[Telepathy] ANNOUNCE: Dropping legacy telepathy Specs

[Xavier Claessens]

Hi,

The Telepathy spec evolved a lot since its creation, and we always had
kept compatibility in telepathy-glib and Empathy for all old Connection
Managers that does not implement new interfaces. This created lots of
fallback paths, so more complex code to maintain.

In the next few months (GNOME 3.4 cycle), we would like to raise the
expectations we make from Connection Managers. In particular:

1) org.freedesktop.Telepathy.Connection.Interface.SimplePresence is now
mandatory, we won't fallback to
org.freedesktop.Telepathy.Connection.Interface.Presence anymore.

2) org.freedesktop.Telepathy.Connection.Interface.ContactList,
org.freedesktop.Telepathy.Connection.Interface.ContactGroups and
org.freedesktop.Telepathy.Connection.Interface.ContactBlocking are now
mandatory (if your protocol have a roster, not SIP), we won't fallback
to 
org.freedesktop.Telepathy.Channel.Type.ContactList anymore.

3) org.freedesktop.Telepathy.Connection.Interface.Contacts is now
mandatory, we won't fallback to individual getters anymore.

4) org.freedesktop.Telepathy.Channel.Interface.Subject2,
org.freedesktop.Telepathy.Channel.Interface.Room2 and
org.freedesktop.Telepathy.Channel.Interface.RoomConfig1 are now
mandatory (when needed), we won't fallback to Telepathy.Properties
anymore.

5) Latest DBus properties (as per spec 0.24.0) are all mandatory on
org.freedesktop.Telepathy.Channel and
org.freedesktop.Telepathy.Channel.Interface.Group.

6) Immortal handles becomes mandatory as well.

7) We are also planning to make Call1 interfaces mandatory instead of
StreamedMedia and Call-draft1. We need to first port at least
telepathy-gabble, telepathy-rakia and Empathy, so it is still unsure if
it will happen for the GNOME 3.4 time frame, or later.

Those are all deprecated behaviours since a relatively long time, so
making the replacement APIs mandatory is a first step toward upcoming
spec breakage (and thus tp-glib API/ABI) that will remove all deprecated
stuff.

It is important to notice that telepathy-python Connection Managers
(butterfly at least) does *NOT* meet all those requirements. Unless
someone steps up and propose patches, they will be dropped. MSN users
have 2 choices: Using telepathy-haze, or the new XMPP messenger[1].

Regards,
The Telepathy Team.

[1] http://blogs.gnome.org/xclaesse/2011/11/03/msn-in-empathy-with-xmpp/