New Issue - <toPart>s and Anonymous WSDL Variables Clarification (PR2)

["Monica J. Martin" <Monica.Martin@Sun.COM>]

Title: <toPart>s and Anonymous WSDL variables clarification (PR2)
Target: WS-BPEL v2.0 Specification PR2 Draft
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.

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
  1. Effect changes above as stated - Add one new static analysis 
requirement and correct SA00050.
  2. 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.

References:
Current draft for PR2:  
http://www.oasis-open.org/committees/download.php/21575/wsbpel-specification_public_review_draft_2_diff.pdf 
Public Review

schema changes for PR2:
http://www.oasis-open.org/committees/download.php/21724/xsd%20changes%20for%20second%20public%20review.zip 


15 day announcement:
http://lists.oasis-open.org/archives/wsbpel/200701/msg00004.html