Code a geodata app using Google Maps

Before Google Maps, Geographic Information Systems (GIS) were proprietary, expensive, arcane. Now, thanks to the GMaps API, in two weeks I was able to build my own mapping application. Along the way I wrote a bunch of reusable classes for calculating distances, clustering by proximity, decluttering … all the features that used to cost big bucks.

Open-source software and what is sometimes called the Age of Mass Amateurization also have their troubling side, of course. Example: my income today is roughly a third of what it was in 2000. But since there seems to be no going back, I take pleasure in having an ever-growing toolset and community in which to play.

This turned out to be an excellent re-introduction to web development, after I spent the last three years teaching 8th-grade science. My greatest challenges were:

• converting address files (in CSV format) to XML
• writing an XML_RPC client to access geocoder.us, which returns lat/long data
• fussing with XHTML and CSS so I could produdly put Valid stickers on my pages

The Google Mapping API itself is trivial.

Now I’m writing some filtering code to turn on/off map markers and show distances in miles from the school to various addresses. Yay!

Turns out the interface is not via SOAP/Web Services after all, but a simple, remarkably functional Javascript API. Am coding up a data-driven pushpin map of families in the private school where my wife works. Sound productizable?

Plan to access the newly opened Maps API using Perl’s SOAP:Lite. Be interesting to code it up in Java as well and compare development time, performance, maintainability.