some of our concerns with the eventing proposal

[Scott Vorthmann <scottv@tibco.com>]

To inform the technical discussion we'll be having tomorrow, I'd like  
to shed some light on TIBCO's concerns with the existing proposal.   
The following is not exhaustive or terribly detailed, but is enough to  
begin discussion.

1. Eventing and publish-subscribe messaging are not the same thing.   
While it is useful for SCA to define a pub-sub alternative for the  
current wiring paradigm, that does not have to imply definition of new  
componentType concepts like consumer and producer.  We believe that  
pub/sub messaging can and should be fit into SCA without affecting the  
developer model.

2. SCA already provides a means to to define interface descriptions  
for one-way MEPs.  For example, abstract WSDL be used to define  
interface contracts for one-way interfaces; that is, interfaces  
containing exclusively in-only or out-only MEPs.  Forcing developers  
to use or define alternate descriptions for the set of inbound  
messages, or completely forgoing those definitions, forces developers  
to a different model for no apparent benefit.

3. The proposed event definition language is entirely new ground from  
a standardization perspective. Standards should follow state-of-the- 
art, not lead it.  In any case, the proposal should be cast as an  
alternative interface type appropriate to services and references.

Scott