public function CacheControlEventSubscriber::setHeaderCacheControl in HTTP Cache Control 8.2

Same name and namespace in other branches

1. 8 src/EventSubscriber/CacheControlEventSubscriber.php \Drupal\http_cache_control\EventSubscriber\CacheControlEventSubscriber::setHeaderCacheControl()

Set http cache control headers.

File

src/EventSubscriber/CacheControlEventSubscriber.php, line 33

Class

CacheControlEventSubscriber

Subscriber for adding http cache control headers.

Namespace

Drupal\http_cache_control\EventSubscriber

Code

public function setHeaderCacheControl(FilterResponseEvent $event) {
  $config = $this->configFactory
    ->get('http_cache_control.settings');
  $response = $event
    ->getResponse();
  if ($variation = $config
    ->get('cache.http.vary')) {
    $vary = $response
      ->getVary();
    foreach (array_map('trim', explode(',', $variation)) as $header) {
      $vary[] = $header;
    }
    if (!Settings::get('omit_vary_cookie')) {
      $vary[] = 'Cookie';
    }
    $response
      ->setVary(implode(',', $vary));
  }
  if (!$response
    ->isCacheable()) {
    return;
  }
  $ttl = $response
    ->getMaxAge();
  switch ($response
    ->getStatusCode()) {
    case 404:
      $ttl = $config
        ->get('cache.http.404_max_age', $ttl);
      break;
    case 302:
      $ttl = $config
        ->get('cache.http.302_max_age', $ttl);
      break;
    case 301:
      $ttl = $config
        ->get('cache.http.301_max_age', $ttl);
      break;
  }
  if ($ttl != $response
    ->getMaxAge()) {
    $response
      ->setClientTtl($ttl);
    $response
      ->setSharedMaxAge($ttl);
  }
  elseif ($ttl = $config
    ->get('cache.http.s_maxage')) {
    $response
      ->setSharedMaxAge($ttl);
  }
  if ($response
    ->getStatusCode() >= 500) {
    $response
      ->setSharedMaxAge($config
      ->get('cache.http.5xx_max_age'));
  }
  elseif ($response
    ->getStatusCode() < 400) {

    // Add stale-if-error directive.
    if ($seconds = $config
      ->get('cache.http.stale_if_error')) {
      $response->headers
        ->addCacheControlDirective('stale-if-error', $seconds);
    }

    // Add stale-while-revalidate directive.
    if ($seconds = $config
      ->get('cache.http.stale_while_revalidate')) {
      $response->headers
        ->addCacheControlDirective('stale-while-revalidate', $seconds);
    }

    // Surrogate Control
    $maxage = $config
      ->get('cache.surrogate.maxage');
    $nostore = $config
      ->get('cache.surrogate.nostore');
    if (!empty($maxage) || $nostore) {
      $value = $nostore ? [
        'no-store',
      ] : [];
      if (!empty($maxage)) {
        $value[] = 'max-age=' . $maxage;
      }
      $response->headers
        ->set('Surrogate-Control', implode(', ', $value));
    }
  }
}