[Dovecot] How to use filters with the LDA?

[Peter Fern]

martin f krafft wrote:
> Hi,
>
> I am trying to deploy dovecot LDA and liking it so far. However,
> I need to pass the message through some filters before it's
> delivered to the user (e.g. spamc). I realise I can just set up
> a chain (postfix delivers to spamc, pipes to foo, pipes to bar,
> pipes to deliver), but there's no reliable error handling with that
> approach.
>   
I do this using postfix, dspam via LMTP and deliver, and it does indeed
have reliable error handling.
> Furthermore, I cannot seem to figure out whether sieve can pass
> messages through external filters, or how you'd do that.
>
> How do people approach this?
>   
Nope, unfortunately  sieve does not provide for piping to an external
program.
> What would be really sweet is an LDA plugin that can call arbitrary
> filters for each message it processes. Has something (obvious) like
> this been done?
>   
I don't believe this has been coded, but the new deliver uses sieve as a
plugin, so I don't see why this shouldn't be possible.  You could always
write one ;)