Using 2-legged OAuth 1.0 with Google Calendar API

<?php
/**
 * Depends on oauth-php library
 * @link http://code.google.com/p/oauth-php/
 * svn co http://oauth-php.googlecode.com/svn/trunk/library/
 */

abstract class sfGoogleApi {

  protected $developerKey;

  protected $consumerKey;

  protected $consumerSecret;

  protected $requestorId;

  protected $consumer;

  protected $parameters;

  public function __construct($requestId) {

    $this->requestorId = $requestId;

    # Setup Consumer
    $this->developerKey   = sfConfig::get('app_sf_google_api_plugin_developer_key');
    $this->consumerKey    = sfConfig::get('app_sf_google_api_plugin_consumer_key');
    $this->consumerSecret = sfConfig::get('app_sf_google_api_plugin_consumer_secret');

    $this->consumer = new OAuthConsumer($this->consumerKey, $this->consumerSecret, NULL);
    $this->parameters = array(
      'xoauth_requestor_id' => $this->requestorId,
      'key' => $this->developerKey,
    );
  }

  public function getRequestorId() {

    return $this->requestorId;
  }


  /**
   * Makes an HTTP request to the specified URL
   * @param string $http_method The HTTP method (GET, POST, PUT, DELETE)
   * @param string $url Full URL of the resource to access
   * @param string $auth_header (optional) Authorization header
   * @param string $postData (optional) POST/PUT request body
   * @return string Response body from the server
   */
  protected function send_request($http_method, $url, $auth_header=null, $postData=null, $extra_headers = array()) {
    $curl = curl_init($url);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_FAILONERROR, false);
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);

    $headers = array();

    if($auth_header) {
      $headers = array_merge($headers, array($auth_header));
    }

    if($extra_headers) {
      $headers = array_merge($headers, $extra_headers);
    }

    switch($http_method) {
      case 'GET':
        break;
      case 'POST':
        if(!isset($extra_headers['content-type'])) {
          $headers[] = 'Content-Type: application/json; charset=UTF-8';
        } else {
          $headers[] = $extra_headers['content-type'];
        }

        curl_setopt($curl, CURLOPT_POST, 1);
        curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
        break;
      case 'PUT':
        $headers[] = 'Content-Type: application/atom-xml';
        curl_setopt($curl, CURLOPT_CUSTOMREQUEST, $http_method);
        curl_setopt($curl, CURLOPT_POSTFIELDS, $postData);
        break;
      case 'DELETE':
        curl_setopt($curl, CURLOPT_CUSTOMREQUEST, $http_method);
        break;
    }

    curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);
    curl_setopt($curl, CURLOPT_VERBOSE, true);

    $response = curl_exec($curl);
    $code = curl_getinfo($curl, CURLINFO_HTTP_CODE);
    if (!$response) {
      $response = curl_error($curl);
    }

    curl_close($curl);
    return $response;
  }

  /**
   * Joins key:value pairs by inner_glue and each pair together by outer_glue
   * @param string $inner_glue The HTTP method (GET, POST, PUT, DELETE)
   * @param string $outer_glue Full URL of the resource to access
   * @param array $array Associative array of query parameters
   * @return string Urlencoded string of query parameters
   */
  protected function implode_assoc($inner_glue, $outer_glue, $array) {
    $output = array();
    foreach($array as $key => $item) {
      $output[] = $key . $inner_glue . urlencode($item);
    }
    return implode($outer_glue, $output);
  }
}

class sfGoogleApiCalendar extends sfGoogleApi {

  /**
   * Creates a new calendar in Google
   * @param string $title
   * @param string $summary
   * @param boolean $selected
   * @return Zend_Gdata_Calendar_ListEntry
   */
  public function createCalendar($summary, $description, $colorId = 1, $selected = true) {

    $base_feed = 'https://www.googleapis.com/calendar/v3/calendars';

    $request = OAuthRequest::from_consumer_and_token($this->consumer, NULL, 'POST', $base_feed, $this->parameters);
    $request->sign_request(new OAuthSignatureMethod_HMAC_SHA1(), $this->consumer, null);

    $data = json_encode(array(
      'summary'     => $summary,
      'description' => $description,
      'colorId'     => $colorId,
      'selected'    => true
    ));

