Symfony\Component\HttpFoundation\BinaryFileResponse::hasValidIfRangeHeader PHP Method

    private function hasValidIfRangeHeader($header)
    {
        if ($this->getEtag() === $header) {
            return true;
        }
        if (null === ($lastModified = $this->getLastModified())) {
            return false;
        }
        return $lastModified->format('D, d M Y H:i:s') . ' GMT' === $header;
    }