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PHP Extension

URL Signing for Google Maps API

See more Encryption Examples

Demonstrates how to sign a URL for the Google Maps API.

Chilkat PHP Extension Downloads

PHP Extension
<?php

include("chilkat.php");

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

$crypt = new CkCrypt2();

// The output will be modified Base64.
// Modified Base64 for URLs replaces the '+' and '/' characters 
// of standard Base64 with '-' and '_' respectively, so that these 
// Base64 signatures no longer need to be URL-encoded.
$crypt->put_EncodingMode('modBase64');

// Set the hash algorithm to sha-1
$crypt->put_HashAlgorithm('sha-1');
$crypt->put_MacAlgorithm('hmac');

// Set the HMAC key (this is the private key provided by Google)
$crypt->SetMacKeyEncoded('vNIXE0xscrmjlyV-12Nj_BvUPaw=','modBase64');

// Compute the URL signature
$sig = $crypt->macStringENC('/maps/api/geocode/json?address=New+York&sensor=false&client=clientID');

// The result should be KrU1TzVQM7Ur0i8i7K3huiw3MsA=
print $sig . "\n";

?>