dovecot - Mar 2015 - Configuring Shared Mailbox Dictionaries

Hello, list!

I am in the midst of configuring a new Dovecot IMAP server, and I'm 
preparing to setup shard mailboxes as part of the ocnfiguration. In 
order to get these setup the way I want, I've figured out that I'm going
to have to setup an acl_shared_dict. This is where things start to get 
confusing for me, as I have had difficulty finding thorough explanations 
of dictionary configuration.

My primary concern is that all my user details are stored in a sqlite 
database in which the '%n' and '%d' components of username/email
addresses are stored in separate columns. The SQL dictionary example in 
the Shared Mailboxes document 
[http://wiki2.dovecot.org/SharedMailboxes/Shared] assumes that the 
username is stored as a singular '%n@%d' key. In my authdb lookups, I 
use sqlite syntax to concatenate the '%n' and '%d' columns
around a '@'
character to find the user. Is it possible to implement an 
acl_shared_dict in some similar fashion?

My second question, which is completely unrelated and more out of morbid 
curiosity than anything (although it could affect my configuration 
decisions) is that I noticed every dictionary which shows up in the 
documentation has a "pattern" field. In the case of the
acl_shared_dict
example, the pattern is 'shared/shared-boxes/user/$to/$from'. I
couldn't
figure out by studying the example where this value was derived from, or 
indeed where it is derived from in any example dictionaries which are 
documented. Can anyone explain the meaning of the "pattern" field and 
what exactly its value means?

Thanks in advance for all your helpful answers! :)

After doing some digging through old mailing list threads, I fonud the 
following information on the 'path' directive for dicts.

http://www.dovecot.org/list/dovecot/2009-April/038922.html

It looks like paths are hard coded per plugin, and you simply select one 
of the hard coded paths (this is what I gathered from the thread, I have 
not verified the accuracy of this).

After taking a romp through the Dovecot source, I was able to gather 
that as far as I can tell, the lvalue of anything inside of the fields{} 
block will be evaluated as a SQL expression, unless the expression 
includes characters '/' or '\\'. So in my case, the following 
configuration will *theoretically* meet my needs.

map {
   pattern = shared/shared-boxes/user/$to/$from
   table = mailbox_user_map
   value_field = mailbox_user
   fields {
    mailbox_user||'@'||mailbox_domain = $from
    user_name||'@'||user_domain = $to
   }
}

This is untested though, and I have almost certainly overlooked some 
devilish detail. Will report back further once I have time to test.

On 2015-03-13 05:48, james at lottspot.com wrote:
> Hello, list!
> 
> I am in the midst of configuring a new Dovecot IMAP server, and I'm
> preparing to setup shard mailboxes as part of the ocnfiguration. In
> order to get these setup the way I want, I've figured out that I'm
> going to have to setup an acl_shared_dict. This is where things start
> to get confusing for me, as I have had difficulty finding thorough
> explanations of dictionary configuration.
> 
> My primary concern is that all my user details are stored in a sqlite
> database in which the '%n' and '%d' components of
username/email
> addresses are stored in separate columns. The SQL dictionary example
> in the Shared Mailboxes document
> [http://wiki2.dovecot.org/SharedMailboxes/Shared] assumes that the
> username is stored as a singular '%n@%d' key. In my authdb lookups,
I
> use sqlite syntax to concatenate the '%n' and '%d' columns
around a
> '@' character to find the user. Is it possible to implement an
> acl_shared_dict in some similar fashion?
> 
> My second question, which is completely unrelated and more out of
> morbid curiosity than anything (although it could affect my
> configuration decisions) is that I noticed every dictionary which
> shows up in the documentation has a "pattern" field. In the case
of
> the acl_shared_dict example, the pattern is
> 'shared/shared-boxes/user/$to/$from'. I couldn't figure out by
> studying the example where this value was derived from, or indeed
> where it is derived from in any example dictionaries which are
> documented. Can anyone explain the meaning of the "pattern" field
and
> what exactly its value means?
> 
> Thanks in advance for all your helpful answers! :)