By Sam Moore, 12 March, 2021

services:
  hello_world.salutation:
    class: Drupal\hello_world\HelloWorldSalutation
    arguments: ['@config.factory', '@event_dispatcher']
  hello_world.redirect_subscriber:
    class: \Drupal\hello_world\EventSubscriber\HelloWorldRedirectSubscriber
    arguments: ['@current_user', '@current_route_match']
    tags:
      - { name: event_subscriber }