Re: Issue i048 - summary of discussion

+1 to Hugo's comments and to either sticking with the status quo or 
going with option 2. BTW, I didn't think anyone was suggesting that 
EPRs with the same [address] were interchangeable, just that they 
referred to the same endpoint - the current text doesn't suggest 
anything about interchangeability to me.

Marc.

On Feb 21, 2005, at 4:55 PM, Hugo Haas wrote:

>
> Hi Umit.
>
> * Yalcinalp, Umit <umit.yalcinalp@sap.com> [2005-02-21 08:14+0100]
>> Here is my take on this matter, followed by a proposal.
>>
>> Issue:
>>
>> I would like to look at this problem of what we are gaining by 
>> providing
>> a comparison of endpoint references. From a client's perspective, the
>> comparison of endpoints may only be useful if the comparison were to
>> indicate interchangeability. This means that given two EPRs, a client
>> could toss away one of them iff they are determined to be the same,
>> meaning indistinguishable for all practical purposes.
>
> I don't think that the purpose of comparing EPRs is
> interchangeability. It has been expressed several times in the context
> of issues i001 and i014  in particular, see discussion at [11]  that
> its goal was metadata caching, and section 2.3 does exactly this: it
> tells you, if you have an EPR and some metadata for it, what you can
> conclude about the metadata when you receive another EPR.
>
> I will discuss this issue from this angle to avoid the sensitive
> I-word.
>
> [..]
>> I can give more examples, but I do hope you get the idea. In all these
>> cases above, however, we can safely determine whether two EPRs refer 
>> to
>> the same endpoint by comparing their addresses.
>
> I believe that this is what section 2.3 does: it points out that
> [address] is the cache key.
>
> [..]
>> Proposal:
>>
>> I believe that the current status quo is really harmful and misleading
>> for all purposes. I will be strongly against the status quo and 
>> closing
>> the issue.
>>
>> There are three different things we can do:
>>
>> (1) Remove Section 2.3 and clean up the confusion we have created as
>> proposed by Paco.
>> (2) Change 2.3 to make it consistent with the resolution of Issue 20 
>> iv,
>> by illustrating that EPRs are not interchangeable and by clarifying 
>> how
>> they refer to the same endpoint that use the same metadata.
>> (3) Add capability for endpoints to determine whether two EPRs are the
>> indeed interchangeable.
>>
>> Lets look at the details:
>>
>> Proposal for (2)
>>
>> Per [6], a gateway configuration can be considered to be endowed with
>> the union of all the metadata of all services that share that address.
>> However the following section is misleading for this as it is
>> inconsistent with the decision we just made [8].
>>
>> {The following rule clarifies the relation between the behaviors of 
>> the
>> endpoints represented by two endpoint references with the same
>> [address];
>> - The two endpoints accept the same sets of messages, and follow and
>> require the same set of policies. That is, the XML Schema, WSDL, and
>> policy and other metadata applicable to the two references are the
>> same.}
>>
>> Instead it should be corrected to say:
>>
>> {The following rule clarifies the relation between the behaviors of 
>> the
>> endpoints represented by two endpoint references with the same
>> [address];
>> - The two endpoint references refer to the same endpoint that accepts 
>> a
>> set of messages, follow and require a set of policies that are defined
>> by a (set of) XML Schema(s), WSDL(s), and policies and other metadata
>> applicable. Hence, these endpoint references are designed to utilize 
>> the
>> set of messages, policies and descriptions that apply to the specific
>> endpoint.
>> }
> [..]
>
> I am fine with the status quo, but I think that I am also happy with
> your proposal 2 which keeps the spirit of section 2.3.
>
> I believe that proposal (1) goes against the resolution of i001, and
> that proposal (3) brings us back to the area of formal identifiers for
> which the WG has decided against already.
>
> Cheers,
>
> Hugo
>
>   11. 
> http://www.w3.org/2002/ws/addr/4/12/13-ws-addr-minutes.html#item05
> -- 
> Hugo Haas - W3C
> mailto:hugo@w3.org - http://www.w3.org/People/Hugo/
>
>
---
Marc Hadley <marc.hadley at sun.com>
Web Technologies and Standards, Sun Microsystems.

Received on Tuesday, 22 February 2005 17:21:34 UTC