public function publish(GenericEvent $event)
    {
        $legacyArticle = $event->getSubject();
        $arguments = $event->getArguments();

        if ($legacyArticle instanceof \Article) {
            $entry = $this->em
                ->getRepository('Newscoop\IngestPluginBundle\Entity\Feed\Entry')
                ->findOneByArticleId($legacyArticle->getArticleNumber());
            if ($entry !== null) {
                $entry->setPublished(new \DateTime($legacyArticle->getPublishDate()));
                $this->em->persist($entry);
                $this->em->flush();
            }
        }
    }