- From: Jon Dart <jdart@tibco.com>
- Date: Wed, 25 Jun 2003 09:56:15 -0700
- To: "Burdett David" <david.burdett@commerceone.com>
- CC: "'public-ws-chor@w3.org '" <public-ws-chor@w3.org>
Burdett, David wrote: > Also in my spec I assumed that an Interaction was implmented by a single > message (ignoring signals) sent from one role to another. In your example > for "DoLogin" to succeed, you would need two messages the LoginRequest from > the client to the server and the LoginResponse from the server to the > client. The result could be either succeed or fail. One issue here for me is how this maps into the SOAP/WSDL layer (if there is one). The simple way to implement login is with a request/reply MEP. Then there are two messages, as you suggest, but it is one operation, in the WSDL sense of the term. Maybe it should be possible to include such a MEP in the choreography without explicitly showing the two messages - it is a logical unit. Generally, I am concerned about duplicating WSDL layer information into the choreography layer. When you have duplication you also have the possibility for the information to get out of sync. Also re failure: if you are using SOAP, the WSDL tells you if a fault condition is possible. If this fault leads to a state transition it may need to be handled explicitly in the choreography. But perhaps there should be a default behavior (termination of the choreography?). Also something like the BPEL concept of fault handlers may be necessary. There is no equivalent concept in BurdettML, AFAIK. --Jon
Received on Wednesday, 25 June 2003 12:56:23 UTC