On Fri, May 15, 2009 at 11:38 AM, Florian Fernandez <[email protected]> wrote: > Dear Ant (and other Tuscany users): > > First of all, thank you very much for your ample explication of the existing > possibilities. > Please, let me put my remarks and/or further questions within your response > text: > >> Tuscany and SCA _DOES_ also apply to the presentation layer and >> provides various means of "SOAfication". >> >> There is a specification that defines how SCA can be used in a JEE web >> container. [...] >> >> There are two main approaches: >> >> 1) Have the web application presentation layer outside of the SCA >> domain and access the domain as a remote client calling domain >> services >> 2) Have the web application part of the SCA domain and use SCA >> assembly to connect the presentation layer to data access and biz >> logic services >> >> The main advantage of (2) is that it enables using the all the >> capabilities of SCA such as injection, declarative assembly, easy >> re-wiring etc. > > It's precisely approach (2) I'm pretending to achieve. > >> The main difference to the presentation layer code between using the >> two approaches is with how it gets hold of the services to use. Using >> approach (1) the presentation layer code needs to either: >> >> (1a) hardcode the protocol and endpoint of the service and invoke it >> using its own support for that protocol. For example if ZK natively >> supports JSON-RPC it could use that to invoke Tuscany/SCA services >> exposed with <binding.jsonrpc> >> >> (1b) if the ZK application is running locally to the SCA domain it can >> get hold of the Tuscany SCADomain or Node object and use the >> getService method to get an invocable proxy for the SCA services > > If I would follow the more disadvantageous (static) approach (1), then > solution (1b) would hold in my case. But I'd prefer the more dynamic and > SCA-incorporated approach (2) over this more static one. > >> Using approach (2) the presentation layer code needs to either: >> >> (2a) if the presentation layer code uses a web technology that has SCA >> integration then it simply uses SCA annotations in the presentation >> layer code and the Tuscany runtime will inject the required objects > > Yes, this is the 1st possibility I'm aware of, using the SCA-supported > JSF/JSP technology with or without the Dojo Toolkit -- I'm looking for an > *ajax-ified* web presentation solution; Thus, this could be an equivalent > alternative to my mentioned ZK-based scenario. > I took ZK into a closer consideration because I'm already more confortable > with ZK as with Dojo, and IMHO it has a "nicer look" and a more abundant set > of ui components to choose from (at least at the time I did my last research > on these issues). > >> (2b) if the presentation layer code web technology being used does not >> support native SCA integration then it needs to get hold of the SCA >> ComponentContext and manually look up the required objects > > Unfortunately this is the case for ZK (see further below for a related > question, please). > >> The main advantage of (2b) over (1b) is that it still provides support >> for the capabilities of SCA such as declaritive assembly, easy >> re-wiring etc. >> >> Option (2a) provides the cleanest approach but it requires specific >> Tuscany support the web toolkit being used. Tuscany provides this >> integration code for some common web technologies and toolkits like >> Servlets, JSP, JSF, Stripes, (and soon Wicket), and Tuscany's >> proprietary <implementation.widget>. Tuscany doesn't have any support >> for ZK, it would be fairly easy to write that support but we can't do >> it here at Apache Tuscany as the ZK license is GPL which is a problem >> license so Apache code can't use it directly. We could provide help if >> you are interested in writing SCA support in ZK, but we couldn't host >> that code within the Tuscany project itself. > > For the case I would insist on ZK and therefore be obligated to write some > Tuscany "enhancements": > Can anyone of you provide -- or point me to -- the following information: > > 1. Which programmatic Tuscany resources (Tuscany components) would be > involved? >
For your ZK webapp you need: - update the webapp WEB-INF\web.xml to include the TuscanyContextListener, see [1] - a web.composite file in the webapp WEB-INF\ folder, see [2] - any other classes/resources associated with the components defined in that web.composite, eg [3] - add SCA annotations to the ZK resources to get the SCA references/properties/etc injected. See the @Reference in [4] for an example in a Stripes component. Then it gets a bit hazy as it depends on the capabilities of ZK and I don't know anything about ZK. Looking at the ZK tutorial at http://www.zkoss.org/doc/tutorial.dsp i guess the idea would be to do those above steps with the @Reference going in the ResortController class. Then you need to work out where in ZK it instantiates the ResortController class and see how to hook in there to do annotation injection. Googling on ZK it sounds like it should be possible to do this hook. > 2. What exactly would be the way to go? Trying to implement 2a for ZK would be interesting > > 3. Which analogous & existing "technology incorporation" could I look at, to > have a working example to study from? > (An enlisting of the relavant source code resources would be sufficient) > The Tuscany sample using the Stripes Web Framework is an example see: https://svn.apache.org/repos/asf/tuscany/java/sca/samples/webapps/helloworld-stripes/ and the Tuscany integration module for that: https://svn.apache.org/repos/asf/tuscany/java/sca/modules/stripes/ > And last but not least a still open question: > 4. Does anyone of you tried out the alleged ZK integration into Spring as > WebFlow app and running within a plain SCA scenario? > Is it really possible? And, could you please share your experiences with > this approach? > That sounds like another approach that could be interesting though i don't know anyone who's tried it. Tuscany has Spring integration so it may be possible to use the existing ZK/Spring integration and then use SCA annotations in the Spring beans to have them use SCA/Tuscany. That approach would also help with Blaze integration thats come up on another thread by using the Spring-Blaze integration. > > So, that's all for now. > > Thanks a million for all your constructive hints in advance. > > Best regards, > Florian > [1] https://svn.apache.org/repos/asf/tuscany/java/sca/samples/webapps/helloworld-stripes/src/main/webapp/WEB-INF/web.xml [2] https://svn.apache.org/repos/asf/tuscany/java/sca/samples/webapps/helloworld-stripes/src/main/webapp/WEB-INF/web.composite [3] https://svn.apache.org/repos/asf/tuscany/java/sca/samples/webapps/helloworld-stripes/src/main/java/sample/ [4] https://svn.apache.org/repos/asf/tuscany/java/sca/samples/webapps/helloworld-stripes/src/main/java/mystripes/action/HomeActionBean.java
