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1. C Program Files GeoServer 2 0 1 data_dir j Cancel Figure 20 Setting GEOSERVER HOME and GEOSERVER DATADIR 48 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers B PostgreSQL with PostGIS Issues PostgreSQL supports capital letters in table and column names but it requires them to be quoted in queries Table 6 shows some examples of how the results return when the table names are norway and Norway Table Name SQL command Result norway select from norway Success Norway select from norway ERROR relation norway does not exist SQL state 42P01 Norway select from Norway ERROR relation norway does not exist SQL state 42P01 Norway select from Norway Success Table 6 Query problem in PostgreSQL 49 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers C Data preparation C 1 Export data from OpenStreetMap OSM To Export data from OpenStreetMap as shown in figure 21 visit http www openstreetmap Click Export tab select area of interest and then Export it as OpenStreetMap XML Data We will get one XML file with osm extension The structure of the file will probably look like in figure 22 PI OpenStreetMap COW http www openstreetmap org lat 59 9 516 amp z00m 10Rlayers BOOOFTFT
2. Separate destination for each source dataset Writer Format PostGIS LJ Dataset postgis Coordinate System Same as sour v L Mapping Files penStreetM ap OSM XML Translation Feature Processing Functions LJ Figure 23 Using FME to convert data and write data into PostGIS 53 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers C 3 Manipulate and optimize data with PostgreSQL 8 4 pgAdmin III After importing data into PostGIS we need to add a primary key into tables that we want to use with GeoServer otherwise we will get an error when we try to insert a new point as shown in figure 24 GeoServer needs a primary key defined on each table in order to make transactions work if our tables in the database do not have any primary keys we will probably need to add one for instance we can add a serial autoincrement primary key to our tabl After that we are required to reload the configuration and then we are supposed to be able to modify our data For example the auto increment primary key can be added as using the script below alter table tourism_point add column id2 SERIAL alter table tourism_point add primary key id2 lt xml version 1 0 gt ServiceExceptionBeport version 1 2 0 xmlns http www opengis net oge xmlns xsi http www w3 org Z001 XMLSchema instance x
3. 12941319 173424 4110122 686702 18367287 606576 11544180 703298 49 transform map displayProjection map projection 50 This code tells the map to zoom out to its maximum extent which by default is the entire world OpenLayers maps need to be told what part of the world they should display before anything will appear on the page Calling map zoomToExtent is one way to do this Alternative ways that offer more precision include using zoomToExtent and setCenter 59 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 8 Load the map 70 lt body onload init gt In order to ensure that our document is ready it is important to make sure that the entire page has been loaded before the script creating the map is executed We ensure this by putting the map creating code in a function that is only called when the page s lt body gt element receives the onload event OpenLayers Mozilla Firefox File Edit View History Bookmarks Tools Help E x e m http copernicus hig no 8080 geoserverfwww loc test htm 7 y B OpenLayers Base Layer O OpenStreetMap Mapnik Overlays Shops OpenStreetiMap 14 Next Previous amp Highlight all C Match case Figure 28 A page created from the given code 60 Using WFS T in combination with geolocation for online transactional editing of geographic features throug
4. 2 W3C Geolocation APIs can do the trick 1 Using OpenLayers library to show geographic data and edit geographic features OpenLayers is a pure JavaScript library providing for free as an open source It helps us to easily put a dynamic map in our web page with no server side dependencies To use Open Layers Javascript API we need to include OpenLayers js in our page The file can be stored on our machine or if we wish to always use the latest release of the script we should point a location of the file to http www openlayers org api OpenLayers js as shown below in figure lt htnl gt lt head gt lt title gt WFS T OpenLayers GeoServer PostGIS OSM lt title gt lt meta http equiv Content Type content text html charset UTF 8 gt link href default css rel stylesheet type text css gt won FL 4 5 6 8 lt script src http openlayers org api OpenLayers js gt lt script gt 9 pa lt script gt Eb Ke Figure 14 Include OpenLayers js in a web page Moreover some essential codes of OpenLayers that we need to use in this project are mentio ned below function description OpenLayers Layer WMS Create a new WMS layer object OpenLayers Layer Vector Create a new vector layer OpenLayers Protocol WFS Used to create a versioned WFS protocol to be used with OpenLayers Layer Vector 2 Using W3C GeoLocation API to gather a user s location We can loca
5. 3 Properties Allows access to Java Property files containing Feature information A Shapefile ESRI tm Shapefiles shp Gi Web Feature Server The WFSDataStore represents a connection to a Web Feature Server This connection provides access to the Features published by the server and the ability to perform transactions on the server when supported allowed Raster Data Sources A ArcGrid Arc Grid Coverage Format 8 GeoTIFF Tagged Image File Format with Geographic information ii Gtopo30 Gtopo30 Coverage Format A ImageMosaic Image mosaicking plugin A WorldImage A raster file accompanied by a spatial data file Figure 26 Available Data Sources 55 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers New Vector Data Source PostGIS PostGIS Database Basic Store Info Workspace w st 2 v Data Source Name Gjovik Description Geographic features in Gjovik Enabled Connection Parameters dbtype postgis host localhost port 5432 database postgis schema public user postgres passwd esee eoo Namespace http www hig no imt4901 project Figure 27 Data Info and Parameters of new vector data source 56 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers D OpenLayers Library OpenLayers is a ja
6. data It is an option to Oracle Enterprise Edition serving as a foundation for spatial infor mation systems It allows users to be able to manage geographic data directly in their appli cations and services As same as the reasons we used in making decisions in the previous steps due primarily to time constraints we would consider to use something that we know and it can work fine with our project In this case the author has worked with Oracle and PostgreSQL with PostGIS before though MySQL database can be useful and worked well in the project it is excluded as a candi date And between PostgreSQL with PostGIS and Oracle the author would prefer PostgreSQL with PostGIS due to it is Open Source software which means it is free of use 4 1 2 Client side A CLIENT WEB APPLICATION Since we want to see whether WFS T can be used in combination with geolocation on mobile browsers we need to develop a web application that can be used through mobile browsers Web browser are responsible for reading HTML documents then interpreting and showing them as web pages Therefore we plan to use HTML Hyper Text Markup Language a language for describing web pages to create interactive interface With HTML we can embed many scripts such as JavaScript JScript and ActionScript to make our pages more dynamic and more inter active By the way how can we make geographic information available on the Web or Which GIS tools we can use to put a map in
7. gt D amp View Edit History Export GPS Traces User Diaries log in signup Area to Export 60 8142 0 6402 The Free Wiki World Map 10 7077 0 7704 OpenStreetMap is a free editable map of the whole world It is made by people like Manually select a you different area OpenStreetMap allows you to Format to Export view edit and use geographical data in a collaborative way from 9 OpenStreetMap anywhere on Earth XML Data OpenStreetMap s hosting is o Mapnik Image kindly supported by the UCL O Osmarender Image VR Centre and bytemark O Embeddable HTML Other supporters of the project are listed in the wiki Licence OpenStreetMap data is Help amp Wiki licensed Under ths Copyright amp License Creative Commons News blog Attribution ShareAlike shop 2 0 license y Map key Permalin Shortlink Figure 21 Export data from OSM 51 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers lt xml version 1 0 encoding UTF 8 2 gt lt osm version 0 6 generator CGImap 0 0 2 A lt bounds minlat 60 7704 minlon 10 6402 maxlat 60 8142 maxlon 10 7077 lt node id 31264090 lat 60 7987 lon 10 6937617 user Helge Hafting uid 19565 visible true version 3 changeset 504536 timestamp 2008 01 01T19 12 002 gt lt tag k created by v Potlatch 0 4a gt lt tag k is_in v Oppland Norway
8. in the format of JPEG GIF PNG or SVG The client can easily view such images of the map through a web browser without needing to have any knowledge about how the data is stored or produced 2 1 2 WFS OpenGIS Web Feature Service WFS Implementation Specification is the main geospatial web service that provides an interface allowing requests for geographic features across the Internet no matter which platforms the clients are Similar to WMS once a client send a request to a web feature server asking for geographic data the server will provide geospatial feature data and send a response back in GML format More details about WFS will be described in the next chapter 2 1 3 GML Geography Markup Language GML is an XML grammar for describing geographic information It is well developed by the OpenGIS Consortium to express geometries and geographical relations serving transaction operations over the Web GML is also know as 15019136 5 GML can be divided into 2 parts including a GML document and a GML Schema This results to users and developers to be able to specific geographic features including points lines and polygons 2 2 Mobile Browsers As same as web browsers on personal computers web browsers designed to be used on mobile devices called mobile browsers Currently mobile devices have been involved in our daily lives many applications have been developed to be supported on mobile phones By the way each application has its ow
9. many new versions have been released accordingly with useful documents and examples available on its website Futher more OpenLayers has a powerful community behind it with users from many countries all over the world and its functionalities have been keeping on developing and growing e OpenScales 34 is a community driven mapping project implemented by a diverse group of people all around the world It is a user friendly interface designed for interoperability sup porting a variety of OGC formats and protocols such as WMS and WFS Moreover it allows us to build rich Internet mapping applications and manipulate geographic information OpenS cales was originally created from FlexLayers which was a Flex port of OpenLayers users who are familiar with OpenLayers can easily and quickly learn to use OpenScales because it offers many similarities to OpenLayers By the way the main difference between OpenScales and OpenLayers is that OpenScales uses ActionScript 3 and Flex while OpenLayers uses JavaS cript The first framework ArcGIS Web Mapping is proprietary while the others OpenLayers and OpenScales are open source all of them are provided for free Unfortunately ArcGIS Web Map ping can be used only if we implement an ArcGIS Server in our system So it is excluded from the list of candidates Now the choice stands between OpenLayers and OpenScales which both of them should be able to work fine in the project since they support a WFS protoc
10. the full WFS operations support INSERT UPDATE DELETE LOCK QUERY and DISCOVERY operations on geographic features using HTTP as the distributed computing platform 12 The protocol to be followed in order to process web feature service requests the following steps will proceed 13 1 A client application would request a capabilities document from the WFS 2 Aclient application optionally makes a request to a web feature service for the definition of one or more of the feature or element types that the WFS can service The client application generates a request based on the definition of the feature types The request is posted to a web server The WFS is invoked to read and service the request aA wg o When the WFS has completed processing the request it will generate a status report and hand it back to the client In the event that an error has occurred the status report will indicate that fact Moreover to support transaction and query processing the following operations are defined l GetCapibilities When a WFS gets this request it answers with a description of its capabilities 2 DescribeFeatureType A WFS can be asked to describe the structure of any of the feature types it serves 3 GetFeature A WFS can be asked to deliver features however the client should be able to constraint the query both spatially and non spatially and also specify what feature properties he she wants to receive from the WFS 4 GetG
11. 0 371 0 dev and later Once we open the application we will be asked whether we allow to be tracked our physical location If we consent then the next steps will be like what we already mentioned in Firefox e Safari version 5 and later The application works fine which our location can be detected and shown on the map e Internet Explorer As of now there is no support for geolocation in the current version IE8 Therefore once we launch the application our location will not be determined MOBILE BROWSERS e Android Browser Android browser supports the W3C Geolocation API As a result the application can work 37 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers well on this platform Similar to Mozilla Firefox we will be asked whether we allow the application to gather our location information as shown earlier in figure 15 and once we agree with it to do so our location is presented on the map as a yellow smiley icon e Safari on iPhone OS 3 0 and later Similar to Android browser the application can work well on Safari RQ 2 What are the main challenges to make use of WFS T in combination with geolocation on mobile phones To develop a prototype using OpenLayers library to deal with WFS T is not that hard but somehow some small problems could always happen And once the problems happen it takes quite some times until we can find th
