public function indexAction()
 {
     if (isset($_SESSION['auth']) && $_SESSION['auth']['permissions'] === 'superadmin') {
         header('content-type: application/json');
         header('Access-Control-Allow-Origin: *');
         header('Access-Control-Allow-Methods: GET');
         echo json_encode(ProfileModel::showLastUsers($this->pdo));
     } else {
         header('Location: /');
         exit;
     }
 }