Symfony 6 mail sender DSN using SMTP cannot send mail

Question

I'm trying to use Symfony 6 Mailer with different SMTP servers, but none of them work.

The message was queued but not sent. I've tried troubleshooting firewall or port issues from different servers.

There are no log messages or exceptions, so I'm confused.

Here are some DSNs I've tried:

MAILER_DSN="smtp://email%40example.com:[email protected]:587?encryption=tls"
MAILER_DSN="smtp://[email protected]:[email protected]:587?encryption=tls"
MAILER_DSN="smtp://[email protected]:[email protected]:587"

I actually tried many DSN combinations with/without encryption. I suspect the problem is in the DSN string because if I try the wrong host or password the effect is the same.

This is a long-standing problem that I couldn't solve for a long time.

This is the sending code:

use Symfony\Component\Mime\Email;

$email = (new Email())
        ->from($this->parameterBag->get('app.message.email_from'))
        ->to($to)
        ->subject($subject)
        ->text($text)
        ->html($text);

$sentMessage = $this->mailer->send($email);

mailer.yamlContent:

framework:
    mailer:
        dsn: '%env(MAILER_DSN)%'

and messenger.yaml Content:

framework:
    messenger:
        failure_transport: failed

        transports:
            # https://symfony.com/doc/current/messenger.html#transport-configuration
            async:
                dsn: '%env(MESSENGER_TRANSPORT_DSN)%'
                options:
                    use_notify: true
                    check_delayed_interval: 60000
                retry_strategy:
                    max_retries: 3
                    multiplier: 2
            failed: 'doctrine://default?queue_name=failed'
            # sync: 'sync://'

        routing:
            Symfony\Component\Mailer\Messenger\SendEmailMessage: async
            Symfony\Component\Notifier\Message\ChatMessage: async
            Symfony\Component\Notifier\Message\SmsMessage: async

            # Route your messages to the transports
            # 'App\Message\YourMessage': async

Answer 1

Based on your current messenger configuration, the email is not sent directly, but only when messenger:consume is called.

This is because Messenger is queuing the email (or other message like a text message) instead of sending it immediately.

You can learn more about the Message component here a>, but if you want to ignore it for now, just send emails synchronously by modifying the transport configuration.

framework:
    messenger:
        transports:
            async: 'sync://'
        routing:
            Symfony\Component\Mailer\Messenger\SendEmailMessage: async
            Symfony\Component\Notifier\Message\ChatMessage: async
            Symfony\Component\Notifier\Message\SmsMessage: async

            # Route your messages to the transports
            # 'App\Message\YourMessage': async