12. Yes XLink WFS No Yes Table 3 WFS Classes Comparison Furthermore between WFS 1 0 0 and WFS 1 1 0 there is also a difference in the base GML schema used The OGC WES is one of the keys to GML deployment GML is used in both the re quest and response messages of the WFS The OGC interface offers standardized access to a feature data store and allows users to perform operations such as create update and retrieve GML fea ture data When a client sends a message requesting for geographic feature data to a WFS server a response message will be sent back to client in GML format However WFS and GML have been developed independently GML as a format file can be understandable by GIS applications and not completely served through OGC WES Therefore the versions of GML identified in OGC WES specifications are not the most recent versions of GML available 15 WFS 1 0 0 shall conform to GML version 2 1 1 as a minimum version for the identified WFS version while 16 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers WES 1 1 0 shall conform to GML version 3 1 1 as a minimum version for the identified WFS version 17 Sandra F llman mentioned in her master thesis Using WFS to build GIS support 10 that du ring the period she implemented her project in 2004 WFS was quite new and many negative aspects due to the functionality of WFS were hidden only general inf
13. bas x adu RemU CETERI qu qd ores 24 cT 27 LEE os Revue e UR UA EEUU Ue e RRO dc RSE EE ES ERS 27 4 2 2 Testaj ica a aa AAA te RUE we E Rm cmn 32 Truc 37 5 1 Results ae eee eee o BASS EERE Ou EG ASHER OR UR d 37 T 39 6 Future Work oir rra a e CA ORR RO a 41 Bibliography ee 43 Tcr 47 a eos a F 49 C Beale ww a BARE ee ee ew SI SS epee 51 C 1 Export data from OpenStreetMap OSM ooo o eee 51 cere reece 53 C 3 Manipulate and optimize data with PostgreSQL 8 4 pgAdmin II 54 vii Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers C 4 Create Workspace and Store in GeoServer D OpenLayers Library E_W3C Geolocation API F A client application viii 55 57 61 63 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 1 Introduction If someone asks you what map is how do you answer the question You may think about an image of the world including some regions each region contains many countries Or you may think of the shape of your country pinning the city you live on that Moreover if you are a traveler you may think that map is something that can provide you information about sight seeings including how to be there We can see that maps are a powerful way of thinking about
14. demo system level 2 as mentioned in chapter 2 Related Work since it was proved in her project Using WFS to build GIS support that the implemented system worked fine and no problems occurred Therefore we need GIS servers serving as a map server and a WFS server a spatial database providing geographic features a client application and in addition mobile phones that can use to access to the Internet However we decided not to use exactly the same platforms as the demo system of Sandra since the number of available GIS products in the market has been increasing each day Therefor to make a decision which services platforms will be used the investigations are made as discussed in greater details in the following sections Server side Client side A client web application A map server A Spatial A WFS server DB Figure 10 Requirements for a test system 4 1 1 Server side A MAP SERVER Since in this project we mainly focus on implementing WFS T so we consider to use available map images which there are such a variety of them in the market today And candidates belong to Google Maps Bing Maps and OpenStreetMap all of them are well known and providing interfaces to extensive mapping e Google Maps 19 is one of the most famous web mapping service applications owned by 19 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Google Similar
15. geolocation enabled to work on every framework seems not possible at this time RQ 3 To what extent are map and geographic features can be displayed on mobile brow sers Since mobile phones have small screens the main challenge of the implementation based on showing geographic information is belong to how to compose a suitable map image From the test we found that either a base map layer OpenStreetMap or overlay layers Shops and Cur rent Positions can be shown successfully on mobile browsers as in this case we mainly performed a test on Motorola Milestone Android which its screen size diagonal is 3 7 Moreover some limitations while running the application on mobile phones have been revealed such as it is not easy to select the geographic features green dots especially in case that two dots are close to each other Additionally it is also not easy in order to zoom or pan the map due to the same reason as earlier buttons are close to each other 38 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 5 2 Conclusion While using WMS returns geographic data as maps WFS can return results in various formats such as GML KML and shape files Therefore we can say that WFS is more flexible due to it offers users to play with the output and can write their own queries to get the geographic information they need WFS T is an extension of WFS which one obvio
16. org 25 type png getURL osm_getTileURL 26 displayOutsideMaxExtent true 27 attribution lt a href http www openstreetmap org gt OpenStreetMap lt a gt 28 F 29 30 var saveStrategyPoint new OpenLayers Strategy Save 31 var shops new OpenLayers Layer Vector Shops 32 strategies new OpenLayers Strategy BBOX saveStrategyPoint 33 projection new OpenLayers Projection EPSG 4326 34 protocol new penLayers Protocol WFS 35 version 1 1 0 36 url geoserver wfs 37 featureType shop point 38 srsName EPSG 4326 39 featureNS http www hig no imt4901 osm 40 geometryName geom 41 42 H OpenLayers organizes a single map into several layers This part of code tells OpenLayers that we want to create two new layers in this case including a map layer osm and a geographic feature layer shops which they can be referred to elsewhere as osm and shops 5 Add layers to the map 44 map addLayers osm shops This step is to add the created layers in no 4 osm and shops to the map 6 Create a layer switcher 45 map addControl new OpenLayers Control LayerSwitcher This step is to create a layer switcher control to the map Since earlier in the code two layers are added to the map we will see that OpenStreetMap Mapnik and Shops are listed in the control 7 Position the map 46 map zoomToExtent 47 new OpenLayers Bounds 48
17. project with the slogan The free encyclopedia that anyone can edit In the same way OpenStreeMap is a collaborative project with the slogan The Free Wiki World Map It allows users to manipulate geographic data on the maps in a collaborative way no matter where they are The project was started because most maps we think of as free actually have legal or technical restrictions on their use holding back people from using them in creative productive or unexpected ways 21 Since everyone can take part and join the project some parts of the map in OpenStreetMap may contain more detail than other services because they may be updated by local people who live in and or are familiar with the areas Additionally not only we are able to manipulate geographic infor mation on the map but we are also able to download and use all data from OpenStreetMap for any purpose under an open source license The web map services above basically provide almost the same features which in this case we mainly concern on a map layer Figure 11 illustrates the map images of the city of Gj vik Norway from different sources Google Maps Bing Maps and OpenStreetMap respectively We can see that all of them provide maps with something in common such as the layouts of the maps road names and railway signs However OpenStreetMap is the chosen service as it is a collaborative work which people all around the world can participate some areas of the based map especially
18. seuoud jo siueuigos e sesse1ppe se go4gq gf surrope d M91g pue 9 IGOJA SMOpurM uerqui amp s nurT Areyatidoid eurSug JIasmoig sgl PAIAUIO JosMOoJg sal S930N SUDJ DIBMIJOS dUIsUd MOAR JU9IIMD 1038217 JosMOJg 11 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 2 3 Geolocation Geolocation is a combination of the words geographic and location It is the labeling of the geographic location of an object in the real world Geolocation is a process that helps to deter mines where a user is located by making use of a user s device For example when a user uses her computer to connect to the Internet geolocation can tell the position of the user by a user s IP address Additionally if a user connects to the Internet through her mobile phone geoloca tion can figure her location by using a network provider and or a GPS provider 8 Name of a network provider can be used to determine location based on availability of cell tower and WiFi access points which results are retrieved by means of a network lookup On the other hand name of a GPS location provider can be used to identify postion using satellites Find me N Figure 5 When you connect to the internet through your mobile browser geolocation can figure your location by using a network provider or a gps provider 12 Using WFS T in combination with geolocation for online transactio
19. to other Google services JavaScript is greatly used in implementing Google Maps Moreover Google offers Google Maps APIs to allow users to manipulate Google maps and embed the maps on their own pages Google Maps was launched by Google on February 8 2005 and has always been released new features since then for instance Google Bike Maps allows users to search for biking directions on Google Maps Google My Maps allows users to put their information on Google Maps by using geometric shapes such as points lines and polygons Google Street View allows users to see maps based on panoramic street level views and so forth Google Maps is proprietary software and provided for free for non commercial use e Bing Maps is a web based service developed by Microsoft To implement Bing Maps Microsoft has used their own technology called MapPoint Web Service And similar to Google Maps Microsoft provides a set of APIs that enable users to manipulate Bing Maps for ins tance users can integrate Bing Maps and location functionality into their own Web site Mo reover users are able to work with the Bing Maps Platform for free but the use of the maps must be on public facing without password protected Web sites and the limitation to access in a 12 month period is no greater than 125 000 sessions or 500 000 transactions e OpenStreetMap 0SM is created by Steve Coast in 2004 under the inspiration of the famous site named Wikipedia which is a collaborative
20. web browser with geolocation enabled and then we can see our location including the points of the nearby restaurants on the map In the future based on the created prototype some modules can be implemented to enhance the functionalities such as to make users log on before using application to make users upload their files pictures voices comments related to the places and so forth Additionally few solutions of determining loca tion of users from using web browsers have been published at present Each solution has its own limitations if we can find the way to make them work together especially to be able to perform in every platform that will be nice 41 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 1 2 3 4 5 6 7 8 9 10 11 12 13 Bibliography Krygier J amp Wood D Making maps a visual guide to map design for GIS p 3 The guilford press 2005 ISO org ISO TC211 http www iso org iso iso catalogue catalogue tc catalogue tc browse htm commid 54904 Visited Jun 2010 Opengeospatial org OGC standards http www opengeospatial org standards vi sited May 2010 SEWilco 2007 Ogc standards help gis tools communicate http commons wikimedia org wiki File Geoservices server with apps png Visited May 2010 Portele Clemens ed August 2007 OpenGIS Implementat
21. O uorssa1dxe y 10 1ISMOI q9M 92uo81oAu07 K1e3oridoid ALIUJ So ejueq Jos MOJg JO IES39N suopegd uonrpg RS 8 pig OOS UBIQUI S x 9 8 9 Iqo A SMopurM si1oddns pualmo juo1uoo 143119A IS pue xefy OT USe 4 SISpudyY Areyatidoid OX225 SIY NS IISMOIG IJIOJA SIY NS yono pod pue auoyd uo Areyotidoig WAM 241 jddy Leges souoyd ueur uo pe e3sur suea15s pews 103 JeULIOJaI pue TIA LH 3UIpea1 jo ajqedey Arejatidoid 01S91d 91eM3Jos e1edo 9mqom e1edo AV e9a aL Aq paumo OOT Atezortido1d gv 031q0 IISMOIg 03190 Azejatidoid APM EJON IISMOIG Op SOLIS PD ON Atezotido1d JUOIION PIT OD SSHDOV WUOLDON Gniqam asn 19SMOIF 9 Iqo N SAEMUIAN 8007 ut saemuado toy paamby Atezorido1d 0 UOISISA JX9N N3NH dnos pes SNOIA91d 195MOJg DELI JA xnurT 10 9 Iqo A SMODUIM S31oddns 193U0 ON UONOJA ur yote s y Aq parmboy Azejatidoid IDIGEM DUL AJGOJA YIIOL J9SMOJg SHJ Areyatidoid 3joso3orj i 9 IqoIN 1910 dXH PUIUL Jaye 10 Plorpuy 103 3ueutdo oAop TZ 1491 NND 193 10 Qc UI pue OWL PRJON 10 paseajer pu9Imo TdD IND 19 10 T TAN OX225 UZON 9 Iqour 103 XOJA K1e3oridoid o8ue A UOO ur t21easoq JosMO1g LIoq Id K1e3eridoid IMM wed IasMOIg SOG2M ZA Td pue Q z oqedy WAM 218005 JosMOJg proIpuy Areyoudoig qUOIJION woo uozeuly q9M ISPG APUN 239 ealoy CUYD YSN ur euod remp pue suoydyews 139470 X Z IA APM pu VWi42O0A SINUO OT Bunsures enpoN Areyatidoid X 9 A rumT OUI 9IEMEJUT J9SMOJg SLIe Od euoudireurs pue suoyd 213894
