gistfile1.php

// Create a state token to prevent request forgery.
// Store it in the session for later validation.
$state = md5(rand());
$app['session']->set('state', $state);
// Set the client ID, token state, and application name in the HTML while
// serving it.
return $app['twig']->render('index.html', array(
    'CLIENT_ID' => CLIENT_ID,
    'STATE' => $state,
    'APPLICATION_NAME' => APPLICATION_NAME
));