Small configuration DSL

configuration.rb

module Foo
  module Configuration
    require 'ostruct'
    extend ActiveSupport::Concern

    included do
      #
    end

    module ClassMethods
      def method_missing(method_name, *args)
        @config ||= OpenStruct.new
        
        if method_name.to_s.match(/^.+=$/)
          @config.send(method_name, args.first)
        else
          @config.send(method_name)
        end
      end

      def configure
        yield self
      end
    end

  end
end

# Usage

module App
  include Foo::Configuration
end

App.configure do |config|
   config.test_value = :test
end