facebook getLogoutUrl returns a URL with access_token=0, when clicked redirects to Facebook user's home page

Question

I'm integrating Facebook with my site and I've added a Logout button whose URL is taken from:

$facebook->getLogoutUrl(array('next' => 'http://mydomain.com/logout.php'));

The problem is that logout.php is never called. Instead, on click of the Logout button, it redirects to the logged-in user's Facebook home page. It doesn't log the user out of Facebook, and it doesn't call my next URL.

I noticed that the URL generated by getLogoutURL() looks like:

https://www.facebook.com/logout.php?next=http://mydomain.com/logout.php&access_token=0

Notice there is an access_token=0. Should that value not be zero? That's the only thing I can think of that might be causing the problem.

I've already set my FB app's Site URL to http://mydomain.com. While testing locally, I've also edited my hosts file. I've also googled a lot and I haven't found a solution. The only one that worked was adding an onclick to my logout button using FB.logout(). But I would need to use PHP.

Any ideas as to why the logout URL is not working?

Answer 1

Okay, I've solved this by creating my own logout URL and adding an access token

$logoutUrl = 'https://www.facebook.com/logout.php?next=http://mydomain.com/logout.php&access_token=' . $facebook->getAccessToken();

Answer 2

I hope you've found a solution! But if not, try with the following code. It worked for me!

$facebook->getLogoutUrl(array('next' =>'http://example.com/logout.php', 'access_token'=>$facebook->getAccessToken()));`

If you check out the official documentation you'll see it says nothing about setting the access token option in the parameter array but it really works! Good Luck!!

Answer 3

The problem is that you need to call getAccessToken BEFORE ask for the logout url.

$facebook->getAccessToken();

Don't need to call it inside as a getLogoutURL parameter. Just call it one line before:

$user = $facebook->getUser();
$access_token = $facebook->getAccessToken();
$logoutUrl = $facebook->getLogoutUrl();

Answer 4

I had the same problem too (access_token=0), but then I realized I was clearing Facebook cookies before calling getLogoutURL(). If you get the getLogoutURL() result first, access_token should not be zero.