- From: Yalcinalp, Umit <umit.yalcinalp@sap.com>
- Date: Tue, 16 Jan 2007 09:14:22 -0800
- To: "Asir Vedamuthu" <asirveda@microsoft.com>, <public-ws-policy@w3.org>
- Message-ID: <2BA6015847F82645A9BB31C7F9D6416503241892@uspale20.pal.sap.corp>
I am glad at least we agree that is the expected semantics. I guess what we do not agree is the explicitness of the rule 4 to get there. --umit ________________________________ From: public-ws-policy-request@w3.org [mailto:public-ws-policy-request@w3.org] On Behalf Of Asir Vedamuthu Sent: Monday, Jan 15, 2007 11:51 PM To: Yalcinalp, Umit; public-ws-policy@w3.org Subject: RE: NEW ISSUE 4138: Normalization Algorithm is broken >"what is the expected result" <Policy> <ExactlyOne> <All> <wsap:UsingAddressing/> </All> </ExactlyOne> </Policy> How to get there? Rule 4 applies. The Policy operator is equivalent to All. That is, '<All><wsap:UsingAddressing/></All>'. This is a policy alternative with one assertion. Construct a normal form as per Section 4.1 = the above result. I hope this helps. Regards, Asir S Vedamuthu Microsoft Corporation From: public-ws-policy-request@w3.org [mailto:public-ws-policy-request@w3.org] On Behalf Of Yalcinalp, Umit Sent: Monday, January 15, 2007 10:36 AM To: Asir Vedamuthu; public-ws-policy@w3.org Subject: RE: NEW ISSUE 4138: Normalization Algorithm is broken Asir, Instead of thinking of "what is the minimum change", I would like to approach it as to "what is the expected result" first and then find out how we can achieve it. Could you tell me first what the normalized form of <wsp:Policy> <wsap:UsingAddressing/> </wsp:Policy> is? Lets go from there. "Construct a normal form" for this does not really follow and indicate what the result should be. Thanks, --umit ________________________________ From: Asir Vedamuthu [mailto:asirveda@microsoft.com] Sent: Sunday, Jan 14, 2007 10:59 PM To: Yalcinalp, Umit; public-ws-policy@w3.org Subject: RE: NEW ISSUE 4138: Normalization Algorithm is broken >Thus, readers following the Framework with >the primer document and trying to formulate >a normal form will not be able to get what >they want. First, thank you for carefully reviewing the normalization algorithm and manually working out an example (this is equivalent to running a unit test). We looked into interop test cases. There are many test cases that use the form <Policy><wsap:UsingAddressing /></Policy> in the contributed interop scenarios pack [1]. Several implementers ran these test cases. The good news is that there aren't any related interop issues. Framework document says [2], "4. Apply the policy operator indicated by D to the normalized Element Information Items in its [children] property and construct a normal form per Section 4.3.3 Policy Operators." In the above sentence, 'construct a normal form' is the key phrase and it refers to the normal form in Section 4.1 [3]. Section 4.1 XML outline and prose describe how a policy alternative in the normal form looks like. To help readers make this connection, we suggest that the normalization algorithm carry an explicit reference to the normal form. This means, the proposed change is: s/4. Apply the policy operator indicated by D to the normalized Element Information Items in its [children] property and construct a normal form per Section 4.3.3 Policy Operators./4. Apply the policy operator indicated by D to the normalized Element Information Items in its [children] property and construct a normal form per Section 4.3.3 Policy Operators and 4.1 Normal Form Policy Expression./ We belive that the above proposed change is the minimum needed to resolve issue 4138 [4]. [1] http://lists.w3.org/Archives/Public/public-ws-policy/2006Jun/0010.html <http://lists.w3.org/Archives/Public/public-ws-policy/2006Jun/0010.html> [2] http://www.w3.org/TR/2006/WD-ws-policy-20061117/#Compact_Policy_Expressi on <http://www.w3.org/TR/2006/WD-ws-policy-20061117/#Compact_Policy_Express ion> [3] http://www.w3.org/TR/2006/WD-ws-policy-20061117/#Normal_Form_Policy_Expr ession <http://www.w3.org/TR/2006/WD-ws-policy-20061117/#Normal_Form_Policy_Exp ression> [4] http://www.w3.org/Bugs/Public/show_bug.cgi?id=4138 <http://www.w3.org/Bugs/Public/show_bug.cgi?id=4138> Regards, Asir S Vedamuthu Microsoft Corporation From: public-ws-policy-request@w3.org [mailto:public-ws-policy-request@w3.org] On Behalf Of Yalcinalp, Umit Sent: Tuesday, January 02, 2007 11:58 AM To: public-ws-policy@w3.org Subject: NEW ISSUE: Normalization Algorithm is broken Title: Normalization Algorithm is broken Description: The Normalization Algorithm in the WS-Policy framework is broken in converting a single expression of conjuncts in compact form to an equivalent expression normal form and does not lead to a normal form expression as illustrated below. For expressions of the following form where the wsp:Policy element may have single element child, or a multiple element