Notification distributor for XMPP

[Peter Suter]

The new INotificationDistributor interface allows distributing notifications over different transport channels. So far we only have an email distributor. We could also provide XMPP support in tracopt.

[Peter Suter]

Announcer's ​XmppDistributor seems to ​depend on ​xmpppy. (Is GPL license a problem for optional dependencies?)

[Peter Suter]

log:psuter.hg@T11884-xmpp is based on that.

The XMPP Address preference child panel complements Email Address on the General (alias None) panel.

Still not sure if IEmailAddressResolver should be more general, so SessionEmailResolver​ is basically inlined into XmppDistributor.get_address_for_session​ instead.

[Jun Omae]

I think we must separate tracopt/notification/xmpp.py to an external plugin with GPL-compatible license, like TracMercurial. Trac doesn't bundle Mercurial plugin because mercurial's license is GPL.

[Peter Suter]

Alternatively we could use a different library. ​SleekXMPP seems to be popular and is MIT licensed. Would bundling be possible in that case?

(Another one is ​Wokkel, also MIT. Seems inactive at the moment.)

We could also add a IXmppSender (similar to IEmailSender) that just makes that library pluggable. I'm not sure it's worth it. What do you think?

Edit: jQuery for example is also bundled with Trac and MIT licensed, so that seems possible.

[Jun Omae]

Replying to psuter:

Alternatively we could use a different library. ​SleekXMPP seems to be popular and is MIT licensed. Would bundling be possible in that case?

Yeah. Using ​SleekXMPP would lead no license problems.

We could also add a IXmppSender (similar to IEmailSender) that just makes that library pluggable. I'm not sure it's worth it. What do you think?

IMO, the interface isn't needed. I'm also not sure about the worth.

[Peter Suter]

log:psuter.hg@T11884-xmpp updated to switch to SleekXMPP.

[Peter Suter]

The trac-admin commands session list, session add and session set implemented by SessionAdmin​ also handle session email addresses. I'm not sure if / how XMPP addresses could or should be handled. I guess a separate set of commands (e.g. session xmpp set etc.) could be implemented in tracopt.

[Ryan J Ollos]

Replying to jomae:

I think we must separate tracopt/notification/xmpp.py to an external plugin with GPL-compatible license, like TracMercurial. Trac doesn't bundle Mercurial plugin because mercurial's license is GPL.

Right, but the proposed changes don't include the source for XMPP, the changes just use XMPP as a packaged dependency. My understanding, which is not thorough by any means, is that it's okay to use dependencies that have a GPL license, as long as we don't directly distribute the source code with Trac. Consider that ​MySQLdb appears to be GPL licensed and is used by Trac in a similar way to the proposed changes that would use the XMPP library.

[Jun Omae]

Replying to rjollos:

Consider that ​MySQLdb appears to be GPL licensed and is used by Trac in a similar way to the proposed changes that would use the XMPP library.

MySQLdb is dual-licensed under GPLv2 and Python License. See ​https://github.com/farcepest/MySQLdb1/blob/MySQLdb-1.2/INSTALL#L249.

[Ryan J Ollos]

Okay, possibly MySQLdb isn't a good example - I don't know what the terms of Python's 1.5.2 license are.

I still question whether or not we can use a packaged dependency that has a GPL license. ​StackExchange post suggests we cannot use GPL licensed packages.

[Ryan J Ollos]

Narrowing focus for milestone:1.2. Please move ticket to milestone:1.2 if you intend to fix it.

[Peter Suter]

Replying to Peter Suter:

The trac-admin commands session list, session add and session set implemented by SessionAdmin​ also handle session email addresses. I'm not sure if / how XMPP addresses could or should be handled. I guess a separate set of commands (e.g. session xmpp set etc.) could be implemented in tracopt.

comment:10:ticket:11840 mentions extending these commands with a new interface.

[Ryan J Ollos]

Milestone renamed