mailman3 integration

[joergmschulz]

Mailing list management features are currently out of scope with stalwart.
There is a basic concept in - https://github.com/ewdurbin/stalwart-mailman , This only works for outdated versions, and it does not handle messages arriving from the outside (will get stuck in the virtual users created for each list),
A mailman3 integration would need to catch in for incoming smtp in the rcpt stage. Is it a good idea to resolve this with a sieve script that would be created via a mailman3 extension?

[mdecimus]

Is it a good idea to resolve this with a sieve script that would be created via a mailman3 extension?

I'm not familiar with mailman3 but using Sieve would only make sense if the message could be forwarded to mailman somehow.

[joergmschulz]

Mailman provides a lmtp process and stalwart can send messages perfectly to this process. The question would be how to define the sieve script to provide this forwarding ideally after spam and virus check

[mdecimus]

In that case you could create a routing strategy that delivers those messages to mailman3 over LMTP.

[joergmschulz]

done that, works for outgoing messages. For incoming messages, still a sieve script is necessary in the data stage. If mailman is supposed to serve special domains (list.mydomain.com) or domains without users, this works straightforward. So the mentioned plugin is not needed in this case - or better should be changed to automatically create the domains and sieve rules when the activity on mailman side is very dynamic.