1s a system facilitating single sign on by keeping a user s credentials for different systems in a protected and encrypted store The store can both be a system default or interface towards already existing single sign on system that already have a credentials store 1n place The credentials vault may be used in two ways The first most straightforward is to use the vault as a bank requesting a specific user s credentials for a specific resource and subsequently establish and programmatically authenticate the connection to the resource The second more secure method 1s to ask the credentials vault system to establish and return an authenticated connection for the specific user to the specific resource This latter approach is the preferred one as the actual credentials for example a username and a password never are exposed to a potential malicious portlet 102 Modular Development Frameworks for Corporate Portals a Literature Review 9 3 Administration and Delegation The portal administration consists of many tasks including creation of the portal managing users and groups managing access to the different objects within the portal and creating workbenches for specific groups of users Most portal system has a distinct focus on administration and the delegation of administ
167. iterature Review 10 7 State Persistence Preferences and Configuration ccccccccccccccccccccccceeeeeeeeeeeeeeees 113 10 8 Roles and PEmmisSiOns x26 basado cas et etc a cdissetan ale eesti eases 114 10 9 liema ona haO concionem atout dE EMI MUNI PEE 115 IN E Gc 115 ITSottware Quality Model 4 ei eoe a tei a nates 116 11 1 Lac Gona N dioses ioc etis orani ntt etti deest abes citu it asset tune dca e de ced s 116 11 2 Renabli gop ee eee aestate eed eee eee 117 11 3 Maimtainabili sus ocuie ceca PSout ipsc ate Ui o UMS UP MEUM C UFU E US URDU UU 118 11 4 Pona O T sc onec tam nM NM MM DU UM MR DA mer 119 11 5 121 IHL a 121 2 Portal Brame work ByolutiOnos uias ort PU Ip Pam oet p D Ern PD ME 122 12 1 Standard zaon EI ONS 4 ette pee Mon oerte el meti bU M eh State ef t Oh ef 122 12 1 1 Consequences for not having a standard sssee 122 12 02 Jay based POr CAF us oco bet etre et op Reto a boe buie Ute a sp UE 122 12 15 AVeDoServices POLIS eod ovi a an E dme i t 123 12 1 4 Possible features included in the standardizations sssssssssss 126 17215 C OBSCQUEHE Silicate sheer Dettet ae cech te e decr orsa varied tet 128 12 1 6 Potential DITHIeUlPleS eseman a od fett tts be od tfta me fut ende tas 129 2 17 AMendorDIVersrfICatlOll isusstetdueste o ee Qe tubi pac E aq oat ias 130 12 Enterprise Operating SyS Cienan eo tou deut dv o ide us eee 131 12 3 Other Technologle So
168. ith different numbers of columns and different widths of the columns There is for example Single column Single Row Two columns 25 75 and Three columns 25 50 25 One apparent problem is that there 1s no correlation between the sizes of the portlets and the column width This means that 1f the user place a very wide portlet into a narrow column the rendered page will potentially be much wider than the browser window in effect ruining the workbench Multi markup and Capabilities Jetspeed 1s multi markup language aware and can output its content in both HTML and WML There is a concept of a capability map associated with the connected client This concerns both which mime types the browser supports and which capabilities it has Capabilities include whether it can handle frames forms images Javascript tables and so on 42 Modular Development Frameworks for Corporate Portals a Literature Review 4 http www bluesunrise com jetspeed portal template Customize Microsoft Internet Explorer Sele File Edit View Favorites Tools Help Qsak 5 ix e fa Search p Favorites GM Media J et SD Bm Welcome to Jetspeed Endre stolevik Customize HTML WAL Edit account endre4 Lice Customize pane Documentation WML Add portlet API Layout j Colors 9 Stock Portfolio 9 Stocks 9 MyWeather Apply Cancel ab Internet Figure 11 WML customization Notice the two customizat
169. ivered as a MessageEvent on the receiving side implying that the receiving portlet must implement the message event listener interface as described above The concept of messaging 1s an analogy to the nter Process Communication concept that is found in most operating system a process may send information to another process using some defined means 10 7 State Persistence Preferences and Configuration An ordinary web application 1s usually using the URL line to keep track of which page the user is viewing thereby providing the current state of the user much like a state machine transition table In addition parameters kept in the URL can be used to for example keep the id of the active customer or the currently highlighted item in a list Combined these variables comprise the state of the user s experience If this start to complicate and too many things should be remembered between each invocation of the application a Session system can be utilized This 1s a store of named values which is kept in the server s memory or on disk between invocations from the client s browser The user is uniquely identified to his specific set of session variables by means of a Cookie or by having the URL rewritten to include the unique ID specifying the user s session However the fact that a portal workbench most often contains several portlets again gives rise to challenges compared to full screen applications Persistence refers to state variable
170. ix B Modular Development Frameworks for Corporate Portals a Literature Review 5 Corporate Portals Explained Corporate Portals or Enterprise Information Portals is a new concept in advanced intranet solutions Shilakes and Tylman 1998 two industry analysts working for Merrill Lynch coined the term Enterprise Information Portal in their business report dated 16 of November 1998 and thereby defined this new investment space They define such a system as Enterprise information portals are applications that enable companies to unlock internally and externally stored information and provide users a single gateway to personalized information needed to make informed business decisions In the same report the authors further consider enterprise information portals as an amalgamation of software applications that consolidate manage analyze and distribute information across and outside of an enterprise including business intelligence content management data warehouse and mart and data management applications Several terms and definitions are used frequently Both vendors and analysts attempts to give their own view or nuance to the different terms in use or coin new terms Firestone 1999 have done a survey of the different terms and definitions and states that the process of definition is a political business an attempt to persuade the Investment IT and ultimately the user community to de
171. izing its internal user database with the external sources This 1s done using a set of components called Authentication Source Providers which are configured to regularly update the internal user system with newly added users from the external source These new users can be given a default profile upon import However the Oracle Portal uses the Oracle Internet Directory as its repository for user and group definitions The user and group structure may be administered through the built in administration interface embedded in the portal or using the administration tools and APIs delivered with the directory system 8 5 Preinstalled Modules Several systems are preconfigured with a set of modules Popular are the inclusion of some content management system essential to any portal system In addition system taxonomy and searching functionality 1s often included Epicentric uses an external system for its searching facilities the Inktomi Enterprise Search engine This is installed with the portal Plumtree does also use an external system for searching the Verity search engine 100 Modular Development Frameworks for Corporate Portals a Literature Review 9 Framework Concepts This chapter summarizes and discusses the framework concepts obtained from the preceding analyses Several framework concepts are already mentioned in Chapter 5 3 Functional Components of the Corporate Portal The reason for including some of th
172. ks for Corporate Portals a Literature Review This event style of programming is similar to the one use in the Java Foundation Classes and makes developing portlets similar to developing any ordinary Java based application with a graphical user interface Direct Access to output stream All the service methods that let the portlet output anything is providing direct access to the output stream This is a very simple and powerful abstraction However if one portlet crashes or delivers faulty markup the whole page 1s affected This 1s a volatile solution where each portlet must work perfectly to enable the portal to function properly User Abstraction Object From the PortletRequest object passed with the invocation of any rendering methods the portlet developer may get hold of an object representing the currently authenticated user The User object contains information about the user like the nickname the full name the last login time and the user s ID Multi Markup The API supports multiple markup types Each portlets tell the portlet server which markups they provide in the portlet deployment descriptor This only makes the different portlets available to be configured onto the workbenches for the different user agents It is up to the portlet to actually check which client that 1s connected or which markup the connected client supports by querying the PortletRequest object and then supply that markup Configuration an
173. l Products J Choose a City Region O Sem Search the Internet Yahoo White Pages Saard En mx First Name Last Name required City Town State _ Online Help Efa ty ix Learn about the things you can do on the Plumtree Corporate Portal d My Pages cA ae X Communities z amp l Figure 30 Screenshot from Plumtree Portal from demo site Plumtree 7 6 1 Architecture and Architectural Features The server is only available for the Windows NT 2000 and the Sun Solaris platforms This suggests that the lower levels of the architecture are programmed in some natively compiled language for example C or C and not Java as many other portal vendors have chosen The Plumtree portal system features a two tier server whose structure they call the Internet Architecture This 1s an interesting portlet rendering approach where the rendering of the portlet workbenches are split in two simultaneously working stages The portlets of Plumtree s architecture are called Gadget Web Services and are hosted on dedicated portlet servers Plumtree Gadget Servers Note though that this has nothing to do with the newer term Web Service whose technology is based on XML See discussion of this in Plumtree D E and Plumtree B Appendix A The portal server is called Plumtree Portal Server and serves as the hub in this architecture To render a w
174. lable servers running the same portlet then the portlet 1s not shown to the users When the server comes up again the portal server starts to use it again However the portal server itself seems to be a single point of failure Adaptability The Plumtree Wireless Device Server WDS and Internet Device Server IDS enables users to access specialized versions of their workbenches The portlet developer must tailor the output from the portlets according to which device that is connected The WDS currently only supports WAP phones synchronized Palm PDAs and RIM Blackberry pagers However the IDS is designed to accommodate for new products as they emerge The Plumtree system 1s available in eight languages All language specific strings are stored separately in XML files including help files Internally UNICODE is user for character representation Based on the browser s locale setting the output 1s converted to an appropriate character set The browser setting also decides other localization parameters such as date time and number formatting Conformance The portlet server is written in some platform native language and is only available for the Microsoft and Solaris platforms However the portlets may be written in multiple standard languages Plumtree supplies Gadget Development Kits for Active server Pages JavaServer Pages Java Servlets and Perl Scalability The administrator chooses whether a portlet should run on a shared port
175. le and loaded by the WebLogic Server s flow control 50 Modular Development Frameworks for Corporate Portals a Literature Review service The processors and presentations may if well coded be re used in other settings tying the events to different presentations or processors Architecture of the portal The portal is in effect simply one big webflow An overview over the entire flow is shown in Figure 15 2 Editor Vvebflow portal 7 777 Vt p cr o Tum DO Ja LI h Tu u puaa ih mA E m Ipe 3 iI E SS ee EE o e Lo ee ee ee CEE POTI TTD s l a aerea A eer rod E LZ i A d E IL dq d dM m E Ton a INN ji rs 0 imo cec e E E m r Figure 15 Overview over the portal Webflow Green rectangle is shown in Figure 14 The BEA portal consists of a set of presentation JSP files and set of processors which are tied together by a set of events In addition there is a system internal Java package com bea portal that contains the state handling framework of the portal some EJBs are also in action The major part of the portal logic lies in the central preProcessor and its helpers processors shown in Figure 14 All these processors end up in postProcessor which in turn send the user to the portal presentation node This last node consists of portal jsp the central portal view renderer This file in turn includes files that mak
176. lect AN C l Update gerat Auld to this Folder c heer filler Cmte _ Upload a fin Birne Lipkea Iritia tege tor uplaadad zanbant Dres irate m nare dut document d frante a nam EE E abre rmn Figure 25 Screenshot from Epicentric Portal Extended Content Management from Epicentric webpage 7 3 1 Architecture and Architectural Features Java 2 Enterprise Edition The Epicentric Foundation Server is built on Java technology and runs on several J2EE application servers Epicentric does not provide their own J2EE server and it is therefore important for them to make the user able to choose between the different J2EE server vendors They have tested their system on multiple vendors application servers databases and LDAP servers The list includes BEA WebLogic IBM WebSphere and Macromedia JRun for application server IBM DB2 Oracle s 81 Sybase and Microsoft s SOL Server for database and Netscape and iPlanet s 28 Epicentric Company Facts http www epicentric com company fact sheet jsp 60 Modular Development Frameworks for Corporate Portals a Literature Review Directory Server Novell eDirectory and Microsoft s Active Directory for the optional LDAP server By using the J2EE platform Epicentric instantly gains scalability by using a scalable J2EE server In addition some commercial J2EE servers provide for seamless fail over in case of application server or JVM crash BEA WebLog
177. lero 148 16 3 6 PIE aout sete icona he RT Ae el Enea ey ee DM 149 Modular Development Frameworks for Corporate Portals a Literature Review 3 Introduction The terms Corporate Portal and Enterprise Information Portal refer to a relatively new concept in the information technology business primarily relating to the management of corporate information and knowledge It is a genre of web based applications meant for users both internal and external to the corporation IT consultants and corporate portal vendors promise easy configurable access to all of the corporation s own internal information and knowledge along with information from external resources all in a structured easily comprehensible manner The popular web portals whose concepts were created by Yahoo with their MyYahoo Service http my yahoo com have heavily inspired the user interface for most corporate portals Requiring only a web browser as the front end to the system the idea 1s that the users can select which of multiple resources they would like to have on their web based desktops much like the windowed user interface of most modern operating systems The users can further configure these often called portlets to suit their information needs from each underlying information source Arguments similar to the ones given in favor for corporate portals were earlier used for corporate intranets the company internal web sites used to gather share a
178. les document repository the rest of the sales organization would probably benefit from knowing this The administrator could configure the portal system to send a notification or send the entire document in an email to all the sales representatives in the company 5 3 8 Users Groups Permissions and Roles By providing easy and direct access to vital company data powerful yet simple to employ security mechanism must be available White M 2000 Several vendors employ two different concepts to control access to the information and functions in the portal system Users Groups and Access Control Lists The concept of access control lists or ACLs are embedded in some form in most operating systems The idea is that every object in the system has attached a list of users that are granted different accesses to the object Access rights are different in different context but may include the standard rights like read write change and delete an element or object However in other contexts rights like grant access and customize might be more appropriate A user group is obviously a set of users A user group is often used to simplify access control or restrictions Instead of individually granting each user a right to some object the users can be put into a group This group can later be granted rights and each member of the group gets this right Roles and Permissions While rights are used to control access to different objects
179. let server alone on a physical server or assign several physical servers to one portlet If one portlet 1s used heavily the Plumtree system lets the administrator easily add resources to the portlet either by putting it one a dedicated server or if that 1s not enough assign multiple physical servers to it However again the portlet server itself seems to have the possibility of becoming a bottleneck 90 Modular Development Frameworks for Corporate Portals a Literature Review 8 Architecture and Architectural Features This chapter summarizes and discusses the architecture and architectural features obtained from the preceding analyses 8 1 High Level Architecture The highest level architecture of all of the analyzed systems is similar to the one shown in Figure 33 Workbench Wo nch Reques sponse Operating System HardWare Figure 33 High level Architectural Overview of Portal Systems 8 1 1 Portal System as Enterprise Operating System As can be seen from Figure 33 the portal 1s providing a system in which portlets may execute This concept resembles to a considerable degree a graphical operating system and the programs that are installed and is runs within it The portal system represents the operating system providing services to the programs running some of the most important being the user and group management facilities and user interface and window management systems The responsibilities
180. lets needs to have some data to work properly for example an email client needs the server username and password to be used at all This 1s usually called the configuration of the portlet More on this 1s provided in Chapter 10 7 State Persistence Preferences and Configuration Personalization The personalization refers to the concept of tailoring the user experience in accordance with who the user is As the BEA portal system analyzed included the most elaborate personalization system this will be used as a reference The BEA system includes a rich personalization module This module uses two concepts called characteristics and entitlements A characteristic 1s an administrator specified attribute of which each user has to be assigned a value For example the user s SkillLevel must be set to one of Low Medium or High An 101 Modular Development Frameworks for Corporate Portals a Literature Review entitlement is a property that is automatically assigned if the user meets a set of conditions set by the administrator Attributes that conditions may build upon include the user s characteristics groups that the user 1s assigned to the IP address the user connects from and the date and time Each of these attribute can be required to be an exact value or within some range of values The conditions may be logically or ed or and ed together and can thus form a complex set of requirements A system may con
181. level details e JavaDoc API documentation J All JSP files that are used to run the server are available Installed Yes WebLogic Portal 4 0 on WebLogic Server 6 1 SP2 Epicentric Product Epicentric Foundation Server Sole product Yes Type of e high level sales pitched type of documents documents e Architectural overview documents Installed No only available to partners IBM Product WebSphere Portal Sole product No full range of hardware and software Type of e Sales pitching documents documents e Portlet Development Guide e JavaDoc API documentation available for the older EN version 2 1 Installed No not available yet Version 4 1 Due to be released June no Modular Development Frameworks for Corporate Portals a Literature Review Oracle Product Oracle 91AS Portal sole product No Oracle is widely known for their extensive database solution and several enterprise applications built on this Type of e Good documentation both high level overview and low documents level details e JavaDoc API documentation Installed No Plumtree Product Plumtree Corporate Portal Sole product Yes Type of e high level sales pitched type of documents documents e Architectural overview documents Installed No only available to partners Table 2 The Selected Portal Framework Vendors 6 3 Analysis Many of the scientific papers and articles are referring to the different vendors portal systems referencing and giv
