Mongoid::Included

gem 'mongoid-included'

$ gem install mongoid-included

# Include the helper module
include Mongoid::DocumentInclusion

# Define parent document in embedded class
included_in :invoice

# Define embedded relation in parent document
includes_many :items
includes_one :user

class Invoice
	include Mongoid::Document
	
	includes_many :items
end

# This will generate a Mongoid Relation with the following signature:
	embeds_many :items, :class_name => Invoice::Item

class Invoice::Item
	include Mongoid::Document

	included_in :invoice
end
# This will generate the following code:
	extend ActiveModel::Naming
	# Overriding .model_name so rails recognizes the class as __Item__ and generate more convenient urls.
	def self.model_name
		if self.parent != Object
			ActiveModel::Name.new(self, self.parent)
		else
			super
		end
	end
	
	embedded_in :invoice

# Define routes with the embedded document as a nested resource
resources :invoices do
	resources :items
end

# if you decide that the controller should also use namespaces, place the __items_controller__ inside an __invoices__ folder and use:
resources :invoices do
	resources :items, :module => :invoices
end