Luca's meaningless thoughts  

How can you don't love FLOSS?

by Leandro Lucarella on 2010- 06- 11 21:11 (updated on 2010- 06- 11 21:11)
tagged en, floss, jabber, mcabber, migration, psi, python, script - with 0 comment(s)

Let me tell you my story.

I'm moving to a new jabber server, so I had to migrate my contacts. I have several jabber accounts, collected all over the years (I started using jabber a long time ago, around 2001 [1]; in that days ICQ interoperability was an issue =P), with a bunch of contacts each, so manual migration was out of the question.

First I thought "this is gonna get ugly" so I thought about using some XMPP Python library to do the work talking directly to the servers, but then I remember 2 key facts:

  1. I use Psi, which likes XML a lot, and it has a roster cache in a file.
  2. I use mcabber, which has a FIFO for injecting commands via the command line.

Having this two facts in mind, the migration was as easy as a less than 25 SLOC Python script, without any external dependencies (just Python stdlib):

import sys
import xml.etree.ElementTree as et

def ns(s):
        return '{http://psi-im.org/options}' + s

tree = et.parse(sys.argv[1])

accounts = tree.getroot()[0]

for account in accounts.getchildren():
        roster_cache = account.find(ns('roster-cache'))
        if roster_cache is None:
                continue
        for contact in roster_cache:
                name = contact.findtext(ns('name')).strip().encode('utf-8')
                jid = contact.findtext(ns('jid')).strip().encode('utf-8')
                print '/add', jid, name
                print '/roster search', jid
                g = contact.find(ns('groups')).findtext(ns('item'))
                if g is not None:
                        group = g.strip().encode('utf-8')
                        print '/move', group

Voilà!

Now all you have to do is know where your Psi accounts.xml file is (usually ~/.psi/profiles/<your_profile_name>/accounts.xml), and where your mcabber FIFO is (usually ~/.mcabber/mcabber.fifo, but maybe you have to configure mcabber first) and run:

python script.py /path/to/accounts.xml > /path/to/mcabber.fifo

You can omit the > /path/to/mcabber.fifo first if you have to take a peek at what mcabber commands will be executed, and if you are happy with the results run the full command to execute them.

The nice thing is it's very easy to customize if you have some notions of Python, for example, I didn't want to migrate one account; adding this line just below the for did the trick (the account is named Bad Account in the example):

if account.findtext(ns('name')).strip() == 'Bad Account':
        continue

Adding similar simple lines you can filter unwanted users, or groups, or whatever.

And all of this is thanks to:

Thank god for that!

[1]

A few people will be interested in this, but I think the ones that are will appreciate this link :) (in spanish):

http://www.lugmen.org.ar/pipermail/lug-org/2001-December/004482.html