22. O standard GIS allows us not only to create maps but also to manipulate important information on maps Information in this case can be any things in the real world for instance parks rivers schools houses and so far Each category can be stored separately in different layers as shown in figure 2 When we move to a new house we may want to know the nearby places We open a GIS applica tion and send a request to a server asking for a map of our area Then the server finds geographic data as we request renders all together as one image and finally sends a respond back to us This is an example of using Web Map Service WMS one of the most famous OGC standards which has been widely used for some years Anyway while all we get from using WMS is a picture using Web Feature Service WFS offers us a chance to do something more than just to look at the map all we get from using WFS is actual vector data as XML It can be seen that WFS provides us greater control for the ways we are able to play with the raw geographic data including query data and or manipulate insert update and delete data From the previous example when we move to a new house we may want to know nearby supermarkets Then we submit a query to a server Once the server finds related data to our request it compiles the data and sends it back to us as GML file in this case the GML file contains information about nearby shops After that the application validates the file
23. Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Yaowapa Pornsamutsin Master s Thesis Master of Science in Media Technology 30 ECTS Department of Computer Science and Media Technology Gjovik University College 2010 Avdeling for informatikk og medieteknikk H gskolen i Gj vik Postboks 191 2802 Gj vik Department of Computer Science and Media Technology Gj vik University College Box 191 N 2802 Gj vik Norway Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Yaowapa Pornsamutsin 2010 06 20 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Abstract While online maps have been widely used in the society the number of providers who develop applications to serve those users needs have also been increasing To make use of data or ex change data from each provider some standards are involved The OpenGIS Consortium OGC is an association offering certain standards for geoprocessing which can be helped in developing and implementing software The purpose of this project is to use WFS T in combination with geolocation for online tran sactional editing of geographic features through mobile browsers on mobile phones based on one of OGC standards called WFS Web Feature Service which WFS T Tra
24. _server Visited May 2010 Deegree org Deegree http www deegree org Visited May 2010 GeoServer org GeoServer http www geoserver org Visited May 2010 ESRI com Arcgis Server http www esri com software arcgis arcgisserver Visited May 2010 Postgresql org PostgreSQL visited May 2010 refractions net PostGIS visited May 2010 MySQL com MySQL visited May 2010 Oracle com Oracle visited May 2010 ESRI ArcGIS Web Mapping visited June 2010 OpenLayers org OpenLayers http openlayers org visited May 2010 44 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 34 Openscales org OpenScales visited June 2010 35 Google Google Loader google loader ClientLocation Hhttp code google com apis Visited June 2010 36 Google Google Gears for Mobile Geolocation API http code google com apis gears api geolocation html Visited June 2010 37 W3C Geolocation API http dev w3 org geo api spec source html visited May 2010 38 FME Desktop ESRI Edition FME Universal Translator http www safe com visited June 2010 39 V vra M January 2009 Interface design for mobile devices Cork Institute of technology 40 Cook J Web Mapping Course Notes http www maths lancs ac uk stantonm Web_ Mapping Course Notes pdf Visited June 2010 45 Using WFS T in combinati
25. and draws vector for us As a result we can see the nearby shops on a map WFS basically supports read only operations WFS that allows us to insert update and delete geographic features called WFS T Transactional Web Feature Service Once again refer to the example earlier when we get the filtered data by location shops around our house from the server if our application supports WFS T we may be able to edit geographic features such as add a new shop via the application interface without the infrastructure requirements Further more at the present of time there is a technology available called geolocation API which makes Web browsers can determine user s location based on the used devices It can be noticed that this kind of technology is helpful in GIS application development since the browsers can detect user s location and then the GIS application can make use of the positioning of users For example in this case if we use the web based GIS application to find the nearby shops once we open the program on Web browsers we can see the requested places including our location pinning on the map Currently there are many GIS applications available while some are commercial some are Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Figure 2 GIS consists of map layers provided for free Moreover not only we are able to use those tools on powerful computer
26. ao uses his mobile phone launching a web ap plication via his mobile browser the application asks whether he allows it to gather his location information which he accept the request and few minutes after that he shows what are displayed on his mobile screen to her As a result Jasmin sees a map with some symbols marking on which she can understand that a yellow icon represents her location while some green dots are nearby stores Xiatao tells her that he often uses the application to search for nearby stores and once he discovers that the shop he visits is new and not on the map he will add it through the application On the other hand if he knows that a shop is no longer open or moved to a new place he will either delete or update its location on the map Jasmin says thank you to Xiatao and plans to use her mobile phone to connect to the application to discover Gjgvik Additionally she tries to use the application on her personal computer and sees that it can work fine through Firefox 32 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers m BORO 121 http copernicus hig no 3030 geoserver wen loc p fy Bal copernicus hig no 8080 wants to know your location afl Remember preference a lw le lr lat ls lp le E lz lx gt le ll alle Figure 15 Xiatao is asked to share a location when running the application through a mobile browser on hi
27. arts including 1 SERVER SIDE and 2 CLIENT SIDE The first part contains a map server which OpenStreetMap is selected to be used to provide a map image a WFS server which GeoServer is chosen for providing geographic features and lastly a spatial database which PostgreSQL with PostGIS is picked to be used to store geographic information On the other hand for client side OpenLayers is selected to be used to implement a web based application and Motorola Milestone is chosen to be used as a test device Server side Client side A map server A client OpenStreetMap web application OpenLayers A WFS server GeoServer A Spatial DB PostgreSQL with PostGIS Motorola Milestone y Sy An overview of system components 4 2 1 Preparation SERVER SIDE 1 Installation e GeoServer was started in 2001 and has been developed and released continually As of May 2010 the latest version of GeoServer is 2 0 2 released on May 25 2010 By the way GeoServer 2 0 1 is selected to be used in this project as it was the latest stable version released during the time we started doing the project GeoServer offers many choices as installation methods including using OS independent binary using Web archive and using Installer In this case we develop our project ba sed on Windows OS so the easiest way seems to be using Windows Installer After we download and run the installation file the operations took only few minutes more infor
28. cluding its detail on a web page To answer the questions an investigation of the following products are made e ArcGIS Web Mapping 32 by ESRI is a collection of APIs providing a solution for us to create interactive web applications The term Web APIs primarily refers to the JavaScript Flex or Siliverlight APIs which all of them allow us to add content to the map via online services build stand alone applications connect to GIS servers and so forth For implementing cost development and deployment with the APIs are free but the latter can be done under certain terms and conditions By the way to use ArcGIS Web Mapping we need to have an ArcGIS Server available whose maps and tools we can use in our application e OpenLayers 33 is a free open source framework with the slogan Free Maps for the Web It is a JavaScript library which not only allows us to display geographic information in web browsers but also provides an API for creating rich web based geographic applications In 24 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers OpenLayers map tools are separated from map data so we can use all the tools to implement on all the data sources this helps to fix the lack of interoperability Moreover it supports open standards and protocols for geographic data access such as WMS and WES The initially release of OpenLayers was launched in June 2006 After that
29. ctional editing of geographic features through mobile browsers 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 Jody Garnett and Brent Owens 2003 Validating Web Feature server Design Document Chris deJager AMEC Earth and Environmental Technology Business Unit 24 May 2006 Web Feature Services Considerations for CGDI Government Partners version 1 0 Cox S Cuthbert A Lake R and Matell R eds April 2002 OpenGIS Implementa tion Specification 02 009 OpenGISGeography Markup Language GML Implementation Specification version 2 1 1 Cox S Daisey P Lake R Portele C Whiteside A eds January 2005 OpenGIS Imple mentation Specification 02 023r4 OpenGISGeography Markup Language GML Imple mentation Specification version 3 1 1 Selid Knut WFS T and Mobile Clients Master s thesis Department of informatics Uni versity of Oslo Norway 2006 Google Google Maps http maps google com visited June 2010 Microsoft Bing Maps http www bing com maps visited June 2010 OpenStreetMap org OpenStreetMap OSM http www openstreetmap org visited May 2010 Wikipedia com Wikipedia http en wikipedia org wiki Wikipedia visited June 2010 Mapserver org MapServer http www mapserver org Visited May 2010 Mapserver org MapServer WES Server http www mapserver org ogc wfs
30. e 30 After that she will see a map with some symbols A yellow smiley icon represents her location while green dots represent nearby shops Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 3 The below code shows a background process for requesting geographic features from a WFS server 1 1 0 xsi schemaLocation http http www w3 orq er lt wfs getfeature xmlns wfs http wins opengis net wfs service WFS vers www opengis net wfs http schemas opengis net wfs l 1 0 wfs xsd xmlns 2001 XMLSchema instance feature shop point c http www opengis net ogc sName EPSG 4326 xmlns feature http www hig no imt4901 osm wfs query typeName lt ogc filter xmlns lt ogc bbox gt lt 0gc propertyname gt geom lt oge propertyname gt qnl envelope xmlns gml http www opengis net qml srsName EPSG 4326 gt lt gml lowercorner gt 332 1132 912 104 88306911346 lt qml lovercorner gt lt gml uppercorner gt 380 85552 241 135 26592890733 lt qml uppercorner gt lt gml envelope gt lt oge bbox gt ogc filter wfs query x wfs getfeature 4 The below code shows a background response from requesting geographic features from a WES server lt wfs featurecollection number fFeatures 9 timeStamp 2010 07 01T20 32 12 2904 02 00 xsi schemaLocation http copernicus hig no 8080 geoserver
31. e been increasing each day we may need to concern about what information we are going to share and how much we can trust the websites that ask for our information 39 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 6 Future Work WES T is not new but it still not widely used While geolocation is a new technology that becomes well known and useful this days The implementation of WFS T in combination with the geoloca tion technique for mobile browsers seems not much published Therefore to develop a prototype in this project seems to be interesting considering that there are now no similar web applications for mobile browsers available in the market However due primarily to time constraints we cannot include all features of WFS T in our project Currently with a rapid growth of mobile technology new modern mobile phones have provided many functions for example we can use our mobile phones to listen to MP3 record a voice take a photo buy a movie ticket book a ho tel and so on Moreover many smartphones now include built in GPS receivers that means we are able to use map no matter where we are And as a result many applications can make use of the new technology to estimate our location and provide some useful information that we may be interested such as when we travel to one city and want to get some information about nearby restaurants we can just open a
32. e called map osm including Nodes Ways Relations and Tags in the file 2 Mapnik Image offers map images in the default of OpenStreetMap style called Mapnik A set of image formats includes PNG JPEG SVG PDF and PostScript 3 Osmarender Image similar to Mapnik Image allows users to export a map image but in a different style which is called Osmarender We can decide to export map images in PNG or JPEG 4 Embeddable HTML allows us not only to embed the map in our website but also to mark a specific location on the map As a result we will get an output text containing a link which looks similar to the following http www openstreetmap org lat 60 79425 amp lon 10 686485 amp zoom 14 amp layers BOOOFTFT In this case we need a raw geodata so we select to export OSM data as OpenStreetMap XML data Once we export data from OSM we will get an osm file in XML format with related geographic information such as vector features inside the area we specify in the map The output file contains similar syntax like the following 28 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers lt xml version 1 0 encoding UTF 8 lt osm version 0 6 generator CGImap 0 0 2 lt bounds minlat 60 78605 minlon 10 67069 maxlat 60 80245 maxlon 10 70228 gt node id 490165001 lat 60 7948358 lon 10 6893501 user Kagee uid 46430 visible true version
