[Drupal] Service dependency injection in a service type class

The code

services:
  my_module.event_subscriber:
    # Your service class
    class: Drupal\my_module\Entity\EventSubscriber\MyModuleSubscriber

    # Add your services to load here in the array
    arguments: ['@current_user']

    tags:
      # For this example, I am making an event subscriber class
      - { name: event_subscriber }

currentUser = $current_user;
  }

  static function getSubscribedEvents() {
    // Stuff related to events subscribing in Drupal
    $events[KernelEvents::REQUEST][] = ['kernel_request'];
    return $events;
  }

  /**
   * @param GetResponseEvent $event
   */
  public function kernel_request(Event $event) {
    // Do stuff here, using $this->currentUser
  }

}

Additional Information

• Declare the services your class will use in the .services.yml file of your module.
• Unlike plugin type class service dependency injection, there is no create method to define the needed services.
• The __construct signature needs to respect the declared arguments from the .services.yml file.
• Originally made and tested on Drupal 8.2.x.
• A convenient list of core services can be found here: https://api.drupal.org/api/drupal/core%21core.services.yml/8.2.x (don’t forget to select the Drupal version if you are not on 8.2.x).
• If you are curious about event subscribing in the Drupal world, please check this article: [Drupal] Create an event subscriber.