Symfony 3: add eventlistener by configuration

After triing arround to implement eventhandling in Symfony3 and I came up with a following solution.

Given: There is a event "thumbnail.finedata.created".

You have a listenerclass :
"Mittax\MediaConverterBundle\Event\Listener\Thumbnail\FineDataCreated"

And a method : onFineDataCreated() which takes the event.

In Symfony 3 there is a simple way to configure the eventlistener in default config.yml without to register the event in custom code.

The eventlistener is simply a tagged service. So Symfony knows it's event listeners by configuration.



Step 1:

This yaml snippet can be placed in a file "custom_events.yml" in app/config

Step 2: 

Import the new file in app/config.yml after service.yml

That`s it.

Now you can check your event with
php bin/console debug:event-dispatcher <your eventname>

Thx to mablae for this tut.