    // Make signed OAuth request to the Contacts API server
    $url = $base_feed . '?' . $this->implode_assoc('=', '&', $this->parameters);
    $response = $this->send_request($request->get_normalized_http_method(), $url, $request->to_header(), $data);

    $object = json_decode($response);

    if(isset($object->error)) {
      return false;
    }

    return $object;
  }

  /**
   * Returns all calendars for a user
   * @return array[stdClass] An array of all the Calendars
   */
  public function getCalendars() {

    $base_feed = 'https://www.googleapis.com/calendar/v3/users/me/calendarList';
    $request = OAuthRequest::from_consumer_and_token($this->consumer, NULL, 'GET', $base_feed, $this->parameters);
    $request->sign_request(new OAuthSignatureMethod_HMAC_SHA1(), $this->consumer, null);

    // Make signed OAuth request to the Contacts API server
    $url = $base_feed . '?' . $this->implode_assoc('=', '&', $this->parameters);

    $response = $this->send_request($request->get_normalized_http_method(), $url, $request->to_header());

    $object = json_decode($response);

    if(isset($object->error)) {
      return false;
    }

    return $object->items;
  }

  /**
   * Gets a specific calendar.
   * @param string $calendarId
   * @return stdClass|false The Calendar object
   */
  public function getCalendar($calendarId) {

    $base_feed = 'https://www.googleapis.com/calendar/v3/users/me/calendarList/';

    # Get specific calendar
    $base_feed .= $calendarId;

    $request = OAuthRequest::from_consumer_and_token($this->consumer, NULL, 'GET', $base_feed, $this->parameters);
    $request->sign_request(new OAuthSignatureMethod_HMAC_SHA1(), $this->consumer, null);

    // Make signed OAuth request to the Contacts API server
    $url = $base_feed . '?' . $this->implode_assoc('=', '&', $this->parameters);

    $response = $this->send_request($request->get_normalized_http_method(), $url, $request->to_header());

    $object = json_decode($response);

    if(isset($object->error)) {
      return false;
    }

    return $object;
  }

  /**
   * Inserts a new event into the Calendar
   * @param stdClass $event
   * @param string $calendarId
   */
  public function insertEvent($event, $calendarId = null) {

    $base_feed = 'https://www.googleapis.com/calendar/v3/calendars/primary/events';

    if($calendarId) {
      $base_feed = str_replace('primary', $calendarId, $base_feed);
    }

    $request = OAuthRequest::from_consumer_and_token($this->consumer, NULL, 'POST', $base_feed, $this->parameters);
    $request->sign_request(new OAuthSignatureMethod_HMAC_SHA1(), $this->consumer, null);

    $data = json_encode($event);

    // Make signed OAuth request to the Contacts API server
    $url = $base_feed . '?' . $this->implode_assoc('=', '&', $this->parameters);
    $response = $this->send_request($request->get_normalized_http_method(), $url, $request->to_header(), $data);

    $object = json_decode($response);

    if(isset($object->error)) {
      return false;
    }

    return $object;
  }

  /**
   * Executes a batch request to the Google Calendar v2.1
   * @param string $calendarId
   * @param string $batch XML Batch request
   */
  public function executeBatch($calendarId, $batch) {
    $base_feed = 'https://www.google.com/calendar/feeds/'.$calendarId.'/private/full/batch';

    $request = OAuthRequest::from_consumer_and_token($this->consumer, NULL, 'POST', $base_feed, $this->parameters);
    $request->sign_request(new OAuthSignatureMethod_HMAC_SHA1(), $this->consumer, null);

    // Make signed OAuth request to the Contacts API server
    $url = $base_feed . '?' . $this->implode_assoc('=', '&', $this->parameters);
    $response = $this->send_request($request->get_normalized_http_method(), $url, $request->to_header(), $batch,
      array('Gdata-Version: 2.1'));
  }
}

/**
 * Example Use
 */

$sfGoogleCalendar = new sfGoogleCalendar($UserProgram->sfGuardUser->getGoogleUsername());
$calendar = $sfGoogleCalendar->createCalendar($calendarTitle, $calendarSummary);