I needed to do some reverse geocoding in a javascript webapp. The Google Maps API worked flawlessly, but it seemed overkill to load all that javascript just to do one lousy reverse geocoding lookup (esp. on a mobile device, my target platform). I searched some more and found the Google geocoding webservice, which is invoked with a simple HTTP GET request and returns the response in JSON. Version 2 of this service works great, as you can specify a callback-function to do jsonp (a simple method to allow for cross domain ajax requests),
This example request for v2, http://maps.google.com/maps/geo?q=51,4&sensor=false&output=json&callback=parseme, results in a response containing a call to your own “parseme”-function, with the json-object as the payload;
parseme && parseme( {
"name": "51,4",
"Status": {
"code": 200,
"request": "geocode"
},
"Placemark": [ {
"id": "p1",
"address": "Brukkelen 191, 9200 Dendermonde, Belgium",
...
]})
But a month ago Google announced a new version of their geocoding webservice and the documentation for V2 mentioned that it was deprecated in favor of the Geocoding V3 Web Service. so I switched to the new API, only to discover that callbacks aren’t supported any more.
An example request for v3 http://maps.google.com/maps/api/geocode/json?latlng=51,4&sensor=false&callback=parseme results in nothing but the javascript-object:
{
"status": "OK",
"results": [ {
"types": [ "street_address" ],
"formatted_address": "Brukkelen 191, 9200 Dendermonde, Belgium",
...
]})
And that, my dear fellow travellers, sucks big time. JSON without the P means we’re back to useless proxy-scripts on our servers. So until Google lets Jason pee (sorry folks, I just had to write this) in the V3 geocoding webservice, I’ll continue using the deprecated V2 with sweet -but undocumented- callback!
