Re: Proposal for WS-Policy assertions - thread 2

Hi Marc 

I have a question and suggestion regarding your/Gilbert's proposal.  I 
didn't want to lose David Hull's other points - hence the separate thread.

** Question: Specifying 'async' only
<wsp:Policy>
   <wsaw:AddressingRequired/>
   <wsaw:NonAnonymousReplies/>
</wsp:Policy>
Indicates all but wsa:anonymous is supported for replies.  How would you 
specify that all URIs except(wsa:anonymous AND wsfoo:anon) are supported 
for replies?

** Suggestion: Specifying full support for WS-Addressing
In the 99% case - namely "I provide complete addressing", your proposed 
solution requires that support for anonymous/non-anon replies is 
explicitly stated.  I.e.
<wsp:Policy>
   <wsaw:AddressingRequired/>
   <wsaw:AnonymousReplies/> 
   <wsfoo:AnonReplies/>
</wsp:Policy>

On a previous note, I mentioned that we should assume that the target 
provides full WS-Addressing support (unless otherwise stated).  In other 
words, the 'anonymous' markers should restrict behaviour, not enhance it.

So, in keeping with the core principle of your suggestion, could we 
restructure the policy assertion so the base case is 'complete support'?
Here's a suggestion:

<wsp:Policy>
   <wsaw:AddressingRequired/>
</wsp:Policy>
means addressing required with *full support* for all replyTo URIs

<wsp:Policy>
  <wsaw:AddressingRequired>
      <wsaw:ResponseURIsRestricted>
         <wsaw:AnonymousReplies/>
         <wsfoo:AnonReplies/>
      </wsaw:ResponseURIsRestricted>
   </wsaw:AddressingRequired>
</wsp:Policy>
means Addressing is required and supported with the restriction that only 
anonymous URIs are supported.

<wsp:Policy>
   <wsaw:AddressingRequired>
       <wsaw:ResponseURIsRestricted>
            <wsaw:NonAnonymousReplies/>
       </wsaw:ResponseURIsRestricted>
    </wsaw:AddressingRequired>
</wsp:Policy>
means Addressing is required and supported with the restriction that only 
non-wsa:anonymous URIs are supported.

Many thanks
Katy




Marc Hadley <Marc.Hadley@Sun.COM> 
Sent by: public-ws-addressing-request@w3.org
08/11/2006 20:50

To
"public-ws-addressing@w3.org List" <public-ws-addressing@w3.org>
cc

Subject
Proposal for WS-Policy assertions






Gilbert and I took an action to propose some assertions for declaring 
WS-Addr requirements/capabilities in WS-Policy. After a bit of 
discussion we came up with the following three assertions:

(i) <wsaw:AddressingRequired/> - the endpoint requires WS-Addressing, 
optionality can be conveyed using WS-Policy constructs.

(ii) <wsaw:AnonymousReplies/> - the endpoint can send replies using 
WS-A anonymous; the endpoint can't send to anon if not present.

(iii) <wsaw:NonAnonymousReplies/> - the endpoint can send replies 
using other addresses; the endpoint can't send to other addresses if 
not present (unless some other assertion adds a class of supported 
addresses).

Assertion (iii) is deliberately vague, its presence means that a non- 
anon address might work but doesn't constrain what such an address 
might look like - a receiver can still reject an address that it 
doesn't grok or that requires a binding it doesn't support. The WG 
decided against specifying things like available response bindings so 
I think this is in line with that decision.

Here are some examples:

<wsp:Policy>
   <wsaw:AddressingRequired/>
   <wsaw:AnonymousReplies/>
</wsp:Policy>

Means that addressing is required and only anonymous replies are
supported.

<wsp:Policy>
   <wsaw:AddressingRequired/>
   <wsaw:NonAnonymousReplies/>
</wsp:Policy>

Means that addressing is required and only non-anonymous replies are
supported.

<wsp:Policy>
   <wsaw:AddressingRequired/>
   <wsaw:AnonymousReplies/>
   <wsaw:NonAnonymousReplies/>
</wsp:Policy>

Means that addressing is required and both anonymous and non-anonymous
replies are supported.

<wsp:Policy>
   <wsaw:AddressingRequired>
</wsp:Policy>

Wouldn't be too useful for anything other than a one-way message 
since neither anonymous nor non-anonymouse replies are supported.

<wsp:Policy>
   <wsaw:AddressingRequired/>
   <wsaw:AnonymousReplies/>
   <wsfoo:AnonReplies/>
</wsp:Policy>

Means that addressing is required and that anon replies as defined by 
WS-Addr or WS-Foo are supported.

Marc.

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