Gather all the Facebook stuff together in one place

1 files changed, 598 insertions, 0 deletions

diff --git a/plugins/Facebook/facebook/facebook.php b/plugins/Facebook/facebook/facebook.php
new file mode 100644
index 000000000..016e8e8e0
--- /dev/null
+++ b/plugins/Facebook/facebook/facebook.php
@@ -0,0 +1,598 @@
+<?php
+// Copyright 2004-2009 Facebook. All Rights Reserved.
+//
+// +---------------------------------------------------------------------------+
+// | Facebook Platform PHP5 client                                             |
+// +---------------------------------------------------------------------------+
+// | Copyright (c) 2007 Facebook, Inc.                                         |
+// | All rights reserved.                                                      |
+// |                                                                           |
+// | Redistribution and use in source and binary forms, with or without        |
+// | modification, are permitted provided that the following conditions        |
+// | are met:                                                                  |
+// |                                                                           |
+// | 1. Redistributions of source code must retain the above copyright         |
+// |    notice, this list of conditions and the following disclaimer.          |
+// | 2. Redistributions in binary form must reproduce the above copyright      |
+// |    notice, this list of conditions and the following disclaimer in the    |
+// |    documentation and/or other materials provided with the distribution.   |
+// |                                                                           |
+// | THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR      |
+// | IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
+// | OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.   |
+// | IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,          |
+// | INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT  |
+// | NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
+// | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY     |
+// | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT       |
+// | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF  |
+// | THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.         |
+// +---------------------------------------------------------------------------+
+// | For help with this library, contact developers-help@facebook.com          |
+// +---------------------------------------------------------------------------+
+
+include_once 'facebookapi_php5_restlib.php';
+
+define('FACEBOOK_API_VALIDATION_ERROR', 1);
+class Facebook {
+  public $api_client;
+  public $api_key;
+  public $secret;
+  public $generate_session_secret;
+  public $session_expires;
+
+  public $fb_params;
+  public $user;
+  public $profile_user;
+  public $canvas_user;
+  protected $base_domain;
+  /*
+   * Create a Facebook client like this:
+   *
+   * $fb = new Facebook(API_KEY, SECRET);
+   *
+   * This will automatically pull in any parameters, validate them against the
+   * session signature, and chuck them in the public $fb_params member variable.
+   *
+   * @param api_key                  your Developer API key
+   * @param secret                   your Developer API secret
+   * @param generate_session_secret  whether to automatically generate a session
+   *                                 if the user doesn't have one, but
+   *                                 there is an auth token present in the url,
+   */
+  public function __construct($api_key, $secret, $generate_session_secret=false) {
+    $this->api_key                 = $api_key;
+    $this->secret                  = $secret;
+    $this->generate_session_secret = $generate_session_secret;
+    $this->api_client = new FacebookRestClient($api_key, $secret, null);
+    $this->validate_fb_params();
+
+    // Set the default user id for methods that allow the caller to
+    // pass an explicit uid instead of using a session key.
+    $defaultUser = null;
+    if ($this->user) {
+      $defaultUser = $this->user;
+    } else if ($this->profile_user) {
+      $defaultUser = $this->profile_user;
+    } else if ($this->canvas_user) {
+      $defaultUser = $this->canvas_user;
+    }
+
+    $this->api_client->set_user($defaultUser);
+
+
+    if (isset($this->fb_params['friends'])) {
+      $this->api_client->friends_list = explode(',', $this->fb_params['friends']);
+    }
+    if (isset($this->fb_params['added'])) {
+      $this->api_client->added = $this->fb_params['added'];
+    }
+    if (isset($this->fb_params['canvas_user'])) {
+      $this->api_client->canvas_user = $this->fb_params['canvas_user'];
+    }
+  }
+
+  /*
+   * Validates that the parameters passed in were sent from Facebook. It does so
+   * by validating that the signature matches one that could only be generated
+   * by using your application's secret key.
+   *
+   * Facebook-provided parameters will come from $_POST, $_GET, or $_COOKIE,
+   * in that order. $_POST and $_GET are always more up-to-date than cookies,
+   * so we prefer those if they are available.