33. e initiated through the WFS 15 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers call and they all support the internal functions of transaction and query processing We can see that the only difference between two versions is that WFS 1 1 0 has the ability to perform an operation called GetGMLObject However this function was implemented in WFS 1 1 0 which is related to XLink and Transaction classes Table 3 shows the comparison of WFS classes between two version 1 0 0 and version 1 1 0 Each class can be described as below e Basic WFS supports the read only operations including GetCapabilities DescribeFeatureType and GetFeature e Transaction WFS supports all operations of a basic WFS and in addition itincludes a Transation operation Moreover this class can also optionally implement GetGm10bject and LockFeature operations e XLink WFS as same as a Transaction WFS class supports all the read only operations and in addition it includes a GetGmlObject operation for local or remote XLinks and provide the option for this operation to be activated during GetFeature operations Operations WFS 1 0 WFS 1 1 0 GetCapabilites Yes Yes DescribeFeatureType Yes Yes GetFeature Yes Yes GetGmlObject No Yes Transaction Yes Yes LockFeature Yes Yes Table 2 WFS Operations Comparison Classes WFS 1 0 WFS 1 1 0 Basic WFS Yes Yes Transaction WFS Yes
34. e solutions In this project when we have a problem the OpenLayers community including the mailing lists are very helpful especially for those new users who want someone to help fixing their problems However Dean and Jim mentioned about the AAA slogan in their book Semantic Web for the Working Ontologist Effective modeling in RDFS and OWL that on the World Wide Web Anyone can say Anything about Any topic which means people are free to write a page saying whatever they want and then publish it through the In ternet No one can guarantee that what we have seen on the public web board is completely correct Though the open source software like OpenLayers and GeoServer have been used by many people when we find an error and post the problem on the Internet forums we are not able to force anyone in the community to help answer your question It is not like using commer cial software in which when you have a problem you can contact the technical support regarding the software product and may get a response back in short period Moreover in some cases we can see that documentations of some open source products are unclear or not well structured with grammar errors This kind of problems can lead new users to feel that it is hard to learn to use software Additionally since geolocation is a new technology not many users realize about it or understand how it works Moreover not all browsers support geolocation So to implement the application with
35. e the main challenges to make use of WFS T in combination with geolocation on mobile phones Creating and testing a prototype definitely help us to answer this question because we can experience unexpected problems and difficulties during the implementation RQ 3 To what extent are map and geographic features can be displayed on mobile browsers We are able to see how good geographic data can be shown on the screens when we perform a test So to answer this question implementing a prototype is a must After we set goal of the project to build our own GIS system we need to investigate the current environment with available GIS tools in the market for instance we may want to have a GIS server a spatial database with geographic data and some GIS tools in this project we mainly Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers concentrate on using open source software The investigations of platforms are made After that the test environment is setup with the provided geographic data from different free and well known sources The whole point of a mashup a combination of features and or data from more than one source to develop a new useful service is to make use of available GIS technology to provide a web based application allowing users to do online transactional editing of geographic data through their mobile browsers After the testing the results are a
36. er and so forth ArcGIS Server is commercial software developed by ESRI It supports interoperability 21 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Key Value Comment Rendering Photo Important roads that are not motorways Forflights of steps stairs on Astreet where pedestrians gt have priority over cars children highway living street can play on the street maximum speed is low Forroads used mainly highway pedestrain exclusively for pedestrians shoppingareas highway dewa Atrack is a route that is Y Y separate fromthe road CarPark Nodes and areas will amenity parking geta parking symbol Areas will be colored Open greenareafor recreation usually municipal Fortowers or pylons carrying high voltage electricity cables Normally constructed from steellatticework Aghihouse outa light beamto guide Figure 12 Example features in OpenStreetMap 22 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers standards such as OGC and W3C Moreover it also supports integrated development envi ronments such as Microsoft Visual Studio Eclipse and NetBeans However ArcGIS Server is commonly used by organizations that want to distribute their own geographic data The comparison of each product is made as shown in table 4 Compari
37. es and so forth W3C Geolocation API has been developed based on earlier work such as Geolocation in Fireforx and Beyond Gears Geolocation API and LocationAware org To use this API neither an API key nor an installation are required However regarding security and privacy considerations users will be asked whether they want to share their locations when they load the application via web browsers this is to ensure that no location information is done though the API before users allow it to do so All of the above APIs are provided for free and seem work fine in this project However we decide to use W3C Geolocation API in this project since there is no work required before using it compare to the first two APIs Google AJAX and Gears which we either need to register for an API key or install a tool on our computer first Futhermore for a client device we plan to make a test on Motorola Milestone since it is sponsored by our school Its operating system is Android 2 0 with some nice features support including web browser with location enabled aGPS 3G and so on 26 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 4 2 Implementation After the investigation of platforms figurd10 is filled up with selected products which the figure below illustrates the results showing an overview of what we are going to implement in our system We categorize the system into 2 p
38. esults can be displayed successfully on mobile phones He developed a prototype system called SMILEX including server side SMILEX services and client side SMILEX client For the SMILEX services he implemented both WMS and WFS 17 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers on the same platform using GeoServer while MySQL was used as a data storage For the SMILEX client it was developed on Java 2 Micro Edition J2ME Moreover the JSR 179 location API was implemented to achieve a user position from making use of a GPS receiver on a mobile phone The figure 9 below presents an overview of a communication in the SMILEX system It allows users not only to ask for spatial information but also to perform transactions insert update delete on geographic features through mobile phones WFS requests Mobile sm Client WMS requests WFS responses WMS responses WMS Figure 9 Prototype Communication Overview 18 18 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 4 Research and Implementation 4 1 Investigated platforms Since the main idea of this project is to find out whether WFS T can be used in combination with geolocation to edit geographic features online via mobile browsers To setup a test environment we decided to create based on Sandra s
39. features As in the project the following issues are performed e Review of Web Feature Service Implementation Specification OGC 04 094 version 1 1 0 mainly focusing on WFS T section e Investigate previous work about how WFS and WFS T are used what are advantages and disadvantages of implementing them e Develop a prototype using OpenLayers library in combination with geolocation API to build a web based geographic application which GeoServer is installed as a GIS server and Post Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers greSQL with PostGIS is used as a datastore connecting to GeoServer e Test editing of geographic features through mobile browsers and analyze the results 1 2 Keywords Geographic Information Systems GIS GeoServer OGC web services WMS WFS WFS T Mo bile browser Geolocation 1 3 Problem description Recently there are numbers of open source GIS applications that offer for free Comparing to proprietary software the most advantage of using free software may be that it can help orga nizations to save their cost such as in licensing fees and upgrading fees However it may also provide some disadvantages if we choose the wrong one that is not fit to our projects And nowadays Web Map Server WMS is one of the most important services that has been widely used in GIS systems It allows users to request for geographic data which w
40. give readers some background information about geolocation the OpenGIS Standards including concepts and technologies of GIS and mobile browsers how the prototype is created and also the results of the implementation to provide information for those who are interested in using WFS T to edit geographic features through web browsers on mobile phones iii ugh mobile browsers ctional editing of geographic features thro mbination with geolocation for online transa Using WFS T in co Acknowledgements Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Contents ad da aaa a dol des a oia iii Acknowledgements ee ss v GoOntents 5 cj lt a kee we e ii a A a Vii 1 Introduction zn et a he Edu ada da dae 1 esp Sr Spe ter o 3 seras 4 4 Boats Had gh eee ence 4 Mur ee ee eee eee ee Te eee 5 e a eee the ed aaa deed 5 7 7 9 9 9 9 2 Backeround lt sso sea a e as 2 1 OGC Web Services aoaaa a 2AL WMS 2b bbe aa ee eee x A 212 WES sg acces lv eee ee ae ee US aoe E a Oh ee s ZAS GMI eased ee a Ro Ee e Be ee Bee eo we we a me ee Ga 2 2 Mobile Browsers 2 4 dedos ox york api wei ESE EE OS OE RE es E MENO Papia c Ur EL ME aru aee iens ua 12 3 Related Work 22e sh 13 4 Research and Implementation o e e eee 19 4 1 Investigated platforms o e e 19 EAS AAA 19
41. gt lt tag k name v Gj vik gt lt tag k place v town gt lt tag k source v earth info nga mil gt lt node gt lt node id 35135172 lat 60 8885449 lon 10 6765891 user kao uid 68830 visible true version 6 changeset 3423173 timestamp 2009 12 21T21 22 172 gt lt node id 35135174 lat 60 8892949 lon 10 6773391 user kao uid 68830 visible true version 6 changeset 3423173 timestamp 2009 12 21T21 22 172 gt lt node id 35135176 lat 60 8905449 lon 10 6770891 user kao uid 68830 visible true version 6 changeset 3423173 timestamp 2009 12 21T21 22 17Z lt node id 35135178 lat 60 8902949 lon 10 6758391 user kao uid 68830 visible true version 6 changeset 3423173 timestamp 2009 12 21T21 22 172 gt Figure 22 An example of XML data from OSM 52 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers C 2 Convert and Import data using FME Universal Translator Converting OSM XML data and importing the converted data into PostGIS database through FME Universal Translator can easily be done by setting Translation parameters as shown in figure Set Translation Parameters Reader Format OpenStreetMap OSM XML v E Dataset DAMy documentsimap osm EJ Coordinate System Read from so v Multiple Source Dataset Options Merge source datasets to one destination
42. h geolocation for online transactional editing of geographic features through mobile browsers google loader ClientLocation which allows our application to acquire a user s location based on a user s IP address In general this method can expose an approximate location of the user but sometimes it is unable to locate users especially for those who are behind an anonymous proxy or may return us inaccurate location based on IP address geolocation providers Additionally to use this solution we need to sign up for an API key which is provided for free e Gears API by Google provides a Geolocation API allowing our web application to gather a user s geographical position by using the getCurrentPosition method which it is able to determine the user s location by using a set of data such as the user s IP address and WiFi nodes Moreover the Gears Geolocation API is now capable to use WiFi antenna data to provide more accurate position data Google Gears is an open source project that enables us to create powerful web application by providing many new features for us to add to web browsers However to be able to use Gears API an installation of Gears on a computer may be required e W3C Geolocation API by W3C the well known organization for the World Wide Web offers a way to gather a user s location by associating a geographic location with a hosting device like Global Positioning System GPS IP address RFID WiFi and Bluetooth MAC address