children composition with wsp:All such as: <wsp:Policy> <ex:Assertion1/> </wsp:Policy> or <wsp:Policy> <wsp:All> <ex:Assertion1/> <ex:Assertion2/> </wsp:All> </wsp:Policy> The normalization algorithm fails to convert this into an equivalent expression. It would be expected to derive a normal form expression with a single alternative of the form from such expressions. <wsp:Policy> <wsp:ExactlyOne> <wsp:All> List of Assertions </wsp:All> </wsp:ExactlyOne> </wsp:Policy> but the algorithm fails to do so. In both cases, there is no wsp:optional attribute to introduce two alternatives into the resulting expression converted to the normal form. Thus, no wsp:exactlyOne is introduced in this case, and the resulting expression can not be normalized. Note that the primer [1] uses such an example for the use of WS-Addressing in Example 2.2. Thus, readers following the Framework with the primer document and trying to formulate a normal form will not be able to get what they want. I will illustrate the result using the following example: <Policy> <wsap:UsingAddressing /> </Policy> Taking the first form (a single child element) as an example, here is the rundown of the normalization algorithm: 1. Start with the [document element] property D of the Document Information Item of the policy expression. The [namespace name] of D is always "http://www.w3.org/2006/07/ws-policy <http://www.w3.org/2006/07/ws-policy> ". In the base case, the [local name] property of D is "Policy"; in the recursive case, the [local name] property of D is "Policy", "ExactlyOne", or "All". 2. Expand Element Information Items in the [children] property of D that are policy references per Section 4.3.5 Policy Inclusion <file:///\\l%20> . 3. Convert each Element Information Item C in the [children] property of D into normal form. 1. If the [namespace name] property of C is "http://www.w3.org/2006/07/ws-policy <http://www.w3.org/2006/07/ws-policy> " and the [local name] property of C is "Policy", "ExactlyOne", or "All", C is an expression of a policy operator; normalize C by recursively applying this procedure. 2. Otherwise the Element Information Item C is an assertion; normalize C per Sections 4.3.1 Optional Policy Assertions <file:///\\l%20> and 4.3.2 Policy Assertion Nesting <file:///\\l%20> . 4. Apply the policy operator indicated by D to the normalized Element Information Items in its [children] property and construct a normal form per Section 4.3.3 Policy Operators <file:///\\l%20> . Here is what happens if you follow this step by step. 1. applies <wsp:Policy> 2. does not apply 3. The element information item C is wsap:UsingAddressing. 4. does not apply 5. there is nothing to normalize (as 4.3.1, or 4.3.2 does not apply) 6. The policy operator indicated by D is wsp:Policy which is equivant to "wsp:All" "Applying" wsp:All to wsaw:UsingAddressing is <wsp:All><wsaw:UsingAddressing/></wsp:All> There is no optional assertion, etc. Thus, <wsp:exactlyOne> is not introduced anywhere per the rules of the algorithm. The resulting Expression is <wsp:All><wsaw:UsingAddressing/></wsp:All> This is not in normal form!!! It is noted that it is impossible to convert an assertion which does not have an wsp:optional attribute to a normal form. This appears to be a deficiency of the algorithm, and not its intention. This is a bug in the framework. Justification: A common form of the expression is expected to work without the presence of wsp:optional attribute. It is possible to create such expressions using the policy framework. As a matter of fact, the example is from our own primer document itself. The algorithm should work for simple cases when single alternatives are intended by compact form as well as complicated cases where alternatives are introduced by the presence of the wsp:optional attribute implicitly. The algoritm should not assume the presence of wsp:optional to introduce alternatives. Proposal: Add another step for the normalization algorithm along the lines of 7. If the resulting expression contains no alternatives, the expression is equivalent to a policy with a single alternative where the content of the resulting expression comprises its content. This issue is filed as [Bug 4138] with the content that is provided above. [1] http://www.w3.org/TR/2006/WD-ws-policy-primer-20061018/ <http://www.w3.org/TR/2006/WD-ws-policy-primer-20061018/> [Bug 4138] http://www.w3.org/Bugs/Public/show_bug.cgi?id=4138 <http://www.w3.org/Bugs/Public/show_bug.cgi?id=4138> ---------------------- Dr. Umit Yalcinalp Research Scientist SAP Labs, LLC Email: umit.yalcinalp@sap.com Tel: (650) 320-3095 SDN: https://www.sdn.sap.com/irj/sdn/weblogs?blog=/pub/u/36238 <https://www.sdn.sap.com/irj/sdn/weblogs?blog=/pub/u/36238> -------- "Nearly all men can stand adversity, but if you want to test a man's character, give him power." Abraham Lincoln.
Received on Tuesday, 16 January 2007 17:13:04 UTC