Re: set up Gnus to work with a remote system mailserver (with Dovecot?)

[Christian Barthel <bch@online.de>]

On Thursday, April 07, 2022, Emanuel Berg wrote:

> Anyone knows to setup Gnus to work with a remote system mailserver?
> I've heard it is IMAP and you are supposed to do accomplish this with
> something called Dovecot. [..]

nnimap is the way to go, see (info "(gnus) Using IMAP")

As far as I remember, the system you’re referring to does not expose 
Dovecot on a TCP port nor does it run Dovecot as a daemon.  In this
case, you can use the Dovecot imap binary.  The configuration should be
something like this:

--8<---------------cut here---------------start------------->8---
(setq gnus-select-method
  '(nnimap "Mail"
   (nnimap-stream shell)
   (nnimap-shell-program
      "ssh user@host /usr/local/libexec/dovecot/imap -o
      mail_location=maildir:~/Maildir/:LAYOUT=fs")))
--8<---------------cut here---------------end--------------->8---

(remove the “ssh user@host” if you’re working locally)

So, instead of talking with an IMAP Service on a network socket, it
executes the shell command and reads mails from there (stdin/stdout).
Make sure to setup ~/Maildir/ i.e. your incoming mail must be directed
into the ~/Maildir folder.

To redirect your incoming mail to fdm(1), you have to setup the
“.forward” file in your home directory:

--8<---------------cut here---------------start------------->8---
# cat ~/.forward
|/usr/local/bin/fdm -m -a stdin fetch
--8<---------------cut here---------------end--------------->8---

With fdm(1), something like this should work:

--8<---------------cut here---------------start------------->8---
# cat ~/.fdm.conf
action "inbox" maildir "/home/username/Maildir/"
match all action "inbox"
--8<---------------cut here---------------end--------------->8---

And then, you have to setup SMTP to send emails.


Some additional pointers:
https://github.com/nicm/fdm/blob/master/MANUAL#L730
https://dovecot.org/pipermail/dovecot/2009-February/037682.html
https://ding.gnus.narkive.com/8JpLY6yI/how-to-debug-nnimap-stream-shell
   (haven’t used that but that seems helpful for debugging)
-- 
Christian Barthel