How To Create A New Plugin

Plugin Archetype

The Maven Archetype Plugin provides a convenient mechanism for automatically generating projects. Project templates are called Archetypes and they are basically maven artifacts of a special kind of packaging, ‘maven-archetype’.

With the Theodul Plugin Archetype you can create a new plugin project in no time and start writing the plugin’s business logic right away, without caring about the POM or SCR component declarations.


The Theodul Plugin Archetype is included in the Opencast source code (Theodul Player branch) in the modules directory. To make the artifact available on your system you need to install it like any other atrifacts. In the Opencast source directory type:

> cd modules/matterhorn-engage-theodul-plugin-archetype
> mvn install

After successful build and installation the archetype is available in your system.

Generating a new plugin

To generate a new plugin project simply go to the modules directory inside the Opencast source directory and type:

> mvn archetype:generate -DarchetypeGroupId=org.opencastproject -DarchetypeArtifactId=matterhorn-theodul-plugin

Provided the archetype is installed maven will now ask you for the properties configuration for the new project:

[INFO] Generating project in Interactive mode
[INFO] Archetype [org.opencastproject:matterhorn-theodul-plugin:1.5-SNAPSHOT] found in catalog local
Define value for property 'groupId': : org.opencastproject
Define value for property 'artifactId': : matterhorn-engage-theodul-plugin-test
Define value for property 'version': 1.0-SNAPSHOT: : 1.5-SNAPSHOT
Define value for property 'package': org.opencastproject: : org.opencastproject.engage.theodul.plugin.custom.test
Define value for property 'plugin_description': : A test plugin
Define value for property 'plugin_name': : testName 
Define value for property 'plugin_type': : custom
Define value for property 'plugin_version': : 0.1
Define value for property 'plugin_rest': : false
Confirm properties configuration:
groupId: org.opencastproject
artifactId: matterhorn-engage-theodul-plugin-test
version: 1.5-SNAPSHOT
package: org.opencastproject.engage.theodul.plugin.test
plugin_description: A test plugin
plugin_name: test
plugin_rest: true
 Y: : y
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: matterhorn-theodul-plugin:1.5-SNAPSHOT
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: org.opencastproject
[INFO] Parameter: artifactId, Value: matterhorn-engage-theodul-plugin-test
[INFO] Parameter: version, Value: 1.5-SNAPSHOT
[INFO] Parameter: package, Value: org.opencastproject.engage.theodul.plugin.test
[INFO] Parameter: packageInPathFormat, Value: org/opencastproject/engage/theodul/plugin/test
[INFO] Parameter: package, Value: org.opencastproject.engage.theodul.plugin.test
[INFO] Parameter: version, Value: 1.5-SNAPSHOT
[INFO] Parameter: plugin_description, Value: A test plugin
[INFO] Parameter: plugin_name, Value: test
[INFO] Parameter: groupId, Value: org.opencastproject
[INFO] Parameter: plugin_rest, Value: true
[INFO] Parameter: artifactId, Value: matterhorn-engage-theodul-plugin-test
[INFO] project created from Archetype in dir: /home/wulff/code/UOS/plugin-archetype/test/matterhorn-engage-theodul-plugin-test
[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3:39.195s
[INFO] Finished at: Thu Jan 23 15:48:37 CET 2014
[INFO] Final Memory: 15M/308M
[INFO] ------------------------------------------------------------------------

There you go, the newly created plugin project is waiting to be filled with life in the directory that is named after the atrifactId you entered before.

Project Properties

In addition to the above explanation, here is a description of the properties you have to specify when generating a new project with the Theodul Plugin Archetype:


Maven group ID. For the Opencast developers this is



Maven artifact ID. Name by which your project is identified as an artifact by maven. Think of it as the project name. It will also be used as the name for your projects root directory. During the course of the Theodul project the following naming scheme came up:

matterhorn-engage-theodul-plugin-<plugin type>-<plugin name>


The project version. For Opencast developers: simply put in the version of the Opencast source tree your are working on.


The Java package in which the source for the back end part of your plugin will live. The following scheme is used by the Theodul developers:

org.opencastproject.engage.theodul.plugin.<plugin type>.<plugin name>


The version of the plugin itself. This is not to be confused with the maven project version which will, for instance, be updated when the Opencast version changes.


The type of the plugin to be created. See Possible types are: custom, controls, timeline, video, description, tab


The name by which your plugin will be registered by the plugin manager when running.


(optional) A short description of the plugin. The description will be provided by the plugin list endpoint together with the other plugin data.


(boolean) Whether or not the plugin should provide a Opencast Rest endpoint. If set to true, the Java class that makes up the back end part of your plugin will be augmented with the annotations necessary to work as a Rest endpoint provider in Opencast. Also an example endpoint (GET:sayHello) will be generated.

Example Plugin

Have a look at the snow showcase example plugin (custom).


To display debug information in the developer console, add the following parameters to the URL:

Display debug information


Display event debug information