Context

Dovecot supports Lua. One use case is to extend its authentication options.

DMS currently does not include dovecot-lua.

Description

There is a dovecot-lua package available in Dovecot's deb repositories which are used to create the DMS image. Include this when building the image. The current version depends on Lua 5.3, which should be included as well.

Alternatives

Currently I patch Lua support into the docker-mailserver container upon initial startup (through user-patches.sh). I would like this to be included by default.

Applicable Users

Any users who use an authentication backend that does not fit in any other category. One example from my use case is HTTP basic authentication against Nextcloud (DAV), over HTTPS of course.

Are you going to implement it?

Yes, because I know the probability of someone else doing it is low and I can learn from it.

What are you going to contribute?

I'll try to make a pull request for this later. It should not be too difficult considering that nothing new needs to be developed. It just needs to be enabled.

So:

• Enable Dovecot Lua support (include dovecot-lua and dependencies).
• Write some light documentation. I don't think it is necessary to create new environment variables to compose the container. Lua-based authentication is an advanced topic. To use it, it would be best to rely on Dovecot configuration overrides. I'll add a usage example in the documentation.