Gives 500th after sending a mail via rebbit, where can it stink?

Question

symfony

Controller:

<?php

namespace MailerBundle\Controller;

use MailerBundle\Entity\EmailHandler\EmailReceiver;
use MailerBundle\Entity\EmailHandler\EmailSender;
use MailerBundle\Sender\AbstractSender;
use MailerBundle\Entity\Notification;
use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpFoundation\Request;

class EmailController extends Controller
{
    /**
     * @var AbstractSender
     */
    private $sender;

    /**
     * EmailController constructor.
     * @param AbstractSender $sender
     * @param ContainerInterface $container
     */
    public function __construct
    (
        AbstractSender $sender,
        ContainerInterface $container
    )
    {
        $this->sender = $sender;
        $this->container = $container;
    }

    /**
     * @return \Symfony\Component\HttpFoundation\Response
     */
    public function indexAction()
    {
        return $this->render('MailerBundle:Email:index.html.twig');
    }

    /**
     * @param Request $request
     * @return \Symfony\Component\HttpFoundation\Response
     */
    public function sendAction(Request $request)
    {
        $notification = new Notification();
        $user = $this->get('security.token_storage')->getToken()->getUser();
        $notification->setBody($request->request->get('subject'), $user);
        $notification->setSubject($request->request->get('body'));
        $notification->setTo($request->request->get('to'));

        $data = $notification->toJson($this->sender->getMail());

        try {
            $amqpSender = new EmailSender();
            $message = $amqpSender->send($data);

            $receiver = new EmailReceiver($this->sender);
            // echo "<pre>";
            // print_r($message); exit;
            $receiver->receive($message);
        } catch (\Exception $ex) {
            return $this->render('MailerBundle:Email:error.html.twig', [
                'error' => $ex->getMessage()
            ]);
        }

        return $this->render('MailerBundle:Email:success.html.twig');
    }
}

rebbit sender:

<?php

namespace MailerBundle\Entity\EmailHandler;

use PhpAmqpLib\Connection\AMQPStreamConnection;
use PhpAmqpLib\Message\AMQPMessage;

class EmailSender extends AMQPHandler
{
    /**
     * @var AMQPStreamConnection
     */
    private $connection;

    /**
     * EmailSender constructor.
     */
    public function __construct()
    {
        $this->connection = $this->getConnection();
    }

    /**
     * @param $message
     * @return AMQPMessage
     */
    public function send($message)
    {
        $message = new AMQPMessage($message, ['delivery_mode' => 2]);
        $this->connection->basic_publish($message, '', 'email_queue');

        return $message;
    }
}

Recipient:

<?php

namespace MailerBundle\Entity\EmailHandler;

use MailerBundle\Sender\MailSender;
use PhpAmqpLib\Connection\AMQPStreamConnection;
use PhpAmqpLib\Message\AMQPMessage;

class EmailReceiver extends AMQPHandler
{
    /**
     * @var AMQPStreamConnection $connection
     */
    private $connection;

    /**
     * @var MailSender $sender
     */
    private $sender;

    /**
     * EmailReceiver constructor.
     * @param MailSender $sender
     */
    public function __construct(MailSender $sender)
    {
        $this->connection = $this->getConnection();
        $this->sender = $sender;
    }

    /**
     * @param AMQPMessage $message
     * @return AMQPMessage $message
     */
    public function receive(AMQPMessage $message)
    {
        $callback = function() use ($message)
        {
            $data = json_decode($message->body, true);
            $this->sender->send($data);
        };

        $this->connection->basic_qos(null, 1, null);
        $this->connection->basic_consume('email_queue', '', false, false, false, false, $callback);

        while(count($this->connection->callbacks)) {
            $this->connection->wait();
        }

        return $message;
    }
}

and a class for sending a letter:

<?php

namespace MailerBundle\Sender;

class MailSender extends AbstractSender
{
    /**
     * @var \Swift_Mailer
     */
    protected $transport;

    /**
     * @var string
     */
    private $userMail;

    /**
     * EmailSender constructor.
     * @param \Swift_Mailer $mailer
     * @param $name
     * @param $password
     */
    public function __construct(
        \Swift_Mailer $mailer,
        $name,
        $password
    )
    {
        $this->userMail = $name;
        $transport = \Swift_SmtpTransport::newInstance("smtp.gmail.com", 465, "ssl")
            ->setUsername($name)
            ->setPassword($password);

        $this->transport = $mailer::newInstance($transport);
    }

    /**
     * @return string
     */
    public function getMail()
    {
        return $this->userMail;
    }

    /**
     * @param array $notification
     * @return null
     */
    public function send($notification)
    {
        $message = \Swift_Message::newInstance($notification['subject'])
            ->setFrom([$notification['from']])
            ->setTo([$notification['to']])
            ->setBody($notification['body']);

        $this->transport->send($message);
    }
}

+ even when I send via gimail to i.ua, it doesn’t send,
+ maybe someone wrote tests for the swiftmailer with working mocks, can you share?