Post on a Facebook wall as Page, not as user

Question

Is it possible to post on a Facebook wall as application and not as user? As far as I understand an application is not a valid user for Facebook, but there are numerous comments about posting as Page and not as User or Application.

How can I do it using PHP Facebook API?

Answer 1

You need the publish_stream,manage_pages permissions. The code is something like:

<?php
// This code is just a snippet of the example.php script
// from the PHP-SDK <https://github.com/facebook/facebook-php-sdk/blob/master/examples/example.php>
require '../src/facebook.php';

// Create our Application instance (replace this with your appId and secret).
$facebook = new Facebook(array(
  'appId'  => 'app_id',
  'secret' => 'app_secret',
));

// Get User ID
$user = $facebook->getUser();

if ($user) {
  try {
    $page_id = 'page_id';
    $page_info = $facebook->api("/$page_id?fields=access_token");
    if( !empty($page_info['access_token']) ) {
        $args = array(
            'access_token'  => $page_info['access_token'],
            'message'       => "I'm a Page!"
        );
        $post_id = $facebook->api("/$page_id/feed","post",$args);
    } else {
        $permissions = $facebook->api("/me/permissions");
        if( !array_key_exists('publish_stream', $permissions['data'][0]) ||
            !array_key_exists('manage_pages', $permissions['data'][0])) {
            // We don't have one of the permissions
            // Alert the admin or ask for the permission!
            header( "Location: " . $facebook->getLoginUrl(array("scope" => "publish_stream, manage_pages")) );
        }

    }
  } catch (FacebookApiException $e) {
    error_log($e);
    $user = null;
  }
}

// Login or logout url will be needed depending on current user state.
if ($user) {
  $logoutUrl = $facebook->getLogoutUrl();
} else {
  $loginUrl = $facebook->getLoginUrl(array('scope'=>'manage_pages,publish_stream'));
}

// ... rest of your code
?>

I've written and in-depth tutorial about this: How To: Post On Facebook Page As Page Not As Admin User Using PHP-SDK

Answer 2

You must first have a user authorize via facebook connect, and request the manage_pages permission as a part of this request. You can use this permission to obtain a token and secret for the page in question. You then use those to authorize requests as opposed to the token/secret you received for the user.

Check out the "Page Login" section of this page for some additional info: http://developers.facebook.com/docs/authentication/