43. h mobile browsers E W3C Geolocation API From the W3C Geolocation API Specification 37 it defines the Geolocation API as an API that provides scripted access to geographical location information associated with the hosting device The following code is an example of how we can use Geolocation API to detect a geographic location if navigator geolocation navigator geolocation getCurrentPosition function position alert Your geographic coordinates latitude position coords latitude longitude position coords longitude H else alert Your browser does not support Geolocation API To find out whether our browser support Geolocation or not an object called navigator geolocation is used Once we launch the page in case that our browsers support Geolocation we will be as ked if we will allow the application to get our location information figure 29 If we accept the request the browser will gather the information and provide a position object in this code there will be a pop up window informing us our geographic coordinates figure 30 On the other hand if our browsers do not support Geolocation we will get a pop up window telling that our browsers do not support this feature figure B1 OpenLayers Mozilla Firefox File Edit View History Bookmarks Tools Help M x A B http copernicus hig no 8080 geoserver www locjtest html B OpenLayers e copernicus hig no wants to kn
44. he other places we open Google Maps and input texts to get the directions and map Nowadays there are lot of providers who have developed and provided this kind of information in the market how can we combine data from Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers different sources As same as in our society that we have some rules we need to follow to make us can live happily together in GIS world to make one product datum to be used with the others the implementation has been developed by following the OpenGIS Standards OpenGIS gjis a Registered Trademark of the Open Geospatial consortium Inc OGC This organization is similar to the World Wide Web Consortium W3C which has developed Web standards both OGC and W3C may be comprised of many organizations such as commercial government research university and so forth The difference between the OGC and ISO International Organization for Standardization is that ISO has provided of International Standards supported by law and its organization is only at the National level without membership by any organizations The OGC can submit OGC standards for approval as ISO standards under the terms of the agreement with TC211 Geographic information Geomatics 2 Recently the OGC standards baseline comprises 30 standards and for some standards such as WMS SF and GML are already complied with the requiredments of IS
45. ified as software libraries web servers desktop GIS spatial databases and GIS viewer 9 While a lot of research groups have established their stand in the open world users have to consider whether they can use data from different sources To make standard solution in GIS software developing the Open GIS Consortium OGC free software legend O term domain license types GPL amp LGPL ih OC property l MIT lice JEU c t TITRE free for BSD license dewmoad Shareware E i AA A E open source software proprietary software Figure 6 Terms used with respect to software licenses 9 13 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers provides two programs OGC Specification Program and OGC Interoperability Program for the planning developing reviewing and last of all officially adopting the specifications In this project Web Feature Service Implementation Specification will be involved 11 The Open Geospatial Consortium Inc OGC is an international industry consortium of 388 companies government agencies and universities participating in a consensus process to develop publicly available interface standards http www opengeospatial For the project implementation we will mainly focus on performing transactional operations since we are curious that why WFS is not used through a wide area as WMS WFS T is a part of WFS
46. ill return re sults as map images Many GIS tools support WMS while many of them do not support WFS T However one good obvious issue of WFS T is that it supports not only all operations of a basic WFS which allows users to get raw geographic features over the Internet but also a transaction operation which allows users to modify geographic features This benefit makes some providers and developers concern to implement WFS T in their systems Recently there are some applica tions that already support WFS T by the way many of them are not be able to run on mobile devices So in this project we are going to research about how WFS T in combination with a new technology like geolocation can be used together to perform editing of geographic fea tures via mobile browsers on mobile phones and investigate advantages and disadvantages from implementing it 1 4 Justification Motivation and Benefits From the introduction and problem description above since there are various GIS applications provided for free as Open Source software it is more comfortable for us to think about how we can develop the prototype because we do not need to concern much about the implementation cost in case that we choose to use Open Source tools At the present of time many research papers have involved in WMS area While some of them have been related to WFS few of them have mentioned about WFS T especially how WFS T can work on mobile phones Additionally geolocation
47. illustrated as shown in figure 13 including 1 Exporting data from OpenStreetMap 2 Converting and Importing data using FME Universal Translator 3 Manipulating and Optimizing data with pgAdmin III 4 Creating a data store in GeoServer For more details about the preparation steps see appendix C Data Preparation 29 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Export geographic features from OSM Use FME Universal Translator to convert data and import data into PostGIS FME 2 1 Convert data from XML format to PostGIS format Universal 2 2 Import the converted data into PostGIS Translator Use PostgreSQL pgAdminlll to manipulate and optimize data Use GeoServer Web Admin Page to create a workspace and a store pointing to data in PostGIS GeoServer 3 pgAdmin III Figure 13 Data preparation steps 30 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers CLIENT SIDE Since the goal of this project is to try out the capability of WFS T in combination with geolocation in order to edit geographic features through mobile browsers Therefore we must create a web based application that is able to 1 use to edit geographic features and 2 determine a user s location As mentioned in the investigation part to reach item 1 we will use OpenLayers while for item
48. in small cities or rural areas may contain more information such as bus routes walking tracks and flights of steps stairs on footways for instance in figurd11 the blue dotted lines in OpenStreetMap represent cycling routes that are separate from the road More examples of map features in OpenStreetMap are shown in figurd12 20 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Googie MAPS Bing Maps O enStreetMa amp E p wieiniivens p 3 4 CC Gjev 3 3 g a S g ji m P 2 El El M i 8 9 weg h a 9 cae a Gj vik e c 5 0 t je ps A 1psens5 93 Lu E an a d Xe s 3 a Ern g r 4 Lasse 8 Kurkeg e P geg G ZNE q 3 9 Kirkegata Liten A 8 2a y BY B Wu Vo a A t Ge s Gali 2 Biers a giernsons 9g ny ele E d gt e E Ys a ad F gt ig E j as E J E is S ye Kommuneoverleger d c E e 3 Giov o S amp le Se Sievik ee 3 5 i gt A g PA 3 P p gt A E S 9 P d 2 Figure 11 Map images from Google Maps Bing Maps and OpenStreetMap A WFS SERVER There are many well known platforms supporting the OGC Specifications available in the market today However the following products are concerned to be implemented MapServer Deegree GeoServer and ArcGIS server e MapServer is one of well known Open Source GIS server used for publishing data and creating web
49. ion Specification 7207 036 OpenGISGeography Markup Language GML Encoding Standard version 3 2 1 Grigsby J 2010 Mobile operating systems and browsers are headed in opposite direc tions http radar oreilly com 2010 05 mobile operating systems and b html Visited Jun 2010 Wikipedia org Mobile Browser http en wikipedia org wiki Mobile browser vi sited May 2010 Developer Android com Location Manager http developer android com reference android location LocationManager html visited May 2010 Steiniger S amp Bocher E 5 SEPTEMBER 2008 An overview on current free and open source desktop GIS developments Int J of Geographical Information Science F llman S Using WFS to build GIS support Master s thesis Department of computing science Ume University Sweden 2004 Vretanos P A ed May 2005 OpenGIS Implementation Specification 7704 094 Web Feature Service Implementation Specification version 1 1 0 Nanchang P R 22 24 MAY 2009 A WebGIS framework for vector geospatial data sharing based on open source projects The 2009 International Symposium on Web Information Systems and Applications 124 127 Jun J Chong jun Y Ying chao R amp Miao J 2008 The research and application of WFS based GML The International Archives of the Photogrammetry Remote Sensing and Spatial Information Sciences vol XXXVII Part B4 43 Using WFS T in combination with geolocation for online transa
50. is a new technology released for awhile and becomes helpful in GIS this days including in developing applications for mobile devices We can see that mobile phones have played important roles in our society which most people have their own mobile phones Not only we can use our mobile phones to talk or to send text messages to our friends but many modern mobile phones provide a service to access to the Internet So if we can make use of this kind of technology in combination with WFS T it will help to provide some useful information for those who are interested in using and or implementing WFS T in combination with geolocation on mobile devices and will probably be able to enhance functions and value of developing the applications in the near future Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 1 5 Research Questions Based upon the background and motivation and the problem definition the following research questions will be examined through the project RQ 1 Is it be possible to implement WFS T in combination with geolocation as a web appli cation used on mobile browsers RQ 2 What are the main challenges to make use of WFS T in combination with geolocation on mobile phones RQ 3 To what extent are map and geographic features can be displayed on mobile browsers 1 6 Methodology The idea of WFS T is not new but somehow it is still not widely used
51. l changeset 2418950 timestamp 2009 09 08T21 13 062 gt tag k amenity v post_box gt lt node gt lt way id 33652993 user Kagee uid 46430 visible true version l changeset 961477 timestamp 2009 04 25T22 57 032 gt lt nd refz 384977612 lt nd ref 384977619 gt lt tag k highway v unclassified gt lt way gt lt relation id 952454 user Kagee uid 46430 visible true version 1 changeset 4923930 timestamp 2010 06 06T23 20 492 gt member type way ref 35177205 role road gt member type way ref 61348664 role road tag k type v associatedStreet gt lt frelation gt lt osm gt Then we need to convert data into a format that can be loaded into PostGIS database In this step FME Universal Translator 38 can do the trick However in the paper Interface design for mobile devices mobile devices user interface which one of them is the size of a mobile device is usually small the author mentioned some concerned issues when designing so the developers of mobile applications have to cope with limited screen size Therefore as we plan to show geographic information on mobile devices which they may be not suitable for displaying large amounts of data we may also need to optimize our data too Furthermore a data store in GeoServer must be created in order to use it to connect to geographic data in PostGIS database To sum it up the processes of data preparation are
52. mapping applications It can be run on many major platforms such as Windows Linux and Mac OS X However MapServer supports only basic WFS read only that means we cannot use it to perform transation operation From MapServer official website WFS page it mentioned in To do Items and Known Limitations that GeoServer is recommended for those needing WFS T support 24 e Deegree is an Java API using for creating a GIS It is also an Open Source provided for free and conforms to many OGC Specifications including a transactional Web Feature Service WFS T For those new users who are interested in using Deegree there is plenty of tutorial available online However the limitation of performing WFS T by using Deegree is that it does not support transactions on shapefiles e GeoServer is designed for interoperability As same as Deegree GeoServer is an Open Source server written in Java and also offers full support for OGC standards including WFS T The main goal of GeoServer is to implement as a node within a free and open Spatial Data Infrastructure It intends to offer a free and open web server to publish geospatial data just as the Apache HTTP Server has offered a free and open web server to publish HTML With GeoServer WFS T enabled users can update delete and insert geographic data In short GeoServer is one of those tools users need to display maps on web pages and it is used in conjunction with clients such as uDig GVSig MapBuild
53. mation about the installation steps can be found in GeoServer User Manual provided in GeoServer org Additionally some required settings and problems during the setup are mentioned in appendix 27 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers e PostgreSQL has the current stable version as 8 4 4 released on May 17 2010 for Win dows OS By the way in this project PostgreSQL 8 3 4 is installed on the same machine as GIS server The installation process took few minutes like when we installed GeoServer Nevertheless only PostgreSQL alone cannot complete the requirement of being spatial database so we need to install PostGIS to add support for geographic objects to the Post greSQL and allows PostgreSQL to be used as a backend spatial database for geographic information system As a result PostGIS 1 5 is installed 2 Prepare data After we have GeoServer and PostgreSQL with PostGIS installed on the machine it is time to fill up the database In this project we decided to use geographic data from OpenStreet Map OSM project OSM allows us to feel free to download and use the full information for any purpose we like under an open source license 21 The following items are choices of geographic data formats that we are able to export from OSM 1 OpenStreetMap XML Data contains all the current raw geographic data in an XML format As a result we will get a fil
