Putting the Pieces together: Combining Open Source Components to create a WebGIS.

Transcription

1 Putting the Pieces together: Combining Open Source Components to create a WebGIS. Shriram Ilavajhala University of Maryland College Park, MD. USA.

2 Today s Topics A quick background on our project Our legacy WebGIS and issues with it Our work toward developing an open source WebGIS system Discussion

3 A quick background We are working on developing a WebGIS to display/query/download NASA-supplied hotspot (fire) data

4 A quick background Project named FIRMS - Fire Information for Resource Management System

5 A quick background Funded by NASA

6 A quick background Ultimate goal is to transition FIRMS to operational partners with a global monitoring mandate UN FAO, Conservation International, UNEP

7 Objective of FIRMS Provide users with fire and related information rapidly in easy-to-use formats and methods

8 FIRMS Product Development Based on: Multiple products and services to deliver fire data rapidly to users Multiple data formats, based on openstandards Easy-to-use, intuitive interfaces/systems Open Source Components, Software, and Protocols

9 So, what s the BIG deal? Lots of data: Constantly growing database size, with10,000+ points per added every single day

10 So, what s the BIG deal? Querying the archive: Data archive dating back to Do the math 10,000+ points per day for the past 7 years. That s hmm a lot of points!

11 So, what s the BIG deal? High traffic volume: Users from all over the globe, representing 75+ countries

12 Our requirements Fast and efficient fire archive querying, data display and download. A robust mapping engine A flexible toolkit to develop a GUI (frontend) A rock-solid, scalable database A system that is built with open standards, without cost/licensing limitations.

13 A quick look at our legacy system We have a legacy system that runs on a Windows server. Called Web Fire Mapper The spatial/database software components are commercial vendor-based (ESRI ArcIMS / ArcSDE, MS SQL Server, etc)

14 Issues with our legacy system Slow response of ArcIMS when fire archive is queried Frequent Crashes of ArcIMS/ArcSDE Incremental costs and licensing fees for software: Microsoft Windows (server version) ArcIMS /ArcSDE Microsoft SQL server Cost/Licensing issues involved in distributing the product to our partners

15 The Solution To try the alternatives Free and Open Source Software! We are currently developing a new version of FIRMS Web Fire Mapper with 100% open source components.

16 Suitability of Open Source Software for our project Fulfills our requirements Lets us develop high-performance, custom applications that suit our needs Each component can be tailor-made to suit our needs Virtually removes all issues with licensing restrictions Almost zero-cost software distribution

17 Open Source Components Used Here are the major pieces : Google Web Tool Kit (WKT): Front-end Minnesota MapServer: Mapping Engine PostgreSQL/PostGIS: Spatial Database Fedora Linux (Core 5): O/S

18 Let us take a very brief look at each of these components...

19 User Interface Google Web Toolkit (GWT) GWT wraps around the MapServer CGI and PostgreSQL/PostGIS Hides the internal functionality of the spatial database and the mapping engine by providing a neat AJAXy interface Easy to code Java classes that compile to JavaScript/HTML/XML

20 Mapping Engine Minnesota MapServer The Map Server CGI provided the powerful and stable mapping functionality we were looking for Enabled us to present custom queries to enable faster data access

21 Spatial Database PostgreSQL/PostGIS: Provided us with a robust and scalable solution to our ever-increasing dataset size. PostGIS enabled the spatial query of data stored in PostgreSQL Enabled faster data access with custom designed tables to handle large queries Provided us with an enterprise-quality data storage and retrieval.

22 Features of the new system...

23 Features of the new system Raster Tiling We ve developed a simple tiling mechanism for all the rasters Once created, a raster tile can be used over and over for repeated queries, resulting in faster display speeds Rasters around the view port are pre-fetched to enable smooth dragging and panning of the map.

24 Ability to querying the entire archive The new system is capable of querying the entire fire archive. Aggregate tables prevent entire database search and display a block display

25 Features of the new system Standard GIS tools Zoom/Query/Identify functionality developed using custom programming Additional display controls to provide users with full control of hotspot display (based on a satellite, time period, etc) AJAX-based Interface Quick and responsive. Easy to develop using GWT s Java classes

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28 Current Status of the project...

29 Undergoing internal (alpha) testing

30 Beta 1.0 Will go LIVE in December (hopefully!)

31 What else can be done with this system??

32 Can extend this system to support non-browser GIS platforms, like Google Earth and NASA Worldwind

33 How?

34 Extending the system to support non-browser platforms Java-based servlets can be programmed to support Google Earth by serving out KML With PostgreSQL/PostGIS at the backend, it is possible to perform on-the-fly spatial analysis on the data, right from GE interface! Our current system architecture supports NASA WorldWind through OGC standards such as WMS, WFS (well supported in MapServer)

35 Next Steps (for the immediate future...)

36 Next Steps Deploying the system (Ver. 1) at United Nations Food and Agricultural Organization in Rome, Italy Integrating burned area rasters and provide fast raster query capability Performing system metrics and tuning up the system for faster query speeds. Integrating the system with our other offerings such as the alerts, active data download, Google KML, etc. Developing and Integrating the product with nonbrowser platforms

37 Our other open source projects.. Global Fire Alerts (currently in Beta) Delivers daily fire alerts in a user s area-ofinterest through 100% Open Source, developed using components such as Minnesota MapServer, PHP/MapScript, mscross AJAX API, and PHPMailer subscribers from 75+ countries

38 Check us out You can access all our services from this page.

39 Thank you!