+   *
+   * For nitty-gritty details of when each of these is used, check out
+   * http://wiki.developers.facebook.com/index.php/Verifying_The_Signature
+   *
+   * @param bool  resolve_auth_token  convert an auth token into a session
+   */
+  public function validate_fb_params($resolve_auth_token=true) {
+    $this->fb_params = $this->get_valid_fb_params($_POST, 48 * 3600, 'fb_sig');
+
+    // note that with preload FQL, it's possible to receive POST params in
+    // addition to GET, so use a different prefix to differentiate them
+    if (!$this->fb_params) {
+      $fb_params = $this->get_valid_fb_params($_GET, 48 * 3600, 'fb_sig');
+      $fb_post_params = $this->get_valid_fb_params($_POST, 48 * 3600, 'fb_post_sig');
+      $this->fb_params = array_merge($fb_params, $fb_post_params);
+    }
+
+    // Okay, something came in via POST or GET
+    if ($this->fb_params) {
+      $user               = isset($this->fb_params['user']) ?
+                            $this->fb_params['user'] : null;
+      $this->profile_user = isset($this->fb_params['profile_user']) ?
+                            $this->fb_params['profile_user'] : null;
+      $this->canvas_user  = isset($this->fb_params['canvas_user']) ?
+                            $this->fb_params['canvas_user'] : null;
+      $this->base_domain  = isset($this->fb_params['base_domain']) ?
+                            $this->fb_params['base_domain'] : null;
+
+      if (isset($this->fb_params['session_key'])) {
+        $session_key =  $this->fb_params['session_key'];
+      } else if (isset($this->fb_params['profile_session_key'])) {
+        $session_key =  $this->fb_params['profile_session_key'];
+      } else {
+        $session_key = null;
+      }
+      $expires     = isset($this->fb_params['expires']) ?
+                     $this->fb_params['expires'] : null;
+      $this->set_user($user,
+                      $session_key,
+                      $expires);
+    }
+    // if no Facebook parameters were found in the GET or POST variables,
+    // then fall back to cookies, which may have cached user information
+    // Cookies are also used to receive session data via the Javascript API
+    else if ($cookies =
+             $this->get_valid_fb_params($_COOKIE, null, $this->api_key)) {
+
+      $base_domain_cookie = 'base_domain_' . $this->api_key;
+      if (isset($_COOKIE[$base_domain_cookie])) {
+        $this->base_domain = $_COOKIE[$base_domain_cookie];
+      }
+
+      // use $api_key . '_' as a prefix for the cookies in case there are
+      // multiple facebook clients on the same domain.
+      $expires = isset($cookies['expires']) ? $cookies['expires'] : null;
+      $this->set_user($cookies['user'],
+                      $cookies['session_key'],
+                      $expires);
+    }
+    // finally, if we received no parameters, but the 'auth_token' GET var
+    // is present, then we are in the middle of auth handshake,
+    // so go ahead and create the session
+    else if ($resolve_auth_token && isset($_GET['auth_token']) &&
+             $session = $this->do_get_session($_GET['auth_token'])) {
+      if ($this->generate_session_secret &&
+          !empty($session['secret'])) {
+        $session_secret = $session['secret'];
+      }
+
+      if (isset($session['base_domain'])) {
+        $this->base_domain = $session['base_domain'];
+      }
+
+      $this->set_user($session['uid'],
+                      $session['session_key'],
+                      $session['expires'],
+                      isset($session_secret) ? $session_secret : null);
+    }
+
+    return !empty($this->fb_params);
+  }
+
+  // Store a temporary session secret for the current session
+  // for use with the JS client library
+  public function promote_session() {
+    try {
+      $session_secret = $this->api_client->auth_promoteSession();
+      if (!$this->in_fb_canvas()) {
+        $this->set_cookies($this->user, $this->api_client->session_key, $this->session_expires, $session_secret);
+      }
+      return $session_secret;
+    } catch (FacebookRestClientException $e) {
+      // API_EC_PARAM means we don't have a logged in user, otherwise who
+      // knows what it means, so just throw it.
+      if ($e->getCode() != FacebookAPIErrorCodes::API_EC_PARAM) {
+        throw $e;
+      }
+    }
+  }
+
+  public function do_get_session($auth_token) {
+    try {
+      return $this->api_client->auth_getSession($auth_token, $this->generate_session_secret);
+    } catch (FacebookRestClientException $e) {
+      // API_EC_PARAM means we don't have a logged in user, otherwise who
+      // knows what it means, so just throw it.
+      if ($e->getCode() != FacebookAPIErrorCodes::API_EC_PARAM) {
+        throw $e;
+      }
+    }
+  }
+
+  // Invalidate the session currently being used, and clear any state associated
+  // with it. Note that the user will still remain logged into Facebook.
