On Wed, 30 Jun 2004, Abbie Barbir wrote:
I agree with your orchestration example. The point here there are
other work that does that, check CDL in W3C and BPEl in OASIS.
My understanding is that CDL is a much higher-level _declaration_
language then an if-condition-then-action procedural P. CDL is also
not meant to be written by humans directly. Here is a cryptic CDL
example, FWIW:
<choreography name="PurchaseChoreo" root="true">
<variable name="purchaseOrderAtRetailer"
informationType="purchaseOrder" role="Retailer"/>
<choreography name="CustomerNotifyChoreo">
</choreography>
<workunit name="RetailerNotifyCustomer"
guard="cdl:getVariable(PoAckFromWareHouse, tns:WareHouse)">
perform choreographyName="CustomerNotifyChoreo"
</workunit>
</choreography> <!--end of root choreography -->
It is possible that P code (especially service configuration code) can
be generated based on CDL and other information, but other than that I
do not see a significant overlap between P and CDL. Do you?
I am even more fuzzy on BPEL. I looked at BPEL4WS specification. It
seems to be solving a similar problem we are solving here, but from
business interactions point of view. It is very business-specific so I
am not sure we can use anything as-is. However, we may be able to use
some nice ideas/approaches.
If there is an OPES participant who understands BPEL and related
languages, please speak up and prevent us from reinventing wheels when
possible!
Thank you,
Alex.