['onCoreException', 1] ]; } public function onCoreException(ExceptionEvent $event) { $request = $event->getRequest(); if ($request->isXmlHttpRequest()) { $exception = $event->getException(); if ($exception instanceof AuthenticationExpiredException) { $event->setResponse(new Response('Session expired', 403, ['Login-Required' => true])); } elseif ($exception instanceof AuthenticationException) { $event->setResponse(new Response('Authentication problem', 403, ['Login-Required' => true])); } elseif ($exception instanceof AccessDeniedException) { $event->setResponse(new Response('Access denied', 403, ['Login-Required' => true])); } } } }