RE: [Bug 8196] New: inheriting enveloping namespace prefixes is dangerous

Thanks for the note. We understand the challenges involved in composing (and serializing) such SOAP messages and designing user-friendly APIs. But there aren't any technical reasons to carry those challenges or [in-scope namespaces] in wire-level messages.

Regards,

Asir S Vedamuthu
Microsoft Corporation

From: Gilbert Pilz [mailto:gilbert.pilz@oracle.com]
Sent: Wednesday, November 04, 2009 8:02 PM
To: Asir Vedamuthu
Cc: public-ws-resource-access@w3.org
Subject: Re: [Bug 8196] New: inheriting enveloping namespace prefixes is dangerous

The problem is that the wsf:Expression element is constructed in one context ("bare" as it were"), then it is later placed inside a SOAP envelope to which an arbitrary number of headers (along with their namespaces) may be added. At the time the client constructs the wsf:Expression it doesn't have access to the full list of in-scope namespaces that will exist once the request hits the wire because the message doesn't yet exist.

- gp


On 11/4/2009 5:01 PM, Asir Vedamuthu wrote:

This may lead to unpredictable behavior because,

in general, the person/software that composed the

wsf:Expression cannot know, a priori, what namespace

declarations will be in scope





We do not understand the basis for this danger. Any consumer can query the [in-scope namespaces] property [1] of an element information item and retrieve in-scope namespaces! XML Schema, XML Query and XSLT W3C Recommendations use the property successfully without introducing any prefix mapping.



[1] http://www.w3.org/TR/xml-infoset/#infoitem.element



Regards,



Asir S Vedamuthu

Microsoft Corporation



-----Original Message-----

From: public-ws-resource-access-notifications-request@w3.org<mailto:public-ws-resource-access-notifications-request@w3.org> [mailto:public-ws-resource-access-notifications-request@w3.org] On Behalf Of bugzilla@wiggum.w3.org<mailto:bugzilla@wiggum.w3.org>

Sent: Wednesday, November 04, 2009 4:19 PM

To: public-ws-resource-access-notifications@w3.org<mailto:public-ws-resource-access-notifications@w3.org>

Subject: [Bug 8196] New: inheriting enveloping namespace prefixes is dangerous



http://www.w3.org/Bugs/Public/show_bug.cgi?id=8196



           Summary: inheriting enveloping namespace prefixes is dangerous

           Product: WS-Resource Access

           Version: PR

          Platform: All

        OS/Version: All

            Status: NEW

          Severity: normal

          Priority: P2

         Component: Fragment

        AssignedTo: public-ws-resource-access-notifications@w3.org<mailto:public-ws-resource-access-notifications@w3.org>

        ReportedBy: gilbert.pilz@oracle.com<mailto:gilbert.pilz@oracle.com>

         QAContact: public-ws-resource-access-notifications@w3.org<mailto:public-ws-resource-access-notifications@w3.org>





In Section 6, "XPath Level 1 Expression Language", of WS-Fragment it states

that "The namespace bindings are evaluated against any namespace declarations

that are in scope where the XPath appears within the SOAP message." This may

lead to unpredictable behavior because, in general, the person/software that

composed the wsf:Expression cannot know, a priori, what namespace declarations

will be in scope (i.e. they don't know what the complete SOAP envelope will

look like).



Strawman Proposal: Use something like the <prefixMapping> element from CMDBf

[1]



[1] http://www.dmtf.org/standards/published_documents/DSP0252_1.0.0.pdf