+  public function expire_session() {
+    if ($this->api_client->auth_expireSession()) {
+      $this->clear_cookie_state();
+      return true;
+    } else {
+      return false;
+    }
+  }
+
+  /** Logs the user out of all temporary application sessions as well as their
+   * Facebook session.  Note this will only work if the user has a valid current
+   * session with the application.
+   *
+   * @param string  $next  URL to redirect to upon logging out
+   *
+   */
+   public function logout($next) {
+    $logout_url = $this->get_logout_url($next);
+
+    // Clear any stored state
+    $this->clear_cookie_state();
+
+    $this->redirect($logout_url);
+  }
+
+  /**
+   *  Clears any persistent state stored about the user, including
+   *  cookies and information related to the current session in the
+   *  client.
+   *
+   */
+  public function clear_cookie_state() {
+    if (!$this->in_fb_canvas() && isset($_COOKIE[$this->api_key . '_user'])) {
+       $cookies = array('user', 'session_key', 'expires', 'ss');
+       foreach ($cookies as $name) {
+         setcookie($this->api_key . '_' . $name, false, time() - 3600);
+         unset($_COOKIE[$this->api_key . '_' . $name]);
+       }
+       setcookie($this->api_key, false, time() - 3600);
+       unset($_COOKIE[$this->api_key]);
+     }
+
+     // now, clear the rest of the stored state
+     $this->user = 0;
+     $this->api_client->session_key = 0;
+  }
+
+  public function redirect($url) {
+    if ($this->in_fb_canvas()) {
+      echo '<fb:redirect url="' . $url . '"/>';
+    } else if (preg_match('/^https?:\/\/([^\/]*\.)?facebook\.com(:\d+)?/i', $url)) {
+      // make sure facebook.com url's load in the full frame so that we don't
+      // get a frame within a frame.
+      echo "<script type=\"text/javascript\">\ntop.location.href = \"$url\";\n</script>";
+    } else {
+      header('Location: ' . $url);
+    }
+    exit;
+  }
+
+  public function in_frame() {
+    return isset($this->fb_params['in_canvas'])
+        || isset($this->fb_params['in_iframe']);
+  }
+  public function in_fb_canvas() {
+    return isset($this->fb_params['in_canvas']);
+  }
+
+  public function get_loggedin_user() {
+    return $this->user;
+  }
+
+  public function get_canvas_user() {
+    return $this->canvas_user;
+  }
+
+  public function get_profile_user() {
+    return $this->profile_user;
+  }
+
+  public static function current_url() {
+    return 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
+  }
+
+  // require_add and require_install have been removed.
+  // see http://developer.facebook.com/news.php?blog=1&story=116 for more details
+  public function require_login() {
+    if ($user = $this->get_loggedin_user()) {
+      return $user;
+    }
+    $this->redirect($this->get_login_url(self::current_url(), $this->in_frame()));
+  }
+
+  public function require_frame() {
+    if (!$this->in_frame()) {
+      $this->redirect($this->get_login_url(self::current_url(), true));
+    }
+  }
+
+  public static function get_facebook_url($subdomain='www') {
+    return 'http://' . $subdomain . '.facebook.com';
+  }
+
+  public function get_install_url($next=null) {
+    // this was renamed, keeping for compatibility's sake
+    return $this->get_add_url($next);
+  }
+
+  public function get_add_url($next=null) {
+    $page = self::get_facebook_url().'/add.php';
+    $params = array('api_key' => $this->api_key);
+
+    if ($next) {
+      $params['next'] = $next;
+    }
+
+    return $page . '?' . http_build_query($params);
+  }
+
+  public function get_login_url($next, $canvas) {
+    $page = self::get_facebook_url().'/login.php';
+    $params = array('api_key' => $this->api_key,
+                    'v'       => '1.0');
+
+    if ($next) {
+      $params['next'] = $next;
+    }
+    if ($canvas) {
+      $params['canvas'] = '1';
+    }
+
+    return $page . '?' . http_build_query($params);
+  }
+
+  public function get_logout_url($next) {
+    $page = self::get_facebook_url().'/logout.php';
+    $params = array('app_key'     => $this->api_key,
+                    'session_key' => $this->api_client->session_key);
+
+    if ($next) {
+      $params['connect_next'] = 1;
+      $params['next'] = $next;
+    }
+
+    return $page . '?' . http_build_query($params);
+  }
+
+  public function set_user($user, $session_key, $expires=null, $session_secret=null) {
