In this tutorial you'll learn how to make use of the event object that are passed to you and the methods that come with it. You'll also learn how to use dependency injection to add a logger for our class and add this argument to our services YAML file.
Note: Drupal 9 now requires Symfony 4.4. The class mentioned at 0:15,
\Symfony\Component\HttpKernel\Event\GetResponseEvent, is deprecated. Use