Custom Commands

Infinispan makes use of a command/visitor pattern to implement the various top-level methods you see on the public-facing API.  This is explained in further detail in the Architectural Overview on the Infinispan public wiki.  However, these commands - and their corresponding visitors - are hard-coded as a part of Infinispan's core module, making it impossible for module authors to extend and enhance Infinispan to create new arbitrary commands and visitors.

However, since Infinispan 5.0, this capability has now been added.  As a module author (such as infinispan-tree, infinispan-query, etc.) you can now define your own commands. From Infinispan 5.1 onwards, you do so by:

1. Create a META-INF/services/org.infinispan.commands.module.ModuleCommandExtensions file and ensure this is packaged in your jar.

2. Implementing ModuleCommandFactory and ModuleCommandInitializer from infinispan-core.

3. Implementing ModuleCommandExtensions from infinispan-core.

4. Specifing the fully-qualified class name of the ModuleCommandExtensions implementation in META-INF/services/org.infinispan.commands.module.ModuleCommandExtensions.

5. Implement your custom commands and visitors for these commands

Here is an example of an META-INF/services/org.infinispan.commands.module.ModuleCommandExtensions file, configured accordingly:Code Snippet error: Unable to retrieve the URL: https://github.com/infinispan/infinispan/raw/master/query/src/main/resources/META-INF/services/org.infinispan.commands.module.ModuleCommandExtensions status code: 404.

For a full, working example of a sample module that makes use of custom commands and visitors, check out Infinispan Sample Module.