Mailer stop setting on fly SMTP due to usage of Symfony mailer

Laravel Version: 9.11
PHP Version: 8.0.1
Database Driver & Version: MySQl
Description:
In the early versions of Laravel (6-8) I was able to set the on the fly SMTP configuration for the mail in the queue using swift mailer. But now, due to the removal of Swift mailer, and addition symfony mailer, I am unable to set the on custom STMP on the fly for the users.

The method (Mailer::setSymfonyTransport(TransportInterface $transport);) works fine if the mail is not sent in the queue. However, it stopped working with the queue.

It directly takes the default SMTP.

Steps To Reproduce:
To reproduce the error, please follow below steps

1. In web.php, in the welcome route, create new SMTP transport using MailManager::createSymfonyTransport($config);
2. set new transport using Mailer::setSymfonyTransport(TransportInterface $transport);
3. Create new mail, which implements ShouldQueue
4. Try to send the mail with the queue functionality.

https://github.com/PareshP-RSW/bug-report
Here I have created the repo. to regenerate the issue.

The repo contains two mail configuration, you can see it in the .env.example (just to show you. In real life it will be base on tenants.So there could be 1000 different SMTP)
Enter smtp config for both the settings.
migrate the DB
Enable the queue in .env
This project has two mailer routes. mail-with-queue and mail-without-queue
mail-with-queue will set the custom config first and then it will put the mail in queue
mail-without-queue will set the custom config first and then it will directly send the email
Issue

=> It set the custom SMTP while sending the mail directly.
=> It uses the default SMTP when sending the mail using queue. (Setting up custom config does not work)

Expected behaviour
=> Custom SMTP should work on Queue also.

Thanks.

[rodrigopedra]

Just as a clarification, as I don´t understand very clear:

• Sending the email synchronously, e.g. directly with the ->send(...) method works with the changed SMTP
• Sending the email asynchronously, e.g. queued with the ->queue(...) method DOES NOT work with the changed SMTP

Is that correct?

Well, if so, I am surprised to learn it did use a changed mailer driver on previous versions. Wouldn't you using the sync driver then?

If you are using a queue driver other than the sync, the queued mail is supposed to be sent asynchronously, in other words a pending job will be enqueued, and a queue worker will pick that job up and send it.

The queue worker is a different PHP process than the web process, so Laravel will bootstrap itself by scratch thus reading configuration again, your custom mailer configurations will be lost as this separate process is not aware of the changes done in the web process.

If you want to have the custom SMTP settings saved along the queued mail, you could:

• Accept the mailer config array on the Mailable constructor
• Change the SMTP in the Mailable build method,

Like this:

<?php

namespace App\Mail;

use Illuminate\Bus\Queueable;
use Illuminate\Mail\Mailable;
use Illuminate\Queue\SerializesModels;
use Illuminate\Support\Facades\Mail;

class EmailWithQueue extends Mailable
{
    use Queueable;
    use SerializesModels;

    public function __construct(
        public array $mailerConfig,
    ) {
    }

    public function build()
    {
        $customConfig = Mail::createSymfonyTransport($this->mailerConfig);

        Mail::setSymfonyTransport($customConfig);

        return $this->markdown('email.withQueue');
    }
}

And dispatch it like this:

<?php

use App\Mail\EmailWithQueue;
use Illuminate\Support\Facades\Mail;
use Illuminate\Support\Facades\Route;

Route::get('/mail-without-queue', function () {
    // do not use the env() helper outside of config files
    // when config are cached the env() helper will only
    // return the default value, which is usually null,
    // thus rendering unexpected results. This is outlined
    // in the docs: https://laravel.com/docs/9.x/configuration#configuration-caching
    // 
    // Instead, define a new custom mailer configuration
    // in your ./config/mail.php file and use it here
    $mail = new EmailWithQueue(config('mail.mailers.my-custom-mailer'));

    Mail::to('laravelbugtest@mailinator.com')->send($mail);
});

If it i not working both when sending synchronously (->send(...)) and asynchronously (->queue(...)), than it is really unexpected behavior, and please apologize me for my misunderstanding.

PS: out of the box Laravel supports also the null queue driver, which in theory is not a asynchronous driver. But as the null queue driver will discard every job sent to it, it actually doesn't matter how it would handle your custom config.

Just as a clarification, as I don´t understand very clear:

• Sending the email synchronously, e.g. directly with the ->send(...) method works with the changed SMTP
• Sending the email asynchronously, e.g. queued with the ->queue(...) method DOES NOT work with the changed SMTP

Is that correct?

Yes I did mean the same. And thank you for the reply on the same.

I have not tried the method which you have described here. I'll try and come back again.

@rodrigopedra
Look likes the method which you have provided me is working fine on the test project for now.
I'll check the same method on my original project which has more than 5000 different dynamic email configs.
Thanks mate for the quick solution. Thanks man

[driesvints]

Thanks @rodrigopedra