W3C home > Mailing lists > Public > public-ws-addressing@w3.org > November 2004

Re: i028: Implications of the presence of ReplyTo

From: Tom Rutt <tom@coastin.com>
Date: Fri, 12 Nov 2004 09:22:55 -0800
Message-ID: <4194F16F.6040703@coastin.com>
To: Martin Gudgin <mgudgin@microsoft.com>
CC: Marc Hadley <Marc.Hadley@sun.com>, public-ws-addressing@w3.org



Martin Gudgin wrote:

> 
>
>  
>
>>-----Original Message-----
>>From: Tom Rutt [mailto:tom@coastin.com] 
>>Sent: 12 November 2004 17:02
>>To: Marc Hadley
>>Cc: Martin Gudgin; public-ws-addressing@w3.org
>>Subject: Re: i028: Implications of the presence of ReplyTo
>>
>>    
>>
>>Also, if there is no need for transport independence, the 
>>message should 
>>not have to send wsa:reply to when a wsdl request/response is bound
>>to a request/response transport (e.g., soap http/post binding).   
>>    
>>
>
>How does the crafter of a message determine whether there is a need for
>transport independence or not? I might be adding WS-Addressing headers
>to a message at a layer that is unaware of the binding in use. And the
>layer processing the WS-Addressing headers on the receiver side might
>not know what binding the message came in on. 
>  
>
I am speaking of an environment where the flexibility of EPRs is 
desired, but the day to day
infrastructure in use is in an exclusively soap/httpPost environment.  
As an optimization, the sender may know
the environment it is using, and does not need to send stuff that is 
unnecessary.

>  
>
>>I 
>>would say wsa:replyTo is only required to be send when the request / 
>>response
>>is bound to a one way underlying transport.
>>    
>>
>
>I really believe this would be a mistake. I really want a world where
>the set of headers is NOT dependant on *how* the message is transmitted
>( or how some future message will be transmitted ).
>  
>
I want a world where extraneous stuff not needed for a particular 
application of WS:addressing must be sent.

Some Fujtisu product people desire the ability to optimize and tune for 
performance in tighly constrainted infrastructure
environments.


>Gudge
>
>  
>
>>Tom Rutt
>>
>>Marc Hadley wrote:
>>
>>    
>>
>>>On Nov 12, 2004, at 6:08 AM, Martin Gudgin wrote:
>>>
>>>      
>>>
>>>>>On Nov 11, 2004, at 3:01 PM, Martin Gudgin wrote:
>>>>>
>>>>>          
>>>>>
>>>>>>>So it sounds like you'd be in favor of saying that presence
>>>>>>>of ReplyTo
>>>>>>>implies a request is expected and that absence 
>>>>>>>              
>>>>>>>
>>indicates a one-way
>>    
>>
>>>>>>>message ?
>>>>>>>              
>>>>>>>
>>>>>>Nope. I think that if you expect a reply, you MUST specify [reply
>>>>>>endpoint]. So in request-response style MEPs [reply 
>>>>>>            
>>>>>>
>>endpoint] would
>>    
>>
>>>>>>always be specified in the request message. However, I
>>>>>>            
>>>>>>
>>>>>don't think that
>>>>>
>>>>>          
>>>>>
>>>>>>specifying [reply endpoint] necessarily means you expect 
>>>>>>            
>>>>>>
>>a reply (in
>>    
>>
>>>>>>request/response stylee). Does that make sense. I'm saying
>>>>>>
>>>>>>    if a then b
>>>>>>
>>>>>>but I'm NOT saying
>>>>>>
>>>>>>    if b then a
>>>>>>
>>>>>>            
>>>>>>
>>>>>I understand what you mean but I'm not sure it makes 
>>>>>          
>>>>>
>>sense ;-). If we
>>    
>>
>>>>>could say that presence of ReplyTo indicates that a reply 
>>>>>          
>>>>>
>>is expected
>>    
>>
>>>>>then that would seem like a useful semantic. What's the 
>>>>>          
>>>>>
>>purpose of a
>>    
>>
>>>>>ReplyTo in a message that isn't expected to generate a reply ?
>>>>>          
>>>>>
>>>>OK, it depends on what you mean when you say 'generate a 
>>>>        
>>>>
>>reply'. Do you
>>    
>>
>>>>mean
>>>>
>>>>a) 'generate a reply as part of the same WSDL MEP'
>>>>
>>>>        
>>>>
>>>Yes.
>>>
>>>      
>>>
>>>>b) 'generate a reply, not necessarily part of the same WSDL MEP'
>>>>
>>>>I have certain protocols that do specify a [reply 
>>>>        
>>>>
>>endpoint], do expect
>>    
>>
>>>>(hope?) that a reply to be sent at some point, but NOT as 
>>>>        
>>>>
>>part of the
>>    
>>
>>>>same WSDL operation as the initial message.
>>>>
>>>>        
>>>>
>>>That's the kind of scenario I was getting it when I raised 
>>>      
>>>
>>issue i015 
>>    
>>
>>>about redirection. E.g. if a responder in a request 
>>>      
>>>
>>response MEP sends 
>>    
>>
>>>back a ReplyTo header, do we expect that to apply to subsequent 
>>>interactions between the requester and responder. I.e. what is the 
>>>scope of the effect of a ReplyTo, is it scoped to an instance of a 
>>>particular MEP or something wider ? Till now I'd been assuming the 
>>>former, are you suggesting it should be the latter ?
>>>
>>>Cheers,
>>>Marc.
>>>
>>>---
>>>Marc Hadley <marc.hadley at sun.com>
>>>Web Technologies and Standards, Sun Microsystems.
>>>
>>>
>>>      
>>>
>>-- 
>>----------------------------------------------------
>>Tom Rutt	email: tom@coastin.com; trutt@us.fujitsu.com
>>Tel: +1 732 801 5744          Fax: +1 732 774 5133
>>
>>
>>
>>    
>>
>
>  
>

-- 
----------------------------------------------------
Tom Rutt	email: tom@coastin.com; trutt@us.fujitsu.com
Tel: +1 732 801 5744          Fax: +1 732 774 5133
Received on Friday, 12 November 2004 17:25:04 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Tuesday, 2 June 2009 18:34:59 GMT