[Gaim-devel] Bonjour and XMPP

[Evan S. <ev...@ad...>]

I'd like to start a cross-list Adium/Gaim dialogue about the future  
of Bonjour, especially as it relates to XMPP.

Apparently, the Bonjour protocol as implemented by iChat is a small  
subset of XMPP but there's no reason not to fully support everything  
XMPP has to offer.  That includes, of course, eventual Talk support  
via libjingle, just-as-a-for-instance.  The only part of XMPP which  
is excluded when using Bonjour is the roster, it appears.

We discussed this a bit on adium-dev already.  Adium currently  
utilizes libezv, a BSD licensed implementation of Bonjour which is  
approximately where the libgaim bonjour prpl is at present (presence,  
messaging, typing status) with what I believe are a few extras (buddy  
icon support) but some similar limitations (no file transfer, for  
example).  One thing libezv *does* get us in Adium is the use of OS  
X's systemwide mDNS stack via native calls.

Really, as I understand it, Bonjour is XMPP but with (1) different  
network code, which routes through an mDNS stack instead of  
traditional network calls and (2) different presence handling,  
especially since there is no Bonjour Roster.

What if the Jabber prpl were split, similarly to how Oscar was split  
into AIM and ICQ, but with a significantly greater degree of split  
complexity?

Jabber and Bonjour wouldn't be treated as the same protocol in terms  
of what a user (or a UI) saw, but at the heart they could share the  
vast majority of their code.  Bonjour would do network activity via  
GaimBonjourMDNSCallback functions, or the like, such that the UI  
would be able to use the best available library.  In the case of  
Gaim, that would be Howl initially but hopefully Avahi in the  
future.  In the case of Adium, this would be the appropriate  
DNSServiceDiscovery and CoreFoundation framework calls.

We have a couple strong Google Summer of Code proposals related to  
Bonjour that we're considering for Adium, and I see a number of  
proposals related to it in the Gaim GSoC applications list, as well.   
A project in this direction could have big payoff, especially looking  
forward: we would bring a mature, capable, growing XMPP  
implementation to Bonjour, raising the bar as to what a Bonjour  
client can and should do.  The time to think about this and discuss  
it is now, while we have interested students looking to get involved  
in an important project and before we allow them to work in a  
direction which might soon be reversed.

Thoughts? Please reply-to-all; my apologies for the extra traffic to  
those of you who are subscribers of both lists.

-Evan