+    if (!$this->in_fb_canvas() && (!isset($_COOKIE[$this->api_key . '_user'])
+                                   || $_COOKIE[$this->api_key . '_user'] != $user)) {
+      $this->set_cookies($user, $session_key, $expires, $session_secret);
+    }
+    $this->user = $user;
+    $this->api_client->session_key = $session_key;
+    $this->session_expires = $expires;
+  }
+
+  public function set_cookies($user, $session_key, $expires=null, $session_secret=null) {
+    $cookies = array();
+    $cookies['user'] = $user;
+    $cookies['session_key'] = $session_key;
+    if ($expires != null) {
+      $cookies['expires'] = $expires;
+    }
+    if ($session_secret != null) {
+      $cookies['ss'] = $session_secret;
+    }
+
+    foreach ($cookies as $name => $val) {
+      setcookie($this->api_key . '_' . $name, $val, (int)$expires, '', $this->base_domain);
+      $_COOKIE[$this->api_key . '_' . $name] = $val;
+    }
+    $sig = self::generate_sig($cookies, $this->secret);
+    setcookie($this->api_key, $sig, (int)$expires, '', $this->base_domain);
+    $_COOKIE[$this->api_key] = $sig;
+
+    if ($this->base_domain != null) {
+      $base_domain_cookie = 'base_domain_' . $this->api_key;
+      setcookie($base_domain_cookie, $this->base_domain, (int)$expires, '', $this->base_domain);
+      $_COOKIE[$base_domain_cookie] = $this->base_domain;
+    }
+  }
+
+  /**
+   * Tries to undo the badness of magic quotes as best we can
+   * @param     string   $val   Should come directly from $_GET, $_POST, etc.
+   * @return    string   val without added slashes
+   */
+  public static function no_magic_quotes($val) {
+    if (get_magic_quotes_gpc()) {
+      return stripslashes($val);
+    } else {
+      return $val;
+    }
+  }
+
+  /*
+   * Get the signed parameters that were sent from Facebook. Validates the set
+   * of parameters against the included signature.
+   *
+   * Since Facebook sends data to your callback URL via unsecured means, the
+   * signature is the only way to make sure that the data actually came from
+   * Facebook. So if an app receives a request at the callback URL, it should
+   * always verify the signature that comes with against your own secret key.
+   * Otherwise, it's possible for someone to spoof a request by
+   * pretending to be someone else, i.e.:
+   *      www.your-callback-url.com/?fb_user=10101
+   *
+   * This is done automatically by verify_fb_params.
+   *
+   * @param  assoc  $params     a full array of external parameters.
+   *                            presumed $_GET, $_POST, or $_COOKIE
+   * @param  int    $timeout    number of seconds that the args are good for.
+   *                            Specifically good for forcing cookies to expire.
+   * @param  string $namespace  prefix string for the set of parameters we want
+   *                            to verify. i.e., fb_sig or fb_post_sig
+   *
+   * @return  assoc the subset of parameters containing the given prefix,
+   *                and also matching the signature associated with them.
+   *          OR    an empty array if the params do not validate
+   */
+  public function get_valid_fb_params($params, $timeout=null, $namespace='fb_sig') {
+    $prefix = $namespace . '_';
+    $prefix_len = strlen($prefix);
+    $fb_params = array();
+    if (empty($params)) {
+      return array();
+    }
+
+    foreach ($params as $name => $val) {
+      // pull out only those parameters that match the prefix
+      // note that the signature itself ($params[$namespace]) is not in the list
+      if (strpos($name, $prefix) === 0) {
+        $fb_params[substr($name, $prefix_len)] = self::no_magic_quotes($val);
+      }
+    }
+
+    // validate that the request hasn't expired. this is most likely
+    // for params that come from $_COOKIE
+    if ($timeout && (!isset($fb_params['time']) || time() - $fb_params['time'] > $timeout)) {
+      return array();
+    }
+
+    // validate that the params match the signature
+    $signature = isset($params[$namespace]) ? $params[$namespace] : null;
+    if (!$signature || (!$this->verify_signature($fb_params, $signature))) {
+      return array();
+    }
+    return $fb_params;
+  }
+
+  /**
+   *  Validates the account that a user was trying to set up an
+   *  independent account through Facebook Connect.
