Facebook php sdk 4.0 发布消息到用户时间线

我的php代码将您登录到Facebook以成功授予权限。然后它会检索您的个人资料图片和名称。我还在尝试运行一个脚本，允许用户将消息发布到他的时间线。目前它运行错误代码 200，我不确定如何处理这个问题。

这是我的应用程序 http://www.vle.co.nz/fb/的链接，我的代码也在下面。

<?php
require_once('src/Facebook/Entities/AccessToken.php');
require_once('src/Facebook/HttpClients/FacebookHttpable.php');
require_once('src/Facebook/HttpClients/FacebookCurl.php');
require_once('src/Facebook/HttpClients/FacebookCurlHttpClient.php');
require_once('src/Facebook/FacebookSDKException.php');
require_once('src/Facebook/FacebookRequestException.php');
require_once('src/Facebook/FacebookPermissionException.php' );
require_once('src/Facebook/FacebookAuthorizationException.php');
require_once('src/Facebook/FacebookRedirectLoginHelper.php');
require_once('src/Facebook/FacebookRequest.php');
require_once('src/Facebook/FacebookResponse.php');
require_once('src/Facebook/FacebookSession.php');
require_once('src/Facebook/GraphObject.php');
require_once('src/Facebook/GraphSessionInfo.php');
require_once('src/Facebook/GraphUser.php');
use Facebook'FacebookCurl;
use Facebook'FacebookCurlHttpClient;
use Facebook'FacebookHttpable;
use Facebook'FacebookAuthorizationException;
use Facebook'FacebookRedirectLoginHelper;
use Facebook'FacebookRequest;
use Facebook'FacebookRequestException;
use Facebook'FacebookResponse;
use Facebook'FacebookSDKException;
use Facebook'FacebookSession;
use Facebook'GraphObject;
use Facebook'GraphSessionInfo;
use Facebook'GraphUser;
try {
  session_start();
  $app_id = '1619082794989827';
  $app_secret = '3b9c9c607ab5529561bdac8c5944a9bb';
  $redirect_url = 'http://www.vle.co.nz/fb/';
  FacebookSession::setDefaultApplication($app_id, $app_secret);
  $helper = new FacebookRedirectLoginHelper($redirect_url);
  $sess = $helper->getSessionFromRedirect();
  if(isset($sess)) {
    $accessToken = $sess->getAccessToken();
    $_SESSION['fb_token'] = $accessToken->extend(); 
    $request = new FacebookRequest($sess, 'GET', '/me');
    $response = $request->execute();
    $graph = $response->getGraphObject(GraphUser::classname());
    $name = $graph->getName();
    $id = $graph->getId();
    $image = 'http://graph.facebook.com/'.$id.'/picture?width=300';
    echo "<img src='$image' /><br/>";
    echo "Hello $name <br>";
    echo "Email: $email <br>";
    echo "Your facebook ID: $id <br>";
    $postRequest = new FacebookRequest($sess, 'POST', '/me/feed', array('message' => 'My First Post using facebook sdk!'));
    $postResponse = $postRequest->execute();
    $posting = $postResponse->getGraphObject();
    echo $posting->getProperty('id');
  } else {
    echo "<a href='".$helper->getLoginUrl(array('email','user_about_me'))."'>Login with facebook</a>";
  }
} catch(FacebookRequestException $e) {
    echo "Error failed: " . $e->getCode() ;
}
?>