- From: Martin Chapman <martin.chapman@oracle.com>
- Date: Mon, 7 Jul 2003 09:04:52 -0700
- To: "Champion, Mike" <Mike.Champion@SoftwareAG-USA.com>, <public-ws-chor@w3.org>
I think Mike has made a good point here. If a composition presents a new wsdl, it has to be hosted somewhere, even if its job is just to delegate out to the parties (Yaron made a similar point the other week). I thought we had ruled out this sort of central controller, for autonomous peer-peer environments. Thinking about this a little more, the only way I can see nesting of choreographies is for one choreography to take on the role(s) defined in another choreography. Something like: Choreo 1: pay role payer role payee role cardagency payer sends payment details to cardagency //cardagency verifies and does stuff cardagency deposits money from payers card cardagency credits money (minus fee) to payees account Choreo 2: Purchase goods role buyer role seller reuses Choreo 1: buyer=payer, seller=payee buyer submits PO seller checks warehouse seller send invoice to buyer buyer submits payment details (kicks off choreo 1) blah, blah Something like that anyway. Martin. > -----Original Message----- > From: public-ws-chor-request@w3.org > [mailto:public-ws-chor-request@w3.org]On Behalf Of Champion, Mike > Sent: Monday, July 07, 2003 7:20 AM > To: public-ws-chor@w3.org > Subject: RE: Revised: Mission Statement > > > > > > > -----Original Message----- > > From: Monica J. Martin [mailto:monica.martin@sun.com] > > Sent: Monday, July 07, 2003 10:02 AM > > To: Jim Hendler > > Cc: Steve Ross-Talbot; Nickolas Kavantzas; Cummins, Fred A; Martin > > Chapman; Yaron Y. Goland; public-ws-chor@w3.org > > Subject: Re: Revised: Mission Statement > > > > > mm1: Then could we revise this working definition? > > > > > **A service composition is a composition of services that > > results in a > > > ANOTHER service. THIS service can be the combination of > > distinct parts > > > to form a whole of the same generic type. The web services could be > > > combined to achieve a specific goal.* > > I appreciate the power of recursion as much as anyone <grin> but > defining a > service composition as a composition of services is not likely to win us > great praise for our grasp of the subtlties here. Could we say "is a > [concatenation | embedding | nesting | combination | whatever > combination ] > ..."? Or something other than "composition" anyway. Or is "composition" > well-defined somewhere else? > > Also, we need to keep the other parts of the mision statement in > mind here. > If, when when one is combining services to present a single WSDL interface > to the outside world and the global state of the interaction does not have > to be exposed, one is doing that O-word thing rather than "Choreography." > How can we distinguish Composition in the BPEL sense from > Composition in the > Choreography sense? > >
Received on Monday, 7 July 2003 12:04:53 UTC