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Re: New issue: Default value of To property

From: Marc Hadley <Marc.Hadley@Sun.COM>
Date: Tue, 24 Jan 2006 11:07:12 -0500
To: Francisco Curbera <curbera@us.ibm.com>
Cc: Mark Nottingham <mnot@mnot.net>, WS-Addressing <public-ws-addressing@w3.org>, public-ws-addressing-request@w3.org
Message-id: <B591697D-0045-4661-9A62-2BFAB58E3218@Sun.COM>
I think it complicates things to have a default in some circumstances  
and not others. Provided the default value is always the same  
(anonymous in our case), it is easy to formulate the value of MAPs  
and check the validity of an inbound message regardless of whether  
the message is a request, response, notification, fault or some other  
classification that we haven't yet come up with. If we start adding  
provisos to the defaulting rules then things just get more complex  
and we'll end up introducing edge cases etc.

To be honest I'm not clear what problem you are trying to solve, why  
is it better to have an explicit <wsa:To>http://.../../anonymous</ 
wsa:To> in the message than an implicit default one ?

FWIW, I can see that having an anonymous wsa:To in a request message  
might cause some implementations difficulties, but changing the  
defaulting rules won't fix this problem (you could still get an  
explicit anonymous to) and as I outlined in my previous mail its  
unlikely to occur in the first place. If an anonymous wsa:To in  
request messages is the problem you are trying to attack then I think  
it would be much more effective to work on that directly rather than  
complicating the defaulting rules.

Marc.

On Jan 24, 2006, at 10:24 AM, Francisco Curbera wrote:

> Hi Marc,
>
> You are taking the sender's view only; there is also the receiver's  
> view,
> who may or may not have access to the EPR the sender used. In any  
> case, it
> is clear that any default works as long as it is not ambiguous.  
> What I am
> arguing is that a default only makes sense when it cover (and maybe  
> helps
> optimize) a common case. It can certainly be argued that for  
> synchronous
> request response interactions it makes sense to default the To of  
> the reply
> message to anonymous. Arguing that that is also the case for all  
> other uses
> of WSA is to take a very narrow perspective IMO - particularly  
> since one of
> WSA's major contributions is  to enable interoperable asynchronous
> messaging over different interaction patterns.
>
> We essentially went through a similar argument when we recognized that
> defaulting the [reply endpoint] to an EPR with an anonymous address  
> makes
> sense only in the context of Section 3.4 - Formulating a Reply  
> Message. I
> think we just need to finish the job and scope the defaulting of the
> [destination] property to anonymous to the case of reply messages  
> as well.
>
> Paco
>
>
>
>
>
>                       Marc Hadley
>                       <Marc.Hadley@Sun.COM>           To:        
> Francisco Curbera/Watson/IBM@IBMUS
>                       Sent by:                        cc:        
> Mark Nottingham <mnot@mnot.net>, WS-Addressing
>                       public-ws-addressing-req         <public-ws- 
> addressing@w3.org>
>                       uest@w3.org                     Subject:  Re:  
> New issue: Default value of To property
>
>
>                       01/23/2006 10:50 AM
>
>
>
>
>
> I don't think we need to special-case things as you suggest since the
> rules for sending a message[1] already require the wsa:To to have the
> same address as that contained in the EPR to which the message is
> sent. Therefore the only time the wsa:To value can be defaulted is
> when the EPR to which the message is sent has an 'anonymous' address
> and I don't see that happening regularly with request messages
> because, if it did, you wouldn't know where to send then.
>
> Marc.
>
> [1] http://dev.w3.org/cvsweb/~checkout~/2004/ws/addressing/ws-addr-
> core.html?content-type=text/html;%20charset=utf-8#sendmsgepr
>
>
> On Jan 20, 2006, at 1:23 PM, Francisco Curbera wrote:
>
>>
>> Can I please add this new CR issue against the WS-Addressing core
>> spec.
>>
>> The spec currently defaults the value of the To property to anonymous
>> (Core, 3.2); the goal of this decision was to optimize the request
>> reply
>> synchronous interaction. However, as written in Section 3.2 this
>> applies to
>> arbitrary messages. Just as in the case of ReplyTo, addressed in
>> CR13, I
>> propose the defaulting of To to anonymous be moved to Section 3.4 and
>> limited to request reply interactions.
>>
>> Paco
>>
>>
>
> ---
> Marc Hadley <marc.hadley at sun.com>
> Business Alliances, CTO Office, Sun Microsystems.
>
>
>
>
>
> #### smime.p7s has been removed from this note on January 24, 2006 by
> Francisco Curbera
> <smime.p7s>

---
Marc Hadley <marc.hadley at sun.com>
Business Alliances, CTO Office, Sun Microsystems.




Received on Tuesday, 24 January 2006 16:07:20 GMT

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