Creating a Facebook Page Tab App using the Facebook PHP SDK 4.0.x

fb_tab_app_4.0.x.php

<?php
// required Facebook PHP SDK v4.0.9 or later.
 
// include required files form Facebook SDK
require_once( 'Facebook/HttpClients/FacebookHttpable.php' );
require_once( 'Facebook/HttpClients/FacebookCurl.php' );
require_once( 'Facebook/HttpClients/FacebookCurlHttpClient.php' );
 
require_once( 'Facebook/Entities/AccessToken.php' );
require_once( 'Facebook/Entities/SignedRequest.php' );
 
require_once( 'Facebook/FacebookSession.php' );
require_once( 'Facebook/FacebookRedirectLoginHelper.php' );
require_once( 'Facebook/FacebookSignedRequestFromInputHelper.php' ); // added in v4.0.9
require_once( 'Facebook/FacebookRequest.php' );
require_once( 'Facebook/FacebookResponse.php' );
require_once( 'Facebook/FacebookSDKException.php' );
require_once( 'Facebook/FacebookRequestException.php' );
require_once( 'Facebook/FacebookOtherException.php' );
require_once( 'Facebook/FacebookAuthorizationException.php' );
 
// these two classes required for canvas and tab apps
require_once( 'Facebook/FacebookCanvasLoginHelper.php' );
require_once( 'Facebook/FacebookPageTabHelper.php' );
 
require_once( 'Facebook/GraphObject.php' );
require_once( 'Facebook/GraphSessionInfo.php' );
 
use Facebook\HttpClients\FacebookHttpable;
use Facebook\HttpClients\FacebookCurl;
use Facebook\HttpClients\FacebookCurlHttpClient;
 
use Facebook\Entities\AccessToken;
use Facebook\Entities\SignedRequest;
 
use Facebook\FacebookSession;
use Facebook\FacebookRedirectLoginHelper;
use Facebook\FacebookSignedRequestFromInputHelper; // added in v4.0.9
use Facebook\FacebookRequest;
use Facebook\FacebookResponse;
use Facebook\FacebookSDKException;
use Facebook\FacebookRequestException;
use Facebook\FacebookOtherException;
use Facebook\FacebookAuthorizationException;
use Facebook\GraphObject;
use Facebook\GraphSessionInfo;
 
// these two classes required for canvas and tab apps
use Facebook\FacebookCanvasLoginHelper;
use Facebook\FacebookPageTabHelper;
 
// start session
session_start();
 
// init app with app id and secret
FacebookSession::setDefaultApplication( 'xxx','yyy' );
 
// init login helper
$helper = new FacebookRedirectLoginHelper( 'http://sites.local/php-sdk-4.0/redirect.php' );
 
// init page tab helper
$pageHelper = new FacebookPageTabHelper();
 
// get session from the page
$session = $pageHelper->getSession();
 
// get page_id
echo '<p>You are currently viewing page: '. $pageHelper->getPageId() . '</p>';
 
// get like status - use for likegates
echo '<p>You have '. ( $pageHelper->isLiked() ? 'LIKED' : 'NOT liked' ) . ' this page</p>';
 
// get admin status
echo '<p>You are '. ( $pageHelper->isAdmin() ? 'an ADMIN' : 'NOT an ADMIN' ) . '</p>';
 
// see if we have a session
if ( isset( $session ) ) {
  
  // show logged-in user id
  echo 'User Id: ' . $pageHelper->getUserId();
  
  // graph api request for user data
  $request = new FacebookRequest( $session, 'GET', '/me' );
  $response = $request->execute();
  // get response
  $graphObject = $response->getGraphObject()->asArray();
  
  // print profile data
  echo '<pre>' . print_r( $graphObject, 1 ) . '</pre>';
  
  // print logout url, target = _top to break out of page frame
  echo '<a href="' . $helper->getLogoutUrl( $session, 'http://sites.local/php-sdk-4.0/redirect.php' ) . '" target="_top">Logout</a>';
  
} else {
  // show login url, target = _top to break out of page frame
  echo '<a href="' . $helper->getLoginUrl( array( 'email', 'user_friends' ) ) . '" target="_top">Login</a>';
}

gistfile1.txt

$helper = new FacebookRedirectLoginHelper( 'http://sites.local/php-sdk-4.0/redirect.php' );

What does redirect.php do?