I want to create custom events called user_logged so that i can attach my listeners to those events.

I want to execute few functions whenever user has logged in.

Create a class which extends Symfony\Component\EventDispatcher\Event.

Then, use the event dispatcher service to dispatch the event:

$eventDispatcher = $container->get('event_dispatcher');
$eventDispatcher->dispatch('custom.event.identifier', $event);

You can register your event listener service like so:

tags:
    - { name: kernel.event_listener, event: custom.event.identifier, method: onCustomEvent }

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