The Apache Tuscany team announced today the 1.1 release of the Java SCA project.
Apache Tuscany is a runtime environment based on the Service Component Architecture (SCA). SCA is a new component model that facilitates the construction of composite applications. SCA is a set of specifications initially developed by IBM and BEA which are now being standardized by OASIS as part of the Open Composite Services Architecture (Open CSA). The members of the working group include: BEA, IBM, Primeton, SAP, Sun Microsystems, Oracle, Red Hat, SOA Software, Xcalia...
The Open SOA organization defines SCA as a:
Service Component Architecture (SCA) provides a programming model for building applications and systems based on a Service Oriented Architecture. It is based on the idea that business function is provided as a series of services, which are assembled together to create solutions that serve a particular business need.
The Tuscany SCA Java 1.1 release adds a number of features including:
- a JMS binding,
- improved policy support
- an implementation extension for representing client side Javascript applications as SCA components.
InfoQ: What type of feedback did you receive after the 1.0 release?
JS: We received good feedback from our users, with more users posting to our user list with 1.0. Overall I think they found Tuscany easy to install and use while providing good support for the SCA 1.0 spec.
We also got some requests for:
- more policy support
- security policies, which we have improved in 1.1
- transaction policies, we're working on it
- JMS (now available in 1.1)
InfoQ: What kinds of project people are currently starting with Tuscany?
JS: They are literally across the board, from students using it to experiment with grid and distributed computing to real world banking applications.
InfoQ: Where do you see the sweet spots of adoption of an SCA infrastructure?
JS: Web Service based applications which can rely on a simpler programming model and composition. There is also more traditional integration, again, with a simpler and consistent programming model across bindings and component implementation types.
What's new is that we are starting to see SCA helping people build Web 2.0 applications as well.
InfoQ: on that note, could you explain how the the "widget" implementation works ?
JS: With an
Basically it is about embracing Web 2.0 client components in a distributed SCA composition.
This how you declare references using JavaScript:
//@Reference
var catalog = new Reference("Catalog");
//@Reference
var shoppingCart = new Reference("ShoppingCart");
We generate some additional JavaScript after introspection of the references the implements all the the plumbing code to
support JSON-RPC and ATOM and the Reference class wrapping the references that you can use in your business logic.
<script type="text/javascript" src="store.js"></script>
Some of the demo code can be found here.
InfoQ: What about the support for BPEL?
Luciano: It's not complete yet. Services are supported, but references are not. I am currently involved in completing that effort. Properties are not supported either, but they will require an extension to the BPEL language. This may come next if it is requested by the community. I have just updated the BPEL implementation guide.
InfoQ: What's coming ahead ?
JS: The Tuscany community will have to decide (as we're just getting 1.1 out) but I envision progress in the following areas:
- simpler and more complete SCA policy support
- more policies (making progress with the transaction policy)
- improved end-to-end SCA contribution / deployment / distribution story
- an SCA domain administration application
- integration with Geronimo (there's a prototype in the Geronimo sandbox)
- improvements of the Web 2.0 bindings (maybe using Apache Abdera for ATOM and adding cross-domain support to the JSONRPC binding)
- optimizations of the Tuscany databinding support
- more platform integration testing (Tomcat, Geronimo etc.)
InfoQ: How does IBM markets Apache Tuscany in the WebSphere brand?
JS: More information can be found here, but basically IBM's WebSphere Application Server v6.1 SOA feature pack leverages Apache Tuscany to provide an implementation of SCA.
Thank you !