Re: [ws-rx] An alternative approach to make anon reply-to and sync rmwork

[Tom Rutt <tom@coastin.com>]

Paul Fremantle wrote:

> Doug
>
> The use of this model by the client is optional.

Whenever we figure this scenario out, it would be nice to have a way for 
people not part of this discussion to
learn how to use ws-rx for the scenario.

Such guidance can go into an applicaiton notes document, which is 
progressed in parralel, perhaps just to CD level (i.e., no OASIS vote).

The way ws-rx binds to http for the typical web service wsdl use cases 
should be clear to implementors.  While such "guidance" is not
warranted in a specifiction, it would be useful to have as an auxilliary 
document.

WS-RF has such a document.

Tom Rutt

>
> So two possibilities.
>
> 1) The client needs to use the HTTP connection as the correlator. In 
> this case it can either keep replaying the request message, or *just 
> not use this model*.
> 2) The client can use the relatesTo header as the correlator (and the 
> client RMS/RMD) doesn't span multiple endpoints. In this case it 
> works. If the client's RMS/RMD spans multiple endpoints, then the 
> choice is there to *just not use this model*. Its optional.
>
> Paul
>
>
>
> Doug Davis wrote:
>
>>
>> Paul,
>>
>> I think there are some problems with this - I still think this 
>> violates WSA.  There's a reason anon replyTo means, in essence, the 
>> http response flow of the request message.  The connection becomes 
>> the correlator between the request and the response - meaning if 
>> several anon requests come in the only way the server knows which 
>> client gets which response is thru the http connection.  In your 
>> scenario if there are two anon requests sent to the server using the 
>> same sequence and no responses sent, when the third connection is 
>> made (to carry the ackReq) how does the server know which client is 
>> initiating the request.  It can not simply assume that just because 
>> they shared the same sequence that they also share WSA state and that 
>> any response can be sent to any client.  The correlation is now lost. 
>> thanks,
>> -Doug
>


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