I'm trying to create a module that creates a Shortlink using Google Apps Shortlink Api (undocumented since its still in labs).

Here's the script (also at http://drupalbin.com/18667):

    function drapps_shortlinks_createlink($url, $verbose = FALSE, $bypass_validattion = FALSE) {
      //loads ShortLink Class
      include_once('ShortLink.php');
           
      // URL validation with 2 clauses:
      // 1 - FILTER_VALIDATE_URL -> tests if the url is well constructed
      // 2 - @fopen -> tests if the URL actually exist
      if (!filter_var($url, FILTER_VALIDATE_URL) OR !@fopen($url,"r")) {
        // URL not valid or inexistant, so bail
        if ($verbose) {
          $msg = 'Invalid URL';
          return $msg;
        }
        else {
          return;
        }
      }
           
      // Get configuration values
      $domain = 'mydomain.com';
      $key = 'someHMACKEY';
      $user = '[email protected]';
         
      // Check if user admin has configured DRAPPS and DRAPPS ShortLinks
      if (!$domain OR !$key OR !$user) {
        //Something is missing so bail
        if ($verbose) {
          $msg = 'DRAPPS Shortlinks is not configured. Please go to <a href="' . base_path() . 'admin/settings/drapps">admin/settings/drapps</a>';
          return $msg;
        }
        else {
          return;
        }
      }
     
      //PHP Google Apps ShortLinks Implementation
      $slink = new ShortLink($domain, $key, $user);
      $r = clone $slink->pub($url);
      $status = $r->status;

      if ($status == 'ok') {
        return $r;
      }
      elseif ($verbose) {
        return $status;
      }
      else {
        return;
      }
    }

This script uses a custom created class called [SHortLink.php][1].  

EDIT: This function is called in Drupal's node-news.tpl.php like this:

    ...
    <div class="test"><?php print drapps_shortlinks_createlink($url, TRUE, FALSE); ?></div>
    ...

test.php

    <?php
    
    $path = "path/to/drupal"; //changed for security reasons
    
    include_once($path . 'sites/all/modules/drapps_shortlinks/drapps_shortlinks.inc');
    
    $url = 'http://www.google.com/';

    print drapps_shortlinks_createlink($url, TRUE, FALSE);
    
    ?>


When I go to http://www.mydomain.com/test/test.php, the script works fine and I get an 'ok' response from google; a short link is created and it works fine. When I navigate to a news node, the script runs OK, but Google responds with a 403 (forbidden) error.

 EDIT_1: THIS SCRIPT WORKS. So i think I can safely assume that the reson behind this has something to do with drupal rather than the script itself.


 EDIT_2: I think the real question behind this is: What reasons could make a script behave differently when called from drupal? Any input will be appreciated: brainstorming, ideas, tips, troubleshooting methods, anything you think that might help, I will really appreciate it. 

  [1]: http://pastebin.com/cXLe6R35