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RE: Can someone recap the differences between @serviceGroup vs. definitions-targetNamespace ?

From: Jim Webber <jim.webber@arjuna.com>
Date: Wed, 16 Jul 2003 12:38:25 +0100
To: "'Umit Yalcinalp'" <umit.yalcinalp@oracle.com>
Cc: <www-ws-desc@w3.org>
Message-ID: <006d01c34b8e$c4e902b0$880a090a@kyle>

Umit:

> In this case, the resource shared is probably a printerdatabase. The 
> representation of the id of an individual printer is left to the web 
> service, but you still have a way to infer that these two 
> services share 
> the resource, namely the printer database, not the printer.  

Why? The printer database is as private to the service(s) as the printers
themselves. I think it is wrong to provide shared identity based on exposing
a private physical resource - which are logically and physically of no
concern to the consumer of a service.

[snip]

> The relationship is defined based on the word manipulate, no more, no 
> less :-)

And I assert that you cannot advertise "Hey, these two services both prod
this printer(or database) over here" in a service interface. What value is
that when I shouldn't be able to see that printer (or database) anyway other
than to share a unique string?


> For those of us who consider state to be related to an 
> entity's id, the 
> targetResource provides the necessary relationship, namely 
> the "id" of 
> the underlying entity that is shared by various services.

State is context driven. An ATM does not contain my state because it is a
service. When I interact with an ATM I have to provide context in the form
of my ATM card, and using that context the back-end of the ATM can
manipulate its resources appropriately. I would be inappropriate for an ATM
to advertise that its targetResource was my bank account, just so that I can
see that I can use another ATM to manipulate that bank account (perhaps in
colour or in a different language).

> As long as the serviceGroup construct  makes multiple 
> groupings possible 
> AND ALSO allows identifies the targetResource grouping in a 
> special way, 
> wouldn't that outcome be acceptable for everybody?

No - then we give the developer so much rope they will have to hang
themselves hundreds of times just to use it all. 

Can we just not go back to allowing mulitiple interfaces per service and
declare victory?

Jim
Received on Wednesday, 16 July 2003 07:38:35 GMT

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