TypeError: Drupal\drimage\Controller\DrImageController::image(): Argument #4 ($fid) must be of type int, string given

iwc_id and format are not optional parameters because they don't have a default value in the route definition. That means that they will never be passed as NULL to the controller method. This and the fact that we're adding integer validation on the route level to the width, height and fid route parameters means we can tighten a lot of parameter types in the controller methods and remove some custom validation.

Seems fine to me, you can merge this.

Automatically closed - issue fixed for 2 weeks with no activity.