protected function isFreshEnough(Request $request, Response $entry) { if (!$entry->isFresh()) { return $this->lock($request, $entry); } if ($this->options['allow_revalidate'] && null !== ($maxAge = $request->headers->getCacheControlDirective('max-age'))) { return $maxAge > 0 && $maxAge >= $entry->getAge(); } return true; }