protected function file($file, $root)
{
$contents = file_get_contents($root . DIRECTORY_SEPARATOR . $file);
$response = response($contents, 200, ['Content-Type' => $this->getFileContentType($file)]);
// Browser will cache files for 1 year.
$secondsInYear = 60 * 60 * 24 * 365;
$response->setSharedMaxAge($secondsInYear);
$response->setMaxAge($secondsInYear);
$response->setExpires(new DateTime('+1 year'));
return $response;
}