Open Source GIS Architecture Testing at EPC

Nomeneta Saili

Pacific GIS/RS Conference, Fiji, 2011

Overview

• Backdrop• Open Source GIS Architecture• Architecture Diagram • Database (PostGIS/PostGres)• Application Server (GeoServer)• Cache (WebCache)• Desktop GIS Client (QGIS)• Web Client (Openlayers/GeoEXT)• Further Open Source Developments/Testing

Backdrop

EPC GIS use is increasing rapidly in application and number of users. The result is the growth in GIS data generation/maintenance at EPC with the following issues/opportunities that needed to be addressed

• Data management issue (Overall main issue)• Field use of GIS data• License cost for growing number of GIS users• Need to modify attribute data from client end

Open Source GIS Architecture

• Test for solution to issues brought about by the growth in GIS at EPC

• Centralize spatial database, web server, web cache, desktop GIS client still in testing phase

• Web client still in development • Open Data Kit in pre testing phase

Architecture Diagram

Web Client(Openlayers +GeoEXT)

Desktop Client(QGIS 1.7)

Application Server

(GeoServer)

Cache (WebCache)

Database(PostGIS)

EPC Network

Field Data Collector

(ODK) (Pre-testing

Phase)

GPRS

Database

PostGIS 1.5 + Postgres 8.4• Spatial Database (Spatial Index)• Centralize. One main copy of EPC GIS data to

minimize data fragmentation from the development of departmental GIS in various EPC Division due to rapid increase in use of GIS at EPC

• Support WMS,WFS,WFS-T

PostGIS/Postgress Screen Shot

phpPgAdmin Interface of EPC Power User GIS Postgres Database

Application Server

Geoserver 2.0.2• Serves/edits maps/data using WMS, WFS,

WFS-T • Use PowerUserGIS database

(PostGIS/Postgres)• Many map styling features for stylized web

maps

Geoserver Screen Shots

Geoserver Admin Web Interface

Layer group interfaced with EPC Vehicle Tracker to use for Power Switching Application

Geoserver Map Example

Cache

WebCache • Bundle with Geoserver in version 2.1.2• Caches both vector and raster data• Tiling and Pyramids • Improve request response time

Desktop GIS Client

QGIS 1.7 (wroclaw)• For Heavy GIS Users that require advance GIS

functionality• Opens most GIS file format from a service, database or

local GIS Data repository • Access to both Geoserver and PostGIS• Enables client editing of attribute and geometric features• Versioning system • Offline packaging and synchronization of GIS data for

field work

Access to GeoServer and PostGIS

Geoserver

PostGIS

QGIS Versioning

Allows for creation of version layers on PostGIS as well as their management. Show differences, show changes logs and committing or reverting changes made by users. Extremely important for management of client edits of PostGIS database

Offline editing

• Offline/Field use of EPC GIS rapidly increasing • Current WebGIS (Intergraph Geomedia Web

Map) data is only accessible when client is connected to EPC LAN.

• Currently use MapInfo for offline with local copy of GIS database on each client machine. Huge issue with data management with different users with different copy/edits of GIS database.

QGIS Offline Editing

• Allows users to package Central PostGIS tables when connected to PostGIS database.

• Allows offline editing of PostGIS tables when not connected

• Allows synchronization of user edits to the Central PostGIS database when connected back to PostGIS database

Convert/package project to offline

Once client connected, synchronize with PostGIS

Web Client

Openlayers + GeoEXT• For General GIS users that require minimum GIS

functionalities.• Java script and EXT JS based• Enables client editing of attribute and geometric

features• Access to both GeoServer and PostGIS.

Currenlty set to access GeoServer only• Still in development

Web Client Screen Shot

In Development

Further Open Source Developments/Testing

• QGIS Web Server – Alternative to GeoServerAllows publishing of QGIS interface as a web client. Easier than coding the web interface with Openlayers + GeoEXT for advance function

• Geoserver Versioning System. • Open Data Kit (ODK) – Android based field collection

techAllows any android device to be used as a data collection device with digital forms sent via GPRS to back end postgres database

ODK Continue

• Allows users to define their own data collection forms which includes GPS Capture provided android device has GPS capability

• Sends data to backend database for access in various formats

• Intended as a cost effective field asset reporting tool to be use by any general EPC field staff to report on any general field survey not requiring EPC GIS Trimble field asset capture equipment/software to reduce increasing load on EPC GIS unit field survey services

Thank you/Faafetai