Proposed Issue Text: Should UseNotify be a policy utterance?

[David Hull <dmh@tibco.com>]

WSN2.XX: Should UseNotify be a  policy utterance?

The SubscribeRequest message currently contains a specialized <UseNotify> element indicating whether the producer should use the Notify message format described in section 3.1.  The Notify message is essentially a convenience and is not fundamental to the basic Subscribe/Notify pattern.  If it were not already in the base specification, it could clearly be added via policy.  As such, it should be treated as a pre-defined policy rather than a built-in feature of notification, just as topic, selector and precondition are now treated as pre-defined filters.

Making this change would bring WSN more closely in line with WSE and would also strengthen the extensibility story concerning policy.

Specifications

• WS-BaseNotification

Proposed Recommendations

Remove the <UseNotify> property from the SubscribeRequest message proper and make it an optional child of the <SubscriptionPolicy> element (and so the first complete entry in the policy document(s)).  The element would retain its current semantics.

Notes

Status:   

Contact:

David Hull, Steve Graham

Cross Reference: