Class: Usmu::Plugin

Inherits:
Object
  • Object
show all
Defined in:
lib/usmu/plugin.rb,
lib/usmu/plugin/core.rb

Defined Under Namespace

Classes: Core

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Plugin

Returns a new instance of Plugin.



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# File 'lib/usmu/plugin.rb', line 4

def initialize
  @log = Logging.logger['Usmu::Plugin']
end

Instance Attribute Details

#plugins ⇒ Array (readonly)

Returns a list of all plugins discovered and loaded.

Returns:

  • (Array) —

    a list of all plugins discovered and loaded.



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# File 'lib/usmu/plugin.rb', line 35

def plugins
  @plugins ||= []
end

Instance Method Details

#invoke(method, *args) ⇒ Object

Call all plugins and collate any data returned. nil can be returned explicitly to say this plugin has nothing to return.

Parameters:

  • method (Symbol) —

    The name of the method to call. This should be namespaced somehow. For example, a plugin called usmu-s3 could use the method namespace s3 and have a hook called :s3_upload

  • args (Array) —

    The arguments to pass through to plugins. Can be empty.



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# File 'lib/usmu/plugin.rb', line 44

def invoke(method, *args)
  @log.debug("Invoking plugin API #{method}")
  plugins.map do |p|
    if p.respond_to? method
      @log.debug("Sending message to #{p.class.name}")
      p.public_send method, *args
    else
      nil
    end
  end.select {|i| i}
end

#load_plugins

This method returns an undefined value.

Loads all plugins that are available as gems. This is determined by looking at the gem's name. Anything prefixed with the string 'usmu-' will be recognised as a plugin. This will load the gem according to the RubyGems recommendations for naming schemes. A gem named usmu-s3_uploader will be loaded by requiring the path 'usmu/s3_uploader' and then then the class Usmu::S3Uploader will be instantiated as the plugins interface.



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# File 'lib/usmu/plugin.rb', line 14

def load_plugins
  loaded = []
  @log.debug('Loading plugins')
  @log.debug('Loaded Usmu::Plugin::Core')
  plugins.push Usmu::Plugin::Core.new
  Gem::Specification.find_all { |s| s.name =~ /^usmu-/ }.each do |spec|
    load_path = spec.name.gsub('-', '/')
    require load_path

    unless loaded.include? load_path
      loaded << load_path
      klass = load_path.split('/').map {|s| s.split('_').map(&:capitalize).join }.join('::')
      @log.debug("Loading plugin #{klass} from '#{load_path}'")
      plugins.push plugin_get(klass)
    end
  end
  @log.debug("Loaded: #{plugins.inspect}")
end

#plugin_get(klass) ⇒ Object (private) 



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# File 'lib/usmu/plugin.rb', line 58

def plugin_get(klass)
  object.const_get(klass).new
rescue NameError
  # Ruby 1.9.3, dowp
  klass.split('::').reduce(Object) {|memo, o| memo.const_get o }.new
end