Restlet improves OSGi support: new edition and update site

While OSGi has been for a long time an important deployment environment for Restlet developers, including an innovative project lead by NASA JPL, we have seen a surge of interest in the recent years.

The rise of REST, the addition of an Eclipse Public License option to Restlet and an increased effort from Restlet community is starting to bring new fruits!

Edition for OSGi Environments

Since version 1.1, Restlet has always tried to be friendly to OSGi developers by ensuring that each Restlet module distributed as a JAR file was also a valid OSGi bundle, including correct manifest information.

We also ensured that dependent libraries were distributed as bundles as part of the various Restlet editions and distributions (Zip and Windows installer).

In practice, OSGi development isn’t supported on platforms such as Android, GAE and GWT, leaving the developer free to choose from either the Java SE or Java EE editions of Restlet, as both contain different extensions usable in OSGi such as the Servlet and Jetty extensions.

Progressively, we realized that a new edition of Restlet dedicated to OSGi environments such as Equinox and Felix was necessary to clarify the situation and make space for more OSGi specific features.

Using our automated Restlet Forge, we were able to deliver this new edition, including dedicated Javadocs and distributions as illustrated above.

Eclipse Update Site

In addition, we worked hard on providing a new distribution channel specific to this OSGi edition : an Eclipse Update Site supporting easy installation and automated update right from Eclipse.

Note that this is only recommended if you intended to develop OSGi applications leveraging Restlet, not applications for other target environments such as Java EE or GAE. In the later cases, you should either manually copy the JAR files in your Eclipse project or rely on our Maven repository using a tool such as m2eclipse.

In order to use the Eclipse update site, you should simply use this URL: http://p2.restlet.org/2.1/

More detailed instructions about using this update site are available on this page.

Restlet integration with ECF

In addition, thanks to the work of Scott Lewis, the Eclipse Communications Framework lead, an integration of Restlet with ECF is now available.

This integration supports the OSGi Remote Services specification by adding REST/HTTP bindings based on Restlet and leveraging the Restlet extension for OSGi introduced below.

For additional details, you can read his blog posts #1 and #2. Scott was also very helpful by providing regular feed-back on all others aspect of this blog post.

Upcoming Restlet extension

Finally, based on work initiated via a Google Summer of Code project in 2010, a Restlet extension for OSGi is entering in the Restlet Incubator with the goal to become part of the 2.2 version of the framework.

The extension facilitates the development of very dynamic Restlet applications, supporting for example the live addition of resources and virtual hosts.

This org.restlet.ext.osgi extension is lead by Bryan Hunt and has received significant contributions from Wolfgang Werner.

Conclusion

Step after step, Restlet support for OSGi and the Eclipse ecosystem is growing and we will continue to work in this direction, with plans to add visual tooling for Restlet in Eclipse and to provide more integration with OSGi standard services such as the log service. As always, stay tuned!