FEATURE: Handle OAuth for MS Mails

[markusguenther]

Microsoft permanently disabled basic auth for sending emails and as many companies using MS for sending mails, we should also take care of that. The topic already came up in the symfony mailer repository.

symfony/symfony#48888

[Benjamin-K]

There is already a Neos Package for this: https://github.com/code-q-web-factory/OAuthSymfonyMailer (also so the slack discussion here: https://neos-project.slack.com/archives/C050C9FKB/p1756997662441629). Maybe Code Q can create a PR?

[markusguenther]

Yes I know but I would see that as part of this package, to not have a package zoo...

[Benjamin-K]

I think so, too. And in the Slack discussion, Felix Gradinaru already mentioned, that he would like to have this in here, too...

[olimination]

With Symfony v7.4 they have released a 3rd Party Mailer Transport called "Microsoft Graph" which allows sending mails via Microsoft's Graph API. I don't understand the details but I assume in Neos we simply can configure this MS Graph DSN and make sure that Symfony Mailer component 7.4 and the "symfony/microsoft-graph-mailer" is loaded as dependency, then it should work so far. I could not test it yet, but maybe soon I have some real use case where I can test it.

What do you think?

Check out these links too for more details:

• Symfony PR: [Mailer] Add MicrosoftGraph API Transport symfony/symfony#61290
• Symfony Mailer docs: https://symfony.com/doc/7.4/mailer.html#installation
• Symfony Mailer README: https://github.com/symfony/symfony/blob/7.4/src/Symfony/Component/Mailer/Bridge/MicrosoftGraph/README.md

[olimination]

I was able to make a first test and analysis.

With the first run I have faced the following exception:

The "microsoftgraph+api" scheme is not supported.

A deeper look into the code I have seen that the "Microsoft Graph API" transport is not included as a default TransportFactory in the list: https://github.com/symfony/symfony/blob/7.4/src/Symfony/Component/Mailer/Transport.php#L55

I have adapted the MailerService to initialize the Transport manually and to load the missing MicrosoftGraphTransportFactory class in to the factories list:

$httpClient = HttpClient::create();
$transportFactories = iterator_to_array(Transport::getDefaultFactories());
$transportFactories[] = new MicrosoftGraphTransportFactory(client: $httpClient);
$transportFactory = new Transport($transportFactories);
$transport = $transportFactory->fromString($this->mailerConfiguration['dsn']);
return new Mailer($transport);

Then it worked :-)

I think for further steps we would need to think about how the MailerService can handle dynamically other TransportFactory classes.

A first step could be to introduce an interface for the MailerService e.g. MailerServiceInterface. This would allow other users to use a custom implementation if needed. Currently we need to implement a custom Action to use another a custom MailerService.

Also there is the topic about the HttpClient. Currently it depends on Symfony's HttpClientInterface, maybe there would be a better integration with the Neos/Flow ecosystem using PSR18, etc.

Another thought is to ask the Symfony Mailer guys to add the MicrosoftGraphTransportFactory to the default list, don't know if this would make sense too.

Should we open a separate issue for the general topic of handling other 3rd party TransportFactory classes properly? Because this issue is about "OAuth2 via SMTP XOAuth2 with MS365".