Issue i056 - which messages does the proposal apply to

I took an action on today's call to start a discussion/explore the 
proposal at [1] wrt which WSDL messages the proposal applies to.

The proposal at [2] talks about allowing a wsa:EndpointReference element 
to be included as as child of wsdl20:endpoint or wsdl11:port. When such 
an element is present the value of the [destination] property can be 
determined from the value of the wsa:Address element.

But [destination] is a *Message* Addressing Property and a 
wsdl20:endpoint or wsdl11:port can describe several operation each 
containing multiple 'in' and/or 'out' messages. What this means is that 
the proposal at [1] needs to be specific as to which particular message 
or messages the [destination] value is applicable to.

Issue i056 [2] is about how to determine the value of the [destination] 
property when sending messages *to* a Web service described in WSDL. So 
the issue as recorded is about the 'in' messages and not the 'out' 
messages. Typically, there has to be some mechanism for the service to 
figure out the properties of the 'out' messages including where to send 
it. For example, in an in-out WSDL MEP the 'in' message provides 
information to the service about what the [destination] property value 
of the 'out' message is (the same as the [reply endpoint] of the 'in' 
message). Or in the case of out-only WSDL MEP, there is an issue in 
general as to how the service gets hold of the address where the 'out' 
message is sent (if the SOAP-response MEP is mapped to an out-only WSDL 
MEP, then the HTTP GET message provides these details). So, I don't 
think we need to worry about the value of the [destination] for the 
'out' messages -- as this is client/instance specific and will not be 
described in WSDL. It is the WSDL binding (of WS-Addressing) that would 
specify how the various properties of the 'out' message are filled in 
(per MEP type, see [3]).

Similar to the 'out' messages, I also think that we only need to worry 
about the 'in' message of every operation supported by the 
wsdl20:endpoint/wsdl11:port only if that 'in' message appears as the 1st 
message in the WSDL MEP. This is because the non-first 'in' messages 
depend on the previous message(s) for its properties and the 
WSDL-binding (of WS-Addressing) should specify how those properties get 
filled in.

Comments?

-Anish
--

[1] http://lists.w3.org/Archives/Public/public-ws-addressing/2005Apr/0062
[2] http://www.w3.org/2002/ws/addr/wd-issues/#i056
[3] 
http://dev.w3.org/cvsweb/~checkout~/2004/ws/addressing/ws-addr-wsdl.html?content-type=text/html;%20charset=utf-8#WSDLMEPS

Received on Tuesday, 13 September 2005 02:27:16 UTC