Re: issue 7728: point 1 - proposal for indicating effective endpoint policy in an EPR

Asir,

There is *a* use case is stated in the proposal: "For example, a 
subscriber may wish to indicate to an event source that the notification 
messages sent as part of a subscription must be digitally signed." There 
are many use cases in which one component may send an EPR to another 
component where the binding and portType are implicitly understood; 
wsrm:AcksTo, wse:NotifyTo, wse:EndTo, wsen:EndTo, etc. In general, any 
SOAP implementation of the callback pattern may have need of this 
capability.

- gp

On 10/30/2009 2:07 PM, Asir Vedamuthu wrote:
> We think you meant that a policy expression within a wsa:Metadata element applies to m bindings and n portTypes supported by an endpoint ...
>
> How would a consumer use the policy expression (in an interoperable manner) without any knowledge of one of those m bindings (that usually appear in a WSDL)? Are these known out-of-band?
>
> Regards,
>
> Asir S Vedamuthu
> Microsoft Corporation
>
> -----Original Message-----
> From: ashok malhotra [mailto:ashok.malhotra@oracle.com] 
> Sent: Friday, October 30, 2009 1:10 PM
> To: Asir Vedamuthu
> Cc: Gilbert Pilz; public-ws-resource-access@w3.org; antoine.mensch@odonata.fr
> Subject: Re: issue 7728: point 1 - proposal for indicating effective endpoint policy in an EPR
>
> Hi Asir:
> These would be the policies that applied to the endpoint as a whole i.e. 
> have the endpoint as the policy subject.
> They are not specific to any binding or portType.
> All the best, Ashok
>
>
> Asir Vedamuthu wrote:
>   
>> Then, we do not fully understand the underlying use case. Let’s step 
>> back a bit … How would a consumer use a policy expression within a 
>> wsa:Metadata element in an interoperable manner /without/ any binding 
>> descriptions (that usually appear in a WSDL)?
>>
>>  
>>
>> Regards,
>>
>>  
>>
>> Asir S Vedamuthu
>> Microsoft Corporation
>>
>>  
>>
>> *From:* Gilbert Pilz [mailto:gilbert.pilz@oracle.com]
>> *Sent:* Thursday, October 29, 2009 4:14 PM
>> *To:* Asir Vedamuthu
>> *Cc:* public-ws-resource-access@w3.org; antoine.mensch@odonata.fr
>> *Subject:* Re: issue 7728: point 1 - proposal for indicating effective 
>> endpoint policy in an EPR
>>
>>  
>>
>> From what you described at one of the F2F's (I forget which), the 
>> policies in a MetadataSection with 
>> @Dialect="http://www.w3.org/ns/ws-policy" 
>> <http://www.w3.org/ns/ws-policy> have no specific attachment points or 
>> policy subjects. In the example you provided below, you can't know if 
>> the assertions in the wsp:Policy apply to the endpoint, an operation 
>> of that endpoint, or a particular message; they are just a collection 
>> of policies. If you need to know how/if the policies relate to 
>> messages, operations, or endpoints you need to consult at "other 
>> metadata" like WSDL or PolicyAttachments.
>>
>> The purpose of Section 7.2 is to describe how to "communicate the 
>> effective policies of the endpoints referenced by those EPRs". When 
>> WS-Policy expressions appear as children of wsa:Metadata there is no 
>> uncertainty about how/where these policies apply. "The scope of a 
>> Policy in an EPR is the endpoint referenced by that EPR. The 
>> assertions within the alternatives contained by a Policy in an EPR 
>> MUST have endpoint policy subject." Whereas wsa:Metadata/mex:Metadata 
>> gives you a big blob of metadata that you (the EPR consumer) have to 
>> process (which may include further mex:GetMetadata operations) to 
>> determine the effective policies, wsa:Metadata/wsp:Policy says "this 
>> is the effective policy"; wsa:Metadata/mex:Metadata is general, 
>> wsa:Metadata/wsp:Policy is specific.
>>
>> - gp
>>
>> On 10/28/2009 7:12 PM, Asir Vedamuthu wrote:
>>
>> The underlying use case is addressed by a general-purpose, existing 
>> feature [1][2] in the current WS-MetadataExchange draft. For example,
>>
>>  
>>
>> <wsa:EndpointReference>
>>
>>   <wsa:Address>http://services.example.org/stockquote</wsa:Address>
>>
>>   <wsa:Metadata>
>>
>>    <mex:Metadata>
>>
>>     <mex:MetadataSection>
>>
>>       Dialect='http://www.w3.org/ns/ws-policy'>
>>
>>      <wsp:Policy> ... </wsp:Policy>
>>
>>     </mex:MetadataSection>
>>
>>    </mex:Metadata>
>>
>>   </wsa:Metadata>
>>
>> </wsa:EndpointReference>
>>
>>  
>>
>> Adobe, IBM, Microsoft, Oracle, Sun and WSO2 interop tested [3][4] the 
>> feature in April 2007.
>>
>>  
>>
>> Has anyone analyzed why the existing feature does not address the 
>> underlying use case?
>>
>>  
>>
>> [1] 
>> http://www.w3.org/TR/2009/WD-ws-metadata-exchange-20090924/#Metadata-in-Endpoint-References 
>>
>>
>> [2] http://www.w3.org/Submission/2007/03/Comment
>>
>> [3] 
>> http://www.w3.org/2002/ws/ra/9/01/WS-MetadataExchange-Scenarios-01-19-2007.pdf 
>>
>>
>> [4] 
>> http://www.w3.org/2002/ws/ra/9/01/ws-mex-workshop-minutes-April-2007.pdf  
>>
>>  
>>
>> Regards,
>>
>>  
>>
>> Asir S Vedamuthu
>>
>> Microsoft Corporation
>>
>>  
>>
>> *From:* public-ws-resource-access-request@w3.org 
>> <mailto:public-ws-resource-access-request@w3.org> 
>> [mailto:public-ws-resource-access-request@w3.org] *On Behalf Of 
>> *Gilbert Pilz
>> *Sent:* Wednesday, October 28, 2009 4:34 PM
>> *To:* public-ws-resource-access@w3.org 
>> <mailto:public-ws-resource-access@w3.org>
>> *Cc:* antoine.mensch@odonata.fr <mailto:antoine.mensch@odonata.fr>
>> *Subject:* issue 7728: point 1 - proposal for indicating effective 
>> endpoint policy in an EPR
>>
>>  
>>
>> I've attached the first draft of our proposal for incorporating 
>> WS-PAEPR into WS-Mex [1] to the entry for issue 7728. This is 
>> accomplished by creating a new section, Section 7.2, that describes 
>> what it means to put a wsp:Policy or wsp:PolicyReference in a 
>> wsa:EndpointReference/wsa:Metadata element.
>>
>> Note this addresses the WS-DD comments ([2], [3]) made on 
>> WS-MetadataExchange by Antoine Mensch.
>>
>> [1] http://www.w3.org/Bugs/Public/attachment.cgi?id=775
>> [2] 
>> http://lists.w3.org/Archives/Public/public-ws-resource-access/2009Oct/0027.html
>> [3] 
>> http://lists.w3.org/Archives/Public/public-ws-resource-access/2009Oct/0033.html\ 
>> <http://lists.w3.org/Archives/Public/public-ws-resource-access/2009Oct/0033.html>
>>
>> - gp
>>
>>     
>
>