Question

I’m trying to do a script which takes the logged-in user – retrieves the list of friends and loops through these friends to get their friendlist. Meaning the users friends-of-friends. I’ve read somewhere that this isn’t possible, but if I log in to facebook.com with my user and browse one of my friends, I can easily see his friendlist? Can you help clarifying this?

My code:

    $friends = $facebook->api('/me/friends');

foreach ($friends["data"] as $friend) {

    try {
        $friendsfriends = $facebook->api('/'.$friend["id"].'/friends?fields=name,hometown,location,picture');
    } catch(Exception $e) {
        $friendsfriends = null;
    }

    print '<pre>';
    print var_dump($friendsfriends);
    print '</pre>';
}

Which casts some error saying I can’t view the users friends.

Answer 1

What you are looking to do is not possible. When a user has authorised and is using your application, the set of extended permissions (see Facebook Permissions) apply explicitly to that user. So if you’ve got extended permissions to read friend data, you can only get friend data relative to the current user – because those are the permissions you have and you don’t have valid access tokens, with respect to the friends, to go further. If you wanted to traverse further through the graph, those friends would have to have authorised your application and you would require an offline access token to get to their friend data.

There are a number of capabilities available on the main Facebook site that are not available via any the Facebook API. This can be frustrating, but you have to make do with the capabilities that are available.