RE: [wsn] Status notification

["Patil, Sanjay" <sanjay.patil@sap.com>]

There is no open issue that captures this concern, AFAIK.

This topic however triggers me to express some of my thoughts in this regard ...

Notification of life cycle events is a general issue. For example, registries (UDDI, ebXML Registry, ...) today have their own solution for notification of the life cycle events of the registry objects. It may be worthwhile to develop a general purpose model that supports notification of basic life cycle events -- created, changed and destroyed. The model should also be extensible to allow object specific events, for example -- paused and resumed events are specific to Subscription objects that are applicable on top of the common life cycle events (created, changed and destroyed).

We could possibly use the topics mechanism to materialize a solution ..
- When a Subscription X is created, new topics are added to the topic tree - PausedSubscriptionX, ResumedSubscriptionX, ChangedObjectX, TerminatedObjectX, etc.
- Parties interested in life cycle of Subscription X subscribe to the relevant topics. 
- When Subscription X is paused/resumed/terminated, corresponding messages are published on the relevant topics, in addition to undertaking the desired action upon the Subscription.
- Some additional rules may apply such as -- Termination of an object deletes all the life cycle event topics pertaining to that object (after publishing the termination message).

Obviously the above are some very rough ideas. My main question to the TC here is --  In the initial call for participation before forming the TC, we had listed a number of related efforts that may use or require notification pattern in Web services. Some of these efforts clearly require a solution for notification of life cycle events. However, I believe designing a general purpose solution for the notification of life cycle events is not within our current charter. Now either we could remain silent about this problem and allow many different solutions including one for our own purposes, or put a stake in the ground and define a common solution. Just wanted to bring this issue to the TC's attention and get some thoughts ...

Thanks,
Sanjay

> -----Original Message-----
> From: David Hull [mailto:dmh@tibco.com] 
> Sent: Thursday, Aug 05, 2004 9:31 AM
> To: wsn@lists.oasis-open.org
> Subject: [wsn] Status notification
> 
> 
> (Is there already an issue open for this?)
> 
> Whether or not we try to use WSN for its own administration, 
> there needs 
> to be some way for the system to notify the outside world of 
> subscription lifecycle events.  This could be as simple as an 
> optional 
> wsn:StatusReference element in the Subscribe message.  This endpoint 
> would receive notification of pause/resume/modify/destroy events.  It 
> might even be a place to send SubscribeResponse/fault.
> 
>