A Day At The Races

The Grails OSGi plugin provides scripts to package a Grails application as an OSGi bundle. Additionally the bundle(s) may be run in an OSGi container assembled ad hoc by the excellent Pax Runner or deployed to a SpringSource DM Server.

License

The OSGi plugin is released under the Apache License 2.0.

Installation

Simply call grails install-plugin osgi to install the OSGi plugin.

Usage:

Creating an OSGi bundle from the Grails application

grails bundle
grails prod bundle

Running the bundle

grails run-bundle
grails prod run-bundle

The application can be accessed at http://localhost:8080/myapp/.

Note: at first start the OSGi runtime is assembled, which may take some time, while Maven is downloading the internet…

Creating a zipped OSGi runtime

grails assemble-osgi-runtime
grails prod assemble-osgi-runtime

Deploy bundle to DM Server

grails dmserver deploy (Not yet implemented)

Getting around the OSGi runtime

The OSGi runtime is based on the Equinox OSGi framework, Pax Web and some additional bundles.

Web Console

The Felix Web Management Console provides excellent insight into the inner workings (see Screenshots). It can be accessed at http://localhost:8080/system/console/ with user “admin” and password “admin”.

Shell Console

The command grails run-bundle drops the user in the Equinox Shell. Typing help shows the available commands.

How it works

In order to be a valid OSGi bundle, the application is war’ed and provided with the necessary bundle manifest headers (see scripts/_Event.groovy for details).
The bundle can be created using grails bundle.

The OSGi runtime is assembled in the target/osgi directory.

Source code and Issues

The source code is hosted at GitHub, issues can be reported here.

Roadmap

• make bundle generation configurable (e.g. include/exclude dependencies, …)
• make OSGi runtime created by grails run-bundle and grails assemble-osgi-runtime configurable
• support auto-reloading of changed artifacts
• use Spring DM instead of Pax Web as Web extender
• remove dependencies from bundle and package them as their own plugins (re-using existing bundles from the SpringSource Enterprise Repository
• export main Grails beans and application context as OSGi service
• export services as OSGi service (via static expose = 'osgi')
• provide access to OSGi BundleContext to artifacts (controllers, services, …)
• implement deployment to DM Server
• consider other deployment options: Apache Karaf, …

I’m terribly sorry, but I have to (at least temporarily) pull the plug on Monitor Plugin due to possible conflicts with my employer.

In my professional live I’m working on high availability and monitoring software. When I showed the plugin to my employer,
he asked me to suspend any activities regarding the plugin, until they decide whether this conflicts with our products.

I hope I will be able to continue with the monitor plugin, but until this issue is resolved, I have removed both sources and
downloads.

Regards,

Wolfgang

Just in time for the upcoming 2008 Groovy/Grails Experience, I released my Grails Monitor plugin in version 0.1 (Apache License).

It’s basically a preview version, but for anybody who was dying to get his or her hands on it, the Grails wiki has all the details on how to install and use the Monitor plugin. For an introduction, see my previous post.

Installation is still a little clumsy as you have to jump through a few hoops because some patches to Grails and the Quartz plugin are needed in order to get the monitor plugin installed and running.

Lots of features are still missing, but for a first version it’s not too bad. I’m open to suggestions, criticism and usability reports. Of course, patches are most welcome

Happy monitoring,

Wolfgang