182. lity as the users can access and fix missing or erroneous data in an instant Finally Plumtree Plumtree G points out that a corporation increases their return on assets opening expensive enterprise applications to the broad audience for which they were originally deployed 5 2 0 Knowledge Management The terms information and knowledge go hand in hand however knowledge usually refers to something deeper than mere information According to Merriam Webster s Collegiate Dictionary knowledge is the fact or condition of knowing something with familiarity gained through experience or association Information is an essential tool from which to gain knowledge but does not constitute knowledge in itself EAI is not a new term It usually refers to the integration synchronization and communications between multiple enterprise applications Merriam Webster s is available online at http www m w com Accessed June 3 2002 16 Modular Development Frameworks for Corporate Portals a Literature Review Knowledge management is therefore a somewhat fuzzy affair but revolves around tools and techniques that help identify and map the intellectual assets existing in the corporation spread and increase the knowledge throughout the corporation and facilitate the individual in gaining knowledge The term corporate knowledge in essence refers to the routines methods and know how the company as a whole has
183. m es al a i 2 Figure 14 The BEA E Business Control Center EBCC showing a part of the portal Webflow The most important entities of a webflow are Presentation nodes Processor nodes and Events A presentation is a user view and is stored as a JSP file A processor is some Java class file that does business logic retrieving and storing data and taking decisions Events are fired from both presentations and processors An example follows A customer has some decision to take and his browser is showing him a screen with two buttons This view 1s presentationX which happens to be the start point of a webflow The customer clicks the button1 thus invoking the buttonl clicked event This event is tied by the webflow to processorA thereby transferring control to this piece of Java code If the customer clicked button2 the button2 clicked event would be fired thus giving some other processor the control ProcessorA might decide based on some values from a database whether it should fire event customer WellOff or customer BadFinances These events are tied to presentation2A or presentation2B respectively giving the customer a new view Using these features the developer can construct large and complex web applications freeing him from the burden of coding the transitional logic The developer may instead use the graphical tool in the E Business Control Center to design the flow The flow is stored as an XML fi
184. marized and discussed Finally part four attempts at predicting how the development of corporate frameworks will evolve over the next few years Given the recent initiation of standardization efforts aimed at corporate portals and taking into consideration the significance of these efforts to the commissioners of the thesis it was furthermore decided to investigate these efforts and evaluate the implications they may potentially have for the corporate software industry The thesis concludes that a further dissemination of corporate portals and particularly a standardization of corporate portal frameworks may in the longer term potentially change the way in which small and large corporations employ information technology Corporate portals may be viewed as a new type of corporation wide operating system By installing a productivity or enterprise application on the corporate portal all of the corporation s employees will relative to their corporate role have instant access to all of the application s features Modular Development Frameworks for Corporate Portals a Literature Review 2 Table of contents li SUNNA c5005 saoatloavecas colcne aedmoneecn UU eanwaes ase M eBUp Dep Opa I daa noaan plaster ieomsacnantinetaaneaseceaconns l 2 OKRO ONEI S ood tno E eM RCM IN M EM LI KE 2 D rodic OH cuoc hant ML MI D IM I DK MI M MDC Ut EE EE 5 Sell IMO SNC 6 po CONS terns ae ees estas eee ae sa ite ee es 6 S MEI IUIS 8 gt Corpo
185. modular type of framework for portal development It is modular in the sense that each portlet 1s a separate independent part of the system enabling corporations to assemble and develop the functionality needed in a piecewise and gradual manner These extendable systems provide a host of different features for extending and configuring the product for the administrator or programmer They are all very different though even the basic architecture of the systems varies considerably from product to product Modular Development Frameworks for Corporate Portals a Literature Review 3 1 Motivation CoreTrek is a relatively new company with headquarters in Sandnes Norway It was founded in 1999 by a group of investors from the Hanabryggene Technology Centre One of their earlier projects was of such a scale that the project manager decided to make a foundation on which to build the rest of the project The aforementioned website MyYahoo and Netscape s Netcenter http my netscape com inspired this foundation Initially meant as a small platform for this one project it was quickly realized that the direction in which this project was heading could give benefits for other projects as well CoreTrek divided the project into two separate projects one that focused on the application and one that focused on the foundation itself This would enable the programmers to develop the foundation further tending to needs from multiple projects After
186. much more interactivity on the client side As an example a seller could let the customers install an application in which they graphically could check out the merchandise and for example doing calculations of dimensions When the customers have found the item they were looking for an order can be placed directly in the same application The application would contact the seller s server accessing a web service in which the order was placed giving instant order confirmation to the customer The company objectBOX have developed such a product the INSISO webtop obiectBOX http www objectbox com INSISO Webtop http www objectbox com eng Products webtop shtml INSISO demo installation http www insiso com 2154 Modular Development Frameworks for Corporate Portals a Literature Review 13 Conclusions The objective of this thesis was to investigate the functionality of corporate portal frameworks in particular what such systems provide in terms of functional components architecture and architectural features and what concepts and features they include The thesis furthermore aimed at predicting how portal frameworks are likely to evolve over the next few years The findings of the study suggest that different frameworks often have similar concepts and features due to the portal concepts that heavily guide the overall function of the portal However the study also observed significant differences Architectures are rarely
187. n degree this 1s also true for the Jetspeed system where Turbine provides for Pages Actions and similar constructs and Jetspeed extends this approach to a customizable workbench using the same mechanisms In contrast other vendors seem to view the portal systems as an entirely new concept demanding a new environment The systems from by Plumtree Epicentric IBM and Oracle resemble new operating systems The portlets are a new entity with its own life The portal paradigm is not only about the assembling of a view but is addition a new programming paradigm where new thinking must be employed The system from IBM has taken this thinking to the fullest extent employing a new stand alone API on which the portlets are programmed This API can potentially be implemented by other vendors enabling the portlets to run on other portal servers than IBM s 8 1 3 One or Two tier Rendering since multiple portlets exist as rendered windows on single web page all of the portlets and their containing windows must actually be rendered for each action the user does There are two different approaches to this operation It is important to note that this discussion only relates to how the portlets themselves are executed and not to whether a portlet must consult one or more external tiers to fetch the data used to generate the content in the portlet One tier rendering In these systems one server 1s both working as the portal engine and the envi
188. n he really needs In addition some information might not be desirable to give to the user right away e g contact information like telephone numbers a company might prefer that web visitors should use some contact form on the website instead 25 Modular Development Frameworks for Corporate Portals a Literature Review 5 3 Functional Components of the Corporate Portal Typically several functional components are available from within a corporate portal system This section will list and discuss some important elements that are common to many portals The following list is mainly compiled from PortalsCommunity 2002 Colin White 2001 and McDonough 2001 Eckerson 1999 has defined 15 requirements for a corporate portal some of which are applicable here and have therefore been included The components described here are of a generic nature some of which have previously existed in the same or similar forms on different systems 5 3 1 Taxonomy and Directory A taxonomy is a structured view of all the corporation s documents and information It is often set up as a directory with a directory structure much like the file system of most operating system The folders and subfolders hold different kinds of entries though and thereby work as a classification tree or hierarchy The idea is to enable access to all information in an enterprise through browsing and searching this directory structure Some systems make use of element pl
189. n the user clicks some portlet link or submits some data the portal server translates this to an action that 1s invoked on the remote portlet The parameters are submitted along with the action id on which the remote portlet acts It is important to note that portals based on such web services portlet are not bound to be implemented in any specific language This can be seen by the already existing portals using a similar approach one most likely written in a natively compiled language Plumtree another 1s using a hybrid between native compilation and Java Oracle with their application server and J2EE environment while the third 1s written entirely on the J2EE platform Epicentric J2EE platform using Modular Web Services 125 Modular Development Frameworks for Corporate Portals a Literature Review WSRP and JSR 168 Synergies A potential exist for synergies between the web services portlet and the Java Portlet API standard These standards can potentially be made in such a fashion that a portlet developed in the Java API can transparently be made into a web services remote portlet by simply configuring it as remote The IBM presentation to WSRP submissions points out such a possibility IBM WSRP WSRP as does the JSR 168 presentation The JSR 168 s charter mentions It is an important goal that the design of the Portlet specification would allow implementations to support remote Portlet execution As mentioned the c
190. nagement system rpm Roles and permissions A portlet being it a web service portlet or an API based portlet should be able to define multiple permissions associated with its functionality The administrator will use the roles editor to include the permissions defined by the application into the different roles defined in the portal or possibly create a new set of roles to handle these new permissions This is adopted in the Apache Jetspeed system The security level system of Oracle is a crude implementation of the same idea Standard portlet sizes One fact that seems to be neglected by all systems 1s the reality that the strict layout defined in most portlet system to a large degree confines the amount of information that can fit into a single portlet Specifically is this important regarding the width of the portlet as the typical small portlets for example cannot contain several input fields horizontally A set of portlet sizes should be defined so that a portlet can be assured that its content will fit into the column in which it 1s placed The portal would not let a user place a medium portlet into a small column as this would destroy the layout Another way of doing this especially regarding portable small devices is to enable the portlet to know how large the screen size the attached device have for example in characters or pixels Internationalization The apparent lack of focus on internationalization must be ad
191. nal result might deviate quite some from the IBM API 7 5 Oracle Oracle Portal Oracle boasts to be the world s largest enterprise software company providing enterprise software to the world s largest and most successful businesses With 2001 revenues exceeding 10 8 billion the software giant are used by 98 of the Fortune 100 companies The company has more than 42 000 employees The product line includes database application servers application development tools enterprise business applications and decision support systems On their The Oracle Story page the business idea that Oracle was founded on is explained Twenty five years ago the Oracle Chairman and CEO Lawrence J Ellison came across a description of a relational database prototype He saw the importance and possibilities that lay in this technology and realized that no company had committed to commercializing this type of system On these grounds he founded the successful company in 1977 with two co founders Bob Miner and Ed Oats In 1995 Oracle decided to commit to Java and 1n 1997 they began to implement J2EE standards throughout their product line Oracle have made a document entitled J2EE and Microsoft NET Oracle B where they reason that open standards portability and choice weighs in favor for J2EE compared to the one vendor proprietary approach of Microsoft NET About Oracle http www oracle com corporate The Oracle
192. nd distribute information and knowledge However today many corporations are faced with a multitude of corporate intranets Each of them supports different aspects of the corporation s information needs e g a document intranet a directory of often used files and forms and several intranets that web enable information to and from the underlying systems This jungle of information sources might just create yet another informational and navigational overload The corporate portal on the other hand offers a one stop single point of access resource where all corporate information is aggregated filtered through a role and access control system and finally personalized according to the user s preferences and job situation Lately most of the computer software vendors have delivered their version and vision of a corporate portal IntranetFocus IntranetFocus 2002 have identified over 70 vendors This list includes the software giants like IBM Oracle SAP and Microsoft but also a number of companies that were born with this market Several of these vendors have very specialized portals with a preconfigured set of portlets often interfacing to only one or a specific set of back end systems Others are much more configurable or preferably programmable providing means for extending the system with new portlets or extending the integration by developing new connectors towards underlying systems This latter type of portal systems provides for a
193. ndard does not mention scalability or any similar term as a characteristic or sub characteristic This 1s the capability of the software to scale or grow with increased usage both in number of users and the utilization of the product from the existing users A related characteristic efficiency is defined as The capability of the software to provide the required performance relative to the amount of resources used under stated conditions or rather how much use one get per resource This characteristic does not encompass the need for a software product to be able to scale If a corporation 1s expecting large growth in the near future it is not interesting whether the product is efficient but whether it Scalability for server products is most often achieved by making the server software capable of handling multiple physical server resources 138 Modular Development Frameworks for Corporate Portals a Literature Review can handle increasing load As this 1s an important aspect of a portal product this is a characteristic 1s used in the vendor analysis Usability with its sub characteristics understandability learnability operability and likability 1s used in several of the arguments for using corporate portals The user understands the concepts used in the portal and it is easy to learn and operate the system This is mostly because of the familiar user interface of a web browser and the concepts of windows loaned
194. ndatory workbenches and make configurations that locks down a set of portlets to a workbench prohibiting the user to remove them This separation of the content inside of the portlets and the frame which surrounds the portlet including title bar window control buttons and similar makes the use of themes easy A theme includes the design of the portlet frame colors and background of the workbench and the navigation bar By using Cascading Style Sheets CSS and a strict convention of how to format the content of the portlets one can also change the fonts sizes and colors of the content with the theme Thereby one can change the entire ook and feel of the portal by merely choosing another theme This theme selection may be user selectable with a default and the administrator might be empowered to lock down a selection for the users 5 2 Corporate Portal Arguments and Requirements Every vendor and analyst has their set of arguments for how corporate portals can make a corporation run more efficient to be more productive and gain a competitive advantage One ends up with a variety of arguments for the existence of these systems A representative selection of these is presented in the following sections These arguments lead to several requirements that a portal system should fulfill Several portal modules and functional elements that accomplish these requirements a pan Modular Development Frameworks for Corporate Portals a Lit
195. ness before inclusion None of the vendors does however elaborate on this possibility but this has been discussed on the Apache Jetspeed mailing lists during the portlet API discussions 117 Modular Development Frameworks for Corporate Portals a Literature Review The Plumtree documentation is the only one mentioning this type of error catching If a portlet crashes on a Plumtree system the portlet is taken out of service If the system is set up with multiple servers per portlet then the portal server can fail over to another server that is running the same portlet The J2EE systems from the commercial vendors are also often fault tolerant 1n that it can have fail over capabilities This means that the system is set up in a clustered fashion where several J2EE servers are working in unison If one of the servers fails this 1s picked up by the remaining servers Depending on the configuration this can be made to happen totally transparent to the connected users Recoverability and Availability since the portal will be used by the entire corporation centralizing much of the enterprise application usage through the portal it 1s imperative that the system 1s available at all times and that 1t can recover fast and well in case of failure Still only Plumtree specifically mentions recovery and availability in their portal documentation Plumtree lets administrators run their portlets on multiple servers If one of the portlet serve
196. ngst partners so that the best suited partner can take care of the customer relationship Joint selling opportunities and strategies can be discussed and acted upon Forecasts can furthermore be collected and analyzed so that a more accurate picture of expected revenue can be formed Partners are integrating and reselling the corporation s products and services thus gaining considerable insights in the features and values of the product In addition the partners customers will also give product feedback and suggestions The partners issues and enhancement suggestion can thus be very valuable to the corporation filtering and condensing their customers feedback in addition to the partners own experiences Technical information and training may be administered from the portal system The corporation might have a knowledge base in which they give the partners intimate JA Modular Development Frameworks for Corporate Portals a Literature Review access The partners may join the internal discussion lists and issues tracking system and get to know product release schedules and given insider information Web Visitors When the corporation has a presence on the internet two more entities can be added to the concept of the extended enterprise the anonymous web visitors and the registered web visitors These are people that are browsing the corporation s internet site looking for some kind of information or simply check
