Dynos - an alternative to NBB Engines. Namespaced controller methods available in any controller.

dynos

# app/controllers/application_controller.rb
class ApplicationController < ActionController::Base

  # ...

  before_filter :update_dyno
  def dyno
    @@dyno_set ||= DynoSet.new
  end
  
  def update_dyno
    dyno.update_controller(self)
  end
end

# app/controllers/home_controller.rb
class HomeController < ApplicationController
  def index
    # NOTE: I prefer dyno.widget_list as opposed to widget_list with a method_missing in ApplicationController -- it is clear where the method is located.
    @widgets = dyno.widget_list 
    @accounts = dyno["accounts"].account_list
  end
end

# app/controllers/accounts_controller.rb
class AccountsController < ApplicationController
  def index
    @widgets = dyno["widgets"].widget_list
    @accounts = dyno.account_list
  end
end

# app/dynos/home_dyno.rb
class HomeDyno < Dyno
  def widget_list
    # ...
  end
end

# app/dynos/accounts_dyno.rb
class AccountsDyno < Dyno
  def account_list
    # ...
    if params[:sort] == "balance" # NOTE: can use params here, which is defined in controller...
      # ...
    end
  end
end

# lib/dyno.rb
class Dyno
  def initialize(parent)
    @parent_controller = parent
  end
  
  def update_controller(parent)
    @parent_controller = parent
  end
  
  # If a dyno can't handle the method, send it to the corresponding controller.
  def method_missing(method, *args, &proc)
    @parent_controller.send(method, *args, &proc)
  end
end

class DynoSet
  def initialize
    @dynos = {}
  end
  
  def update_controller(parent)
    @parent_controller = parent
    @dynos.each_pair do |k, v|
      v.update_controller(parent)
    end
  end
  
  def [](cont_str)
    raise Exception, "parent controller not set!" unless @parent_controller
    @dynos[cont_str.to_s] ||= "#{cont_str.camelize}Dyno".constantize.new(@parent_controller)
  end
  
  # If we ask the dynoset for a method, assume it's on the current controller (based on params).  Ask that dyno.
  def method_missing(method, *args, &proc)
    raise Exception, "parent controller not set!" unless @parent_controller
    self[@parent_controller.params[:controller]].send(method, *args, &proc)
  end
end