RE: [wsn] New Issue: SubscriptionManager Interface in BrokeredNotification

[Lily Liu <lily.liu@webmethods.com>]

Yes, the main concern of the issue was the inconsistency indicated in the spec. Steve's suggestion will eliminate the issue.

 

The issue also touches another interesting question: what is our definition of a broker? To me, a broker manages subscriptions itself, or knows how to talk to a subscription management module. Consumers and Producers only talk with the broker. From this point of view, I prefer adding the SubscriptionManager inheritance to NotificationBroker.

 

Thanks.

 

Lily

-----Original Message-----
From: Steve Graham [mailto:sggraham@us.ibm.com]
Sent: Wednesday, March 02, 2005 4:28 AM
To: Patil, Sanjay
Cc: Lily Liu; wsn@lists.oasis-open.org
Subject: RE: [wsn] New Issue: SubscriptionManager Interface in BrokeredNotification

"Patil, Sanjay" <sanjay.patil@sap.com> wrote on 03/01/2005 10:15:14 PM:

> I believe the intent here may have been to point out that the broker role is a
> composition of producer and consumer roles. However, I am with you in that we
> should clarify whether and how this role composition translates to assuming support
> for WSDL Interfaces.
With respect to the composition of the producer and consumer roles, this is
captured in the NotificationBroker portType.  What is missing from that?

>  
> In addition to clarification text in the spec, the WSDL/Schema for the  BrokeredN
> should perhaps also include a copy of the SubscriptionManager PortType from the
> BaseN. Or should there be a wsdl:include of BaseN WSDL in the BrokeredN WSDL?
I am not sure we should increase the size of the WSDL/Schema for BrokeredN.  Why
is it not sufficient for the Broker to delegate to another SM service?
Another alternative to this issue is to modify the requirement text:

(starting line 100 of the 21 July 2004 draft of BrokeredN):
Must allow for a notification broker as an intermediary. A
NotificationBroker is an intermediary Web service that decouples
NotificationConsumers from Publishers. A notification broker can relieve a
Publisher from having to implement message exchanges associated with
NotificationProducer; the NotificationBroker takes on the duties of a
SubscriptionManager (managing subscriptions) and NotificationProducer
(distributing NotificationMessages) on behalf of the Publisher.

Perhaps it is the "takes on the duties of a SubscriptionManager" that is the
text in concern?  We could rephrase that to include the notion that
a NB could implement SM or it could delegate the behavior.  The net result is
that the responsibility of managing subscriptions is removed from the publisher
by the Broker.

>  
> Thanks,
> Sanjay
> -----Original Message-----
> From: Lily Liu [mailto:lily.liu@webmethods.com]
> Sent: Tuesday, Mar 01, 2005 9:43 AM
> To: wsn@lists.oasis-open.org
> Subject: [wsn] New Issue: SubscriptionManager Interface in BrokeredNotification

> In the WS-BrokeredNotification specification, it states that a broker should take
> on subscription manager duties in the Requirement section. However, it only lists
> out two interfaces that a NotificationBroker inherits: NotificationProducer and
> NotificationConsumer. I think we should add SubscriptionManager to that list.
>  
> Lily