How tout use kernel.terminate Event in a Service

Question

I do a service that run an heavy task, this service is call in a Controller. To avoid a too long page loading, I want return the HTTP Response and run the heavy task after.

I've read we can use kernel.terminate event to do it, but I don't understand how to use it.

For the moment I try to do a Listener on KernelEvent:TERMINATE, but I don't know how to filter, for the Listener only execute the job on the good page...

Is it possible to add a function to execute on when the Event is trigger ? Then in my controller I juste use the function to add my action, and Symfony execute it later.

Thanks for your help.

Answer 1

Finally, I've find how to do it, I use the EventDispatcher in my Service and I connecting a Listener here a PHP Closure: http://symfony.com/doc/current/components/event_dispatcher.html#connecting-listeners

use Symfony\Component\EventDispatcher\Event;
use Symfony\Component\EventDispatcher\EventDispatcherInterface;
use Symfony\Component\HttpKernel\KernelEvents;

class MyService
{
  private $eventDispatcher;

  public function __construct(TokenGenerator $tokenGenerator, EventDispatcherInterface $eventDispatcher)
  {
   $this->tokenGenerator = $tokenGenerator;
   $this->eventDispatcher = $eventDispatcher;
  }

  public function createJob($query)
 {
    // Create a job token
    $token = $this->tokenGenerator->generateToken();

    // Add the job in database
    $job = new Job();
    $job->setName($token);
    $job->setQuery($query);

    // Persist the job in database
    $this->em->persist($job);
    $this->em->flush();

    // Call an event, to process the job in background
    $this->eventDispatcher->addListener(KernelEvents::TERMINATE, function (Event $event) use ($job) {
        // Launch the job
        $this->launchJob($job);
    });

    return $job;
 }