Idle Hacking

Tonight I was experimenting with google maps and geocoding. It turns out it’s not too difficult to extract geocoordinates from google maps. Basically, the key is to add the extra query parameter ouput=js

Once you do that google outputs the response as javascript with a nice xml document embedded within. Using a few regular expressions to extract the xml and we have some very sophisticated results from our friends google.

The following is a very simple example, in php that searches for a location near DC. What someone might want to do with this little trickier and googles nice javascript api is beyond me

header('Content-Type: text/xml');

$address = strip_tags($_GET["address"]);
$query = 'http://maps.google.com/maps?q=' .
urlencode( $address ) .
'&sll=38.880660,-77.114642&sspn=0.023753,0.039439&hl=en' . // near DC
'&output=js';

$gm = fopen( $query, 'r' );
if( !$gm ){
return;
}
$buffer = "";
while( !feof( $gm ) ){
$buffer .= fgets($gm, 4096);
}
fclose($gm);

// correct end tags
// "/\\\//\//g"
$buffer = preg_replace( "/<\/\\//", "";
$locs = $doc->getElementsByTagName( "locations" );
echo $doc->saveXML($locs->item(0)) . "\n";

Update

This no longer works.  Google started returning JSON.  Also, google now has GeoCoding built in to their API.

Software Geo Coding, Google Maps, Javascript, PHP