54. mlObject A WFS can be asked to retrieve element instances by traversing XLinks that refer to their XML IDs In this case the client should be able to specify whether nested XLinks embedded in returned element data should also be retrieved 5 Transaction This request is composed of operations that modify features including create update and delete operations on geographic features 6 LockFeature This feature ensures that serializable transactions are supported by processing a lock request on a feature while a transaction on that feature is being process 14 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Figure 7 illustrates a communication between a WFS server and a client which HTTP is used to handle requests as already mentioned above in details lt DescribeFeatureType gt lt LockFeature gt lt GetFeature gt lt Transaction gt lt Transaction gt Figure 7 Web Feature Server Communication Diagram 14 As of May 2010 there are two version of Web Feature Service WFS The first version 1 0 0 was adopted as an implementation specification by OGC on May 17 2002 And then the next version is 1 1 0 which was published on May 3 2005 As we already mentioned about the capa bilities of WFS in the previous pages table 2 shows the comparison of the operations between WFS 1 0 0 and WFS 1 1 0 Operations are the functions that can b
55. n 250 organizations from all around the world including govern ment private sector and academic organizations that have joined the OGC the followings are some examples of the OGC s members which are well known Google ESRI Microsoft ORACLE NASA IBM MIT and so on In the GIS world especially in the area of interoperable web mapping OGC web services are very meaningful because they provide the standardization and opportuni ties for users to share geospatial information even though data is from different sources and or different applications For instance refer to the earlier scenario in the previous chapter we move to a new house and want to search for nearby shops we are not required to understand the back ground processes of how we can get the returned data anyway what is going on can also be described based on figure 3 as followings 1 We launch a GIS application which created by using OpenLayers via a web browser 2 We submit a request asking for nearby shops 3 The request is sent to different servers 1 aserver that is responsible for providing map images as WMS is asked for a map image 2 a server that is responsible for providing geographic features as WFS is asked for information of nearby shops 4 Servers find relevant data and send responds back to the client application 1 a server that is responsible for providing map images as WMS sends a map layer 2 a server that is responsible for providing geographic fea
56. n limitation about supported platforms Figure 4 illustrates smartphone operating systems and their market shares 6 In 2006 users were mainly interested in using 5 operating systems including Symbian Windows Mobile RIM Linux and Palm OS respectively Symbian accounted more than 50 percent of the market and has been acting as a leader of mobile operating systems until the year of lately survey 2009 By the way we can obviously see that its market share has decreased while the market shares of RIM iPhone and Android have increased Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers significantly year by year In addition each mobile operating system supports different mobile browsers Table 1 shows default browsers used by major phone and PDA vendors We can see that many of them are proprietary software only Android Browser and Firefox for mobile are FOSS Free and Open Source Software Figure 4 Smartphone Operating System Market Share Percentage 6 10 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Z stopuaa yaq pue euoud pqow 1ofeur Aq pesn s19smo 1q INeJ9g T AQEL To 3uo pue Aejdsiq Nowy 19430 pue s3ru0 no9 4 DT Sunsures uo Arejatidoid pe1ueno IQON DVCYOW pry 09 1ue dor801 q9M p1ezn e910Y UI EIpeur n n A J
57. nLayers Strategy BBOX saveStrategyPoint 33 projection new OpenLayers Projection EPSG 4326 34 protocol new OpenLayers Protocol WFS 35 version 1 1 0 36 url geoserver wfs 37 featureType shop point 38 srsName EPSG 4326 39 featureNS http www hig no imt4901 osm 40 geometryName geom 41 42 Js 43 44 map addLayers osm shops 45 map addControl new OpenLayers Control LayerSwitcher 46 map zoomToExtent 47 new OpenLayers Bounds 48 12941319 173424 4110122 686702 18367287 606576 11544180 703298 49 transform map displayProjection map projection 50 51 52 57 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 53 54 function osm_getTileURL bounds 55 var res this map getResolutionO 56 var x Math round bounds left this maxExtent left res this tileSize w 57 var y Math round this maxExtent top bounds top res this tileSize h 58 var z this map getZoomO 59 var limit Math pow 2 z 60 61 if y lt 0 y gt limit 62 return OpenLayers Util getImagesLocation 404 png 63 else 64 x x limit limit limit 65 return this url z x y this type 66 d 67 68 lt script gt 69 lt head gt 70 lt body onload init TY lt div id map gt lt div gt 72 lt b
58. nal editing of geographic features through mobile browsers 3 Related Work At present we can see that there is a high competition in the software development market Many new tools have been released while some tools have been out of date Not only a proprietary or commercial software that always have new features patches for users to upgrade versions but also a free open source software that has been developed and released regarding users demands What is a free open source software and why it is interesting to be used According to the Free software Foundation www fsf org software can be labelled as free software if the associated license conditions fulfil the free software definition which grants four freedoms 1 The freedom to run the program for any purpose 2 The freedom to study how the program works and adapt it to your needs 3 The freedom to redistribute copies so you can help your neighbor 4 The freedom to improve the program and to release your improvements to the public so that the whole community benefits From the definitions above we come up to the opposite of free software which is proprietary software While free software respects the users freedoms the proprietary software identifies ow nership The main benefit of using free software is that it can help users to save their budgets In the GIS world there has been rapid growth in the number of open source GIS applications which they can be class
59. nalyzed and the conclusion is made Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 2 Background 2 1 OGC Web Services In recent years there has been an explosion of web mapping applications which allows users to access to huge amounts of geographic data via their web browser The operations to perform the processes online are called Web Service Since the area of this kind of implementation seems big and there are many providers who have developed and provided web mapping applications in the market to make one product datum to be used with the others the implementation has been developed by following the OpenGISO Standards OpenGIS is a Registered Trademark of the Open Geospatial consortium Inc OGC OGC has defined interfaces and protocols for supporting online interoperable solutions which its goal is to develop standards that enable interoperability of spatial information and services Recently the OGC standards baseline comprises 30 standards such as Web Map Service WMS Web Feature service WFS Geography Markup Language Lan guage GML Keyhole Markup Language KML and so on Figure SEWilco describes how OGC standards help GIS tools to communicate by using geoservices server with interfaces and appli cations sketch 4 green represents read and write paths while dotted arrowed line indicates mostly read only data flow Currently there are more tha
60. ng nearby places are displayed on a map as shown in figure 17 a yellow smile icon represents her location while green circles are nearby shops Addtionally fi gure 18 describes a sequence of operations that the application provides for online transactional editing of geographic features through mobile browsers which the use case contains all possible states since the application is launched until a user quits the application Furthermore refer to the earlier example in the Introduction chapter we move to a new house and want to search for nearby shops in this case this application can be helpful as we are going to discuss in greater details in the next paragraph A scenario for the system Jasmin is an international student from China coming to Norway to study a master s degree in Media Technology at Gj vik University College GUC in Gj vik Today is the first day that she reaches Gj vik She meets Li Xiatao who is a second year student studying the same major as her he comes to pick her up at the train station and drives her to Kallerud where she is going to stay Kallerud is a student village located 500 meters from GUC and 2 km from Gjovik city center with laundry and internet access are provided Once Jasmin arrives at her room in Kallerud she finds that she needs to buy many stuff including food and some convenience products She asks Xiatao whether there are any supermarkets around the campus Instead of answering her question Xiat
61. nk wfs transactionsummar wfs totalinserted totalinserted gt totalupdated totalupdated gt 0 s totaldeleted gt l lt totaldeleted gt wfs transactionsummary ult lt wisitransactionresults gt lt wf ransactionr lt wfs insertresults wis feature gt featureid gt ogc featureid fid none gt lt wfs feature wfs insertresults wfs transactionresponse 10 The user can save the transaction by selecting a save button The below code shows a background response when the user moves a point on the map and selects the save button sion 1 1 0 xsi schemaLocation http www opengis net wfs http copernicus hig no 8080 geoserver schemas wfs 1 l 0 wfs xsd http f fwww opengis net ogc xmlns osm http www hig no imt4901 osm xmlns tiger http www census qov xmlns wfs http www opengis net wfs xmlns http www openplans orq topp xmlns i http www w3 org 2001 XMLSchema instance xmlns sf http www openplans org spearfish xnmlns ows http www opengis net ows xmlns qml http link http www w3 org 1999 xlink wfs transactionresponse v xmlns fwww opengis net qml xmln wfs transactionsummar totalinser totalinserted totalupdated gt 1 lt totalupdated lt wfs totaldeleted gt 0 lt wfs totaldeleted gt lt wis transactionsummary fwis transactionresults gt wfs tra
62. nsactional Web Fea ture Service is a part of WFS With WFS T users can perform transactional operations such as create update and delete geographic features Geographic features can be described as a set of properties which may include a name type and value For example one country can be defi ned as a geographic feature containing the following properties country name country capital country lonlat country population each property can have different type and value such as country name has a type as string and has a value as Norway while country population has a type as number and has a value as 4882600 In this implementation GeoServer is selected to be used as GIS server software PostgreSQL with PostGIS is used as datastore and OpenLayers is used in creating web based geographic application Additionally W3C Geolocation API is used to detect users locations from using their devices in this case an Android phone is used as a test device during the implementation Once users launch their mobile browsers to connect to the Internet The application will figure the users locations and show the position as a point on a map through their mobile browsers Moreover the amenity places around their area will be displayed The prototype allows users to make online transactions such as insert a new point as a new place When users finish and save their work all data will be recorded in the database via WFS T operations The project report will
63. nsactionresponse gt 68 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 12 The user is able to choose whether she wants to see her location Current Position and or nearby shops Shops on the map O OpenStreetMap Overlays Shops M Current Position O OpenStreetMap Overlays Shops W Current Position Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 13 The user can select on any of geographic features green dots to see its description Once the user does so a pop up message will appear with the geographic description n Ese E So Sentrum B Va ts y y We a es T EI 14 The user can pan and or zoom the map by selecting the buttons on the top left For the below case the user zooms in the map as a result she can see the map in more details A 42 44 Ee npe Ld T e E Gone m Aw es Totens Sparebank 70
64. nsactionresults wfs insertresults wfs feature featureid fid none gt lt lt wfs feature gt wfs insertresults x wfs transactionresponse 67 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 11 The user can save the transactions by selecting a save button The below code shows a background response when the user adds 3 new points deletes 1 point and moves 1 point on the map and then selects the save button wfs transactionresponse version 1 1 0 xsi schemaLocation http www opengis net wfs http copernicus hig no 8080 geoserver schemas wfs l 1 0 wfs xsd xmlns http www opengis net ogc sm http www hig no imt4901 osm r http fu census gov xmln http www opengis net wfs xmlns t www openplans org topp xmlr http www w3 org 2001 XMLSchema instance spearfish xmlns ows http wow opengis net ows xmlns qml http fwwwe opengis net gml xmlr xlink http www w3 org 1999 xlink lt wis totaldeleted gt 1 lt w lt wis itransactionsummary gt lt wfis transactionresults gt lt wfs transactionresults gt ogc featureid fid shop point 18 gt lt oge featureid gt wfs feature fid shop point 19 ogc featureid lt w s feature gt lt wfs feature gt ogc featureid fid shop_point 20 gt lt wfs feature wfs insertresults lt wis itra
