Subscribed event to send mail not working

[ruddhani]

I have implemented 02 routes from draft creation to admin validation steps. Now I want to add a event subscriber so that after draft creation is reached, an email will trigger.

I am adding the event to subscribedEvents as:

public static function getSubscribedEvents()
    {
        return array(
            'post_publication.draft_created.reached' => array(
                'handleDraftCreated',
            ),
        );
    }

But unfortunately the handleDraftCreated function never called:

public function handleDraftCreated(StepEvent $event)
    {
        echo "handleDraftCreated called";
    }

Anything I am missing here, need help, thanks in advance.