[Warning: experimental]

"Cat project" not "pet project"--you are going to put a lot into it but don't expect anything back -- Kent Beck on Twitter

Zimbratosthenes aims at bridging the gap between Zimbra's mail filters and the Sieve language allowing to describe mail filters as simple text files.

zbt

If no argument is given, zbt will download current mail filters from the Zimbra server and convert them to sieve rules, displayed on standard output. :

zbt file.sieve

If an argument is given, zbt will parse the file as a list of sieve rules and then upload them to the Zimbra server. '-' can be used to use standard input.

Zimbra admins can actually more or less import Sieve filters for a given user as explained in https://wiki.zimbra.com/index.php?title=Email_Rules_Migration.

However, it is a shame that an end-user has no other way to manage her filters than to access the Web server. I personally read my mail through IMAP, access my calendar through CalDAV, and thus filters are the only thing that kept me opening the web server from time to time.

However, that also meant that I wasn't able to automatically update filters in any case (e.g., frequent sender in my Junk box), or to trigger a modification to a filter from my mail client…

Nevertheless, I discovered that Zimbra's mail filters can be accessed and modified through Zimbra SOAP API hence was born Zimbratosthenes.

Unfortunately Zimbra does not support precisely Sieve, nor any of its extensions, the mapping is thus quite fragile, but if you build a few rules in the web interface, they should be easy to edit later on.

All filters available except reply/notify/addressbook are translated to Sieve with some extensions. For instance the variables extension is used to store the name and activity status of a filter rule.

Let us look at an example:

require ["date", "relational", "fileinto", "imap4flags", "body", "variables"];

set "name" "dummy";
set "active" "0";
if allof (
   header :contains ["subject"] ["fizz"],
   not header :contains ["from"] ["buzz"],
   header :is ["to", "cc"] ["foo"],
   not header :matches ["X-bar"] ["*none?"],
   size :over 10485760,
   not date :value "ge" "date" "2014-01-01",
   body :contains "baz",
   not exists ["X-dummy"]
) {
   keep;
   tag "Old";
   addflag "\\Seen";
   fileinto ".pipe";
   redirect "example@example.com";
   discard;
   stop;
}

Zimbra defіnes always an allof or anyof condition, Zimbratosthenes therefore expects such structure, even if there is a single condition.

Similarly, header tests can only target a single header or the couple To, Cc. Size has to be indicated in bytes and gets converted back when sent to Zimbra. The imap4flags extension is supported but only for \\Seen and \\Flagged. The rest mostly works line in Sieve. If there is an error parsing a Sieve file or converting to a Zimbra-compatible filter, a message will be displayed on stderr.

Good luck, this software is still in a very experimental state!

We make a heavy use of python-zimbra and of sievelib.