Re: WSDL and pub/sub

Taking this one step further, and emphasizing that I am simply musing
about this topic and not in any way representing the official position
of the ebXML Registry TC:

The only catch to this approach would be that - in the current ebXML
Registry specs (and I don't represent this as a shortcoming in any way)
- the subscription is represented using the native registry query
mechanisms, while WS-Eventing wants an XPath expression as a filter.
Here's an example from the ebXML Registry Services spec v2.5, in which a
SQL Query expression is defined for a subscription:

SELECT * FROM Service s, AuditableEvent e, AffectectedObject ao, 
              Classification c1, Classification c2 
              ClassificationNode cn1, ClassificationNode cn2 WHERE 
         e.eventType = 'Created' AND ao.id = s.id AND ao.parent=e.id AND 
         c1.classifiedObject = s.id AND c1.classificationNode =
cn1.id           AND 
         cn1.path LIKE '%Plumbing' AND 
         c2.classifiedObject = s.id AND c2.classificationNode =
cn2.id           AND 
         cn2.path LIKE '%A Little Town%'

Kind Regards,
Joe Chiusano
Booz | Allen | Hamilton
Strategy and Technology Consultants to the World

Ugo Corda wrote:
> 
> Yes, something like that. WS-Notification has more sophisticated
> functionality than WS-Eventing, like brokered notification, topic spaces
> and subscription managers, but probably ebXML Registry does not need
> those and WS-Eventing would be sufficient.
> 
> As Monica mentioned, the fact that these specs are not currently open
> presents problems, but that might change soon if the authors make good
> their promise to submit to standard organizations.
> 
> Ugo
> 
> > -----Original Message-----
> > From: Chiusano Joseph [mailto:chiusano_joseph@bah.com]
> > Sent: Monday, February 16, 2004 12:17 PM
> > To: Ugo Corda; Monica J. Martin; Farrukh Najmi; Burdett
> > David; Andrew Berry; Steve Ross-Talbot; WS Choreography
> > Subject: Re: WSDL and pub/sub
> >
> >
> > I thought about this more (up for a good challenge today):
> >
> > If we were to do this for ebXML Registry, we would first need
> > to create a third interface to the registry (in addition to
> > the current QueryManager and LifeCycleManager interfaces) for
> > Event Notification. All notification messages would be sent
> > on this interface. With this approach, and if we were
> > (hypothetically) to implement WS-Eventing, a subscribing Web
> > Service would use a wse:Filter expression to filter for
> > events that pertain to the RegistryObject(s) of its interest.
> >
> > Is this along the lines of what you're thinking?
> >
> > Kind Regards,
> > Joe Chiusano
> > Booz | Allen | Hamilton
> >
> > Chiusano Joseph wrote:
> > >
> > > Same with ebXML Registry. I think I should defer to Farrukh at this
> > > point for a more detailed explanation. :)
> > >
> > > Ugo Corda wrote:
> > > >
> > > > I am not sure what you mean by "a Web Service that is external to
> > > > the registry contents". In UDDI, all interactions with registry
> > > > contents occur via Web service interfaces, and I thought the same
> > > > was true for the ebXML Registry.
> > > >
> > > > Ugo
> > > >
> > > > > -----Original Message-----
> > > > > From: Chiusano Joseph [mailto:chiusano_joseph@bah.com]
> > > > > Sent: Monday, February 16, 2004 11:37 AM
> > > > > To: Ugo Corda
> > > > > Cc: Monica J. Martin; Farrukh Najmi; Burdett David;
> > Andrew Berry;
> > > > > Steve Ross-Talbot; WS Choreography
> > > > > Subject: Re: WSDL and pub/sub
> > > > >
> > > > >
> > > > > I believe that that is certainly one possible approach, and if
> > > > > there were open Web Services eventing standards (meaning open
> > > > > standards body) available at the time that the Event
> > Notification
> > > > > feature were architected it may/may not have been done
> > this way.
> > > > > However, would it be possible (or even
> > > > > efficient) to have a subscriber be notified by a Web
> > Service that
> > > > > is external to the registry contents about and event
> > that happened
> > > > > to a RegistryObject within the registry? I could be off
> > base, but
> > > > > it seems to me that a more efficient approach is to have the
> > > > > subscription "close" to the contents themselves.
> > > > >
> > > > > Kind Regards,
> > > > > Joe Chiusano
> > > > >
> > > > > Ugo Corda wrote:
> > > > > >
> > > > > > I would have thought that an ebXML Registry client would
> > > > > subscribe to
> > > > > > the Registry itself (seen as a Web service) in order to get
> > > > > > notifications on events related to the contents you
> > > > > describe. Is that
> > > > > > not so?
> > > > > >
> > > > > > Thank you,
> > > > > > Ugo
> > > > > >
> > > > > > > -----Original Message-----
> > > > > > > From: Chiusano Joseph [mailto:chiusano_joseph@bah.com]
> > > > > > > Sent: Monday, February 16, 2004 11:02 AM
> > > > > > > To: Monica J. Martin
> > > > > > > Cc: Ugo Corda; Farrukh Najmi; Burdett David; Andrew Berry;
> > > > > > > Steve Ross-Talbot; WS Choreography
> > > > > > > Subject: Re: WSDL and pub/sub
> > > > > > >
> > > > > > >
> > > > > > > It would also be highly unlikely that the ebXML
> > Registry adopt
> > > > > > > WS-Eventing or WS-Notification from the standpoint of their
> > > > > > > main mission. The event notification feature of the registry
> > > > > is based on
> > > > > > > registry contents (subscriptions to RegistryObjects, etc.)
> > > > > > > rather than subscriptions to Web Services themselves.
> > > > > > >
> > > > > > > Kind Regards,
> > > > > > > Joe Chiusano
> > > > > > > Member, ebXML Registry TC
> > > > > > >
> > > > > > > "Monica J. Martin" wrote:
> > > > > > > >
> > > > > > > > >Corda: Farrukh,
> > > > > > > > >
> > > > > > > > >Do you guys have any plan of adopting one of the
> > > > > emerging pub/sub
> > > > > > > > >specs, i.e. WS-Eventing or WS-Notification?
> > > > > > > > >
> > > > > > > > >Thank you,
> > > > > > > > >Ugo
> > > > > > > > >
> > > > > > > > >
> > > > > > > > mm1: I believe someone on this list has already
> > questioned
> > > > > > > > the implications of any open standards' body adopting
> > > > > > > > proprietary specifications.
> > > > > > >
> > > > >
> >

Received on Monday, 16 February 2004 15:43:31 UTC