<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Messenger\EventListener;
use Psr\Cache\CacheItemPoolInterface;
use Psr\Log\LoggerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Messenger\Event\WorkerRunningEvent;
use Symfony\Component\Messenger\Event\WorkerStartedEvent;
/**
* @author Ryan Weaver <ryan@symfonycasts.com>
*/
class StopWorkerOnRestartSignalListener implements EventSubscriberInterface
{
public const RESTART_REQUESTED_TIMESTAMP_KEY = 'workers.restart_requested_timestamp';
private $cachePool;
private $logger;
private $workerStartedAt;
public function __construct(CacheItemPoolInterface $cachePool, ?LoggerInterface $logger = null)
{
$this->cachePool = $cachePool;
$this->logger = $logger;
}
public function onWorkerStarted(): void
{
$this->workerStartedAt = microtime(true);
}
public function onWorkerRunning(WorkerRunningEvent $event): void
{
if ($this->shouldRestart()) {
$event->getWorker()->stop();
if (null !== $this->logger) {
$this->logger->info('Worker stopped because a restart was requested.');
}
}
}
public static function getSubscribedEvents()
{
return [
WorkerStartedEvent::class => 'onWorkerStarted',
WorkerRunningEvent::class => 'onWorkerRunning',
];
}
private function shouldRestart(): bool
{
$cacheItem = $this->cachePool->getItem(self::RESTART_REQUESTED_TIMESTAMP_KEY);
if (!$cacheItem->isHit()) {
// no restart has ever been scheduled
return false;
}
return $this->workerStartedAt < $cacheItem->get();
}
}