Constraints in routes

constraints.rb

# config/initializers/contraints.rb

module Constraints
  class Subdomain
    def self.matches?(request)
      request.subdomain.present? && request.subdomain != 'www'
    end
  end
  
  class SignedIn
    def self.matches?(request)
      !!request.session[:user_id]
      # !!request.cookies['user_id']
    end
  end
end  

routes.rb

Sample::Application.routes.draw do
  constraints Constraints::SignedIn do
    get '/' => 'items#index'
  end
  root 'dashboard#index'
end