On Dec 13, 2007 3:45 PM, Peng Han <[EMAIL PROTECTED]> wrote: > Hello All: > > > > I am a newbie for Tuscany. After reading the architecture guide, I still > didn't quite understand how the Tuscany > > based SCA applications actually run. I mean, if we are using a top-down > approach and build everything from > > scratch, it will be more easy to understand. However, I don't know whether > Tuscany can support the Bottom-Up > > approach and enable users to reuse some existing sources and platforms. > For > example, I have some BPEL processes > > running on an ActiveBPEL server instead of ODE. Is it Possible for me to > include them as components in a SCA > > composite in Tuscany. And if so, how does Tuscany handle different > component > runtime and make appropriate > > selections? > > > > Thanks. > > > > Best Regards > > > > Peng Han > > FernUniversitaet in Hagen > > Welcome Peng.
SCA (and Tuscany) tries hard not to force you into a big bang situation where you have to build everything from scratch, the top-down approach that you describe. Taking the example of a BPEL process that already exists there are a number of ways that you could reuse it or integrate with it, for example. - deploy the BPEL process as a component within the Tuscany runtime. Tuscany SCA has an extension "implementation.bpel" that allows SCA components to be implemented using BPEL scripts. Our support for BPEL in Tuscany uses the ODE engine under the covers. So, in theory, you could take an existing BPEL script and create an SCA component using the script as the implementation. You would describe the services and references that the component provides and requires. Then you would wire to and from the component as you would with any other SCA component. - With the BPEL script running in it's current ODE container you could, in theory, have SCA components call the script through the SCA web service binding without including the BPEL script as an SCA component. - With the BPEL script running in it's current ODE container you could, in theory, have it call SCA components through their SCA web service binding without including the BPEL script as an SCA component. I have said "in theory" a few time here as I haven't actually tried these options but they are certainly in keeping with the way Tuscany SCA is intended to work. Regards Simon
