We are running now our own email server, and it works well for outgoing emails with Discourse. So now I am looking into receiving emails to reply to posts.
There is this POP3 polling, but our Dovecot has POP3 disabled, using IMAP only. There are settings for IMAP polling intervals, but none to enable IMAP polling, defining host, port, credentials etc, like for POP3 polling. Does IMAP polling just share the settings for POP3 polling, and is it then possible to effectively disable POP3 polling by setting its interval to 0 minutes or something like that?
The question has been asked before, but no answer: Is there a way to use IMAP instead of POP3 for replies by email?
I do not intend to run a second Postfix as Discourse mail-receiver container, and it wouldn’t work anyway as of port 25 use on the host.
Best would be, of course, to use the Discourse email-in API directly with the Postfix we have. It does not even look that complex: mail-receiver/lib/mail_receiver/discourse_mail_receiver.rb at main · discourse/mail-receiver · GitHub
- POST request with system user, API key and sender email as form data.
- But the sanity checks are more complicated on first view: mail-receiver/lib/mail_receiver/fast_rejection.rb at main · discourse/mail-receiver · GitHub
- I might be able to implement this as shell script to conditionally (receiver email) pipe into, but keeping that up-to-date and functional is probably not practical/reasonable.
So IMAP-only polling would be my preferred solution, I hope this is possble.
EDIT: Or we just install Ruby runtime and copy lib and executables of the mail receiver and fast reject in place on the host, like the Dockerfile does, and invoke it from our Postfix via transport_maps the same way: mail-receiver/Dockerfile at main · discourse/mail-receiver · GitHub
Has anyone tried this?