I am trying to understand how a contribution that contains a mix of artifacts, including JEE artifacts, should be handled by Tuscany and the runtime into which it is being deployed.
Here's a scenario just to make it concrete. Imagine I have a contribution that includes some JEE UI components like some servlets or JSPs, some Java SCA components, and just to make it tricky an EJB that is also an SCA component (if that's not possible yet then I am guessing it will be in the future). And suppose, to be specific, that I want to deploy this onto Websphere Application Server (WAS). In this scenario I really want to understand things like what should happen during deployment and runtime, and how Tuscany and WAS should cooperate during class loading and instantiation and do any dependency injection. I can think of two different approaches. The first is to put Tuscany firmly in charge, which as far as I can see is roughly what the SOA feature pack for WAS does: you define Business Level Applications (which must be related to domains in some way) and then you can add contributions to them explicitly and start and stop them explictly from extra panels in the admin console. I imagine (only imagine, note, I haven't looked) that when you add the contribution it gets put somewhere; when you start the BLA a domain gets created, and the SOA FP is in charge while classes get loaded and instantiated and dependency injection gets done. But, I don't know what would happen with a contribution with an ejb in it since the SOA FP doesn't handle JEE artifacts yet. At what point would the ejb get given to the ejb container? The other approach is to leave WAS in charge as far as possible. Normal WAS deployment time behaviour is to examine the ear file and to pass whatever it finds to the appropriate handler for deployment: servlets to the web containre, ejbs to the ejb container etc. I can imagine just adding in a new step which is "during normal ear file processing, if you find an SCA contribution, locate an SCA domain and give the contribution to it". In fact with WAS 6.1 which is based on OSGI you can add in processing like this non-invasively. But then in this case if Tuscany opened the contribution and found an ejb that was a component would it have to give the ejb back to WAS? That's just thinking about deployment. I have various things that are puzzling me about what should happen at runtime: who should create, start and stop the SCA domain, who actually does class loading, Tuscany or WAS, and if WAS loads a class and instantiates it and it is a component then how does it give the instance to Tuscany for dependency injection. Essentially it seems to me that Tuscany and WAS are both meaty runtimes that are used to being in charge by themselves, especially WRT class loading and instantiation. Has anyone thought this all through and can tell me how it ought to work? Matthew Peters Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU
