OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.

 


Help: OASIS Mailing Lists Help | MarkMail Help

sca-policy message

[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]


Subject: Re: [sca-policy] ISSUE-95: Calculation of the Required Intent Set for anElement has a Flaw


http://www.osoa.org/jira/browse/POLICY-95

Dave Booz
STSM, BPM and SCA Architecture
Co-Chair OASIS SCA-Policy TC and SCA-J TC
"Distributed objects first, then world hunger"
Poughkeepsie, NY (845)-435-6093 or 8-295-6093
e-mail:booz@us.ibm.com

Inactive hide details for Mike Edwards ---06/26/2009 04:41:04 AM---Raiser:         Mike Edwards Target:         CD02 of the PolMike Edwards ---06/26/2009 04:41:04 AM---Raiser: Mike Edwards Target: CD02 of the Policy Spec: sca-policy-1.1-spec-cd02.pdf


From:

Mike Edwards <mike_edwards@uk.ibm.com>

To:

"OASIS Policy" <sca-policy@lists.oasis-open.org>

Date:

06/26/2009 04:41 AM

Subject:

[sca-policy] [NEW ISSUE] Calculation of the Required Intent Set for an Element has a Flaw






Raiser: Mike Edwards

Target: CD02 of the Policy Spec: sca-policy-1.1-spec-cd02.pdf

Description:
** Raised as a result of an action item from the SCA Bindings TC ***

In Section 4.12.1 of the Policy spec, there is a definition of the required intent set for an element

This definition has a flaw that causes problems for some specific use cases of intents. It was revealed
when considering the SOAP intent applying to the Web services binding, with its qualified forms
SOAP.1_1 and SOAP.1_2.

The flaw concerns the last item in the list of the definition - item 7 - which reads:

1162 7. and where any unqualified qualifiable intents are replaced with the default qualified form of that
1163 intent, according to the default qualifier in the definition of the intent

This step implies that any unqualified form of a qualifiable intent in the required intent set is taken to mean the
qualified form using the default qualifier, come what may.

In the case of the SOAP intents, this would mean that "SOAP" would be synonymous with "SOAP.1_1" and
thus it would NEVER be possible to satisfy @requires="SOAP" with a policy that provided the SOAP.1_2
qualified form of the intent.

This is clearly NOT the basic idea behind qualifiable intents. In this example, "SOAP" is intended to mean

"The SOAP protocol must be used, but it does not matter which version of SOAP is used"

it is *NOT* intended to mean "The SOAP 1.1 protocol must be used"

The original purpose of the default qualifier was to guide policy selection so that IN THE ABSENCE OF ANY
OTHER INFORMATION, the unqualified form of a qualifiable intent could be mapped to a qualified form
using the default qualifier.

However, the presence of other information, such as a PolicySet which provides "SOAP" and deliberately
maps it to "SOAP.1_2", should be valid and should work.

Thus the current definition of the required intent set does not achieve the original goals of intents and should be
modified accordingly.


Proposal:

Remove item 7 from the definition of the required intent set.

This means that the required intent set CAN contain the unqualified form of a qualifiable intent.
This unqualified form can be then interpreted by bindings and policySets in a way that is appropriate to their
configuration, with the use of the default qualifier being a clause useful in the case where the binding or the
policySet has no other means to choose which qualifier to apply for the unqualified form of the intent.

I note that both the qualified and the unqualified forms of an intent are fully discussed later in section 4.12.1
in relation to both bindings and in relation to policySets.


Yours, Mike.

Strategist - Emerging Technologies, SCA & SDO.
Co Chair OASIS SCA Assembly TC.
IBM Hursley Park, Mail Point 146, Winchester, SO21 2JN, Great Britain.
Phone & FAX: +44-1962-818014 Mobile: +44-7802-467431
Email: mike_edwards@uk.ibm.com




Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number 741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU







[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]