Getting facebook page access token

index.php

<?php

$appId = '';
$appSecret = '';

// Do not change below this line

session_start();
require_once __DIR__ . '/Facebook/autoload.php';

$fb = new Facebook\Facebook([
  'app_id' => $appId,
  'app_secret' => $appSecret,
  'default_graph_version' => 'v2.5',
  ]);

$helper = $fb->getRedirectLoginHelper();

$accessToken = $_SESSION['accessToken'];

if (isset($_GET['logout'])) {
	$_SESSION['accessToken'] = '';
} else if (isset($_GET['login-callback'])) {
	try {
	  $accessToken = $helper->getAccessToken();
	} catch(Facebook\Exceptions\FacebookResponseException $e) {
	  // When Graph returns an error
	  echo 'Graph returned an error: ' . $e->getMessage();
	  exit;
	} catch(Facebook\Exceptions\FacebookSDKException $e) {
	  // When validation fails or other local issues
	  echo 'Facebook SDK returned an error: ' . $e->getMessage();
	  exit;
	}
	$_SESSION['accessToken'] = $accessToken->getValue();

}
if ($accessToken == '') {
	$permissions = ['email', 'manage_pages', 'read_page_mailboxes']; // optional
	$loginUrl = $helper->getLoginUrl('http://stage.telldus.se/facebook/?login-callback', $permissions);

	echo '<a href="' . $loginUrl . '">Log in with Facebook!</a>';
	die();

}

echo '<pre>';
$fb->setDefaultAccessToken($accessToken);

$response = $fb->get('/me');
$userNode = $response->getGraphUser();
echo 'Logged in as ' . $userNode->getName() . ' (' . $userNode->getId() . ")\n";
printf("Access token: %s\n\n", $accessToken);

$response = $fb->get('/' . $userNode->getId() . '/accounts');
$pd = $response->getDecodedBody();
foreach($pd['data'] as $p) {
	printf("Page %s\n  Id: %s\n  Access token: %s\n\n", $p['name'], $p['id'], $p['access_token']);
}

echo '<a href="?logout">Logout</a>';