RE: [wsbpel-spec-edit] Optional and required nature of @variable issue

["Satish Thatte" <satisht@microsoft.com>]

makes sense to me

 

 

 

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From: Prasad Yendluri [mailto:pyendluri@webmethods.com]
Sent: Wednesday, October 27, 2004 5:07 PM
To: wsbpel-spec-edit@lists.oasis-open.org
Subject: [wsbpel-spec-edit] Optional and required nature of @variable issue

Folks,

Per the action I took on the BPEL call this morning, I am proposing the following issue text. Want to run it by you for a sanity check. Can you pls let me know if this matches your understanding or if needs any amendments..

Thanks.

The optional or required nature of Variable attribute is inconsistent in the specification. On <receive> activity, onMessage clause of the <Pick> activity the @variable is optional.  Where as on <onEvent> handler the @variable is required.  Additionally per section 15.1 it is permissible in abstract processes to omit the variable reference attributes from the <invoke/>, <receive/>, and <reply/> activities. However for executable processes there is no specification on the optional or required nature of @variable. In the case of OnEvent handler which can have several simultaneous active instances, the @variable is defined to be of @messageType declared within an implicit scope associated with the event handler; upon receipt of the input message the event handler is required to assign the input message to the variable before proceeding to perform the event handler activity, which makes the @variable required.  This inconsistency of  optional and required nature of the @variable on different activities seems to be a source of confusion, that needs to be clarified in the specification.
Proposed Resolution: Consistently require the @variable on all these activities for executable processes making it optional for abstract processes only.