How to: Check if User Has Certian Permission – Facebook API （通过facebook提供的php版本的SDK发送feed）

There are two three ways to check if the user has granted your application a specific Permission:

 

Using the Graph API

Now that Facebook added the permissions connection to the user object, you can easily check the user’s permission:

$permissions = $facebook->api("/me/permissions");
if( array_key_exists('publish_stream', $permissions['data'][0]) ) {
    // Permission is granted!
    // Do the related task
    $post_id = $facebook->api('/me/feed', 'post', array('message'=>'Hello World!'));
} else {
    // We don't have the permission
    // Alert the user or ask for the permission!
    header( "Location: " . $facebook->getLoginUrl(array("scope" => "publish_stream")) );
}

 

Using the FQL permissions table

You can query the permissions table to check if a certain permission (or set of permissions) is granted:

 

SELECT read_stream FROM permissions WHERE uid=me()

We will give two examples of how to query this table in:

• PHP:

   

  $perms = $facebook->api(array(
      "method"    => "fql.query",
      "query"        => "SELECT read_stream,offline_access,publish_stream FROM permissions WHERE uid=me()"
  ));
  echo "<ul>";
  foreach($perms[0] as $k=>$v) {
      echo "<li>";
      if($v === "1") {
          echo "<strong>$k</strong> permission is granted.";
      } else {
          echo "<strong>$k</strong> permission is not granted.";
      }
      echo "</li>";
  }

  Output:

  • read_stream permission is not granted.
  • offline_access permission is not granted.
  • publish_stream permission is granted.

• Javascript:

  FB.api({ method: 'fql.query', query: 'SELECT read_stream,offline_access,publish_stream FROM permissions WHERE uid=me()' }, function(resp) {
      for(var key in resp[0]) {
          if(resp[0][key] === "1")
              console.log(key+' is granted')
          else
              console.log(key+' is not granted')
      }
  });

  Back to top

---

 

Using the REST API users.hasAppPermission method

It is worth mentioning that the users.hasAppPermission is still working and can be called from the Facebook PHP-SDK like so:

$isGranted = $facebook->api(array(
    "method"    => "users.hasAppPermission",
    "ext_perm"   => "publish_stream",
    "uid"       => 579187142
));
if($isGranted === "1")
    echo "Permission granted!";

Please note that this call doesn’t require the uid parameter, if you have a valid user session.

Now we call the same function in Javascript:

FB.api({ method: 'users.hasAppPermission', ext_perm: 'publish_stream' }, function(resp) {
    if (resp === "1") {
        alert('Permission granted');
    } else {
        alert("Permission not granted");
    }
});

 

 

 

 

 

 

 

 

 

总结：项目当中，想通过facebook提供的php版本的SDK发送feed,应用的就是以下代码：

 

$permissions = $facebook->api("/me/permissions");
if( array_key_exists('publish_stream', $permissions['data'][0]) ) {
    // Permission is granted!
    // Do the related task
    $post_id = $facebook->api('/me/feed', 'post', array('message'=>'Hello World!'));
} else {
    // We don't have the permission
    // Alert the user or ask for the permission!
    header( "Location: " . $facebook->getLoginUrl(array("scope" => "publish_stream")) );
}