function Fast404ExceptionHtmlSubscriber::onConfigSave
Invalidates 4xx-response cache tag if fast 404 config is changed.
Parameters
\Drupal\Core\Config\ConfigCrudEvent $event: The configuration event.
File
- 
              core/lib/ Drupal/ Core/ EventSubscriber/ Fast404ExceptionHtmlSubscriber.php, line 114 
Class
- Fast404ExceptionHtmlSubscriber
- High-performance 404 exception subscriber.
Namespace
Drupal\Core\EventSubscriberCode
public function onConfigSave(ConfigCrudEvent $event) : void {
  $saved_config = $event->getConfig();
  if ($saved_config->getName() === 'system.performance' && $event->isChanged('fast_404')) {
    $this->cacheTagsInvalidator
      ->invalidateTags([
      '4xx-response',
    ]);
  }
}Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.
