[JDEV] MUC problems
David Sutton
jabber at dsutton.legend.uk.com
Thu Feb 13 23:39:44 CST 2003
Hello all,
I've spent some time thinking about this over the evening.
On Thu, Feb 13, 2003 at 03:01:33PM -0600, Peter Saint-Andre wrote:
> First of all, the question here is related more to browse implementation
> than MUC implementation. Unfortunately, the browse specification is not
> consistent with usage such as this:
>
> <iq
> type='result'
> id='1011'
> to='xxx at localhost/coccinella'
> from='girls at conference.localhost'>
> <conference xmlns='jabber:iq:browse' name='girls' type='public'>
> <ns>http://jabber.org/protocol/muc</ns>
> <user name='mats'
> jid='girls at conference.localhost/13c6a01dc31309e331c2b018640b9c03b8534327'/>
> </conference>
> </iq>
>
> The browse JEP (which is incomplete) does not seem to allow <conference/>
> as a root element for the jabber:iq:browse namespace (there is no DTD or
> schema so we can't be sure, but it appears that <item/> is the root
> element and as we know only one root element should be allowed). In
> addition, it does not define <user/> as a child element of the root
> element. So I would say that the above stanza is questionable from the
> perspective of browse.
>
I will review the browse and see if it is possible to return with a
result which follows the meaning of the JEP. The existing method was
used to provide compatability to the existing conference system running
on jabber.org.
>
> Second, given the ambiguities involved in browse, it may behoove the
> author of JEP-0045 to remove all references to browse and require support
> for disco only. However, I am loath to do so until disco goes to Draft, so
> it is possible I will hold off on submitting JEP-0045 to the Council until
> disco is advanced to Draft.
>
Until the debate on browse reaches some stability, i've removed the
browse code from the MU-Conference cvs. I've already heard from people
who feel that it is a bad idea to remove browse, as it already has place
in many of the existing clients. Another expressed concern that disco
made it more complicated to retrieve the data necessary. What I may do
is make browse an optional extra which can be enabled or disabled at the
service admins choice. If I do this, then the SHA hash idea (for
representing a users true jid, not roster entry) may also be an option.
I really perceive this being of use in certain situations, even if
others may not yet.
>
> Third, I would agree with Constantin that the hashed resource in the 'jid'
> attribute in the stanza shown above is inconsistent with the spirit of
> MUC. Note example 10 in version 1.3 of JEP-0045:
>
I think that the issue is being slightly missed here. the response to
disco#items already does report in the syntax given below. The current
debate about SHA hash jids is in relation to browsing for a users real
jid, not for a room roster. I had already rewritten browse (and disco
iirc) so that for the room listings, it reported them in the format
roomname at service/nick. Only browsing a user for their true jid in
semi-anonymous rooms returned a hash, to provide a form of
accountability. Does this make the point I am trying to make clearer?
On the issue of disco, I also recall a debate going on because the exact
details of what items were to be returned was not defined. There are
several possibilities, such as room roster, member list, moderator list,
admin list and so on. Was a decision made on which data should be
returned, and if there was a way to return any of the other information
via the disco interface?
>
> Example 10. Room Returns Disco Item Results (Items are Public)
>
> <iq
> type='result'
> from='darkcave at macbeth.shakespeare.lit'
> to='hag66 at shakespeare.lit/pda'
> id='disco4'>
> <query xmlns='http://jabber.org/protocol/disco#items'>
> <item jid='darkcave at macbeth.shakespeare.lit/firstwitch'/>
> <item jid='darkcave at macbeth.shakespeare.lit/secondwitch'/>
> </query>
> </iq>
>
> In this instance, the user information is public and the implementation
> returns each user's room JID (not a hash).
>
> If user information is *not* public, then the implementation SHOULD return
> empty results, not hashed information, as in Example 11:
>
> Example 11. Room Returns Empty Disco Item Results (Items are Private)
>
> <iq
> type='result'
> from='darkcave at macbeth.shakespeare.lit'
> to='hag66 at shakespeare.lit/pda'
> id='disco4'>
> <query xmlns='http://jabber.org/protocol/disco#items'/>
> </iq>
>
> Or at least so it seems to me. Thoughts?
>
Disco returning an empty list makes sense, although it was this that
reminded me of the point I made above regarding different lists.
Hope this makes my point a little clearer.
>
> Peter
>
> --
> Peter Saint-Andre
> Jabber Software Foundation
> http://www.jabber.org/people/stpeter.php
>
> On Tue, 11 Feb 2003, Constantin Nickonov wrote:
>
> > I understand what you're trying to do. The problem is that your methods
> > conflict with the intent of JEP-0045, which will eventually result in
> > fragmentation of the standard, i.e., when two or more implementations of MUC
> > accomplish the same thing in incompatible ways. Perhaps the JEP should be
> > more specific when it comes to laying out the 'jabber:iq:browse'
> > capabilities (which are being phased out in favor of disco), but it seems to
> > me the re-introduction of SHA-hashing for this purpose is not a good thing.
> >
> > Sure, you can talk about race conditions, like when I browse to get a list
> > of users and one of them chooses that moment to change his nick, making my
> > subsequent user-level browse requests invalid. But why not just return the
> > real JID (if it's allowed by the room) in the room-level browse result?
