Agile Web Development with Rails, Edition 4

9.1 Iteration D1: Finding a Cart

Create a cart. Put it in a session. Find it.

Create a cart.

rails generate scaffold Cart

      invoke  active_record

      create    db/migrate/20121011071231_create_carts.rb

      create    app/models/cart.rb

      invoke    test_unit

      create      test/unit/cart_test.rb

      create      test/fixtures/carts.yml

      invoke  resource_route

       route    resources :carts

      invoke  scaffold_controller

      create    app/controllers/carts_controller.rb

      invoke    erb

      create      app/views/carts

      create      app/views/carts/index.html.erb

      create      app/views/carts/edit.html.erb

      create      app/views/carts/show.html.erb

      create      app/views/carts/new.html.erb

      create      app/views/carts/_form.html.erb

      invoke    test_unit

      create      test/functional/carts_controller_test.rb

      invoke    helper

      create      app/helpers/carts_helper.rb

      invoke      test_unit

      create        test/unit/helpers/carts_helper_test.rb

      invoke  assets

      invoke    coffee

      create      app/assets/javascripts/carts.js.coffee

      invoke    scss

      create      app/assets/stylesheets/carts.css.scss

      invoke  scss

   identical    app/assets/stylesheets/scaffolds.css.scss

rake db:migrate

mv 20121011071231_create_carts.rb 20110711000002_create_carts.rb

==  CreateCarts: migrating ====================================================

-- create_table(:carts)

   -> 0.0188s

==  CreateCarts: migrated (0.0844s) ===========================================

Implement current_cart, which creates a new cart if it can't find one.

edit app/controllers/application_controller.rb

class ApplicationController < ActionController::Base

  protect_from_forgery

  private

    def current_cart

      Cart.find(session[:cart_id])

    rescue ActiveRecord::RecordNotFound

      cart = Cart.create

      session[:cart_id] = cart.id

      cart

end

end