如何使用特定标签向特定订阅者发送新闻

Question

我有订阅者的数据库，订阅了特定的标签和需要发送给订阅者的新新闻。我需要在Symfony 4上编写命令来做到这一点。我已经有这段代码了：

class SubscribeLauncherCommand extends ContainerAwareCommand
{
    protected static $defaultName = 'app:subscribe-launcher';
    private $mailer;
    protected $em;
    public function __construct(EntityManagerInterface $em, Swift_Mailer $mailer)
    {
        $this->mailer = $mailer;
        $this->em = $em;
        parent::__construct();
    }
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $news = $this->em->getRepository(News::class)->findBy(array(), array('date_created' => 'DESC'));
        $subscribers = $this->em->getRepository(NewsSubscribe::class)->findBy(array('confirmed' => true));
        $tags = $this->em->getRepository(Tag::class)->findAll();
        $first_new_date = $news[0]->getDateCreated();
        /** @var NewsSubscribe $subscribers */
        /** @var Swift_Message $message */
        foreach ($subscribers as $subscriber) {
            foreach ($news as $new)
            {
                if ($new->getDateCreated() < $first_new_date) {
                    $message = (new Swift_Message('Test Email'))
                        ->setFrom('[e-mail]')
                        ->setTo($subscriber->getEmail())
                        ->setBody(
                            'test',
                            'text/html');
                    $first_new_date = $new->getDateCreated();
                }
            }
        }
    }
}

但它不起作用。你能帮忙吗？

Answer 1

所以我认为订阅者有一个他们订阅的标签集合，新闻与标签相关。

如果是这种情况，您需要在循环中添加几个条件，例如：

 foreach ($subscribers as $subscriber) {
        $subscribedTags = $subscriber->getSubscribedTags();
        foreach ($news as $new)
        {
            if ($new->getDateCreated() < $first_new_date) {
                $relatedTag = $new->getTag();
                if(in_array($relatedTag, $subscribedTags)){ //Check if the user is subscribed to the particular tag of this news
                    ...Send the email...
                }
            }
        }
    }