65. ody gt 73 lt html gt The steps of how the above code works can be explained as in the following terms 40 1 Load the OpenLayers library 4 lt script src http openlayers org api OpenLayers js gt lt script gt The http openlayers org api OpenLayers js URL points to the location of a JavaScript file that loads OpenLayers This file helps us to put a dynamic map in our web page with no server side dependencies The file OpenLayers js can also be stored on our machine Anyway to always use the latest of the script we may want to point a location of the file to the link as we mentioned in the example above We can use debugging tools such as Firebug in Firefox to explore the OpenLayers library from our browser 2 Define a container for a map Thi lt div id map gt lt div gt This is a container for the map that we create in our page markup Later when we initialize the map object we will give the id of this div element to the map s constructor 3 Set a display projection and create a map 12 var options 13 projection new OpenLayers Projection EPSG 900913 14 displayProjection new OpenLayers Projection EPSG 4326 15 units m 16 maxResolution 156543 0339 17 maxExtent new OpenLayers Bounds 20037508 34 20037508 34 18 20037508 34 20037508 34 19 Fs 20 21 map new OpenLayers Map map options OpenLayers allows us to set a display projection to prevent us confusion
66. ol and allow us to develop web a mapping application Anyway OpenLayers is selected over OpenScales to be used for the implementation of the web application since OpenLayers seems to be far developed with good documentation and examples available on its website Since we want to test whether WFS T can be used in combination with geolocation through mobile browsers to use OpenLayers alone seems not enough in this case we need a solution that can help to provide a user location and show it on a browser Actually the concept of locating users by making use of the geographical position of their mobile devices is not new as there are many location based mobile applications available in the market today such as Google Latitude a location aware mobile application created by Google Gowalla a mobile web application created by Alamofire allowing users to check in to locations that they visit using their mobile devices and Foursquare a web and mobile application offering users to connect with friends and update their location However at the time of doing this project there are still few solutions that can be used to implement a mobile web application in order to detect users locations when they launch an application through their mobile browsers the following APIs are concerned as candidates to be implemented in the project e Google AJAX APIs 35 developed by Google includes a simple object property called 25 Using WFS T in combination wit
67. on with geolocation for online transactional editing of geographic features through mobile browsers A GeoServer Issues After we install GeoServer the below process may be required to implement We will NEED to set the JAVA HOME environment variable if it is not already set This is the path to your JDK JRE such that JAVA_HOMED0 bin java exe exists We may also need to set the GEOSERVER HOME variable 20 which is the directory where GeoServer is installed and the GEOSERVER DATA DIR variable which is the location of the GeoServer data directory usually 99GEOSERVER HOMFEMdata dir The latter is mandatory if you wish to use a data directory other than the one built in to GeoServer The procedure for setting these variables is identical as shown in table 5 and table 1 Navigate to Control Panel gt System gt Advanced gt Environment Variables 2 Under System variables click New 3 For Variable name enter JAVA_HOME For Variable value enter the path to your JDK JRE 4 Click OK three times Table 5 Setting environment variables 47 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Edit System Variable Variable name JAVA HOME Variable value C Program Files Javaljdk1 6 0 14 j Cancel Figure 19 Setting JAVA HOME Edit System Variable Variable name GEOSERVER_DATA_DIR Variable value
68. op_point Z gt Gj vik Sentrum lt qml name gt name gt Rema 1000 id gt 4 944 opening hours Mo Fr 07 00 22 00 Sa addrhousenumber gt 1 A lt osm addrhousenumber gt osm id gt 08 0 21 00 lt osm opening hours 64 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 5 The user is able to add a new shop by selecting a pencil with a plus sign button and then locate the new shop on the map i v A E A v 8 q 6 The user is able to delete green dots by selecting a pencil with a minus sign button and then select the point to delete 65 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 7 The user is able to move green dots by selecting a move button and then select the point to move 8 The user can save the transaction by selecting a save button The below code shows a background response when the user adds a new point on the map and selects the save button wfs transactionresponse version 1 1 0 xsi schemaLocation http www opengis net wfs http copernicus hig no 8080 geoserver schemas wfs l 1 0 wfs xsd xmlns ogc http www opengis net ogc xmlns osm http www hig no imt4901 osm xmlns tiger http f f wow census gov xmlns wfs http www opengis net wfs xmlns topp http www openplans org ftopp xmlns xsi h
69. ormation about the speci fication and scenarios were presented She also raised some important issues about how access control handled in the OGC WFS Implementation Specification and how appropriate security levels could be implemented which at that time they were not mentioned in the specification As the goal of her project is to investigate the technique of using WFS she developed some demo systems and ended up with a result from implementing demo system level 2 as shown below in figure 8 The system comprises of a client application created by using Java a WMS server MapServer a WFS server Deegree and a spatial database PostGIS Users can use the client application to request for geographic information which the tool is able to access to both the WMS server and the WFS server Client Java Virtual WMS server has MapServer f m OS Windows PostGIS Virtual machine XP OS FreeBSD Command and Control applications Chent interactive Java application WFS server VM Client Deegree WMS clen E HTML Virtua le ple client machine Niap serve web browser OS Windows XP Figure 8 Demo System level 2 Using WFS to build GIS support by Sandra F llman 10 Knut Seelid researched the techniques of using WFS T on mobile phones in his master s thesis WES T and mobile clients 18 His work proves that WFS can be used in a system to generate map images and geographic features moreover the r
70. ow your location Learn More Share Location Don t Share _ Remember for this site ES OpenStreetMap Figure 29 If a browser supports Geolocation we will be asked whether we want to share our location information 61 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers The page at http copernicus hig no 8080 says A Your geographic coordinates latitude 60 787223 longitude 10 686921 Figure 30 If a browser supports Geolocation and we allow it to gather our location information we will get a pop up window showing our position Message from webpage A Your browser does not support Geolocation API Figure 31 A pop up window shows that our browser does not support geolocation 62 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers F A client application Some screenshots of a client application are revealed as shown below The application can be accessed at http copernicus hig no 8080 geoserver www loc imt4901 html 1 When a user launches an application if a browser supports Geolocation she will be asked whether she wants to share a location e copernicus hig no wants to know your location Learn More C Remember for this site ES 2 If the user accept the request there will be a pop up massage informing her position as shown earlier in figur
71. regarding map coordi nates In this case transformation is made from the map projection EPSG 900913 to the display projection EPSG 4326 Moreover the coordinates that we use in setCenter are not longitude and latitude but they are in projected units meters The maxResolution of the map defaults to fitting this extent into 256 pixels resulting in a maxResolution of 156543 0339 And for the maxExtent parameter the coordinates strech from 20037508 34 to 20037508 34 in each direction At line 21 we can see that there are a lot of maps in the statement The first declares the variable to give it a short name that can be used elsewhere in the Javascript code Since the variable is declared outside the function that initializes it it can be used globally which helps 58 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers for debugging The second OpenLayers Map called an object tells the OpenLayers Javascript that we are using the Map class which means that all of the built in parameters and options can be accessed The third is the name or identifier of the div that we are putting the map in so OpenLayers knows where to draw the map on the page So this section basically creates a new OpenLayers Map object and gives it the variable name map 4 Create Layers 22 var osm new OpenLayers Layer TMS 23 OpenStreetMap Mapnik 24 http tile openstreetmap
72. s Table 4 Comparison of GIS products to be used as a WFS server DATASTORES GeoServer reads a variety of data formats such as PostGIS MySQL Oracle Spatial ArcSDE Shapefiles and so forth To make a decision about which datastore we should use in this project the choice stands between PostgreSQL with PostGIS MySQL and Oracle Spatial e PostgreSQL with PostGIS 29 PostgreSQL has been developed for more than 15 years as open source object relational database system It can be used on all major OS such as UNIX Mac OS X and Windows Moreover there are many interfaces supporting Java ODBC Perl Python Ruby C C PHP and so on However only PostgreSQL alone is unable to work with spatial data we need to install PostGIS which is an extension adding support for geographic objects to the PostgreSQL object relational database e MySQL BO has been released since 1995 as an open source relational database management 23 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers system Many well known software projects such as WordPress Wikipedia Google and so forth use MySQL regarding it offers nice features and is flexible to be used as it provides source code available under the terms of the GNU General Public License MySQL is written in C C and can be used on cross platform e Oracle Spatial is commercial software offering data management for geographic
73. s but we are also able to use some tools on thin clients such as personal computers and mobile devices As mobile devices have been involved in human communication we can see that many people have their own mobile phones and use their devices not only to make or receive a phone call but also do somethings else The modern mobile phones support many services such as MMS MP3 camera GPS Internet and so forth At the present of time many GIS applications developed for mobile phones have used GPS receivers of mobile phones to locate locations of users and displayed nearby attractions and facilities Anyhow not only GPS that can be used to provide user s position but also location inferred from network signals such as IP address MAC address WiFi connection and so on And as mentioned above about using Google Maps if our mobile phones have GPS function and or can be used to access to the Internet no matter where we are we will probably never get lost imagine how easy our lives will be from making use of this kind of technology 1 1 Topic covered by the Thesis The purpose of the master s thesis is to review and try out the capabilities and features of Tran sactional Web Feature Service WFS T in combination with geolocation in editing geographic features through mobile browsers based on one of those OGC standards called Web Feature Ser vice WFS With WFS T users can do transactional operations such as create update and delete geographic
74. s Android phone copernicus hig no wants to know your location Learn More Share Location Dont Share C Remember For this site E AZ C Figure 16 Jasmin is asked to share a location when running the application via Firefox on a PC 33 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Figure 17 A yellow smiley icon locates Jasmin s location green points represent nearby shops 34 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers to from Client launches the web application Web server through mobile browser Application shows Map and geographic WMS WFS features servers is asked to share a location geolocation 1 If answer Yes continue the process 2 If answer No stop the process Application identifies client s location geolocation based on availability of cell tower and or WiFi access points 5 3 NET 5 5 6 Application shows a client s location on geolocation the map un o updates features WFS server deletes features WFS server exits application Figure 18 An application Use Case 35 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 5 Results and conclusion 5 1 Results In this project we have developed a pro
75. si schemaLocation http www opengis net ogc http schemas opengis net wufs 1 0 0 0GC exception xsd ServiceException http www hig no imt4901 project tourism point is read only x ServiceException z ServiceExceptionReport Figure 24 An error occurs when adding a new point in a table with no PK available in the table 54 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers C 4 Create Workspace and Store in GeoServer To use PostGIS with GeoServer first we will probably want to create Workspace which is a container used to group similar layers together And then a new data source can bee added by choosing PostGIS NG PostGIS database as a Vector Data Source Figure 25 and shows screenshots of adding new workspace and data store Additionally the document of how to create a new workspace and a store in details can be found in New Workspace Configure a new workspace Name wtst2 Namespace URI nttp Jjwwewhig no imt4801 project The namespace uri associated with this workspace Default workspace O Submit Cancel Figure 25 Configure a workspace New data source Choose the type of data source you wish to configure Vector Data Sources G Directory of spatial files Takes a directory of spatial data files and exposes it as a data store 3 PostGIS PostGIS Database G PostGIS INDI PostGIS Database INDI