+   *
+   *  @param  user The user attempting to set up an independent account.
+   *  @param  hash The hash passed to the reclamation URL used.
+   *  @return bool True if the user is the one that selected the
+   *               reclamation link.
+   */
+  public function verify_account_reclamation($user, $hash) {
+    return $hash == md5($user . $this->secret);
+  }
+
+  /**
+   * Validates that a given set of parameters match their signature.
+   * Parameters all match a given input prefix, such as "fb_sig".
+   *
+   * @param $fb_params     an array of all Facebook-sent parameters,
+   *                       not including the signature itself
+   * @param $expected_sig  the expected result to check against
+   */
+  public function verify_signature($fb_params, $expected_sig) {
+    return self::generate_sig($fb_params, $this->secret) == $expected_sig;
+  }
+
+  /**
+   * Validate the given signed public session data structure with
+   * public key of the app that
+   * the session proof belongs to.
+   *
+   * @param $signed_data the session info that is passed by another app
+   * @param string $public_key Optional public key of the app. If this
+   *               is not passed, function will make an API call to get it.
+   * return true if the session proof passed verification.
+   */
+  public function verify_signed_public_session_data($signed_data,
+                                                    $public_key = null) {
+
+    // If public key is not already provided, we need to get it through API
+    if (!$public_key) {
+      $public_key = $this->api_client->auth_getAppPublicKey(
+        $signed_data['api_key']);
+    }
+
+    // Create data to verify
+    $data_to_serialize = $signed_data;
+    unset($data_to_serialize['sig']);
+    $serialized_data = implode('_', $data_to_serialize);
+
+    // Decode signature
+    $signature = base64_decode($signed_data['sig']);
+    $result = openssl_verify($serialized_data, $signature, $public_key,
+                             OPENSSL_ALGO_SHA1);
+    return $result == 1;
+  }
+
+  /*
+   * Generate a signature using the application secret key.
+   *
+   * The only two entities that know your secret key are you and Facebook,
+   * according to the Terms of Service. Since nobody else can generate
+   * the signature, you can rely on it to verify that the information
+   * came from Facebook.
+   *
+   * @param $params_array   an array of all Facebook-sent parameters,
+   *                        NOT INCLUDING the signature itself
+   * @param $secret         your app's secret key
+   *
+   * @return a hash to be checked against the signature provided by Facebook
+   */
+  public static function generate_sig($params_array, $secret) {
+    $str = '';
+
+    ksort($params_array);
+    // Note: make sure that the signature parameter is not already included in
+    //       $params_array.
+    foreach ($params_array as $k=>$v) {
+      $str .= "$k=$v";
+    }
+    $str .= $secret;
+
+    return md5($str);
+  }
+
+  public function encode_validationError($summary, $message) {
+    return json_encode(
+               array('errorCode'    => FACEBOOK_API_VALIDATION_ERROR,
+                     'errorTitle'   => $summary,
+                     'errorMessage' => $message));
+  }
+
+  public function encode_multiFeedStory($feed, $next) {
+    return json_encode(
+               array('method'   => 'multiFeedStory',
+                     'content'  =>
+                     array('next' => $next,
+                           'feed' => $feed)));
+  }
+
+  public function encode_feedStory($feed, $next) {
+    return json_encode(
+               array('method'   => 'feedStory',
+                     'content'  =>
+                     array('next' => $next,
+                           'feed' => $feed)));
+  }
+
+  public function create_templatizedFeedStory($title_template, $title_data=array(),
+                                    $body_template='', $body_data = array(), $body_general=null,
+                                    $image_1=null, $image_1_link=null,
+                                    $image_2=null, $image_2_link=null,
+                                    $image_3=null, $image_3_link=null,
+                                    $image_4=null, $image_4_link=null) {
+    return array('title_template'=> $title_template,
+                 'title_data'   => $title_data,
+                 'body_template'=> $body_template,
+                 'body_data'    => $body_data,
+                 'body_general' => $body_general,
+                 'image_1'      => $image_1,
+                 'image_1_link' => $image_1_link,
+                 'image_2'      => $image_2,
+                 'image_2_link' => $image_2_link,
+                 'image_3'      => $image_3,
+                 'image_3_link' => $image_3_link,
+                 'image_4'      => $image_4,
+                 'image_4_link' => $image_4_link);
+  }
+
+
+}
+