Issue 250 - Proposal for Vote

[Rania Khalaf <rkhalaf@watson.ibm.com>]

Updated proposal based on discussions with the others.

SIDE NOTE 1: there is still a problem regarding start activity, which 
has its own separate open issue. This handles part but not all of that. 
We'll talk about that in the other issue's thread.


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CURRENT TEXT ON EXTENSION ACTIVITY IN SECTION 10:

If the element contained within the extensionActivity element is not
recognized by the BPEL processor and is not subject to a
mustUnderstand="yes" requirement from an extension declaration then
the unknown activity MUST be treated as if it were an empty
activity. In all cases however any standard-attributes or
standard-elements used on the contained activity MUST be treated as
defined by this specification.

REPLACE WITH:

If the element contained within the extensionActivity element is not 
recognized by the BPEL processor and is not subject to a 
mustUnderstand="yes" requirement from an extension declaration then the 
unknown activity MUST be treated as if it were an <empty> activity that 
has the standard-attributes and standard-elements of the unrecognized 
element: All its other attributes and child-elements are ignored. The 
standard-attributes or standard-elements MUST be treated as defined by 
this specification, whether the extension is understood or not.

Static analysis is performed by a WS-BPEL processor *after* it ignores 
the  non-standard-attributes and non-standard-elements  of an 
unrecognized extension activity not subject to mustUnderstand="yes. It 
may (lower-case) detect violations of some WS-BPEL required semantics. 
For example:

     * At least one start activity MUST be present - if an 
extensionActivity has a nested start activity, then a requirement could 
be broken if non-standard child constructs of the extensionActivity are 
ignored.
     * links MUST have exactly one source and target. if an 
extensionActivity has a nested activity that is the source or target of 
a link that crosses the extensionActivity boundary, then a requirement 
would be broken if non-standard child constructs of the 
extensionActivity are ignored.

If an extension activity allows a nested activity, its corresponding 
extension declaration SHOULD be subject to mustUnderstand="yes".