From:
Rich Thompson [mailto:richt2@us.ibm.com]
Sent: Monday, July 12, 2004 8:54
PM
To: wsrf@lists.oasis-open.org
Subject: RE: [wsrf] Singleton
Resource Pattern
I did not intend to open such a discussion, but would
note that the current definition of WSDL results in interfaces where each
invocation is completely independent of other invocations. This leaves it to
other protocols to define how any information persisting longer than a single
invocation is referenced. Many, probably even most, protocols have this need
and as a result define their own semantics for returning a reference that must
be supplied on future invocations for the intended statefulness of the
invocations to be maintained.
Rich Thompson
OASIS WSRP TC Chair
"Savas Parastatidis"
<Savas.Parastatidis@newcastle.ac.uk>
07/12/2004 03:18 PM
|
To
|
Rich Thompson/Watson/IBM@IBMUS,
<wsrf@lists.oasis-open.org>
|
cc
|
|
Subject
|
RE: [wsrf] Singleton Resource Pattern
|
|
Hi Rich,
You mention in your message bellow “stateful Web
Service”. What do you mean by that term? Are you suggesting that there
are “stateless Web Services”? I think that the WS-RF TC charter
does not use that term anymore.
Is there a suggestion that Google does not have state for
example? :-)
Regards,
--
Savas Parastatidis
http://savas.parastatidis.name
From: Rich Thompson
[mailto:richt2@us.ibm.com]
Sent: Monday, July 12, 2004 8:03 PM
To: wsrf@lists.oasis-open.org
Subject: RE: [wsrf] Singleton Resource Pattern
What would get/setProperty mean against the standard stateless character of the
base Web Services definition? Before these become useful, you need some manner
of modeling state. It seems to me the primary thrust behind defining WSRF is
having a standard definition of how to model such stateful web services and as
someone who has needed to idiosyncratically model state within the WSRP
protocol, I see a lot of value in that effort.
Rich Thompson
OASIS WSRP TC Chair
"Sedukhin, Igor S"
<Igor.Sedukhin@ca.com>
07/12/2004 02:55 PM
|
To
|
Steve Graham/Raleigh/IBM@IBMUS
|
cc
|
<wsrf@lists.oasis-open.org>
|
Subject
|
RE: [wsrf] Singleton Resource Pattern
|
|
Then what value does the implied pattern add to the use case I have included?
Why does resource pattern have to depend on WS-Addressing, EPRs and
customizations of those?
Why can't GetProperty/SetProperety be defined independently?
-- Igor Sedukhin
.. (igor.sedukhin@ca.com)
-- (631) 342-4325 .. 1 CA
Plaza, Islandia, NY 11788
From: Steve Graham
[mailto:sggraham@us.ibm.com]
Sent: Monday, July 12, 2004 2:44 PM
To: Sedukhin, Igor S
Cc: wsrf@lists.oasis-open.org
Subject: RE: [wsrf] Singleton Resource Pattern
>It seems that whether it is an "implied resource" or an
"implied singleton" has nothing to do with GetResourceProperty
(GetProperty for that sake) operation. In >other words use of WS-Addressing
does not add any semantic value to the fact that one could retrieve a property
by sending a message to a service.
Unfortunately, I disagree. The implied resource pattern clarifies a
certain pattern relating a web service and a stateful resource. It is important
that this pattern is clarified to allow a single web service to act as the Web
services message processor for a plurality of stateful resources. Therefore the
pattern of the message is formed to disambiguate which of the potentially many
stateful resources is associated with the message is very important.
sgg
++++++++
Steve Graham
(919)254-0615 (T/L 444)
STSM, On Demand Architecture
Member, IBM Academy of Technology
<Soli Deo Gloria/>
++++++++
|
"Sedukhin, Igor S"
<Igor.Sedukhin@ca.com>
07/12/2004 11:56 AM
|
To: Steve
Graham/Raleigh/IBM@IBMUS, <wsrf@lists.oasis-open.org>
cc:
Subject: RE: [wsrf] Singleton
Resource Pattern
|
Steve,
Your example was interesting. How about this one:
Web Service implements a UserName property. Client sends a GetResourceProperty SOAP
message with WS-Security headers containing X.509 certificate. Web Service
returns the UserName after matching the certificate.
-- Is this a singleton or an implied resource pattern? One could claim that
there is a user resource, however this interaction does not use WS-Addressing
and moreover it would not be possible to build WS-RF qualified EPRs for such
interaction.
The same use case could be modified to include UserDiskQuota property, and the
same argument would apply.
It seems that whether it is an "implied resource" or an "implied
singleton" has nothing to do with GetResourceProperty (GetProperty for
that sake) operation. In other words use of WS-Addressing does not add any
semantic value to the fact that one could retrieve a property by sending a
message to a service.
-- Igor Sedukhin
.. (igor.sedukhin@ca.com)
-- (631) 342-4325 .. 1 CA
Plaza, Islandia, NY 11788