Signature ( GET requests )

signature-get-requests.php

<?php
/**
 *  This snippet implements the logic behing https://github.com/philipbrown/signplz , simply to explain the functionality of generating the auth signature
 *  for non-php programmers so that they can authenticate with the API without a problem.
 **/

$api_key = "";
$api_sec = "";
$url = "http://abc.com/programs/1";
// Method specific options
$method = "GET";
$path = "api/programs/1";

//Query params
$params = array();
$params['auth_version'] = "1.0";
$params['auth_key'] = $api_key;
$params['auth_timestamp'] = time();

$array =  array();
foreach($params as $k => $v)
{
  // Set each param on the array
  $array[strtolower($k)] = $v;
}
ksort($array);
$array = http_build_query($array);

// prepare the string to sign
$string_to_sign = implode("\n", array($method, $path, $array));
echo "<h1> String to Sign : </h1><pre>";
echo $string_to_sign;
echo "</pre></hr>";

//generate the signature
$signature = hash_hmac('sha256', $string_to_sign, $api_sec);
$params['auth_signature'] = $signature;
echo "<h1> Params Posted : </h1><pre>";
print_r(json_encode($params));
echo "</pre></hr>";
// When a GET request is sent the parameters are appended to the Query string. Submitting them as curl post fields has no effect.
$url = $url."?". http_build_query($params);

echo $url;
// Calling the rest api with curl
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
// These curl options are only for POST request.
//curl_setopt($ch, CURLOPT_POST, 1);
//curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($params));
//curl_setopt( $ch, CURLOPT_HTTPHEADER, array('Content-Type:application/json'));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$server_output = curl_exec ($ch);
curl_close ($ch);
echo "<h1> Server Response : </h1>";
echo "<pre>";
print_r($server_output);