76. son of WFS Servers We can see that MapServer Deegree and GeoServer are Open Source software while only ArcGIS Server is commercial software Though ArcGIS Server is now using by the Geomatics group at faculty of technology economy and management at Gj vik University College where we study using it seems limit for those new users who interested in learning GIS due to it costs money to use So we would prefer to use free software By the way even though MapServer is one of Open Source applications which has been developed for quite some years it does not support WFS T So now the choice stands between Deegree and GeoServer Both of them have transactional capabilities and seems considerably widely used among GIS developers However we decided to use GeoServer as a WFS server The main reason is because the author has some experiences in implementing it so under the time limit in developing the prototype it would be better to use something that we are familiar with Moreover GeoServer is a fully functional open source WFS T server that follows the OGC standards for geographic information sharing with good tutorial and demos available in its official website So as a result GeoServer is selected to implement as a WES server in this project Software Language OpenSource WFS WFS T MapServer C Yes Yes No Deegree Java Yes Yes Yes but transactions on shapefiles do not work GeoServer Java Yes Yes Yes ArcGIS Server Net Java No Yes Ye
77. te a user s position by creating a location aware web page to make a user share her location from using her mobile device which in this case we use Geolocation API Generally the sources of location information can be Global Positioning System GPS and location collected from network signals containing IP address WiFi MAC addresses and so forth The following code is an example of how to get a basic location information 37 31 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers Example of a one shot position request navigator geolocation getCurrentPosition showMap 4 2 2 Testing After a prototype is created we have tested it both on mobile browsers and web browsers on personal computers which some screenshots of the application are captured and revealed For instance figure 15 shows that when a user runs the application through a mobile browser she is asked whether she allows the application to gather her location information While figure 16 and 17 happen when a user launches the application through Firefox which similar to the pre vious case that the user runs the application on the mobile browser she is asked whether she wants to share her location information the application will do so in case that she agrees And once she clicks a Share location button to allow the application to determine where she is as a result her location includi
78. the earth I Figure 1 is the map drawn on birch bark presenting the migration legend of the native American called Ojibwe around 1820 It illustrates the lives of Ojibwe origins since they were born until moved to the new places which the spiritual realities had taken part Moreover it also flashes the essential of making maps related to their lives and thoughts as the symbols of significant spiritual guides were used along the route from the right to the left St Louis River Mississippi River Red Lake Lake Superior Lakes Erie Huron amp Ontario Figure 1 The Native map shows the migration legend of the Ojibwe ca 1820 As time goes by from drawing pictures on the rock in the past until now using maps on digital devices the changes of technology have been taking part of how we understand the world including the ways to create maps GIS Geographic Information System or Geographical Information System is the combination of cartography maps and database technology which we may be familiar with and use it in our daily lives but many of us do not realize about it As the Internet today has played an important role providing us huge information we probably find all information we want over the Web including spatial information Spatial Information informs the physical location of objects and the relationship between objects For simple example when we are online and want to find directions from one place to t
79. totype to see whether we can make use of WFS T in com bination with geolocation to perform online transactional editing of geographic features through mobile browsers As a result we can describe as answers to the research questions as followings RQ 1 Is it possible to implement WFS T in combination with geolocation as a web based application used on mobile browsers From developing and performing a test we found that WFS T and geolocation can work well together through a mobile browser on Android phone However because W3C Geolocation API that we selected to use instead of using other geolocation APIs such as Google Loader and Gears is still new not all browsers support it As a result our applicant can work completely only on those browsers that support W3C Geolocation API We have tried on various browsers both on PCs and mobile phones results are listed below NORMAL BROWSERS e Mozilla Firefox version 3 5 and later Once we open the application we will be asked for permission to share our location similar to figure as shown earlier in the previous chapter In case that we agree Firefox will gather information about nearby wireless access points and our IP address Then it will send the information to the default geolocation service provider which is Google Location Services to get an estimate of our location Finally the estimated location is shown on the application as a yellow smile marker 17 e Google Chrome version 5
80. ttp www w3 org 2001 XMLSchema instance xmlns sf http www openplans org spearfish xmlns ows http www opengis net ows xmlns qml http ww opengis net qgml xmlns xlink http www w3 o0rg 1999 xlink lt wfis transactionsummary gt lt wfs totalinserted gt 1 lt wfs totalinserted gt lt wfs totalupdated gt 0 lt wfs totalupdated gt lt wfs totaldeleted gt 0 lt wfs totaldeleted gt lt wfs transactionsummary gt wfs transactionresults lt wfs transactionresults gt wfs insertresults wfs feature lt ogc featureid fid shop point 11 gt lt ogc featureid gt wfs feature wfs insertresults wfs transactionresponse 66 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 9 The user can save the transaction by selecting a save button The below code shows a background response when the user deletes a point on the map and selects the save button xsi schemaLocation http www opengis net wfs xmlns c http r http lt wfs transactionresponse version 1 1 0 http copernicus hig no 8080 geoserver schemas wfs 1 1 0 wfs xsd www opengis net ogc xmlns osm http www hig no imt4901 osm www census qov xmlns wfs http www opengis net wfs xmlns t topp xmlns i http www w3 org 2001 XMLSchema instance fspearfish xmlns ows http www opengis net ows xmlns gml www opengis net qml xmln link http www w3 org 1999 xli
81. tures as WFS sends a GML file 5 The application processes the returned results Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers OpenLayers Javascript maps Web server Google server World Vind Google Earth WCS coverages Shapefiles Figure 3 An example of how OGC standards help GIS tools communicate by SEWilco 4 Using WFS T in combination with geolocation for online transactional editing of geographic features through mobile browsers 1 displays a map image from WMS 2 validates GML and draws vectors in this case nearby shops are presented as points 6 The map and the nearby shops are displayed We can see that the OGC web services in this example WMS and WES help to solve the pro blem of the lack of interoperability With the use of open standards we are able to manipulate spatial information no matter how we get it or where it is from 2 1 1 WMS OpenGIS Web Map Service WMS Implementation Specification is one of the most well known Implementation Specifications by OGC It offers a simple HTTP interface for map images from distributed geospatial databases Once a client send a request by specifying the area of interest to the server the service produces a content containing geographic information within the area that the client requests and then send the response back to the client as map images
82. us feature of WFS T is that it allows users to insert update and delete geographic data From the project implementation we found that it is possible to implement WFS T in com bination with geolocation as a web based application to be used on mobile browsers However there are some difficulties and limitations in using the application including an access to the Inter net is required during the usage of the application an error from selecting wrong geographic features can easily occur especially when the features are close to each other and zooming and panning the map are not easy to perform due to the similar reason as selecting geographic features which is buttons are close to each other Futhermore the application is unable to work on those browsers that do not support geolo cation due to W3C Geolocation APT is still new Geolocation is a process of tracking and mapping which can be performed by connecting a geographic location with IP address or device GPS co ordinates To bundle W3C Geolocation API in the application will make the web browser can determine where we are located In this case we may curious about our privacy For those web browsers that support W3C Geolocation API such as Firefox and Google Chrome have a policy not to share our location without our permission We can see that when we visit a page that geolocation code is bundled we will be asked before any information is shared By the way since Internet scams and frauds hav
83. vascript based web application which allows us to show geographic data on our web pages To use it we are not required to have much knowledge in javascript but we need to respect the code and the order in which the components are declared and used The following code is an example of how to use OpenLayers to show map data and geographic features in this project 1 lt html gt 2 lt head gt 3 lt title gt OpenLayers lt title gt 4 lt script src http openlayers org api OpenLayers js gt lt script gt 5 lt script type text javascript gt 6 var lon 5 7 var lat 40 8 var zoom 5 9 var map select 10 11 function init 12 var options 13 projection new OpenLayers Projection EPSG 900913 14 displayProjection new OpenLayers Projection EPSG 4326 15 units m 16 maxResolution 156543 0339 Ig maxExtent new OpenLayers Bounds 20037508 34 20037508 34 18 20037508 34 20037508 34 19 20 21 map new OpenLayers Map map options 22 var osm new OpenLayers Layer TMS 28 OpenStreetMap Mapnik 24 http tile openstreetmap org 1 25 type png getURL osm getTileURL 26 displayOutsideMaxExtent true 275 attribution lt a href http www openstreetmap org gt OpenStreetMap lt a gt 28 29 234 30 var saveStrategyPoint new OpenLayers Strategy Save 31 var shops new OpenLayers Layer Vector Shops 32 strategies new Ope
84. wfs service WFS amp version l l amp request DescribeFeatureType amp typeName osm 3 shop point http www opengis net wfs http copernicus hig no 8080 geoserver schemas fwfs l l O0 wfs xsd xmlns ogc http www opengis net ogc xmlns osm http www hig no imt4901 osm xmlns tige http www census gov xmlns wfs http wwwu opengis net wfs xmlns topp http www openplans org topp xmlns xsi http www w3 org 2001 XMLSchema instance xmlns http fwos openplans org spearfish xmlns ows http www opengis net ows xmlns gml http www opengis net gml xmlns xlink http www w3 org 1999 xlink aqunl featuremembers gt osm shop point gnl id shop point l qml name Kiwi Strandgata lt qml name gt lt osm id gt 4 88515702E8 lt osm id gt lt osm opening hours gt Mo Fr 07 00 23 00 Sa 07 00 21 00 lt osm opening_hours gt osm user StianEllingsen lt osm user gt lt osm shop supermarket lt osm shop gt osm timestamp 2009 09 12T21 12 osm timestamp osm visible true lt osm visible gt 60 lt osm phone gt osm phone 47 611 lt osm name gt Kiwi Strandgata lt osm name gt lt 0sm geom gt gnl multipoint srsName http www opengis net qgml srs epsq xmlf4326 lt gml pointmember gt lt gml point gt gm pos gt 10 6948648 60 7935921 lt gml pos gt fgml point gt qgml pointmember qnl multipoint osm geom gt sm shop point osm shop point gml id sh
85. while geolocation API is new and seems quite useful in the development of GIS applications especially for mobile phones In this project we are interested to implement something related to WFS T and can work on mobile browsers Not only the literature study is made but also the prototype is developed The literature study provides us some useful information about WFS T and relevant issues in which we can adapt it with our system such as in planning and developing steps To make it more understandable the methods we use to implement this project can be pre sented based on research questions as described below RQ 1 Is it be possible to implement WFS T in combination with geolocation as a web applica tion used on mobile browsers To answer this question both literature study and the prototype are made Researching avai lable technology and related papers give us the clear picture of how WFS T and geolocation works including the requirements we need and also the issues we should concern in implemen ting them In this case for example Web Feature Service Implementation Specification is revie wed and as a result we get some requirements and also supported operations of WFS which are discussed later in Related Work This steps provide us significant background and lead to develop an implementation plan And then we can create a prototype based on the plan and once we perform a test the answer to this question is revealed RQ 2 What ar

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