Re: Reference Parameters - using them

On Sep 28, 2005, at 7:35 PM, Pete Hendry wrote:
>
> Related to David's examples for i057, I was wondering about what I  
> would consider the most common use-case for reference parameters -  
> the server wanting the client to return context in the next  
> request. It seems to me the current design of reference parameters  
> are only useful for
>
> a) fixed value data - i.e. not session-like data
> b) the client asking the server to pass back information using the  
> replyTo header
>
> Consider the (common?) scenario where a client logs into a server.  
> The server then creates a "session" in which it has customerKey and  
> shoppingCartId values it wants the client to pass back in each  
> subsequent request. These are opaque as the client does not have to  
> know what the customerId or shoppingCartId are to work, it just has  
> to include them as-is. ReferenceParameters seem the ideal vehicle  
> for this but where would the server specify these parameters?

This is the kind of use case I had in mind when I raised issue 15[1],  
the group didn't want to go there and we settled on pointing to WS- 
Context instead[2]. Mebbe we need to add something to the  
specification along these lines rather than just in the issue  
resolution in the issues list ?

Marc.

[1] http://www.w3.org/2002/ws/addr/wd-issues/#i015
[2] http://lists.w3.org/Archives/Public/public-ws-addressing/2005Jan/ 
0180


> They are not fixed values and will change for each "conversation"  
> so they cannot just be specified in the WSDL with fixed values.  
> They have to be parameterized somehow to allow the server to set  
> the actual session values and pass them to the client to be  
> included in the next request.
>
> Is this beyond the scope of reference parameters? In (my  
> understanding of) their current form they are of little use. It is  
> unlikely you would want to publish fixed values within parameters  
> in WSDL (or any other static mechanism) and less likely that the  
> client would start the session information that could be contained  
> within them.
>
> Pete
>
>

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