private function generateArticleLinks(SitemapPopulateEvent $event, Issue $issue) { $articles = $issue->getArticles(); $journal = $issue->getJournal(); foreach ($articles as $article) { $event->getUrlContainer()->addUrl(new UrlConcrete($this->router->generate('ojs_article_page', ['slug' => $journal->getSlug(), 'issue_id' => $issue->getId(), 'article_id' => $article->getId()], true), new \DateTime(), UrlConcrete::CHANGEFREQ_WEEKLY, 1), 'journals-' . $journal->getSlug()); } return $event; }