On Thu, Aug 12, 2004 at 02:41:21PM -0400, Michael Champion wrote:
> So, the question seems to me to boil down to whether this 
> needs standardizing, in which case XML seems like the obvious choice, 
> or whether it should remain opaque implementation detail, in which case 
> a URI seems like the obvious choice.

I look at it a bit differently.

The URI is the identification mechanism of the Web, and an EPR is an
identifier.  So from that perspective, I think it's quite clear that an
EPR should be a URI.  The question then, I believe, is whether or not
Web service agents should be peeking into URIs to pull out "reference
properties and parameters".  The TAG has made its view clear on this
question, at least;

"Agents making use of URIs SHOULD NOT attempt to infer properties of
the referenced resource except as specified by relevant specifications."
 -- http://www.w3.org/TR/webarch/#uri-opacity

> IMHO, standardization of this stuff makes sense, even though *at 
> present* the different implementation components that need to exchange 
> routing information tend to be proprietary or custom-written.  After 
> all, you have a bunch of fierce competitors coming to the W3C and 
> saying that they would like to see a Recommendation for this so that 
> they can interoperate better. I'm inclined to give them the benefit of 
> the doubt.

Hmm, I guess I'll be nice and just say "no comment". 8-)

>  Also, at long last we seem to be getting past the 
> "technical" debates that for some inexplicable reason :-) tended to 
> line up on industry alliance boundaries. The absolutely last thing the 
> W3C should do, assuming they want to ever get a web services submission 
> again, is say "thanks, but no thanks, we don't think that needs to be 
> standardized." 

Well, I can see it both ways, but I agree with Bill that they should be
accepted or rejected based on their technical merit.  So far, the W3C
has been doing, IMHO, a very poor job at submission evaluation.

P.S., there's a great example of an EPR in the spec which is just
begging to be a URI;

<wsa:EndpointReference xmlns:wsa="..." xmlns:fabrikam="...">
   <wsa:Address>http://www.fabrikam123.example/acct</wsa:Address>
   <wsa:ReferenceProperties>
       <fabrikam:CustomerKey>123456789</fabrikam:CustomerKey>
   </wsa:ReferenceProperties>
   <wsa:ReferenceParameters>
       <fabrikam:ShoppingCart>ABCDEFG</fabrikam:ShoppingCart>
   </wsa:ReferenceParameters>
</wsa:EndpointReference>

Compare with one of these, or another of your making ...

 http://www.fabrikam123.example/acct?CustomerKey=123456789&ShoppingCart=ABCDEFG
 http://www.fabrikam123.example/acct/123456789?ShoppingCart=ABCDEFG

Mark.