Re: [Bug 6721] New: Attaching policy to implicit operations

Hi Ashok,

I agree that it should be possible to pass the policy in the EPR. However, 
this isn't quite answering this issue because it doesn't give a syntax for 
attaching the policy to the implicit operation (as the scope of the policy 
in the EPR metadata is the endpoint).  We could state that the implicit 
operations simply inherit the endpoint's policy but this approach has 
drawbacks (as mentioned in the issue).

Theoretically, implicit operations' policies could be passed in WSDL or 
EPR (and it would be nice to allow both), but in both cases we'd need a 
way to indicate that the policy is associated with the implicit operation 
(rather than the endpoint and all its operations).

Incidentally, the WS-Mex GetMetadata verb adds an additional complexity to 
the implicit operation problem because there is a chicken-egg situation 
that means that there's no way to get the WSDL:  
http://www.w3.org/Bugs/Public/show_bug.cgi?id=6463.  Passing policy in the 
EPR could be a solution to this problem ... but there is still the 
question as to how to associate the policy with the actual GetMetadata 
operation.

Best regards, 
Katy



From:
ashok malhotra <ashok.malhotra@oracle.com>
To:
"public-ws-resource-access@w3.org" <public-ws-resource-access@w3.org>
Date:
19/03/2009 18:59
Subject:
Re: [Bug 6721] New: Attaching policy to implicit operations



Our proposal for attaching policy to endpoints is to include it in the 
metadata section of the EPR.
See http://www.w3.org/Submission/WS-PAEPR
All the best, Ashok


bugzilla@farnsworth.w3.org wrote:
> http://www.w3.org/Bugs/Public/show_bug.cgi?id=6721
>
>            Summary: Attaching policy to implicit operations
>            Product: WS-Resource Access
>            Version: PR
>           Platform: PC
>         OS/Version: Windows XP
>             Status: NEW
>           Severity: normal
>           Priority: P2
>          Component: All
>         AssignedTo: public-ws-resource-access-notifications@w3.org
>         ReportedBy: katy_warr@uk.ibm.com
>          QAContact: public-ws-resource-access-notifications@w3.org
>
>
> There are a number of issues already open addressing how we attach 
policies to
> indicate that an endpoint supports virtual (implicit) operations and the
> flavour/extent of that support.  For example,issue 6403
> http://www.w3.org/Bugs/Public/show_bug.cgi?id=6403 describes policy to 
indicate
> that an endpoint supports enumeration and there are similar issues open 
for the
> other specs (6402,6406, 6407).
>
> These issues do not discuss how policy should be attached to the virtual
> operation (i.e. one that does not appear in WSDL) itself.  They also 
don't
> address what policy should be applied to the virtual operations by 
default. 
> One option for default behaviour might be to default to the policy of 
the
> endpoint, but this poses problems as many policies are applied at
> operation/message level (and therefore are not available at the 
endpoint).
>
> There are a number of possible solutions that we might adopt to solve 
this
> problem.  I suggest that we choose a pattern and re-use that across all 
the
> specs for simplicity and consistency.
>
> For example, here's a potential pattern:
>
> <wsp:Policy>
>    ... <lots of policy for the endpoint>
>
>    <wsra policy indicating wsra spec support>
>       ...
>
>       <wsra:VirtualOperationPolicy>
>           ...
>       </wsra:VirtualOperationPolicy> 
>
>    </wsra policy indicating wsra spec support>
>
> </wsp:Policy>
>
> The VirtualOperationPolicy defines the policy for the implicit 
operations
> relating to the wsra spec support.
>
> For example, the above pattern applied to eventing MIGHT look something 
like
> this:
>
> <wsev:WSEventingSupported  ...>
>   <wsp:Policy>
>     ...
>
>     <wsev:subscribeOperationPolicy>
>         ... policies such as security policy to attach to subscribe 
request ...
>     </wsev:subscribeOperationPolicy>
>
>   </wsp:Policy>
> </wsev:WSEventingSupported>
>
> If we agree on a pattern to try, the next step might be to take some 
real
> examples (e.g. security policy) in order to check that the pattern works 
prior
> to applying it across the specs.
>
> This issue is also related to
> http://www.w3.org/Bugs/Public/show_bug.cgi?id=6694 which asks when 
operations
> do/don't appear in the WSDL. 
>
> It's probably best for us to address the other policy issues and 6694 
before
> this one - but this is an important issue as lack of clear specification 
in
> this area will prevent interoperability and make life hard for 
implementers.
>
>
> 









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