197. nly one as the other implementations employ application level user authentication mechanism The Turbine Jetspeed teams reason that container managed security can not easily be managed from within the application The idea with container managed security is that some container specific method for authentication 1s employed for example a database or LDAP backed mechanisms There 1s however no defined API relating to how to control the authentication mechanism s store of users nor 1s there as standard set of features that should be embedded within the store for example group or department membership This limits the applications flexibility relating the dynamic editing of existing accounts and creation of new accounts for example by invitations as in the Plumtree solution In addition the lack of a standard group membership solution severely restricts the creation of expressive access control systems Servlets and JSPs vs Other APIs The BEA solution exclusively uses recursive invocations of JSPs to render their portlets and does in addition use a set of Enterprise Java Beans The API that IBM used in their 1 2 and 2 1 version of the WebSphere Portal was a stand alone API developed in conjunction with Apache Jetspeed However in their version 4 1 IBM decided to rely on the Servlet API by making the Portlet interface directly extend the Servlet interface Both IBM and BEA s solution place an extensive use of the hosting J2EE environment
198. ns which meet stated and implied needs when the software 1s used under specified conditions Interoperability The capability of the software to interact with one or more specified systems NOTE Interoperability is used in place of compatibility in order to avoid possible ambiguity with replaceability Security The capability of the software to prevent unintended access and resist deliberate attacks intended to gain unauthorized access to confidential information or to make unauthorized modifications to information or to the program so as to provide the attacker with some advantage or so as to deny service to legitimate users NOTE This also applies to data in transmission 14 1 2 Reliability The capability of the software to maintain the level of performance of the system when used under specified conditions Fault tolerance The capability of the software to maintain a specified level of performance in cases of software faults or of infringement of its specified interface NOTE The specified level of performance may include fail safe capability Recoverability The capability of the software to re establish its level of performance and recover the data directly affected in the case of a failure Availability The capability of the software to be in a state to perform a required function at a given point in time under stated conditions of use NOTES 1 Following a failure a software product will sometimes be down for a certa
199. nt types called stateless statefull and entity beans The statefull type is enabled by the container to automatically store their state to a persistent storage for example a RDBMS An enterprise application may contain multiple web applications and multiple enterprise Java beans The web applications may communicate with these shared components Such beans thereby provide means for sharing services between the different web applications e Deployment descriptors are XML files describing the different elements of the enterprise application There are several different deployment descriptors for different elements of the enterprise application each containing extensive amount of data and meta data for the described elements There are deployment descriptors for the entire enterprise application each contained web application and for each enterprise java bean Information included is the naming of the elements URLs used resources needed parameters to the 75 J2EE BluePrints Design Patterns Model View Controller http java sun com blueprints patterns 2ee patterns model view controller Accessed June 4 2002 Java Pet Store Architectural Overview JSP MVC http Java sun com blueprints code psl l archoverview html Accessed June 4 2002 6 PHP http www php net ASP Microsoft s Active ServerPages mod perl http perl apache org and JSP are all code within HTML systems For example WebMacro http www webmacro org Ap
200. nt Frameworks for Corporate Portals a Literature Review 6 Corporate Portal Framework Vendor Analysis The following chapters consist of a review of what functionality some prominent modular development frameworks for corporate portals are giving today The analysis is carried out by doing an analysis of selected corporate portal frameworks followed by a summarization and discussion of these frameworks features and concepts 6 1 The Need for a Portal Framework The need for a corporate portal development framework is stressed by Colin White 2001 By supporting a combination of the bottom up and top down approaches for developing information technology solutions he argues that a federated portal framework gives the best combination of flexibility and totality Bottom up development implies that each corporate unit for example each group or department may develop their own portal solutions tending to their specific needs This gives great flexibility and ideas and issues can be tended to quickly However multiple installations lead to increased administrative costs and overhead In addition the corporation s global needs are difficult to tend to as the corporation s employees are scattered about on their different portal systems The top down approach is at the other extreme where developers surveys every need in the corporation and then develops one large monolithic solution This gives a system that can take the corporation as
201. o notice that the PortletSet and PortletControl are subinterfaces of Portlet This means that in every position one would expect a portlet one may instead insert a new PortletSet and have a set of portlets shown Thus as mentioned earlier one may configure a hierarchy of workbenches within each other The upper entity in this hierarchy 1s always a paned PortletController thus constituting the workbenches of the system The portlet developers use a special link reference generator to form a reference to the portlet thus being able to uniquely identify the portlet and send parameters to it from the browser regardless of its position in the hierarchy Several abstract classes are defined for each of these interfaces These classes provide a barebones implementation of the interface thus making the programming of a portlet easier as most methods already are implemented in the abstract class This API is tied very closely to three frameworks Turbine Jetspeed and Element Construction Set ECS The ECS toolkit is a set of code that enables a developer to code programmatically a HTML document by making and assembling objects referencing HTML tags like Body Header and Center in a structured fashion The link between the portlet API and ECS is that the main content generating method in the Portlet interface getContent 1s expected to return an ECS element This dependency 1s largely deprecated and is supposed to be taken away shortly Apache A
202. ocol over a TCP connection The Plumtree system uses a set of HTTP headers to pass control information and the ordinary HTTP protocol to pass data The Oracle system uses SOAP over HTTP for both control and data This method is shown in Figure 35 Comms API Portlets 9 Portlet A d Workbench Portal Comms a m e dii o Oe ol Portlet C 5 l Logical Server running on Single 9 d i or Clustered Physical Server I NN r ES Comms API Portlets Workbench i i ee Q3 CD Portlet B i z code Logical Server running on Single or Clustered Physical Server Logical Server running on Single or Clustered Physical Server Figure 35 Two tier sequential rendering An enormous advantage to the two tier approach is that the portlets does not necessarily need to be programmed in the same language as the portal server Since the communication occurs over standard network connections using standard HTTP any programming language on any system can be employed to write portlets Plumtree supplies Gadget Development Kits for Microsoft s Active Server Pages Java ServerPages and the programming language Perl Oracle has made a Portlet Development Kits for Java and for their proprietary PL SQL database language In addition th
203. of a portal system 1s remarkably similar to the responsibilities of an operating system some are mentioned in the following list User interfacing User management Data source management Running and scheduling of programs multi tasking Inter process communication 9 Modular Development Frameworks for Corporate Portals a Literature Review The portlets are representing the programs running within the operating system The portlets can execute independent of each other and the user may interact with each specific portlet without the other portlets being interfered with By enabling the portal to have portlet applications easily installed and managed by the portal administrator or administrators the portal system in effect becomes an enterprise wide operating system 8 1 2 Architectural Standpoint Webpage Assembly or Operating System While analyzing the different systems an impression of two different architectural standpoints arises On one hand it can seem like some vendors have understood the portal paradigm as an interesting new way of assembling a web page customizable by the user The portal concept is merely an evolvement from the vendors existing architecture For example the BEA portal solution use BEA s existing Webflow system in conjunction with an extensive recursive inclusion of different JSP files to assemble a set of customized views The system does not provide for any user specified pages To a certai
204. ogy stacks onto the customers 135 Modular Development Frameworks for Corporate Portals a Literature Review 14 Appendix A Definitions used from ISO IEC 9261 1 The two standards bodies the International Organisation for Standardisation ISO and the International Electrotechnical Commission IEC has 1n the field of information technology prepared a Joint Technical Committee called ISO IEC JTC1 Information Technology This committee prepared the standard ISO IEC 9261 Information Technology Software quality characteristics and metrics Part 1 of this standard is Quality characteristics and sub characteristics and some definitions from this part are used in this thesis The standard s focus is towards assessing a software product s usability in relation to a specific use or usage scenario This is especially obvious in the fact that all the characteristics and sub characteristics defined in the standard eventually leads up to a quality model called Quality in use The scope of this thesis is to assess a portal framework s functionality as defined in Chapter 3 Introduction and Chapter 4 Definitions and it shall specifically not assess whether the corporate portal fulfills its role as a knowledge management product or similar usage scenarios Accuracy Suitability Functionality Interoperability Compliance Maturity Fault Tolerance
205. om The company is called a Subscriber of the portal when hosted in this way A setup script facilitates the instantiation of a new portal on an already existing installation This makes an administrator able to setup such a subscription account in the matter of minutes instead of the hours needed installing a full portal system The script takes care of all the initial data entries in the database and authentication system and includes the setup of default portal pages 7 5 3 Framework features Portlet Development Oracle s portal system enables developers to create portlets in three different ways e Declarative The portal enables the developer to create portlets using a wizard driven declarative interface Such portlets may contain content published through the portal content management system There are also wizards for building forms 80 Modular Development Frameworks for Corporate Portals a Literature Review reports charts and other data driven portlets that may communicate directly with the Oracle database as well as other databases e Programmatic By use of the Portlet Development Kit a developer can program portlets in PL SQL Java and other web enabled development environements e Oracle Tools The Oracle Reports 91 Oracle Forms 91 Oracle Discoverer 91 and JDeveloper are all integrated with the portal through the use of Single Sign on and automated features and wizards for creating portlets Portlet D
206. om full applications like calendaring and sales automation systems consisting of multiple portlets to small utility modules for example a single portlet news headlines fetcher e Portal product portal system and portal refers to a corporate portal system except when otherwise specified e Portlet refers to a piece of a workbench It often remebles a window from most modern operating systems and contains for example close and minimize buttons to control the visibility of the portlet Portlets are sometimes self contained acting like one small program in itself but are often used in conjunction with other portlets The set of portlets then forms a module e Workbench refers to the users view of the portal Portlets populate the workbench and it often resembles a desktop from most modern operating system Most portal system divides the workbench into several columns based on how the rendering of a web page is done This restricts the possible widths of a portlet to the widths of these columns e Physical Server is used when a distinction between the server software process and the physical processing unit machine is needed The physical server refers to the processing unit while server or logical server 1s used for the software process some terms from the standard ISO IEC 9126 Information Technology Software quality characteristics and metrics 1s used throughout this thesis and 1s listed and explained in Append
207. on 13 The client decodes the response and translates the return value back to the client s native language 14 The application now have the correct value Visual Web Services Web services enables two applications residing on different machines possibly on different architectures and programmed in different languages to communicate The Web Services concept does not have any functionality for a person to communicate with a Web service For example the application described in the last subsection still needs to be implemented as a full application on the client side even if its only job 1s to take a value from the user invoke a web service and display the returned value to the user If there was some markup language that could describe which elements a user interface for the web service should contain what operations that could be performed and which states 1t could be in a general visual web service client could be developed that displayed these elements and let the user choose the operation to invoke This is exactly what multiple standardization efforts are doing right now Compared with the two tier rendering approach used by Plumtree and Oracle this approach is very similar The Oracle solution indeed uses the Web services protocol SOAP to communicate between the portal server and the portlet server Standardization Efforts The XML standardization body Oasis has two standardization efforts running regarding visual
208. oncluded that Jetspeed was not mature enough for production release The 1 2 version was therefore bumped to 1 3 and retracted to an alpha status Amongst the current topics on the Jetspeed mailing list the first beta release of Jetspeed is discussed and is apparently soon to be released Testing shows that the Jetspeed system clearly is not suited for production environments The author s installation went smoothly Only a 1 3a2 distribution were available at the website and the CVS checkout did not compile but several of the features seem to be in a very early stage Some features are just non functional while other goes awry or crashes when used In addition the documentation is like with many open source projects scarce Developers are in general more interested in writing more code and new functionality than writing documentation This comes in addition to the fact that the developer sees the whole system as perfectly logical and easy to grasp while newcomers might have substantial problems with the extensiveness of it all Without any financial resources it is difficult to get someone to write proper documentation Jetspeed suffers from a serious lack of overview documents that explains how the different levels beneath works how the different entities connect and what the lifecycles and call patterns for the different entities are However the source is available but this is very low level making the high level overview understandin
209. ools and sales automation and customer relationship tools Enterprise Application Integration Software vendors will see an opportunity of making enterprise application integration portlet sets where a portal administrator simply buys and installs a portlet application tailored to the company s chosen enterprise application This will enable all of the company s staff to access the data contained in the enterprise information system This can already be seen with their enterprise class gadget suites and frameworks However if a portlet standard is established this will be a viable way for several companies In addition the enterprise application vendors will themselves make commonly used subsets of their system accessible from a set of portlets to increase the usability of their product This 1s highly interesting when a standard way of creating such applications 1s made available Web services portlet standardization will make this even easier as the enterprise application can be embedded with a web services server and publish its integration portlets by default The portlet administrator only needs to point his portal to the URL at which the services are published and instantly the enterprise application 1s made available to all employees Move Customer Portal over to Customer s Portal Another shift made possible by the web services portlets is that for example customer self service applications may be moved closer to the customer
210. or more persons It usually comes in one of two flavors The first one is a very direct communication form where each keystroke of the users is communicated to the other participant Comprehensive resource page on CSCW and Groupware http www usabilityfirst com groupware 19 Modular Development Frameworks for Corporate Portals a Literature Review instantly appearing on his screen This system appeared with the UNIX command talk The other type of system has lately been known as instant messaging and the concept is used in tools like Microsoft s Messenger and AOL s Instant Messenger Using these systems a user s message is not transmitted to the other parties until the enter key is pressed This is also a long known communication form popularized with the nternet Relay Chat system IRC e Messages are very similar to email except that they are delivered within the system itself This means that there 1s no delay between the sending and reception of a message making it somewhat similar to the instant messaging described above The messages are kept in folders in the same way as emails Notification of the reception of both messages makes fast responses to queries and questions possible The portal system may have provisions for integrating messages and emails in effect making the distinction disappear e Discussion forums or message boards are a messaging system where the message inbox 1s open to a group of users Th
211. ordinary web browsers However both of these markup languages come in different versions where the older versions usually support less features than the new ones In addition different browsers may support different features or have known bugs with some of their features as experienced for a long time with the Netscape and Internet Explorer fights 10 2 1 Multiple Markup Languages Support Plumtree Apache Jetspeed and IBM s systems support multiple markup languages specifically WML These vendors require the portlet to handle each type of markup There are two main issues with multiple devices and markups screen size and markup expressiveness The screen sizes vary considerably from for example 80x40 pixels monochrome on a WAP telephone to 1600x1200 pixels with true color on a computer screen The WML markup for WAP devices is completely different and supports fewer features than HTML for ordinary web browsers 106 Modular Development Frameworks for Corporate Portals a Literature Review Most supported is the online access of a mobile WAP telephone supporting the WML markup language In addition the Plumtree portal support synchronization systems like the one from AvantGo The synchronization scheme 1s directed towards static content and interactive services are not supported An interesting approach to this challenge 1s to make a device independent markup language for example using XML and transform this using some
212. orkbench the user s browser communicates with the portal server This server in turn figures out based on the user s layout of the workbench which portlets it needs to fetch Requests are sent out to each server hosting the relevant portlets asking them to render the portlets This is done in parallel using Plumtree s Massively Parallel Portal Engine MPPE If the portlet has enterprise application integration functionality the gadget server may be hosted on the same physical server as the enterprise application or it may be hosted on a separate physical server This makes the process three stage The portal server finally collects all the separate rendered portlets assembles the completed workbench and outputs it to the user This process is shown in Figure 31 Modular Development Frameworks for Corporate Portals a Literature Review I Workbench Mainframe Underlying layers HW and OS W bench ij Edel Server Servlet Engi Reque m JSP G e esponse A Request e Apache with mod perl EC mE S i rv e B ds Undergoes and 08 Figure 31 Plumtree Architecture Massively Parallel Portal Engine The communication between the portal server and the gadget web service server 1s done using ordinary HTTP requests over TCP IP This makes almost anything capable of being a gadget web service as long as it can read HTTP and reply using HTTP headers and HTML or
