RE: [Bug 7986] New: Eventing: supported notification policy

Hi Li,
  you are correct that someone could annotated the NotificationWSDL with 
the policy, however NotificationWSDL is optional and in environments where 
the list of events/notifications is very dynamic then they may not choose 
to expose any NotificationWSDL for each Format it supports.  For example, 
they may choose to just expose Event Descriptions. So, in the absence of 
NotificationWSDL we need a way for someone to still know how to subscribe. 


thanks
-Doug
______________________________________________________
STSM |  Standards Architect  |  IBM Software Group
(919) 254-6905  |  IBM 444-6905  |  dug@us.ibm.com
The more I'm around some people, the more I like my dog.



"Li, Li (Li)" <lli5@avaya.com> 
Sent by: public-ws-resource-access-request@w3.org
11/05/2009 11:32 AM

To
<public-ws-resource-access@w3.org>
cc
"Chou, Wu (Wu)" <wuchou@avaya.com>
Subject
RE: [Bug 7986] New: Eventing: supported notification policy






Hi Doug,

I'd like to get some clarification on this issue [1]. You stated two
points:

1) Right now there doesn't appear to be a way for an event source
to advertise how it can send Notifications.  By this I mean,
how does a Subscribe know what policy assertions it can put into
the NotifyTo EPR?  The QoS for the Event Source ops, meaning the
Subscribe operations, could be very different from the QoS that's
supported when it comes to sending Notifications.

2) Add to ws-eventing (new section 9.3) the notion of using MEX to
retrieve the
Notification Policy.  So sending a mex.GetMetadata like this:

   <mex:GetMetadata>
      <mex:Dialect URI="http://www.w3.org/ns/ws-policy"
         Identifier= "http://www.w3.org/2009/02/ws-evt/Notifications" />
   </mex:GetMetadata>

will return the Policy assertion that the Subscriber can use during
a Subscribe().


For point 1), if I understood correctly, an event source can attach
policy assertions to the notification WSDL specified in A.2 of WS-E. 

For point 2), if I understood correctly, a subscriber can use MEX to
retrieve this notification WSDL and obtain the policy in it as specified
in A.2.1 of WS-E. 

Could you clarify what is the relation of this new proposed mechanism
and those available in A.2? 

Thanks.

Li

[1] http://www.w3.org/Bugs/Public/show_bug.cgi?id=7986