Sieve failure on deliverdb corruption...

[Rob Mueller]

> We could disable these actions when deliver.db isn't available, but this
> would cause any scripts that use them to fail and you'd see the same
> results.
>
> If we just ignored the fact that deliver.db isn't available, then we'd
> get people complaining about vacation sending out multiple responses, or
> the same message being redirected more than once, etc.

I know that there's no perfect solution, I mean if there was, there wouldn't
be a need for the deliver db in the first place!

Basically it's a question of how to handle failures, and how graceful you
want to be. It's a pity really, because sometimes you really just want to be
able to rely on another piece of software/library, and just assume it always
just works. Given that I haven't seen this problem before (on a fairly large
site), it's not critical, but it was VERY annoying to deal with the support
issues of this happening...

I guess it's a matter of looking at the alternatives, and find the
best/worst:

1. Duplicate DB errors causes mail delivery to fail

a) Email lost/bounced. Really bad.

2. Duplicate DB errors causes sieve to fail

a) Forwarding of messages fails. Possible important messages not forwarded
to work/SMS/pager notification
b) If emails are spam marked and sieve used to filter/reject, this fails,
and ALL messages end up in inbox clogging folder
c) Mailing lists not filed into appropriate folders, clogs inbox again

3. Duplicate DB errors cause multiple vacation responses/redirects

a) Sending multiple emails to users results in multiple vacaction responses
b) Message with same ID redirected to same external address multiple times

Personally I think people will be a lot more annoyed by the 1 & 2 than 3...

Rob