213. ormation of all Norwegian companies Fuiriiisiisiisisssiisisiiiisisiiiiiisiiiisii3i3 3333333 TICIGG 330233333323 33 2 13 32 32 3 3 32 32 323 33 33 3 3 0 3 33 33 33 323133332313 33 3331323 3332333 3331322 33322 32 3331222 33322 32 3331323 33 1333 3332323 33 13 32 33313 22 33 12 33 33313 22 33 33 32 33 31 32 33 32 32 33 33 33 33 33 32 32333 22 22 33 32 32 23 22 22 23 22 22 23 22 22 2 22 22 2 22 22 23 22 22 23 22 22 23 22 22 23 22 22 2 22 22 23 22 22 23 22 32 23 22 22 23 22 22 2 22 22 23 22 22 2 22 22 2 2 22 23 22 22 2 22 22 23 22 22 02 Table 1 Examples of internal and external information sources Many information sources are difficult to access known to or handled by only a few persons in the organization For a mundane example most companies need to focus on the customers who actually give them profitable business It would thereby be beneficial if all employees in the organization knew at all times who the 20 most profitable customers are This 1s most often not the case because usually only i Modular Development Frameworks for Corporate Portals a Literature Review fractions of the company have the necessary access to and knowledge of the accounting system where such information is stored Dias 2001 states the problem in the following way Most of the time this information 1s stored in computer hardware in a unorganized way spread in databases rendering access to relevant knowledge difficult and compromising employees prod
214. other NOTE The environment may include organizational hardware or software environment Adaptability The capability of the software to be modified for different specified environments without applying actions or means other than those provided for this purpose for the software considered NOTES 1 Adaptability includes the scalability of internal capacity e g screen fields tables transaction volumes report formats etc 2 Adaptability corresponds to suitability for individualization in ISO 9241 10 Conformance The capability of the software to adhere to standards or conventions relating to portability Replaceability The capability of the software to be used in place of other specified software in the environment of that software NOTES 1 Replaceability is used in place of compatibility in order to avoid possible ambiguity with interoperability 2 Replaceability does not imply that this software is able to replace the software under consideration 3 Replaceability may include attributes of both installability and adaptability The concept has been introduced as a sub characteristic of its own because of its importance 14 2 Comments e Several of the definitions includes the phrase under stated conditions of use or when used under specified conditions As this thesis does not explicitly specify usage conditions confer the scope of the thesis the conditions of use 1s set as any applicable e The sta
215. otocol SOAP Web services is a new technology XML itself was specified February 10 1998 while the protocols that make up the web services framework still are settling The W3C have initiated a Web Services Activity where The goal of the Web Services Activity is to develop a set of technologies in order to bring Web services to their full potential To illustrate the Web Services concept a standard example of a currency exchange application utilizing a web service will be described Client Application Web Services Web Services Currency Conversion Service Client Server Implementation Implementation 9100 NOK gt USD WebServices URL i http Av bservice convert com currencyConstruct SOA soad HTTP e Request quest Invocation Method convertCurrency L Arguments 1 String NOK 2 String USD 3 Float 100 00 10 Returned value 12 5506 Convert E Construct OAP Response Figure 38 Example of currency conversion using Web Service Note this is an abstraction of how a client communicates with a web service and is not meant to represent the actual messages passed ied and convert Method convertCurrency Arguments 1 String fromCurrency 2 String toCurrency 3 Float amount Convert a UG on HTTP Response 12100 NOK 12 5506 USD 1 The application needs
216. otocol this called Web Services Remote Protocol WSRP Epicentric have joined this working group submitting their work as a contribution to the new standard Oasis is an international not for profit consortium that designs and develops industry standard specifications for interoperability based on XML Website http www oasis open org 64 Modular Development Frameworks for Corporate Portals a Literature Review Visual creation of modules Epicentric Foundation Builder This is a module that help business users make Epicentric modules Epi D It has several tools that make the development and generation of modules a more visual experience Several wizards and other browser based tools leads the user through the design of the application Reports are made with the help from a query builder The users of the application can later filter and sort data within their personalized page Forms are built with functions like Add Button and Modify Input Field and data verification rules are built and applied to the form Remote resources may be leveraged using web services technology The application is generated and can be deployed into one or several of the portal sites residing on the server How complex applications the application builder can generate is not mentioned and it is most likely confined to relatively low complexity forms based applications with data entry and modification and querying of
217. owser initiated actions The rest of the entities are concerned with the creation of the web page s content and their relationship 1s shown in Figure 9 Figure 9 The relationship between the Page Layout Navigation and Screen entities Adapted from Turbine s website When a request comes in from the browser the turbine framework checks whether the user is logged in If not the login page is shown If yes the chain of events are as follows Turbine J2EE integration http jakarta apache org turbine turbine 2 j2ee integration html 2 Turbine Specification http jakarta apache org turbine turbine 2 fsd html 40 Modular Development Frameworks for Corporate Portals a Literature Review HTTP execute Execute Request P Turne Page E Servlet ORA A Execute Layout Screen Navigation A Execute Action HTTP Response Figure 10 Turbine event chain Adapted from Turbine s website The users request includes which screen the application should perform and what action should be performed If an action deems it necessary the screen that will be shown may be altered before passing on control After the action is invoked the resulting screen is requested for which layout should be used The returned layout is executed which in turn executes and includes the content of the navigations and the screen The rendering of the di
218. pache Jetspeed is built on Turbine and this feature is thus inherited The Turbine user object does also have accessors for such personal data and in addition features temporary and permanent storage for user values These storage features support state handling elaborated on in Chapter 10 7 State Persistence Preferences and Configuration By making available such an object the framework relieves the portlet developer from the burden of storing such common information The user object provides a platform for enabling common data about the user to be shared by all portlets Several frameworks provide a non authenticated user object if the user accessing the portal is unknown or not yet authenticated to the framework This enables the portal to be used by both authenticated and non authenticated users as the developer can program one portlet that will be shown to both types of users If some information requires authentication the developer can have the portlet check whether the current user object 1s the special non authenticated one or if the framework have provisions ask the user object whether it represents an authenticated valid user 10 2Multiple Markup Support and Client Capabilities several of the portal systems analyzed support multiple markup languages on different clients There are several aspects to multi client access Multiple markup languages must be supported for example WML for WAP mobile telephones and HTML for
219. pared with other information BEA states Customer information 1s one example of the type of information that often resides in multiple silos of information within the enterprise BEA E There might be a company record and several invoice records in the accounting system a customer record and multiple agreement records in the customer relationship management system several records in the support line system and probably even more records in other customer related systems By having all this information readily available when a customer contacts the company the employee will be able to provide customers with better service Business Intelligence and Decision Support Business intelligence 1s a term used by the data warehouse on line analytical processing OLAP and business reporting industries The idea is that a sizable company usually sits on enormous amounts of information that never get used These systems work by fetching data from multiple sources using so called connectors and adaptors that can access diverse data sources from main frames and legacy data to standard SQL based databases This is often done by scheduled batch processing for example every day or every hour The data is then cleaned by defining single units and unambiguous concepts for example ensure that all sales are in the same currency and a purchase is defined to be some specific event Thereafter the data is moved and arranged in a central data store
220. pers specifies a set of jsp files including the titlebar banner header portlet and footer In addition 1f the portlet supports the help and edit modes a jsp file for those modes must be supplied as well Usually the titlebar file 1s selected to be the system default as this supports all the necessary features like mode switching The number of modes natively supported by each portal system differs The combined list of modes are as follows e Minimized Only the portlets title bar is showing e Maximized The portlet is using the entire workbench e Edit The portlet is in a defined edit mode allowing the data to be changed by the user e Floating or detached The portlet is detached from the workbench and fills the entire area of a separate browser window The window markup is not drawn as the browser functions as the window e Help several systems natively support a help button on the window s frame opening a help screen in a new browser The edit mode and floating mode is the least supported modes The idea with the edit mode is that it helps the developer distinguish between when the user is supposed only to view data and when the user is allowed to edit the data For example the IBM system only allows the customization data to be changed if the portlet is in edit mode raising an exception if this is attempted in other modes The BEA system lets the developer assign different JSP files to the different modes 8 4 Configu
221. pment Frameworks for Corporate Portals a Literature Review 11 Software Quality Model Following is a brief analysis of how the different products as a whole relate to the chosen characteristics of the ISO IEC 9261 1 Software Quality Model confer Appendix A Definition used from ISO IEC 9261 1 Several of the elements beneath each characteristic were elaborated on in the preceding chapters and are therefore just mentioned briefly here 11 1 Functionality Interoperability One of the main arguments for a portal system 1s the ability to display from and gather data to underlying systems of diverse types Choosing only one technology Java is currently not a bad option as there are Java APIs for most any computer technology available Java enables connections to other URLs to databases and other resources communicating via most any protocol A portal system should also interoperate with underlying enterprise applications However this is not necessarily the portal server s responsibility but can be done by independent connectors that communicate with the application The enterprise application s functionality 1s exposed as an API Several enterprise applications already have some external API defined for some language In addition the J2EE Connector Architecture JSR 16 specifies a standard architecture for integrating Java applications with existing enterprise information systems thus providing a standard way of
222. pment Frameworks for Corporate Portals a Literature Review e WYSIWYG creation of menus and submenus enables the site administrator to create or edit the menu structure that users of the portal use to navigate through the site The menu items may reference a wide range of items including links to the different workbenches existing enterprise web pages and internet web pages e Unified Site Themes are the portal sites look and feel Visual elements of the Site Theme include portlet appearances footer header site controls and navigation blocks There 1s also a concept of a portal site s grid which 1s the physical layout of these other elements Export Import of Portal Site Configuration and Portal Components It is possible to export and import the configuration of entire portal sites using XML files as the configuration transport medium In addition also site components can be exported and imported The server console is used to access these features These functions makes backing up the portal s definition and configuration easy but also facilitates the development and staging of portals sites including portal sites that already are in production Staging 1s for example done by copying the live configuration to a new portal site possibly residing on another server This new site may be reconfigured and tested and then loaded into a staging server for final user testing Finally when the user groups are satisfied the configurat
223. portal system including the pages providers and database objects The user can locate a specific entity and may perform actions on that entity both operations constrained by the user s privileges to the entity in question Hosting Application Service Providers and Virtual Private Database A company s portal system can be hosted on a shared server that is hosting several other companies portals This is done by using Oracle91i database specific feature called Virtual Private Database This system adds one more dimension to the database s tables isolating the different companies data from each other while still using the same database tables This enables a hosting environment to keep several customers portals on one portal server and database installation instead of having one portal and one database for each customer This is a cost effective solution since a high number of portal servers and database servers would require a significant number of physical servers In addition the administration overhead of managing a great number of database and portal installations 1s greatly reduced In such an environment a user logs in with not only his username and password but must in addition supply the company name Alternatively the system can be configured to allow for Branded URLs which enable one company to access their portal at http portal companyA com while another company accesses their portal at http portal companyB c
224. products In addition the Epicentric and Plumtree system 1s not available for developer or evaluation download IBM s system 1s not available until June this year The Oracle system 1s available for download however the sheer size of the installation set three CDs for the database and an additional three CDs for the application server combined with the seemingly elaborate installation procedures made the installation difficult and it was thus decided against However the Apache Jetspeed and BEA s systems were available for download and was thus installed and tested Several of the vendors documents are of a very basic nature or intended for decision makers rather than software engineers Often there is a lack of proper API documentation and similar low level information about the frameworks programming environments This can potentially give the effect of missing some interesting features or concepts Table 2 includes a description of what kind of documentation that was found on the different vendors web sites Java 2 Enterprise Edition As it turned out most of the portal systems evaluated need some or the entire Java 2 Enterprise Edition environment to run on Some understanding of this standard will be essential for the following chapters A review is given in Appendix B Further division of the thesis Chapter 7 contains one subchapter for each vendor analyzed The subchapters are further divided into sections for architec
225. quiring little server performance can be hosted on a single server This flexibility enables the administrator to tune performance by adjusting the number of physical servers that host the different gadget web services adding physical servers to the heavy gadget web services e Fault tolerance If one gadget web service fails or crashes this affects only that gadget server The physical server can also crash merely disabling the portlets hosted on this server The portal engine notices this and disables the portlet server until the service recovers If the gadget web service is deployed on multiple servers the portal server will use these still working servers and eventually include the failed server when the service 1s restored e Security The gadget web services in effect isolates the enterprise application to which it integrates The gadget web service decides which functionality of the enterprise application 1s exposed By putting the enterprise application behind a firewall and opening up for HTTP connections between the portal server and the gadget server another layer of security 1s introduced denying direct access from the portal server to the enterprise application e Openness Plumtree s architecture is one of the most open portal systems around since the developer may choose with which HTTP aware language portlet programming should be done This is not judged as a conformance capability as there isn t an
226. r himself configure and manage the looks layout and pages visible in the portal It also includes any portlet specific configurations where the portlet s view 1s changed according to a user or group s preferences 6 Modular Development Frameworks for Corporate Portals a Literature Review A feature that definitely lacks from BEA s portal system is the ability for a user and group manager to make new portal pages Most other portal systems have a concept of MyPages and GroupPages In the WebLogic Portal the users and group administrators may only choose between pages already configured into the portal by the portal system administrator Personalization Personalization is similar to the customization in that it changes the view of the portal for a user or a group of users However where customization is an explicit process where a user or a group s administrator chooses what to see personalization is a more implicit process The view of a portal including which skins portal pages and portlets that is in use and which content the portlets are showing is changed according to properties of the logged in user A customer gets to se different pages portlets and content than a partner do and a good customer will get special offers which other customer do not get This 1s done using the personalization package BEA D This framework may be licensed separately but 1s included with the portal license Both a
227. r and a truly extensive documentation pack 45MB zipped is offered as a 30 day free trial download at their web site This proved invaluable as it gave good insights in how the portal operates in conjunction with the other components of the system 4 BEA Basic Portal Microsoft Internet Explorer SEE File Edit View Favorites Tools Help aw Address 4 amp http flocalhost 750 1 stockportal index jsp v Eo home f web misc Portal Tour Follow along step by step and create a user user groups assign administrative privileges add subtract and move portlets apply skins and more then log in here as the newly created user and see the personalized results eDocs e docs bea com Documentation for the e generation Portal Documentation Access all the BEA WebLogic Portal 4 0 documentation topics in BEA on line documentation amm UV vom avitel Aviteh Welcome to the Avitek example portal Use this simple portal as your sandbox for getting acquainted with BEA WebLogic Portal 4 0 Navigate among the tabs The portlets on this page lead to a variety of helpful resources Try out the simple portlets on the Web tab Finally the Misc tab leads to several purely generic portlets designed for your own content and experimentation The fast track for e commerce developers http developer bea com BEA Developer Center The BEA Developer Center is fast becoming a leading resourc
228. r own metrics both for the custom modules and for the framework itself Included in the Epicentric Foundation Server 1s several metrics both static and periodic The static measures include number of registered users pages and sites in the system The periodic measures include number of users using each module active users total page views front page views and maximum and minimum concurrent users These latter figures are all measured within some specified period 7 3 2 Framework concepts and features Portal Site Creation To help create and assemble new portal sites Epicentric provides several tools within their system e Site Creation Wizard walks the administrator through the steps required to deploy a new site These steps are Site info choose the name and the URL of the portal site Pages choose which Workbenches that should be available Modules add portlets to the selected workbenches Appearance apply a theme to the portal site Site finished preview Deploy Pod du e Shared components refer to portal components that may be shared and re used between multiple portal sites that reside on one portal server Shared components include modules pages themes and other user interface elements e Rapid Site Assembly allows administrators to build portals from repositories of pre built reusable components New portal sites may be developed and deployed within minutes instead of months 63 Modular Develo
