W3C home > Mailing lists > Public > www-ws-desc@w3.org > April 2003

Re: Proposal for Describing Web Services that Refer to Other Web Services: R085

From: Mark Baker <distobj@acm.org>
Date: Mon, 28 Apr 2003 10:48:14 -0400
To: "Amelia A. Lewis" <alewis@tibco.com>
Cc: www-ws-desc@w3.org
Message-ID: <20030428104814.Q23133@www.markbaker.ca>

On Mon, Apr 28, 2003 at 10:09:19AM -0400, Amelia A. Lewis wrote:
> On Sat, 26 Apr 2003 23:19:15 -0400
> Mark Baker <distobj@acm.org> wrote:
> > They can identify any thing, if that's what you mean by "universal".
> 
> TimBL's original proposal was for "universal" identifiers/locators.  The IETF rejected that term, replacing it with "uniform".  They are uniform; they are not universal.

They're wrong, because it's absolutely trivial to test if they're
universal; just try and identify something which cannot have a URI.  It
would only take *one* example to disprove the universal hypothesis, yet
nobody's been able to find one yet.

Do you really doubt that any string can identify anything?  How
would language have evolved if that weren't the case?  "Oh, you can't
use that word for that concept, sorry - our words can only identify
[fill-in-the-blank]".

(follow up on that subject to www-talk@w3.org please).

> > If you mean that URIs aren't universal in the sense that it isn't
> > practical to turn any addressing scheme into them, I can't disprove
> > that, but I can challenge you to provide an example where it would not
> > be practical.
> 
> I already have done so.  Please examine J2EE services, particularly JMS, in their current state, and in at least two implementations.  At the moment, there is no common URI scheme.  I can write a service and make a scheme up, but so can anyone else who wants to.  As URIs, one-offs are useless; the whole point of them is that they are uniform across equivalent services.

JMS doesn't provide an application service, it provides a transport
service.  You said that you used APIs over it; describe one of those for
me, and I'll design you a URI scheme for it.

For example, if you were retrieving stock quotes with JMS, your API
might be "getStockQuote".  If it were, I'd create a URI scheme called
"stockquote" so that quote identifiers could be;

  stockquote://nasdaq/ibm;realtime

I'd then create a SOAP based "stock quote retrieval" application
protocol with "getStockQuote" as its lone application semantic, register
a URI scheme, and then associate this protocol with the URI scheme.

MB
-- 
Mark Baker.   Ottawa, Ontario, CANADA.        http://www.markbaker.ca
Web architecture consulting, technical reports, evaluation & analysis
Received on Monday, 28 April 2003 13:05:25 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:58:23 GMT