Editing team issue - EventHandler und Concurrency?

[Francisco Curbera <curbera@us.ibm.com>]

Dieter raised the following problem with the text of Section 13.5.7:

*--

It seems that there are conflicting statements in WS-BPEL spec section
13.5.7. "Concurrency Considerations" (for event handlers).

Consider an event handler with a request-response operation. The
"constraint that there can be at most one outstanding synchronous request
on a given partner link at a given port type and operation" implies that a
second request has to be rejected with a standard fault
"conflictingRequest" as long as a first request is being processed.

This does not fit to the other statement "individual onEvent event handlers
are permitted to have several simultaneously active instances".

*--

After a short mail discussion between Dieter, Satish and myself we agreed
that this looked like a text clarification more than a real issue, and that
it would be better for the editor's team to handle is. The proposed change
would affect the second paragraph in Section 13.5.7 would be as shown
below. If nobody objects (please speak up!) I would like to have this
directly handled by the editor's team.

-> Change from:

Note that, unlike onAlarm event handlers, individual onEvent event handlers
are permitted to have several simultaneously active instances.  A private
copy of all process data and control behavior defined within an event
handler is provided to each instance of an event handler.  This includes
the behavior of links defined within an event handler.  Each instance of
the event handler must independently evaluate the status of the link as
needed.

-> To:

Note that, unlike onAlarm event handlers, individual onEvent event handlers
are permitted to have several simultaneously active instances. The presence
of multiple simultaneous active instances of the same event handler is not
considered to violate the constraint regarding outstanding synchronous
requests stated before, because each instance of the event handler is
executed within its own private environment. A private copy of all process
data and control behavior defined within an event handler is provided to
each instance of an event handler.  This includes all variables,
correlation sets and partnerLinks declared in scopes local to an event
handler as well as the behavior of links defined and used within an event
handler.  Each instance of the event handler must independently evaluate
the status of links local to the handler as needed.  Note that links are
not permitted to cross an event handler boundary (see Section 12.5).