Applying before_action to entire namespace sample

namespace-before-action-sample.rb

# config/routes.rb
namespace :admin do
  get 'dashboard' => 'dashboard#index'
end

# app/controllers/admin/admin_controller.rb
include SessionsHelper

class Admin::AdminController < ApplicationController
  http_basic_authenticate_with name: "johndoe", password: "secret"
  before_action :require_login

  private

  def require_login
    unless logged_in?
      redirect_to '/login'
    end
  end
end

# app/controllers/admin/dashboard_controller.rb
class Admin::DashboardController < Admin::AdminController
  def index
  end
end