Redu PHP Client with OAuth

redu_client.php

<?php
// this script requires the instalation of the Oauth library
// http://br.php.net/manual/en/book.oauth.php

$api_url = 'http://www.redu.com.br/api';
$authorize_url = 'http://www.redu.com.br/oauth/authorize';
$request_token_url = 'http://www.redu.com.br/oauth/request_token';
$access_token_url = 'http://www.redu.com.br/oauth/access_token';

$consumer_key = 'PUT_YOUR_CONSUMER_KEY_HERE';
$consumer_secret = 'PUT_YOUR_CONSUMER_SECRET_HERE';

session_start();
// In state=1 the next request should include an oauth_token.
// If it doesn't go back to 0
if(!isset($_GET['oauth_token']) && $_SESSION['state']==1) {
  $_SESSION['state'] = 0;
}

try {
  $oauth = new OAuth($consumer_key,
                     $consumer_secret,
                     OAUTH_SIG_METHOD_HMACSHA1,
                     OAUTH_AUTH_TYPE_URI);
  $oauth->enableDebug();

  if(!isset($_GET['oauth_token']) && !$_SESSION['state']) {
    $request_token_info = $oauth->getRequestToken($request_token_url);
    $_SESSION['secret'] = $request_token_info['oauth_token_secret'];
    $_SESSION['state'] = 1;
    header('Location: '.$authorize_url.'?oauth_token='.$request_token_info['oauth_token']);
    exit;
  } else if($_SESSION['state']==1) {
    $oauth->setToken($_GET['oauth_token'],$_SESSION['secret']);
    $access_token_info = $oauth->getAccessToken($access_token_url);
    $_SESSION['state'] = 2;
    $_SESSION['token'] = $access_token_info['oauth_token'];
    $_SESSION['secret'] = $access_token_info['oauth_token_secret'];
  }

  $oauth->setToken($_SESSION['token'],$_SESSION['secret']);
  // fetching Redu Environments
  $oauth->fetch("$api_url/environments.json");
  $json = json_decode($oauth->getLastResponse());
  var_dump($json);
} catch(OAuthException $E) {
  var_dump($E);
}
?>