> > Something like this:
> >
> > SENT: <iq type='get' to='room at muc.server'>
> > <query xmlns='jabber:iq:browse'/>
> > </iq>
> > READ: <iq type='result' to='user at server/resource' from='room at muc.server'>
> > <conference xmlns='jabber:iq:browse' name='room' type='public'>
> > <ns>http://jabber.org/protocol/muc</ns>
> > <user name='nick1' jid='user2 at server/resource'/>
> > </conference>
> > </iq>
> >
> > In the case of an anonymous room, the 'jid' attribute could be omitted (or
> > contain the in-room JID for that user, i.e., 'room at muc.server/nick2').
> >
> > > -----Original Message-----
> > > From: David Sutton [mailto:jabber at dsutton.legend.uk.com]
> > > Sent: Tuesday, February 11, 2003 8:59 AM
> > > To: jdev at jabber.org
> > > Subject: Re: [JDEV] MUC problems
> > >
> > >
> > > Hello there,
> > >
> > > We are both correct in this situation. The JEP does define
> > > how the jid
> > > is to be handled for a presence packet, and MU-Conference follows
> > > that. You will never see the SHA1 string in a presence packet.
> > >
> > > On the other hand, the system of using an iq request, xmlns
> > > jabber:iq:browse, to discover the room roster is not covered by the
> > > JEP. In order to maintain sanity, I have opted to continue using the
> > > existing methods. If you require to see the real jid, and you are
> > > allowed, then browsing the SHA1 resource will reveal the true jid. I
> > > have to use the sha1, since it allows you to track the user more
> > > consistantly - as I tried to explain before, I could use
> > > 'girls at conference.localhost/NICK' for the nickname reported
> > > by browse,
> > > the problem is that if users swap nicknames, I have no way
> > > of knowing
> > > that is what happened. The SHA1 string is unique to that user.
> > >
> > > Regards,
> > >
> > > David
> > >
> > > On Tue, Feb 11, 2003 at 08:12:16AM -0700, Constantin Nickonov wrote:
> > > > see below
> > > >
> > > > > -----Original Message-----
> > > > > From: David Sutton [mailto:jabber at dsutton.legend.uk.com]
> > > > > Sent: Monday, February 10, 2003 8:51 PM
> > > > > To: jdev at jabber.org
> > > > > Subject: Re: [JDEV] MUC problems
> > > >
> > > > <snip>
> > > >
> > > > > The hex string is actually a SHA1 hash of the users real
> > > jid. Its used
> > > > > to reference a user, but not reveal the true jid. If the room
> > > > > is set up to allow people to see the real jid, then just browse
> > > > >
> > > girls at conference.localhost/13c6a01dc31309e331c2b018640b9c03b85
> > > 34327 and
> > > > > it will show you the true jid. This also helps to keep
> > > compatability to
> > > > > existing clients that are used to this form with the
> > > > > groupchat/conferencing module. The real jid is used as
> > > the reference, as
> > > > > a person can keep changing their nick throughout a
> > > session, but they
> > > > > can't change their real jid
> > > >
> > > > The problem with this is that the MUC standard (JEP-0045)
> > > specifies how
> > > > nicknames are passed along with presence information, and
> > > how they are
> > > > changed -- and SHA-hashing isn't the way.
> > > >
> > > > Entering a room (JEP-0045, section 6.2):
> > > >
> > > > SENT: <presence to='foo at muc.server/nick1'>
> > > > <x xmlns='http://jabber.org/protocol/muc'/>
> > > > </presence>
> > > > READ: <presence from='foo at muc.server/nick1'
> > > to='user at server/resource'>
> > > > <x xmlns='http://jabber.org/protocol/muc#user'>
> > > > <item affiliation='owner' jid='user at server/resource'
> > > > role='moderator'/>
> > > > </x>
> > > > </presence>
> > > >
> > > > Changing the nick (JEP-0045, section 6.4):
> > > >
> > > > SENT: <presence to='foo at muc.server/nick2'/>
> > > > READ: <presence type='unavailable' from='foo at muc.server/nick1'
> > > > to='user at server/resource'>
> > > > <x xmlns='http://jabber.org/protocol/muc#user'>
> > > > <item nick='nick2' affiliation='owner'
> > > > jid='user at server/resource' role='moderator'/>
> > > > <status code='303'/>
> > > > </x>
> > > > </presence>
> > > > <presence from='foo at muc.server/nick2'
> > > to='user at server/resource'>
> > > > <x xmlns='http://jabber.org/protocol/muc#user'>
> > > > <item affiliation='owner' jid='user at server/resource'
> > > > role='moderator'/>
> > > > </x>
> > > > </presence>
> > > >
> > > > The MUC protocol wasn't designed to be fully
> > > backward-compatible with the
> > > > JCF draft.
> > > >
> > > > Constantin
> > > > _______________________________________________
> > > > jdev mailing list
> > > > jdev at jabber.org
> > > > http://mailman.jabber.org/listinfo/jdev
> > >
> > > --
> > > David Sutton
> > > Email: dsutton at legend.co.uk
> > > Jabber: peregrine at legend.net.uk
> > >
> > _______________________________________________
> > jdev mailing list
> > jdev at jabber.org
> > http://mailman.jabber.org/listinfo/jdev
> >
>
>
>
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--
David Sutton
Email: dsutton at legend.co.uk
Jabber: peregrine at legend.net.uk
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