W3C home > Mailing lists > Public > www-ws-arch@w3.org > February 2003

Re: Resource definition

From: James M Snell <jasnell@us.ibm.com>
Date: Tue, 18 Feb 2003 21:53:38 -0800
To: Christopher B Ferris <chrisfer@us.ibm.com>
Cc: www-ws-arch@w3.org, www-ws-arch-request@w3.org
Message-ID: <OFD17C037F.83C0856D-ON88256CD2.001FB58F-88256CD2.00206066@us.ibm.com>

You have a resource.
There are a number of state transitions that a resource consumer can 
affect upon that resource.
There are a number of state properties that a resource consumer can query 
about that resource.
How you affect those state transitions and how you query those properties 
depends on your choice of protocol.
REST, Web services, etc are all examples of protocols.

Mark is correct when looking at everything from the REST point of view. 
There are other valid points of view, meaning that there are other 
protocols that can be used to affect the same state transition.

Pretty much end of story. 

- James Snell
     IBM Emerging Technologies
     jasnell@us.ibm.com
     (559) 587-1233 (office)
     (700) 544-9035 (t/l)
     Programming Web Services With SOAP
         O'Reilly & Associates, ISBN 0596000952

     Have I not commanded you? Be strong and courageous. 
     Do not be terrified, do not be discouraged, for the Lord your 
     God will be with you whereever you go.    - Joshua 1:9



Christopher B Ferris/Waltham/IBM@IBMUS
Sent by: www-ws-arch-request@w3.org
02/18/2003 08:15 PM

To
www-ws-arch@w3.org
cc

bcc

Subject
Re: Resource definition





Mark Baker wrote on 02/18/2003 08:33:22 PM:

> 
> On Tue, Feb 18, 2003 at 04:38:54PM -0800, Burdett, David wrote:
> > In an earlier email, Francis McCabe said ...
> > 
> > >>>... to use one of Mark's earlier examples, turning on a light 
switch. The
> > state of the light is a representable resource; no question. The 
action of
> > flipping the switch is not so representable. The arm which is used to 
flip
> > the switch is, however, a resource; although any representation of it 
in
> > terms of bits is merely a symbol and not the real thing.<<<
> > 
> > So is the act of moving the arm to turn on/off the switch a resource?
> 
> Well, I suppose you could make it one, but I'm not sure what that
> would accomplish.
> 
> One doesn't need to talk about a switch, or the movement of a switch, or
> even a toggleSwitch() method, in order to effect a state change with the
> bulb, because the interaction style is one of *state transfer*; if I
> want to turn the bulb on, I just do a HTTP PUT containing a
> representation of the "on state" to the URI identifying the lightbulb. 

Yes, assuming you knew what that representation was, and assuming that the 

PUT method is supported by the resource... 

> 
> MB
> -- 
> Mark Baker.   Ottawa, Ontario, CANADA.        http://www.markbaker.ca
> Web architecture consulting, technical reports, evaluation & analysis
>  

Cheers,

Christopher Ferris
Architect, Emerging e-business Industry Architecture
email: chrisfer@us.ibm.com
phone: +1 508 234 3624 
Received on Wednesday, 19 February 2003 00:53:43 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 3 July 2007 12:25:15 GMT