229. rate POrlals E plained essa e otis E ese uai Qui um a ded und 10 Sol The Portal User Experience cono RUD d pcd ol ea eee 11 5 2 Corporate Portal Arguments and Requirements esee 12 S21 Make Information Accessible 22i e ERR e ote tendum 13 522 JEeduce InformaltiomOVerlaad oo sectetut tte adieu 14 32 Jnformation Ac ere canons die ti eto d EOM oS UR dis teda d eee en 15 5 2 4 Enter Data Enterprise Application Integration seee 15 Dd dEROWIedociMandPetefil s roo careat bera tos estrena obo nieve diae un deed in ubl eva dina ata 16 3 2 0 ZCOIISDOFLALEOTI S cio tod da MEME E M 19 522 JISGTHOLO NC COSS 006 onec osce e disdo titu tu mio iod uere tutto eto Pp Com uo Ao t Dont ume Fo ee Dum o AD 22 2 2 5 Inteerate the Extended Enterprise 125 52 iter doe Hetero ral abad aiea 23 5 3 Functional Components of the Corporate Portal cccccccccsssssesssssessesesseseeeeeens 26 Soult Farxomommay and Directory eco cette etos a ivelit od boite atas 26 5 3 2 Publishing and Content Document and File Management ssssss 26 WO DECIDE RT Oe NE 2 5 3 4 PDA integration and synchronization ccc cc cccccccceceeeeceeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeey 27 5 3 5 Workflow and Business Process Automation ccccccccecceccecececeeeeeeeeeeeeeeeeeeeeeeeeeees 28 530 Alernsand NOELIA TOTIS 4e sda a T 28 5 3 7 Push Information and Subscriptions sse 29 53 8
230. ration and User Management Most portal systems have some file based configuration details However web based interfaces are the norm for configuring most parts the systems The reason for this approach 1s that graphical user interface 1s much easier for most people to handle than text editing of properties files or XML files especially when the administrator 1s new to the technology 99 Modular Development Frameworks for Corporate Portals a Literature Review Configuration details include user and group management default workbench layouts and access control list editing for the different elements of the portal system and other administrative tasks For further discussion of this topic confer Chapters 9 5 Administration and Delegation and 10 4 Portal Creation Internal vs External User Management The user group and access control management of a portal system 1s a complex affair Authentication only refers to the accept or denial of a user s credentials This can be handled by any system that can store a username associated with a password However portal systems often rely on group memberships and comprehensive access descriptions for each user These details are part of the user s profile Connecting to for example an existing LDAP source usually only supports the authentication while the group memberships and access control lists must be handled by some internal means Plumtree handles this by synchron
231. rative tasks to multiple individuals The reasoning behind such functionality is that today s large corporations are so large and spread out that one administrator cannot handle all the necessary tasks and that locally situated administrator have better local control Several portal systems emphasize their ability to create multiple portals on the fly within one server These new portals can usually be administered by a dedicated administrator BEA has a distinct set of administration levels These are system portal and group administrator These levels go along with the distinct set of different portal levels The system administrator controls the entire enterprise application thus including all portal web applications contained within This level controls the creation of portal web applications and all levels beneath A portal web application 1s administrated by a portal administrator Within one portal one can create group portals These are subsets of the containing portal and are controlled by group administrators BEA uses explicit delegation A system administrator can create several portal and group administrators He can then grant the administration of one portal web application to a portal administrator and at the same time he can choose whether this administrator may delegate the same right further on This enables the system administrator to select a few portal administrators and enable these to further delegate the group adminis
232. remely lightweight and fast container In addition Oracle frequently mentions the JServ product from Apache which is a Servlet Container implementing the Servlet 2 1 standard This server 1s from Apache s side now deprecated in favor for the Tomcat line of servlet containers The Portal Server The portal 1s an integral part of the Oracle91 Application Server Judging from the Technical Overview white paper Oracle C the assembling of pages and portlets 1s done by a core portal engine which is built upon the OC4J The portal engine is thus a Java Servlet based system However it 1s tightly integrated with the other services in the application server suite Text based Configuration Files Much of Oracle s systems and subsystems use text based configuration files similar to how most of Unix systems are configured Several of Oracle s Application Server systems are derivates from Open Source projects specifically Apache Web Server and Apache Java JServ Oracle s newer OC4J 1s using the same configuration setup that Apache Tomcat is using making a developer from the open source community feel comfortable with the system Oracle also supports Apache Ant a Java building system Portlet Providers A portlet communicates with the portal via a Provider Oracle C E Each portlet must be connected to exactly one provider but one provider may contain multiple portlets The portlets of a provider exposes its underlying application or informat
233. rkbenches styles items and portlets Each element has its own access control list and privileges for accessing customizing and modifying the different elements are granted to users and groups In addition an administrator may delegate the management of the access control list for each object to the object s owner An 103 Modular Development Frameworks for Corporate Portals a Literature Review administrator may also grant global privileges to sub administrators on all objects of a given type 9 4 Modules and Portlet Applications Modules or Portlet Applications are a set of portlets that together form a functional unit Much as an application 1s installed on an operation system a portlet application is installed into the portal The portlets contained within the portlet application 1s configured by the administrator and is thus made available to all of the portal s users The old IBM system using the new Jetspeed API had a concept of a portlet application archive where an administrator could load and unload such packaged par files dynamically The new IBM portal uses the underlying J2EE environment s web application concept to contain a portlet application which places the burden of dynamical loading and unloading on this servlet container Oracle has a concept of remotely hosted Providers containing the actual portlet implementations The URLs to the location of these providers are configured while the system is
234. ronment in which the portlets are executing The control is alternated back and forth between the portal engine and the portlets on the workbenches to some degree resembling a multitasking operating system Passing of the parameters from the user and the portal engine and the return of output markup from the portlet 1s facilitated using method invocations directly on the portlets through the portlet interface This method is shown in Figure 34 and is used by all vendors except Plumtree and Oracle However the history behind Jetspeed and Turbine are actually the other way around where Turbine was extracted out from Jetspeed 509 Modular Development Frameworks for Corporate Portals a Literature Review Workbench Portal API Portlets PW y code 0 5 IO y Portlet B y code 8 7 Io I Workbench SE Portlet C code 0 a Logical Server running on Single or Clustered Physical Ser Figure 34 One tier sequential rendering Two tier rendering This approach relies on using multiple servers The logical portal server functions as a hub invoking the portlets code residing on other logical servers These portlet servers are usually residing on different physical servers as well Passing of parameters to the portlets and return of the output from the portlet is facilitated by some prot
235. roups The portal administrator may delegate ACL responsibility to object owners An administrator may also grant global privileges to sub administrators on all objects of a given type Administration of the Portal through the Portal The portal 1s itself fully portlet enabled and the portal 1s preconfigured with a set of pages and portlets for portal development and administration Here the users and groups may be managed The portal system have import and export features providing for staging and export of portal content This includes the page definitions security settings and all item and portlet content The administrator may export from one or several development servers and import the definitions onto the production site 79 Modular Development Frameworks for Corporate Portals a Literature Review The Oracle9i1 Application Server includes a system called the Oracle Enterprise Manager OEM to which the portal system is integrated Using the user interface of this system an administrator may monitor and maintain the data portal configuration files and services underlying the portal system This includes the HTTP mod pl sql and web cache services in addition to the servlet engine the portal database the single sign on system and the portlet provides Portal Navigator The portal navigator is per default available from the portal page banner It enables administrators and users to browse the different entities in the
236. rs The information needs for suppliers are in several ways the opposite from the customers A corporation would want their suppliers to open up their information so that it could check the suppliers inventory and make proactive ordering decisions In several industries typically the agricultural industry and other primary industries the suppliers supply to only one or a few corporations The corporation in question might not even be an independent organization in itself but rather a co operative for all the suppliers for example an agricultural co operative In such settings the suppliers are close to the employees group demanding access to both extraction and entering of data A farmer would for example want information on how many cows he has delivered so far this year and be able to order pick up for a new batch of chickens next week Partners Corporations are becoming more focused on their core competencies This makes a corporation dependent on a large and tight partner network from where to get the competencies that it lacks A corporation must be able to enter partnerships fast and efficient A good partner channel portal where a lot of information 1s being shared would enable both partners and corporate users to gather important information efficiently In order to increase sales marketing documents product data sheets and white papers should be distributed to the partners in an efficient manner Sales leads can be shared amo
237. rs goes down the portal server automatically fails over to another available portlet server that is running the same portlet When the portlet server comes back on line the portal server automatically starts to use it again Nevertheless several of the commercial application servers provide high availability system As an elucidating example the Oracle 91 Application Server has multiple features with the specific goal of keeping the system up running and available The system is designed with a no single point of failure strategy and connections are automatically rerouted around failed elements of the setup Transparent application failover keeps the users of the system unaware of failing server instances while the automatic death detection combined with the fast restart architecture takes care of getting failing instances of the system quickly up and running again if a failure should occur Oracle A 11 3 Maintainability Analysability The BEA system contains a feature where each JSP and servlet invocation counted and timed The administrator can easily check 1f some part of the portal suddenly is using much more time than usual indicating some failing connection or similar problems The Apache system has no clear distinction of what is the framework and what is the API making analysis and bug hunting a more problematic process On the other hand IBM s Portlet API is very clean and makes a clear distinction between the portal
238. rsion of a new portal use test groups When the portal satisfies the set needs import the definitions to the production server Direct File Handling BEA have a direct link between one portal and one web application By copying the entire directory in which the web application stock portal resides to a new directory in the same J2EE enterprise application a new portal 1s created This 1s judging from the documentation the proper way to create a new portal In this new empty portal one can begin to define pages and portlets that should be included This 1s done using the stand alone graphical user interface called E Business Control Centre EBCC which directly edits the XML files used by the J2EE server system BEA points out that there 1s nothing hindering the administrator from doing these changes by hand however it 1s considerably easier to use the graphical interface The portal 1s first defined and entered into the enterprise application s definition files Next elements like skins layouts portlets and user profiles are added to the portal s web application definition files The workbenches are created and defaults for new users are defined The portal s definition files are then synchronized with the J2EE server After this further administration 1s done through the portal server s administration consoles which are elaborated on in a Chapter 9 3 Administration and Delegation 10 4 Portlet Creation Not only the
239. rtal Click the icons M to launch the administration tools To See the i a Personalization get more help as you work with the tools click to view Advisor for tags and online help or the book icon to view the developer s quide ipo io help Pee a sample application User Management Catalog Management Administer users and groups and Create and administer catalog content their associated properties more and structure more explanation explanation Order Management B Payment Management View and manage product orders View and administer order payments more explanation more explanation Portal Management Create and administer portals and portlets more explanation Local intranet Figure 20 The WebLogic Portal Server Administration Tools The system administrators are the only ones that may make new users and groups They may also deploy new portals A system administrator may create new portal administrators and group administrators He may further choose which tasks these new administrators can do and whether they are allowed to further delegate these tasks A portal administrator may administer the properties and make new administrators for the portals which he have access to but only if he have gotten the necessary rights from the administrator that created him Users must belong to a special group called AdminEligible to be granted any administrator privileges The WebLogic Portal Management start page
240. rtal makes good sense In these reduced usage scenarios some of the functionality could be altered and tailored to the specific needs of the organization For example some fields of the form could be left out some could be pre filled with the most used or default data and others fields could have menus or other selection facilities attached With carefully designed interfaces simple and intuitive enough to be used by anyone the corporation can avoid the costs of training the users of the systems Plumtree G If the parts of the enterprise application that employees use more often were made more accessible and simpler to use the time spent on these parts could be reduced considerably Since these parts are used considerably more often than the other parts or constitute the only parts used by many employees the total time the corporation spends on this application as a whole will also be decreased considerably This will free more time to do valuable work Another effect of making the application easier to use 1s that the application may also be used more often considering that the barriers for using it have been lowered This can be advantageous in many cases the amount of data cannot ever be too much An obvious example is the situation where the portal is used in an extranet scenario where customers can place orders directly into the corporation s order processing application Another effect 1s that the data entered may be of a better qua
241. rtals a Literature Review advanced PDAs have full blown web browsers enabling the PDA to directly access the portal in the same manner as one would at a stationary computer To facilitate the usage of the portal from the reduced screen sizes which the PDA offer it would be appropriate to make a special theme or skin tailored for the PDAs screen sizes 5 3 5 Workflow and Business Process Automation Many operations in an organization require several steps for completion Let us take an example of hiring a new employee This new employee will need a new user in the computer systems an order for a parking lot space must be fulfilled a new employee access card must be made the wages and benefits system must be updated and several operations like these must be fulfilled All of them must be properly done and some of them cannot be done until some other task already are finished making a dependency tree of task Several of the tasks are done by different people in different parts of the organization This flow of operations is commonly called a workflow This whole operation may be made more efficient 1f the workflow 1s supported by some system This 1s business process automation The manager could start the process by initiating the predefined operation new employee The portal then presents a form in which the manager must type the personal information of the employee The system will have several required fields and not let the mana
242. running the portlet This contrasts to how Plumtree have solved this problem as they have a mechanism of sending the customization data back to the portal server for storage 7 5 4 Software Quality Model References Adaptability Oracle boasts that their portal is internationalized However the only element mentioned is the language selection and again the dates times currencies and numbers are not mentioned The locale is based upon the browser setting Conformance The Oracle portal system requires both the Oracle application server and the Oracle database This makes it one of the most vendor locking portal systems around However the Oracle 91 application server conforms to the J2EE standards thus being able to run components conforming to these standards Scalability The Oracle 91 Application Server is scalable and can run on multiple physical servers The portal system inherits this feature and it 1s thus possible to handle very many concurrent users 7 6 Plumtree Plumtree Corporate Portal Plumtree prides themselves of being the founder and leader of the corporate portal market Incepted in 1997 the company definitely was one of the first to enter the market They claim to have been cash flow positive since 2001 and grown revenues consistently since their inception They are a dedicated corporate portal business Plumtree G The company states Unlike almost any other type of software corporate portal softwar
243. rvice lets the developer insert string values on string keys and then invoke a method to persist the new values Configuration is done using the Registry which is a set of XML files Again the clean stand alone API from IBM provides the most tidy and centralized way of handling state The PortletSession provides for the temporary state handling and 1s scoped per portlet per workbench per user The PortletData provide persistent state and 1s scoped similarly to the PortletSession unless the portlet resides on a group page workbench in which case it is scoped per portlet per group workbench PortletSettings provides for the configuration details These are scoped for all portlets with the same id A set of settings are always provided with the portlets however the administrator may instantiate new portlets giving them a new set of settings 10 8 Roles and Permissions Roles and permissions are explained in Chapter 10 2 Security These properties which the user either explicitly is given or implicitly are granted by group membership can be tested for by way of method invocations on some object The 114 Modular Development Frameworks for Corporate Portals a Literature Review only system that directly mentions this way of access control is Apache Jetspeed which provides the system as a services This system can be queried of whether a user is in a specific role and whether he has a specific permission 10 9Intern
