Development Environment

Building single modules

When working on a single Opencast module, it can be extremely helpful to watch the newly built version and include it automatically in the Opencast OSGi infrastructure. This can be done through the bundle:watch command in Karaf. The workflow would be as follows:

  • Start Opencast and use la -u in the Karaf console to list all installed bundles/modules. Note down the IDs of the bundles you want to watch.
  • Use bundle:watch IDs to watch the desired modules, e.g. bundle:watch 190 199
  • Make your changes and rebuild the module (e.g. execute mvn clean install in the module folder).
  • Watch how Karaf automatically redeploys the changed jars from your local Maven repository. You can verify that everything went smoothly by checking the log with log:tail.

The updated bundles are only available in the currently running Karaf instance. To create a Opencast version that has this changes permanently, you have to run mvn clean install in the the assemblies directory again. Your current instance will be deleted by the new assembly!

In several cases the bundle:watch can bring Karaf in an unstable condition, as dependencies between bundles will not correctly be restored, after the new bundle has been deployed.

Attaching a Remote Debugger to Karaf

To debug a running Opencast system, you can attach a remote debugger in your IDE (Eclipse or NetBeans, i.e.). For that you have to enable the remote debugging in Karaf OSGI server that runs Opencast.

You have to add "debug" as an additional paramenter to the Opencast start script:

bin/start-opencast debug

If you want to enable debug permanently you can export the variable in the shell:

export DEFAULT_JAVA_DEBUG_OPTS='-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005'

You can connect the remote debugger of your IDE on port 5005.

For more information on remote debugging with Karaf you can visit this site.

It is not recommended to enable remote debugging on production systems!