Plugin Support

Warning, the plugin support in Moonshot is a work-in-progress. The interface to plugins may change dramatically in future versions.

Moonshot supports adding plugins (implemented as a Ruby class) to the controller that can perform actions before and after the create, update, delete, deploy, status, doctor and ssh actions.

Writing a Moonshot Plugin

A Moonshot Plugin is a Ruby class that responds to one or more of the following methods:

  • pre_create
  • post_create
  • pre_update
  • post_update
  • pre_delete
  • post_delete
  • pre_deploy
  • post_deploy
  • pre_status
  • post_status
  • pre_doctor
  • post_doctor
  • pre_ssh
  • post_ssh

The method will be handed a single argument, which is an instance of the Moonshot::Resources class. This instance gives the plugin access to three important resources:

  • Moonshot::Resources#ilog is an instance of InteractiveLogger, used to display status to the user of the CLI interface.
  • Moonshot::Resources#stack is an instance of Moonshot::Stack which can retreive the name of the stack, stack parameters and stack outputs. This support should be expanded in the future to provide Plugins with more control over the CloudFormation stack.

Adding a plugin to a CLI tool.

Once you have defined or included your plugin class, you can add a plugin by modifying your Moonfile.rb file, like so:

Moonshot.config do |c|
  c.app_name = 'my-app'
  # ...
  c.plugins <<

Auto-loading Plugin Source

The Moonshot CLI tool will auto-load plugin source in the path moonshot/plugins/**/*.rb relative to the Moonfile.rb file for your project. This can be useful for plugins that define project-specific behaviors.