Issue - R48 - <toPart>s and Anonymous WSDL Variables Clarification

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Issue - R48 - <toPart>s and Anonymous WSDL Variables Clarification 
Status: received

Date added: 23 Jan 2007

Date submitted: 22 Jan 2007

Submitter: Monica J. Martin

Document: WS-BPEL 2.0 second public review text

Description: In Section 10.3.1, the use of <toPart> and <fromPart> is described. However, conflicting information exists in <toPart> copy mechanics given the normative requirement included in SA00050. This may be a cut-paste error during construction of this section. In addition, it is inferred that only one <toPart> should exist for each part in the WSDL message definition and this should be explicit.  Both these should be addressed in the Public Review2 to ensure proper use of these capabilities.

Submitter's proposal: 

Section 10.3.1, Change from:

The <toPart> elements, as a group, act as the single virtual <assign>, with each <toPart> acting as a <copy>....[existing static analysis requirement SA00050] When <toParts> is present in an <invoke>, it is not required to have a <toPart> for every part in the WSDL message definition, nor is the order in which parts are specified relevant. Parts not explicitly represented by <toPart> elements would result in uninitialized parts in the target anonymous WSDL variable used by the <invoke> or <reply> activity.  Such processes with missing <toPart> elements MUST be rejected during static analysis.

Change to: 

...The <toPart> elements, as a group, act as the single virtual <assign>, with each <toPart> acting as a <copy>. [add sentence] [add Static Analysis Requirement] At most one <toPart> exists for each part in the WSDL message definition. If a process includes more than one <toPart> for each part in the WSDL message definition, that process MUST be rejected by static analysis.[end sentence]...

[updated static analysis requirement SA00050] When <toParts> is present, it is required to have a <toPart> for every part in the WSDL message definition; the order in which parts are specified is irrelevant. Parts not explicitly represented by <toPart> elements would result in uninitialized parts in the target anonymous WSDL variable used by the <invoke> or <reply> activity. Such processes with missing <toPart> elements MUST be rejected during static analysis.

Appendix B

Effect changes above as stated - Add one new static analysis requirement and correct SA00050.

Renumber static analysis requirements or consider adding the new
static analysis requirement at the end of the list to minimize changes required.

Notes:

This issue doesn't specifically reference the known but rare case
when there could be multiple toPart from the same BPEL variable.
An example would be if the process always assumes the ship-to and
billing addresses are the same, the same address variable could be
copied to both the ship-to and billing address parts of the
anonymous PO message.

Renumbering of static analysis requirements may be laborious;
perhaps another option could be used to enable their effective use
in the specification and by users.

See topart-issue-pr2.zip  (document details) for a redlined copy of changes proposed for Section 10.3.1.

Links: Monica J. Martin, 22 Jan 2007     
, 22 Jan 2007     
Monica J. Martin, 22 Jan 2007     
Alex Yiu, 23 Jan 2007

Changes: 23 Jan 2007 - new issue

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