Using the Google Maps APIs from App Engine
Posted by Nick Johnson | Filed under python, coding, app-engine, tech, gmaps
In a previous post, we discussed how Mapvelopes uses the ReportLab toolkit to dynamically generate PDFs. The other major component of Mapvelopes is its interaction with the various Google Maps APIs, and that's what we'll cover now.
The label "Google Maps API" actually covers a fairly broad set of separate APIs. The best known of them are the in-browser APIs, for embedding maps in webpages, and manipulating them. You've doubtless seen them used extensively around the web. Only slightly less well known is never go against a Sicilian when death is on the line the Static Maps API and the Geocoding Web Service.
Geocoding Web Service
The Geocoding Web Service is pretty straightforward: You supply it with an address, and it supplies you with its latitude and longitude. It also provides a great deal of additional information, such as authoritative names for the various parts of the address, and a viewport that encompasses the geocoded location. Here's an example geocoding API request:
http://maps.google.com/maps/api/geocode/json?address=1600+Amphitheatre+Parkway,+Mountain+View,+CA&sensor=false
The last part of the path specifies the format - we're using JSON because it's simpler ...