Can't logout on my site when using getLogoutUrl() - php

Question

I've got 2 tabs open in Firefox, one is my website and the other is Facebook. Without the app authorised I get a login link, I click this which I am then prompted to auth the app which I do so.
I've now got on screen the logout URL provided by getLogoutUrl() - when I click this it redirects back to my site which I am happy with however it is still classing me as logged in. If I refresh the other tab with Facebook on I am now logged out. It seems there's some hangover on the session??
<?php
require_once("fb/facebook.php");
$config = array();
$config['appId'] = '...';
$config['secret'] = '...';
$config['fileUpload'] = false; // optional
$facebook = new Facebook($config);
$user_id = $facebook->getUser();
if($user_id) {
//Got an ID - Facebook says we're logged in
try {
$user_profile = $facebook->api('/me','GET');
echo "<img src=\"http://graph.facebook.com/".$user_profile['username']."/picture\">" . $user_profile['name']."";
$logout_url = $facebook->getLogoutUrl();
echo "Logout<br><br><br>";
}
catch(FacebookApiException $e) {
$login_url = $facebook->getLoginUrl();
echo 'Please login.';
error_log($e->getType());
error_log($e->getMessage());
}
}
else {
// Not logged in - give URL to login
$login_url = $facebook->getLoginUrl();
echo 'Please login.';
}
?>

Answer 1

You need to destroy the session.
$config = array();
$config['appId'] = 'xxxx';
$config['secret'] = 'xxxxx';
$facebook = new Facebook($config);
if(isset($_GET['act']) && $_GET['act'] == "logout") {
$facebook->destroySession();
}
$user = $facebook->getUser();
echo $user;
if ($user) {
try {
// Proceed knowing you have a logged in user who's authenticated.
$user_profile = $facebook->api('/me');
} catch (FacebookApiException $e) {
echo '<pre>'.htmlspecialchars(print_r($e, true)).'</pre>';
$user = null;
}
echo "<pre>";
print_r($user_profile);
echo "</pre>";
$logout = $facebook->getLogoutUrl();
//echo $logout;
echo "<a href='test.php?act=logout'>Logout</a>";
} else {
$login = $facebook->getLoginUrl(array("scope"=>"email","display"=>"popup","redirect_uri"=>"http://domain.com/test.php"));
echo "<a href='".$login."'>Login</a>";
}