Plugins

Plugins are actually system modules. An assembly, then, is a grouping of modules that provides a Geronimo server instance with its feature set. Assemblies are the different ways you can create a server out of the various modules available. Plugins are very dependent and sensitive to server versions. As such, plugins that are compiled against one server version (like Geronimo 2.1) might not deploy or function correctly in new releases (such as Geronimo 2.1.3). Just as you must redeploy your applications when migrating to updated server releases, you must regenerate any existing plugins for different server levels. Last but not least, when installing plugins you need Internet access so the plugin installer can retrieve all the necessary dependencies from the online repositories.

Starting with Geronimo 2.2, the servers are assembled entirely out of plugins.

• Most plugins are modules, describing a classloader and services and possibly containing classes and resources.
• Plugins also contain descriptive information and include additional instructions on how the plugin fits into a server.
• Information about multiple plugins can be collected into a plugin catalog, often located in a maven repository
• A plugin repository is basically a plugin catalog together with a maven-structured repository containing plugins.
• Plugins can be installed from a plugin repository into an existing Geronimo server using GShell commands or the Geronimo Administration Console.
• Plugin metadata for an existing plugin in a Geronimo server can be edited (to some extent) in the administrative console.
• A new server containing a specified set of plugins can be extracted from an existing server using GShell commands or the Geronimo Administration Console.
• The dependency system assures that the resulting server has all needed plugins to operate.