244. s of the Plumtree portal system Reviewed in the previous section these will not be discussed further Enterprise Class Gadget Suites An enterprise class gadget suite is a suite of portlets made for a specific enterprise application Several enterprise applications are installed without much customization For such systems a gadget suite is made featuring a set of predefined gadget web services simplifying and accelerating deployment In Plumtree B Plumtree states This year Plumtree is releasing Enterprise Class Gadget Suites for applications such as Microsoft Exchange Documentum Lotus Notes and Cognos e Applications Enterprise Class Gadget Frameworks A gadget framework is a separate framework made for a specific enterprise application Instead of having a static set of predefined portlets a gadget framework exposes application objects and functions from the underlying enterprise application With help from a graphical wizard developers may assemble their own gadget web services in an efficient manner The developer picks the objects he wishes to make a gadget web service from and applies a set of framework functions to these objects to make them portal ready The developer may transform raw data sets to be presented in as portlets Forms querying the user for arguments may be created The frameworks enables the developer to make forms to capture user and administrator preferences and have functionality to store and retri
245. s that are saved between each user session This means that if the user logs out and then logs in the persistent variables in the state will be restored This 1s often used to store a user s preferences and configuration concerning each portlet The user s global preferences are also a part of the user s persistent state for example which workbenches the user have defined what portlets are on each workbench and the theme selected The scope of state variables can be different A user might have a specific portlet present on several workbenches and one issue is whether the state should be one for each instance or one for all instances In addition the concept of user groups 1s another place where scope is an issue a portlet s state could be common for all 113 Modular Development Frameworks for Corporate Portals a Literature Review members of the group or each user could have their own state associated with the portlet In addition when administrators install new portlets they often have to supply some configuration details for example the hostname of the underlying enterprise application system to which the portlet should connect This can also be viewed as a type of persistent state variables however these are global and persistent The different frameworks have solved these issues in different ways some of which will be highlighted Two tier rendering systems The two tier systems are in a special situation when i
246. s the first time a user requests the resource and when the JSP file is modified at all other times the cached class file is invoked directly This makes for fast code as the files are not parsed on each request as in the case of for example Microsoft s ASP and Apache s PHP type of code The already compiled code is merely invoked by a method call The objections against JSP are abundant e g Stevens 2002 and Hunter 2000a 2000b The complicated three stage cycle of invocation makes for three entirely different error sources The transform from JSP to Java Servlet source code must obey 74 This is a truth with some modifications Firstly Java is originally also an interpreted language where bytecodes are executed on a Java Virtual Machine although this process has been supplemented by intricate just in time compilers that further compile the bytecode down to native machine code Secondly Apache PHP for example also have the possibility of being compiled to an intermediate representation thereby accelerating the execution of code made in this language dtes Modular Development Frameworks for Corporate Portals a Literature Review the JSP conventions and may fail Then the resulting file may have syntactic Java errors making the compilation fail Then finally the code must run and produce HTML This output may of course contain HTML errors This complicated dual rewriting process produces HTML that may be quite bizarre in con
247. sarily requiring the Turbine framework It would also have made portlets portable enabling them to run on any server implementing the standard portlet API This new API will be further discussed in the IBM section of the analysis In the current API the interface Portlet must be implemented by all code that should run within the portlet environment There are several sub interfaces and abstract classes that goes with this base of special interest are Portlet PortletControl PortletController and PortletSet These relate to each other as shown in Figure 12 Turbine Screen PortletController PortletSet Portlet Portlet Portlet Portlet Figure 12 Conceptual relationship between Portlet PortletControl PortletSet and PortletController rendered within a Turbine Screen The PortletSet is contained within a PortletController The PortletSet contains all the portlets that should be rendered The PortletController may be paned meaning that it can contain several sets of portlets selectable via tabs The PortletControl is The Portlet API JavaDocs for Jetspeed version 1 3 is available at http www bluesunrise com jetspeed docs javadocs Accessed May 5 2002 44 Modular Development Frameworks for Corporate Portals a Literature Review responsible for displaying the window that the portlet s content reside in Finally the Portlet is executed and its content is included in the output It is worth t
248. se Sept 24 2001 Web site http java sun com 2ee connector Accessed May 25 2002 Java Specification Request 155 JSR 155 JSR 155 Web Services Security Assertions JCP Initiated Oct 29 2001 http www jcp org jsr detail 155 jsp Accessed June 4 2002 Java Specification Request 162 JSR 162 JSR 162 Portlet API JCP Review ballot Jan 22 2002 withdrawn Jan 20 2002 http jcp org jsr detail 162 jsp Accessed June 4 2002 Java Specification Request 167 JSR 167 JSR 167 Java Portlet Specification JCP Review ballot Jan 28 2002 withdrawn Jan 20 2002 http jcp org jsr detail 167 jsp Accessed June 4 2002 Java Specification Request 168 JSR 168 JSR 168 Portlet Specification JCP Initiated Feb 11 2002 http jcp org jsr detail 168 jsp Accessed April 22 2002 Owendo 2002 The Lowdown on Enterprise Information Portals EIP http www owendo com technocorner resources rd rd 1 html Accessed Jan 25 2002 PortalsCommunity 2002 PortalsCommunity com Fundamentals author Unitas Corporation http www PortalsCommunity com library fundamentals cfm Accessed Feb 28 2002 Security Assertion Markup Language SAML XML Based Security Services TC SSTC Security Assertion Markup Language Oasis http www oasis open org committees security Accessed June 4 2002 standard ISO IEC 9126 1 Information Technology Software quality characteristics and metrics Committee Draft dated Jan 2
249. se application This includes a large set of enterprise java beans and three web applications Of these the stockportal web application 1s a default portal including everything needed to make a portal This layout is shown in Figure 17 52 Modular Development Frameworks for Corporate Portals a Literature Review System Database Read only Filesystem Configuration and Code Source Controlled e g CVS Configuration lt files Synchronize E Business Control Center EBCC Figure 17 Relationships between the different entities in BEA s portal system The documentation BEA C states that to make a new portal a copy of the stock portal directory is made and placed in new directory on the same level The name of the directory is the name that the portal web application gets The WebLogic server is made aware of the new portal web application within the portal enterprise application by configuring it using the E Business Control Center This is shown in Figure 18 One server installation may thus be used to deploy multiple portals File Tools Window Help 8a 4 Opened myportal MyPortal Explorer Presentation 777777777777 VS E Editor Portal MyPortal alax Application portal Description optional Name Filter partial names allowed ooo ew Vertical Navigation Bar URL optional Portals Ess myportal MyPortal stockportal StockPortal Enti
250. seen First while most Java based portal systems require the entire J2EE platform to run at least one other only requires a servlet container to run Next some systems use the user authentication system already defined in the J2EE standards while others have chosen to use application level authentication Lastly the degree to which Servlets and JSPs are employed in the portal architecture varies greatly J2EE vs Servlets BEA Portal requires the BEA J2EE application server The system uses several web applications in addition to multiple Java Enterprise Beans to run their portal solution thus requiring the full J2EE specification IBM just changed their portal server s API to require that each portlet also were a servlet This means that each portlet application 1s defined as one web application which again implies that a full portal solution would require communication between multiple web applications several of the developers on the mailing lists of open source projects feel that the full J2EE architecture with its enterprise applications 1s bloated and requires too much overhead Turbine and Jetspeed does not require this but runs on the Servlet Container alone The IBM portal that just got discontinued in favor for the new version 4 1 also ran on the servlet container alone User Management BEA seems very dedicated to the J2EE environment and uses the architecture s user authentication procedures This seems to be the o
251. sider other users schedules while planning and coordinating their work One can superimpose several users schedules on top of each other thus making it possible to find available holes in their combined schedule or at least find spots where only a few of the people have something booked already similarly one has the possibility to book meetings with a group of colleagues as attendees submitting the meeting for approval directly to each of the members of the group When all attendees have accepted the meeting it is automatically added to their calendars possibly notifying everybody of the schedule entry A supervisor is often able to overrule a subordinate s calendar and may add or remove events and tasks in it without their approval and merely let the system notify them of the newly entered event Resource Allocation A group calendar application 1s often accompanied by a resource booking facility A user that wants to arrange a meeting needs to allocate time from each of the attendees similarly the user would also need to allocate a projector and a meeting room Alternatively an employee might need to borrow a company car for an off site meeting Such entities can be booked through such a resource booking system Brian Detlor 2000 argues for the notion of a shared information work space which can be formed within a portal system This work space will in Detlor s view facilitate the creation exchange retention and r
252. ss Restriction The PDK have facilities to enable the developer to restrict access to the portlet in several ways It can control whether a user should be able to see the portlet at all In addition the portlet can decide whether to enable or disable certain functionality based on the user Authentication Level This latter feature seems a little crude the return value of the authentication level getter is simply an integer User abstraction object A User object gives access to the user using the portal This might be a PUBLIC user denoting that the user at the other end has not logged on yet If the user has logged on the user object enables the developer to get parameters of the user including username the Subscriber object and a Location object for the user The subscriber 1s usually a company confer the subsection on hosting and ASP environments The location includes the address of the individual and his company and strangely enough a getter for the user s X and Y position EC m Modular Development Frameworks for Corporate Portals a Literature Review Preferences User preferences are stored locally on the server running the portlet using either a DBPreferenceStore or a FilePreferenceStore An obvious problem here is the question of what happens when the user is deleted from the portal There does not seem to be any automatic deletion of preferences and personalization data from the database or file system on the server
253. t Kits PDKs These PDKs hides this complexity behind a set of APIs Oracle has made a PDK for Java development and one for PL SQL In addition the May 2002 release of the PDK contains beta versions of a PDK for URL based portlets and a PDK for Web Services based portlets This remote approach is very similar to the main idea of the Plumtree portal system which is analyzed in the next subchapter The general layout of this remote approach is described in more detail there The PL SQL Provider must be installed on an Oracle91 Application Server not necessarily the same as the portal server Using this type of provider long time customers of Oracle may leverage their existing knowledge of the database procedural _ 78 Modular Development Frameworks for Corporate Portals a Literature Review language PL SQL to develop portlets This approach features direct access to the database on which the PL SQL Provider 1s running The providers are registered using the administrative interface in the portal When doing so the portal connects to the provider and queries which portlets it has available When the provider replies the portal incorporates the portlets into its registry making them available to be placed on portal pages Per default only the user that added the provider have access to the portlets so he must alter the access control list for the portlets manually to some more lenient restrictions 7 5 2 Framework concepts In
254. t comes to state handling The problem is that the portlets are residing on separate physical servers and the question of how to handle each user s state variables especially the persistent ones arises Oracle have chosen to let the portlet server handle this and the user thus gets one session on the portal server and one session for each portlet it is using If the portlet makes use of persistent state this 1s stored locally on the portlet server using either a FilePreferenceStore or a DBPreferenceStore object The obvious problem here is the one of user management and what happens when a user is deleted since there is no central place where the user s profile is stored Epicentric have solved this elegantly by making the portal server handle all the persistent state The portlets on the portlet servers can send back attributes that should be stored via the HTTP headers Next time the portal server invokes the particular portlet for the particular user these parameters are sent along The portal server thus acts as a central persistence store and the user management problem is eliminated Single tier rendering systems Apache Jetspeed uses a XML file with Portal Structure Markup Language PSML to store the preferences for each user Apache Jetspeed seems to have no clear way of organizing temporary state However persistent state is provided by a persistence service providing one parameter store per portlet per workbench per user This se
255. t for graphics user interfaces client side Given more time such a language and environment will probably come into existence as several platform spanning languages already exist This will clear the way for non browser based portals Such a portal can be envisioned as some sort of 6t C and Common Language Infrastructure ECMA standardization http msdn microsoft com net ecma 5 The Shared Source CLI which builds on both Windows and FreeBSD is available at http msdn microsoft com net sscli The Mono Project s website http go mono com 7 Web Services Interoperability Organization s website http www ws i org 65 PHP Nuke s website http phpnuke org postnuke s website http postnuke com 7 Slashdot News for nerds stuff that matters http slashdot org Slash http slashcode com 133 Modular Development Frameworks for Corporate Portals a Literature Review standardized virtual operating system in which smaller or larger stand alone applications are installed exactly in the same way as have been described with java based portals using a web browser as user interface The virtual operating system could handle user authentication roles and permission domain wide common data storage and security The user interface of such a system could look and be operated much more like a proper operating system with variable sized windows that could overlap The controls could be more elaborate with
256. tain a large set of different entitlements each with its own conditions A user 1s often assigned multiple entitlements An entitlement 1s created with the entitlement editor An administrator may tick off the different types of conditions available and more closely specify when the condition applies Every portlet in the system can now ask whether the active user has the different entitlements This forms a powerful tool by which to tailor the appearance of the portal s pages to each individual user As a simple example the system may show a user who is entitled ExperiencedJavaDeveloper a new article about some advanced Java topic and users entitled HumanResourcesEastCoast must fill out survey about their subjective impression about employee satisfaction If a human resources person from the east coast happens to be an experienced java developer he or she will both see the article and the survey 9 2 Security 9 2 1 Access Control Most portals solve the access control problems by using a set of elements namely users and groups and permissions and roles As these concepts are elaborated on in Chapter 6 Basic Portal Functionality they will not be reiterated here ACLs are particularly used in the Oracle portal to delegate administration and to control the user s access to different portlets and other features 9 2 2 Single Sign on The Single Sign on concept is also elaborated on in Chapter 6 Basic Portal Funct
257. tal systems that merely supply a predefined non extendable set of portlets from which the user might choose a setup are considered not to have any framework e Functional components refer to the application like functions of a portal system that often would be present in a lower layer of the architecture of the system The functional components will often be used by several application developed on the portal like some embedded service For example an application could be a group calendar while a functional component could be the user notification system used by the calendar application when a deadline 1s approaching e Java 2 Enterprise Edition J2EE is a Java application server standard developed by Sun Microsystems Inc in collaboration with several leading software vendors Appendix B contains a review of this standard Several of the frameworks analyzed builds upon this standard Modular Development Frameworks for Corporate Portals a Literature Review e Modular development framework refers to a development framework that enables the programmer or designer to develop applications and functional components in a modular way Each module may be designed and programmed individually The full system is assembled using these newly built modules along with standard modules that come with the framework e Module also called Portlet Application refers to a set of portlets which often forms a functional unit A module might be anything fr
258. te http www plumtree com webforms MoreInfoFormTemplate asp formkey 14 However registration 1s required to gain access In addition the Plumtree demo portal at http portal plumtree com contains all documentation Plumtree A The Corporate Portal Market in 2002 Feb 18 2002 file Corporate Portal Survey White Paper February2002 pdf Plumtree B Enterprise Class Gadget Web Services and Frameworks no date file Framework Whitepaper pdf Plumtree C The Plumtree Corporate Portal Technical White Paper no date file Plumtree 4 5TechnicalWP pdf Plumtree D The Internet Architecture of a Corporate Portal no date file Internet Architecture Whitepaper pdf Plumtree E Plumtree Gadget Web Services Web Enable Your Entire Business no date Plumtree F Plumtree Technology and Channel Partners no date Plumtree G The Plumtree Difference no date 149
259. tegrated into the portal This search engine supports different search characteristics including Boolean proximity fuzzy linguistic stemming and advanced metadata The search only includes documents that the user is allowed to see in the first place thereby preventing that any access constraints are breached 7 6 2 Framework concepts and features The Plumtree s special two stage rendering approach makes it difficult to talk of a single set of framework features Plumtree portlets can be programmed in any HTTP R6 Modular Development Frameworks for Corporate Portals a Literature Review aware language thus including any programming language whose platform also includes a web server capable of CGI scripting This is in addition to programming environments made especially for the web which includes HTTP aware constructs natively for example ASP JSP Java Servlets and PHP Nevertheless Plumtree have developed gadget development frameworks for some popular programming environments Plumtree C These code libraries features functions that act as an API for accessing and setting preferences and administrative information that the Plumtree portal server has communicated to the gadget using HTTP headers and cookies This relieves the programmer from the burdensome task of parsing these special HTTP headers and cookies enabling him to focus on the programming of the gadget application logic Gadget Web Services are the portlet
260. ternationalization Multiple Languages All text appearing in the portal including wizards dialog boxes and help files are translated to 27 different languages The language selection 1s based on the user s browser settings The self service publishing facilities within the portal also enables users to publish their content in multiple translations Authentication The portal uses the application server s Single Sign On SSO architecture for authentication Using this system a user may log on to any part of any system developed on the application server and gains access to any resource protected by the SSO system The SSO is fully integrated with Oracle s Internet Directory OID but can also integrate towards third party vendors security management systems Netegrity s SiteMinder is mentioned as an example Users and groups The Portal uses Oracle Internet Directory as its repository for user and group definitions The user and group structure may be administered through the built in administration interface embedded in the portal or using the administration tools and APIs delivered with the OID system Access Control Lists and Administration Delegation An access control list ACL system 1s employed throughout the portal server Access control lists protect portal objects including pages styles items and portlets Privileges for accessing customizing or modifying the different objects are granted to specific users and g
261. terprise network It could potentially download and execute code read or destroy files and other resources make unhindered connections to any server on the enterprise local network and even make use of locally exploitable security weaknesses of the hosting operating system all while giving reports back to an outside host 12 1 5 Consequences A standardization of a portlet API and web services portlets would lead to many new possibilities and opportunities All companies that install a standardized portal system would instantly be potential users of both locally installed and remotely served portlets Some likely effects will be discussed briefly Stand alone Portal Applications The portlet API standardization would make it interesting for several parties to make small and large portlet applications Plumtree states in their February 2002 customer survey Plumtree A that Nearly half of survey respondents have developed ten or more graphical web services for their portal deployment and 12 have developed 50 or more This included both enterprise integration applications and stand alone portlets however most were in the latter category Several software companies will use the opportunity to make stand alone portlet applications that does not depend on any underlying application Such applications include all types of database near front office and productivity tools for example group calendars project management systems collaboration t
262. that a deadline 1s approaching A notification 1s sent when some event happens for example if the user receives an email or some new task appears in the user s workflow queue Both concepts require the user to be notified in some manner The alerts and notification system can be built into the portal system or available as a service to the portlets Several ways of notifying the user can be available to the portlet each used in different settings or attached to different notification levels There might be an alert portlet showing the different alerts and notifications that have occurred Then there might be a mechanism of sending an email to the user so that he 28 Modular Development Frameworks for Corporate Portals a Literature Review will see the notification in his email inbox As an even more urgent notification paging the user or sending a text message to his or her mobile telephone can be possible 5 3 Push Information and Subscriptions Several articles including the original analysis from Shilakes and Tylman 1998 mention the possibility to push information to the user instead of requiring the user to pull it off the system This is similar to the concept of notification where certain events are programmed or configured to send out a notification to the user This is also called subscriptions since the user is subscribing to certain types of information When a new sales document is added to the sa
263. that can be shared and exported between portal sites and portal server deployments They can be used when constructed a new site Shared components include modules pages themes and other user interface elements e Rapid Site Assembly As anew portal site is created the administrator may pick from reusable shared components and can assemble the site using the site assembly graphical user interface e WYSIWYG creation of menus and submenus Epicentric provides a WYSIWYG creation of the menus used by the users to navigate through the portal e Export and Import of Portal Definition Backup and Staging In addition to visually and with a graphical user interface create and manage the portal Epicentric provides a feature for the export of an entire site definition Not only the definition of the portal but also the portals components can be exported and imported The definitions are exported as XML files These files can be imported into the same server as it was exported from but can also be imported on another portal server These are very interesting features and can be used for several functions 108 Modular Development Frameworks for Corporate Portals a Literature Review Sharing Sharing of portals definitions between portal server installations Backup Take a snapshot of the portal definition for later crash recovery Versioning If a new setup proves worse than the old one go back Staging Go through alpha and beta ve
264. they are placed For example there is a concept of a capability map that maps which capabilities the connected browser have explained in the next subsection This functionality is implemented in Jetspeed and not in Turbine as one would expect based on the generality of the function The same goes for the different markup supports e g WML and HTML which also 1s implemented in Jetspeed 41 Modular Development Frameworks for Corporate Portals a Literature Review 7 1 2 Framework concepts Panes The workbenches in this framework are called panes The system allows the user to make new panes A pane uses a Controller to arrange the content The controllers are called Layouts when shown to the user Interestingly there are two types of layouts the first one can contain portlets while the second one may contain a new set of panes The configuration screen enables the user to add portlets onto a portlet layout and panes to the pane layouts There are two pane layouts available in the default configuration The first one is called Menu pane where the added panes goes into a list on the left side of the containing pane The other one is called Tab pane and gives a new horizontally tabbed pane set Within one pane one may choose to use yet another pane layout thus making a hierarchy of panes Figure 6 only displays one level of panes and this set of panes only contains one pane Home There are several portlet layouts w
265. ties using Permissions The site administrator may also elect to share the responsibility between multiple co administrators by restricting administrative rights within the portal site This is called Collaborative Site Management Each portal site is managed from its dedicated Site Console The console lets the site administrators manage all aspects for a portal including the workbenches portlets and styles All portal sites may also be monitored or managed centrally with the Server Console which 1s located within the Portal Command Center Content Management eXtended Content Management XCM is an integration layer for already existing document management systems Epicentric reasons that many corporations already have one or several document management systems in place already XCM integrates multiple systems by aggregating the content and presenting it to the user through the portal s user environment XCM is delivered as a suite of modules and core system services It provides a document repository and a system of connectors to other document management systems Epicentric provides XCM connectors to solutions like Documentum and Interwoven Epi B It can also access files from file systems XCM 1s described as a Content Management Middleware layer It provides methods for creating new or specialized display Modules Back end system connectors may be made to integrate to proprietary or legacy document systems XCM handles both content
266. tle over the heart of the enterprise IT stack as portals begins to be the focal point of any organization s IT strategy The push for a portlet standardization is in effect coming from the customers driven by the high costs of portal implementations However the vendors will not really be interested 1n an actual standardization Standards would commoditize their offerings and thus enable other companies to exploit their application logic and infrastructure functions giving them less leverage for their application servers and infrastructure products Epicentric gave an example of this usage however the web page in question is now removed from Epicentric s site Epicentric has lately moved away from the Modular Web Services name and the concept is now called Epicentric Web Services The example used was a financial services institution that developed a modular web service This financial institution s customer was using the Epicentric portal and could therefore import the financial institutions modular web service into their portal by instantiating and configuring a MWS Building Block 129 Modular Development Frameworks for Corporate Portals a Literature Review Margulius predicts that a likely outcome of these standardization efforts 1s that basic interfaces between portals and portlets are defined however the higher level interfaces for cooperation such as sessions or process flow management will still be proprietary
267. tlement Segments ae ade Content Selectors S Placeholders EER Portals F a Portlets Description Endre s Test Portal Presentation ii Test Portal Content LIRL iframeworkipage jsp Header URL optional frameworksheader jsp Footer LIRL optional framewvork footer jsp Portlets Available portlets Portal pages MyPortalPage iframeworkivnav bar jsp Horizontal Navigation Bar URL frameweorkhnav bar jsp Portal Vvebflowe Re EE Selected portlets WworldMews Defaults fed Figure 18 The new MyPortal portal web application with the configuration screen to the right Different resources are scoped within different sections of the J2EE hierarchy confer Appendix B Portal web applications are scoped within an enterprise application Group portals are logical divisions of portal pages thus scoped within a portal web application This is shown in Figure 19 3 Modular Development Frameworks for Corporate Portals a Literature Review Applicaction Portal A P Group Portal TENE 2 Group Portal E B 2 xdi Figure 19 Scope of Group Portals vs Portal Web Application vs Enterprise Application Webflows portlets skins and layouts may be shared between the different group portals They cannot be shared between different web portals except by copying the physical files consisting the resource from one web portal
268. tlet crashes midway through its rendering the resulting page can be incomprehensible for the user s browser This 1s especially problematic if the problem does not clear by itself The portlet will continually crash some way into the rendering and since the resulting workbench is incomprehensible the user cannot remove the portlet from the workbench either Apache Plumtree and Oracle use a system where the portlet is supposed to return its entire content in one operation Apache is doing this using a method invocation on the portlet object which is required to return the entire portlet content Plumtree and Oracle are using the two tier rendering approach thus insulating the portlets rendering from the rendering of the rest of the workbench It is possible to make a portal server that could embed potentially error prone portlets in a protection shielding This could be used on portlets that are 1n an early stage of development beta versions and new untested portlets Instead of letting the portlet write directly to the output stream the portlet output could be temporarily stored before inclusion into the workbench s markup This is in effect what happens with the Jetspeed s getContent and the two tier rendering approaches If the portlet crashes an error message can be shown instead of the possibly incomplete content from the portlet It is even achievable to validate the portlet s outputted markup for completeness and correct
269. tlets may also be changed based on entitlements this 1s gone into further detail in the Framework features subsection 7 2 3 Framework features JSP Tag Libraries Internationalization The programming of portlets is done using multiple JSP files per portlet The JSP files may contain JSP tags accessed by importing tag libraries into the JSP file Confer Appendix B The WebLogic portal includes a set of tag libraries to enable the integration of the portal framework s features with the portlet logic WebLogic supplies dozens of tag libraries to make the development of JSPs easier For example there are tags to refer to the user s session to the request and the response objects and similar JSP and Servlets related objects There are several libraries to query the personalization system mentioned in the last subsection including content management ad placeholders and user management These tags may change the content in a portlet based on the different properties of the user and which entitlements that are in effect Tracking libraries enable the developer to monitor user behavior and user events like clicking on a product or content There are also tags that enable the developer to efficiently manage a product catalog this goes in under the commerce services mentioned in the beginning Two simple tags involves internationalization lt il8n localize gt tag used to define the language country variant and base bundle name to be used t
270. to make a currency conversion and is programmed to use a web service Web Services Architecture Requirements http www w3 org TR wsa reqs XML 1 0 W3C Recommendation http www w3 org TR REC xml 58 Web Services Activity http www w3 org 2002 ws 25e Modular Development Frameworks for Corporate Portals a Literature Review 2 The client locates the URL to the web service using some means assume hard coded location 3 The client knows the method names and arguments that the web service takes called the web service s interface using some means Assume hard coded interface description 4 The client translates the parameters needed for the conversion request to the format required by SOAP 5 The client constructs a SOAP request specifying the method name on the remote server in addition to all the necessary parameters 6 A HTTP Connection is established with the remote machine using the Web service URL and the SOAP request is transferred 7 The web services implementation on the server side translates the arguments in the request to the native language used in the web service 8 The server invokes the method specified in the request supplying the translated arguments 9 The method returns the return values 10 The return values are converted back to the SOAP specific types 11 The server constructs a web service response 12 The response is communicated back to the client using the still open HTTP connecti
271. to store user authentication and customization data The package ships with Hypersonic SQL a Java based RDBMS This enables a quick test installation Turbine Turbine is a framework for developing Java based web applications It 1s filled with features and services specially designed to make the development of web applications easier Turbine may be used as a complete Servlets based development framework by using the Turbine Servlet as the main controller However a developer may choose to use only some of Turbine s set of features and services thus utilizing Turbine as a repository of useful code Jetspeed is built on top of the Turbine Servlet 20 The database HSQLDB including Hypersonic SQL http sourceforge net projects hsqldb 39 Modular Development Frameworks for Corporate Portals a Literature Review Turbine takes care of the authentication of the user It defaults to use application level authentication thereby circumventing the servlet container s authentication procedures The documentation argues that the problem with container managed security is that it cannot easily be managed from within the application However Turbine does also support container managed security The system consists of an overall model that includes Actions Layouts Navigators Screens and Pages This is pictured in Figure 8 Figure 8 The entities in the Turbine Specification from Turbine s website Actions are user br
272. transport layer that 1s the connection between the user s browser and the web server 1s usually protected by the industry standard Secure Sockets Layer SSL Plumtree argues that the two tier rendering approach heightens security by providing an extra layer between the user and the enterprise application The portal server is accessing the portlet server which again 1s accessing the enterprise application The system can be set up so as there are no direct route between the portal server and the enterprise application thereby lessening the impact of a security violation or break in on the portal server By providing or interfacing to a single sign on system a portal server can heighten the security since users do not have to remember and possibly write down multiple passwords However this idea can backfire if this single portal password 1s disclosed exposing a whole set of underlying enterprise applications 11 2 Reliability Fault Tolerance A portal is a complex system integrating towards multiple underlying sources that can crash and create problems independently In addition each portlet is a part of a full web page which makes the system sensitive to each portlet s markup language output Finally the portal server itself could crash BEA and IBM s system is using a system of recursive and sequential portlet content inclusion If a portlet outputs any bad markup language either because of a logical bug or because the por
273. trast to the original JSP file making it problematic to find where in the JSP file the error was made In addition the error codes from this process is inherently difficult to decipher especially the middle compilation step as the coder can t control how the Java source code is generated In addition JSP is supposed to divide the Controller and the View in the Model View Controller paradigm of coding The problem is that all such code within HTML systems make it very hard to divide completely the code logic and the html relying on the coder to be very stringent with his coding patterns An in addition the tag libraries and the tag invocations spread throughout the code will eventually make the resulting code look quite far from HTML An alternative to JSP is template based systems These systems have become quite popular and have been characterized by several authors Stevens 2002 DiBartolo 2001 Hunter 2000a 2000b and Messerschmidt 2001 as enforcing the MVC paradigm more rigorously than JSP e Enterprise Java Beans EJBs are distributable sharable code components These pieces of code logic are living within Java 2 Enterprise Edition servers in the EJB Container They are invoked from for example a web application by means of a Remote Procedure Call protocol called RMI IIOP The may also be invoked by other systems for example as a part of a graphical user interface application The enterprise java beans are of differe
274. tration tasks Alternatively the system administrator can decide that it 1s best 1f he controls the entire delegation having full control He would then take away the delegate right from the portal and group administrators All administration of the BEA portal except the creation of a new portal web application 1s done using the Portal Administration Tools This menu like interface gives access to user and group management facilities as well as portal management facilities Epicentric also have the notion of multiple portals within a server and the server administrator can grant administration rights to the portals owner or owners However he may restrict the administrative capabilities using permissions By giving subsets of portal administration rights to several people collaborative site management is achieved All administration of the Epicentric portal is done using the Site Console With this console the administrator may manage all aspects of the portal including the workbenches portlets and styles A central Server Console gives access to all portal sites This 1s located within the Portal Command Center An interesting detail of Epicentric s taxonomy is that all parts of 1t are protected by permissions Thus the administrator may delegate the population and structure of each part of the taxonomy to different persons within the corporation Oracle s portal system is protected throughout by its ACL system This includes pages wo
275. ttributes and entitlements control the visibility and availability of portal pages and portlets However where attributes only chooses whether a portal page or portlet is visible available or mandatory within one group portal the entitlements give much finer control File Tools Window Help So 48 Opened ExperiencedJavaDeveloper Explorer Presentation tree x Description optional penis if the visitor is an experienced Java developer Characteristics When all ofthese conditions apply Create Edit the visitor has all ofthe following characteristics Application portal Name Filter partial names allo e 4 w Entitlement Segments Developer a E ge ExperiencedJavaDeveloper Developer is equal to true SkillLevel is equal to High PreferredLanguage is equal to Java Entitle the visitor as a ExperiencedJavaDeveloper Description Determine if the visitor is an experienced Java developer LE Site Infrastructure EC Business Logic fal Presentation 5 Entitlement Segment Developer 3 Entitlement Segment ExperiencedJavaDeveloper Figure 23 Viewing entitlements within the EBCC Entitlements are based on the user s profile date time properties of the user s session and HTTP request The EBCC view in Figure 23 shows the entitlement ExperiencedJavaDeveloper and which conditions which must be met to be entitled with this
276. ture framework concepts and framework features and a section for references to the software quality model Chapter 8 9 10 and 11 summarizes and discusses the findings from the preceding chapter It is worth to notice that some elements are mentioned in more than one chapter as they are referred to in different contexts Chapter 12 tries to deduce some probable paths of evolvement of these systems based on current trends in the software market in general and the portal market in particular E E Modular Development Frameworks for Corporate Portals a Literature Review 7 The Vendors 7 1 Apache Software Foundation Jakarta Jetspeed Apache Software Foundation ASF 1s a non profit corporation formed to help the development of open source software The ASF shall provide a foundation for open collaborative software development projects by providing hardware communications and infrastructure The ASF is a legal entity so that companies and individuals can donate resources while be assured that those resources will be used for the public benefit It shall protect individual developers from legal suits directed at the Foundation s projects and protect the Apache brand The ASF was formed out of The Apache Group which was a group of individuals that initially formed in 1995 to develop the Apache web server The ASF currently hosts several projects Each project s members consist of a loosely knitted group of software developers
277. uctivity on their daily activities Consequently many modern enterprises lack a global view of their own data and information The problem results from the fact that the employees need to have a prior knowledge of both the existence and usage of the different resources both internal and external This might not always be the case either because the resource might simply not be known to the employee or the employee does not know where to look for it Schroeder 1999 In addition the user often needs some access privilege for the resource usually some username and password that have to be remembered All this makes for considerable obstacles the employee must first aware of the resource then request and gain access and finally remember yet another username and password These difficulties may eventually lead to some relevant information not being considered for the case an employee is working on in effect making the employee take an uninformed decision suboptimal or even wrong A portal system can make both internal and external information accessible by providing consistent intuitive user interfaces for each source and by aggregating multiple sources into single views Schroeder 1999 Searches can be done through multiple sources thereby avoiding that the user misses important information due to lack of knowledge of some source Making information resources readily accessible from within the portal itself will promote the usage of suc
278. uld get access to the newly installed application and 1f applicable which access the individual people should get This would be done using the portal s access control lists giving access to for example the standard beta testing group and using the permission control system including the different permissions into already defined roles or making new roles 12 3 Other Technologies The focus in this thesis have become Java and Web Services However there are other technologies out there too The new platform from Microsoft NET 1s a clear competitor to the Java platform In addition several other more or less important technologies exists 12 3 1 Microsoft NET A full discussion of Microsoft NET is outside of the scope of this thesis however an outline is elucidating The Microsoft NET platform is currently being touted heavily by Microsoft as the technology for the future The core platform resembles Java to a considerable degree Microsoft has developed a new language for the NET platform called C This language is amazingly similar to Java In addition all code is compiled down to an intermediate form called Microsoft Intermediate Language MSIL this step also resembling the byte code of Java To run a NET program the Common Language Runtime CLR is required This is a runtime environment much like the virtual machine of Java However Microsoft have made the CLR flexible so that multiple computer languages currently c
279. unts of processor time and input output activity to be produced The caching system is exposed as a Caching API giving the module developers the choice of how caching should be performed The developer may choose expiration times and behavior for cached objects The server has a concept of Passivation giving the developer a choice of where objects and content should be stored when not needed by any user By default this 1s to the server s back end database but the developer may choose to use a specified storage system or not use the passivation mechanism by just keeping the object in memory The objects may be cached by any combination of keys for example user ID module and or domain 65 Modular Development Frameworks for Corporate Portals a Literature Review 7 3 3 Software Quality Model References Adaptability Epicentric mentions both character sets dates times in addition to languages as localization possibilities Conformance The system can run on several vendors J2EE servers thus conforming to the J2EE standard Scalability The Epicentric system runs on several vendors J2EE servers of which several are scalable The Epicentric system inherits these features and is thus scalable 7 4 IBM WebSphere Portal International Business Machines IBM is a computer industry giant with a history going back to before 1900 The company was officially founded as the Computing Tabulating Recording Company C
280. up Administrator Preferences Parameterized with Parameterized with Parameterized with PortletConfig objects PortletSettings objects PortletData objects User Page Concrete Concrete Portlet Portlet Portlet Servlet Concrete Portlet Portlet roup Page Servlet Concrete a Portlet Portlet Portlet Figure 26 Relationship between the different levels of instantiation in the IBM Portlet API Finally when the user actually views the page a PortletSession object is created for each concrete portlet instance the user have on this particular page This object represents the parameterization of the User Portlet Instance and stores transient information regarding this single invocation of the portlet Portlet Applications As mentioned the portlets can be grouped into Portlet Applications A portal application will typically be a specific module for example a group calendar system or a project planning system The portlet application contains all resources needed to zl Modular Development Frameworks for Corporate Portals a Literature Review run the portlet application for example the images property files and active components like JSPs Java code and the portlets Please confer with Appendix B Web Application A portlet must be packaged within a portlet application In the same manner as with the portlet and concrete portlet relationship a concept of portlet application and Concrete Portlet Appl
281. upport the concept of multiple workbenches and all except BEA s system support the dynamic creation of new workbenches The users of a portal can most often create their own personal workbenches In addition most systems provide for some concept of group or community workbenches These are workbenches which the user either chooses to accept or are just given without any explicit accept from the user zb Modular Development Frameworks for Corporate Portals a Literature Review 9 7 Invitations One feature of the Plumtree portal worth mentioning is the concept of invitations The portal can generate special URLs that when followed will enroll a person to the portal s user database The portal generates a default user profile for the newly enrolled user This system is especially meant for B2B and B2C settings where for example viral marketing of the portal 1s desired An email can be sent out to all of the company s customers with such invitation links embedded 9 8 Remote Portlets Plumtree and Epicentric use a concept of remote portlets As the Plumtree system relies on the two tier rendering system in actuality all portlets are remote However they can be also be hosted on another company s installation and one portlet on a portlet server can thus support multiple customers Epicentric have started the Web Services User Interface WSUI initiative a SOAP XML approach to hosting portlets at remote sites This system in ad
282. ure 1 View from Plumtree Portal demo version available online The portlets are placed on a workbench by the means of some configuration scheme Some portals use selection boxes where the user ca see a textual representation of the portlets that appear in each of the columns that exists on the workbench and then a selection box from which to add portlets The user can then change the layout of the portlets by moving the already existing portlets between the columns or add or remove portlets to and from the columns A user interface for this style is shown in Figure 2 amp Personalize Page Layout Microsoft Internet Explorer g p File Edit View Favorites Tools Help QBak A z f L Search Favorites Media I LJ 3 al amp Address E http e my yahoo com config eval_layout amp src my amp partner amp page p 1 amp no_js amp done http 3a my yahoo com p E Go Welcome stolsvik Help Sian Out Content Layout Colors What s on your page Where the content goes Colorful themes and page management Select two or three column layout Move columns from left to right Change the order and location of content by selecting it and using the arrows Be sure to click Finished when you re done Personalize Layout for Endre s Frontpage Earnings Surprises Wine ofthe Day Healthy Meal Video Features Upgrades Downgrades Move Column gt 4 Move Column gt A Move Column Switch to
283. ust enable the users to direct responses to specific portlets 10 5 1 Portlet Output to User At some point in the processing the portlet must send its output to the user As all the analyzed portal vendors are using the same approach of rendering the full page for each action done by the user they all have to use some sequential output inclusion technique This is quite similar for all frameworks however some differences can be seen The Jetspeed approach is to invoke a method named getContent on each portlet The portlet should then return a string object representing the entire markup that this portlet would like to include The same approach is in effect used by the two tier rendering systems Oracle and Plumtree There is some overhead involved as all markup must be generated inside the portlet s code before it 1s returned to the portal server thus wasting temporary space However this system makes it possible to contain errors If the portlet crashes while processing the request the portlet will not have had the possibility to corrupt the output stream yet The portal server can choose to display an error screen instead of the portlet IBM and BEA are instead using a method where the portlet have direct access to the output stream As the portlet outputs characters to the stream the client 1s receiving The getContent method is actually supposed to return an ECS element but the net effect is the same Review the analysis o
284. w orders view order and payment history check payment statuses place service requests and support calls The corporation may track the customers site searches and portal navigation and thus try to pinpoint ways to improve the site By offering such selected internal information a corporation may gain several advantages The customers may become so happy with the organization that moving away from it 1s hard In addition by being proactive and develop new and customer focused features the company can gain a competitive head start This 1s often called the first mover advantage The corporation can also gain better marketing m Modular Development Frameworks for Corporate Portals a Literature Review prospecting sales field service customer relationship management service and support and thus get more sales Another advantage from direct customer interaction 1s that the corporation can get invaluable product feedback The products and the relationship with the customer may be improved in directions highly driven by the customer s needs Feedback forms questionnaires and support forms might be inserted in strategic locations making it easy for the user to inform the corporation of his experience with the products service and customer relationships including the portal Given a good and quick response from the corporation this will heighten the customer satisfaction and make it harder for them to leave the corporation Supplie
285. web application may be contained within one single jar file whose ending is war A web application is self contained and may not communicate easily with other web applications except by means of shared resources for example a RDBMS or the enterprise java beans scoped within the same enterprise application The JSPs and Servlets are active in that the server will not just merely serve their contents but will run the application code contained within them The server provides means for the code to access the HTTP headers that the browser supplies and means for the code to reply to the browser The Java ServerPages JSP architecture 1s rather complicated The system uses the code within html paradigm where Java code called Scriptlets are embedded within the ordinary HTML using a special markup syntax consisting of lt and gt There is also a notion of tags where HTML looking tags within the JSP files invoke pieces of Java code These tags are collected in tag libraries which the JSP developer imports into the JSP file by special import statements The tags code can later be invoked by inserting the tags and their arguments in the JSP file The web container s JSP interceptor first transforms the JSP file to a Java Servlet source code file This file 1s then further compiled to a Java class file using an ordinary java compiler The resulting executable Servlet is finally invoked and run This entire process only happen
286. web services The first most general are the Web Services Interactive Applications WSIA formerly known as Web Services Component Model WSCM This committee aims at developing a standard for interactive human facing Web services The second more portal specific are the Web Services for Remote Portals WSRP initiated in March 2002 This committee s purpose 1s expo Modular Development Frameworks for Corporate Portals a Literature Review Defining an XML and Web services standard that will allow the plug n play of visual user facing Web services with portals or other intermediary Web applications Interestingly IBM are apparently deeply involved with these standardization efforts as well as the standardization effort on the Java Portlet API confer the IBM analysis IBM are currently developing two different standards one called Web Services for Remote Portals IBM WSRP which is submitted to Oasis and another called Web services Experience Language IBM WSXL This latter one 1s apparently designed to be a superset of the WSRP standard Both the Oasis WSIA and WSRP are chaired by IBM persons WSRP 1s indeed chaired by Thomas Schaeck the same person that promoted the creation of a standard Java Portlet API on the Jetspeed mailing lists as described in the IBM analysis Chapter 7 4 1 Historical Review of the Portlet API In addition as mentioned in the analysis in Chapter 8 3 Epicentric Epicentric
287. y portlet standard to conform to yet e Technology Spanning Because of the loosely coupled system with HTTP communications the gadget web services may run along with the technology to which it integrates eliminating the need for bridges between the underlying Modular Development Frameworks for Corporate Portals a Literature Review technologies For example a Microsoft Exchange integration gadget may be programmed on the Microsoft platform using COM objects to communicate and then expose the resulting service using HTTP A Documentum integration gadget may be programmed in Java using Java APIs to communicate and again expose the resulting functionality using HTTP The HTTP communications acts as the single bridge defining a concise interface between the portal server and the portlets Wireless Device Server WDS The WDS enables users to access specialized versions of their Workbenches through mobile devices Supported devices include WAP phones synchronized Palm PDAs and RIM Blackberry pagers The server does not translate automatically between different markup languages Plumtree reasons that Plumtree C the sheer variety of handheld devices combined with the dynamic and interactive nature of the content access by Plumtree portals makes this an unworkable strategy Plumtree have instead focused on a platform where it easy to make gadgets useful in different settings Gadget developers can specify which device t
288. y requiring every employee to subscribe to the lists that correspond with their knowledge questions asked on the boards are channeled to the appropriate persons who then can decide whether they can be of assistance Organizational Learning Organizational learning refers to the process during which a company attempts to increase the corporate knowledge by increasing that of each employee as well as to establish good routines and practices in general Lessons learnt by mistakes must be recorded as repeating errors are very costly and should be avoided Brian Detlor 2000 argues that the communication space described in the next section facilitates organization learning The reason is that both information distribution and information interpretation are important elements of the organizational learning process When distributing information by making it easy for users to locate and consume information the corporation as a whole will learn and gain new insights When discussing and interpreting information originating in various sources common understanding is achieved and new knowledge obtained This new knowledge is fed back into the knowledge base and thus one more information cycle 1s completed NS Modular Development Frameworks for Corporate Portals a Literature Review 5 2 6 Collaboration Collaboration is according to Merriam Webster s Collegiate Dictionary to work jointly with others or together especially in an intell
289. ypes their gadgets are able to output information to and the portal server will only display these portlets to the suitable devices Internet Device Server IDS This is a server similar to the WDS It is designed to accommodate for new products as they emerge allowing the gadget writer to output information tailored to each device type The IDS detects which device the user is logged on with Open Security Architecture with LDAP integration The Plumtree portal claims a modular open environment for inclusion of multiple authentication sources Evidently the portal server synchronizes its user database with external sources Components called Authentication Source Providers 1s responsible for communicating with the authentication source The portal is delivered with such providers for standard LDAP directories and Windows NT domains The system also has integration for single sign on systems from Netegrity Oblix IBM and Securant Administrators can configure the synchronization feature to automatically give newly imported users a default profile This profile may depend on their group memberships The system can also read properties from the LDAP source and store this along with the profile When needed the server forwards this information to gadget web services as needed thus enabling them to consider the LDAP properties when rendering the portlet Searching All portal content is searchable using the Verity search engine which is in
290. ystems as these systems are supposed to make enterprise applications accessible through an easier interface and not to actually replace the existing application However productivity applications like calendar systems communication applications like e mail clients and front office applications like sales automation system can potentially be implemented directly as a portal application These applications would then replace other such systems As for vendor lock in the analyses show that vendors use the portal as another way to leverage their own solutions instead of trying to make portal systems interoperable 120 Modular Development Frameworks for Corporate Portals a Literature Review One exception from this can seem to be IBM where IBM developers have tried to make a common portlet API with the open source group Apache 11 5 Scalability All of the J2EE systems provided by the analyzed vendors are scalable enabling servers that can run on multiple physical servers The Epicentric and Apache Jetspeed systems needs a application server to run on however since they are standards compliant they inherit the scalability from the server on which they run The Plumtree system lets the developer choose whether each portlet should be run on a shared server alone on a physical server or spread out between multiple physical servers This feature makes the administrator able to put additional physical resources into the portlets th

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