Agile Web Development with Rails, Edition 5

6.2 Iteration A2: Making Prettier Listings 2 Instant Gratification

6.1 Iteration A1: Creating the Products Maintenance Application

</\d+ (test|run)s, \d+ assertions, 0 failures, 0 errors/> expected to be =~
<"<pre class=\"stderr\">Expected string default value for '--jbuilder'; got true (boolean)</pre>">.

Traceback:
  /home/rubys/git/awdwr/edition4/checkdepot.rb:70:in `block (3 levels) in <class:DepotTest>'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/nokogiri-1.7.0.1/lib/nokogiri/xml/node_set.rb:187:in `block in each'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/nokogiri-1.7.0.1/lib/nokogiri/xml/node_set.rb:186:in `upto'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/nokogiri-1.7.0.1/lib/nokogiri/xml/node_set.rb:186:in `each'
  /home/rubys/git/awdwr/edition4/checkdepot.rb:69:in `block (2 levels) in <class:DepotTest>'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/rails-dom-testing-2.0.2/lib/rails/dom/testing/assertions/selector_assertions.rb:286:in `nest_selection'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/rails-dom-testing-2.0.2/lib/rails/dom/testing/assertions/selector_assertions.rb:175:in `block in assert_select'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/rails-dom-testing-2.0.2/lib/rails/dom/testing/assertions/selector_assertions.rb:171:in `tap'
  /home/rubys/.rvm/gems/ruby-2.2.5/gems/rails-dom-testing-2.0.2/lib/rails/dom/testing/assertions/selector_assertions.rb:171:in `assert_select'
  /home/rubys/git/awdwr/edition4/checkdepot.rb:67:in `block in <class:DepotTest>'

This section mostly covers database configuration options for those users that insist on using MySQL. SQLite3 users will skip most of it.

Create the application.

bundle exec /home/rubys/git/rails/railties/exe/rails new depot --skip-bundle --skip-listen
      create  
      create  README.md
      create  Rakefile
      create  config.ru
      create  .gitignore
      create  Gemfile
      create  app
      create  app/assets/config/manifest.js
      create  app/assets/javascripts/application.js
      create  app/assets/javascripts/cable.js
      create  app/assets/stylesheets/application.css
      create  app/channels/application_cable/channel.rb
      create  app/channels/application_cable/connection.rb
      create  app/controllers/application_controller.rb
      create  app/helpers/application_helper.rb
      create  app/jobs/application_job.rb
      create  app/mailers/application_mailer.rb
      create  app/models/application_record.rb
      create  app/views/layouts/application.html.erb
      create  app/views/layouts/mailer.html.erb
      create  app/views/layouts/mailer.text.erb
      create  app/assets/images/.keep
      create  app/assets/javascripts/channels
      create  app/assets/javascripts/channels/.keep
      create  app/controllers/concerns/.keep
      create  app/models/concerns/.keep
      create  bin
      create  bin/bundle
      create  bin/rails
      create  bin/rake
      create  bin/setup
      create  bin/update
      create  config
      create  config/routes.rb
      create  config/application.rb
      create  config/environment.rb
      create  config/secrets.yml
      create  config/cable.yml
      create  config/puma.rb
      create  config/spring.rb
      create  config/environments
      create  config/environments/development.rb
      create  config/environments/production.rb
      create  config/environments/test.rb
      create  config/initializers
      create  config/initializers/application_controller_renderer.rb
      create  config/initializers/assets.rb
      create  config/initializers/backtrace_silencers.rb
      create  config/initializers/cookies_serializer.rb
      create  config/initializers/cors.rb
      create  config/initializers/filter_parameter_logging.rb
      create  config/initializers/inflections.rb
      create  config/initializers/mime_types.rb
      create  config/initializers/new_framework_defaults.rb
      create  config/initializers/session_store.rb
      create  config/initializers/wrap_parameters.rb
      create  config/locales
      create  config/locales/en.yml
      create  config/boot.rb
      create  config/database.yml
      create  db
      create  db/seeds.rb
      create  lib
      create  lib/tasks
      create  lib/tasks/.keep
      create  lib/assets
      create  lib/assets/.keep
      create  log
      create  log/.keep
      create  public
      create  public/404.html
      create  public/422.html
      create  public/500.html
      create  public/apple-touch-icon-precomposed.png
      create  public/apple-touch-icon.png
      create  public/favicon.ico
      create  public/robots.txt
      create  test/fixtures
      create  test/fixtures/.keep
      create  test/fixtures/files
      create  test/fixtures/files/.keep
      create  test/controllers
      create  test/controllers/.keep
      create  test/mailers
      create  test/mailers/.keep
      create  test/models
      create  test/models/.keep
      create  test/helpers
      create  test/helpers/.keep
      create  test/integration
      create  test/integration/.keep
      create  test/test_helper.rb
      create  tmp
      create  tmp/.keep
      create  tmp/cache
      create  tmp/cache/assets
      create  vendor/assets/javascripts
      create  vendor/assets/javascripts/.keep
      create  vendor/assets/stylesheets
      create  vendor/assets/stylesheets/.keep
      remove  config/initializers/cors.rb
bundle install --local
Resolving dependencies...
Using rake 12.0.0
Using concurrent-ruby 1.0.4
Using i18n 0.8.0
Using minitest 5.9.1
Using thread_safe 0.3.5
Using builder 3.2.3
Using erubis 2.7.0
Using mini_portile2 2.1.0
Using rack 2.0.1
Using nio4r 2.0.0
Using websocket-extensions 0.1.2
Using mime-types-data 3.2016.0521
Using arel 7.1.4
Using bundler 1.14.4
Using byebug 9.0.6
Using coffee-script-source 1.12.2
Using execjs 2.7.0
Using method_source 0.8.2
Using thor 0.19.4
Using debug_inspector 0.0.2
Using ffi 1.9.17
Using multi_json 1.12.1
Using pg 0.19.0
Using puma 3.7.0
Using sass 3.4.23
Using tilt 2.0.6
Using sqlite3 1.3.13
Using turbolinks-source 5.0.0
Using tzinfo 1.2.2
Using nokogiri 1.7.0.1
Using rack-test 0.6.3
Using sprockets 3.7.1
Using websocket-driver 0.6.5
Using mime-types 3.1
Using coffee-script 2.4.1
Using uglifier 3.0.4
Using rb-inotify 0.9.7 from source at `/home/rubys/git/rb-inotify`
Using queue_classic 3.2.0.RC1 from source at `/home/rubys/git/queue_classic`
Using turbolinks 5.0.1
Using activesupport 5.0.1 from source at `/home/rubys/git/rails`
Using loofah 2.0.3
Using mail 2.6.4
Using rails-dom-testing 2.0.2
Using globalid 0.3.7
Using activemodel 5.0.1 from source at `/home/rubys/git/rails`
Using jbuilder 2.6.1
Using spring 2.0.1
Using rails-html-sanitizer 1.0.3
Using activejob 5.0.1 from source at `/home/rubys/git/rails`
Using activerecord 5.0.1 from source at `/home/rubys/git/rails`
Using actionview 5.0.1 from source at `/home/rubys/git/rails`
Using actionpack 5.0.1 from source at `/home/rubys/git/rails`
Using actioncable 5.0.1 from source at `/home/rubys/git/rails`
Using actionmailer 5.0.1 from source at `/home/rubys/git/rails`
Using railties 5.0.1 from source at `/home/rubys/git/rails`
Using sprockets-rails 3.2.0
Using coffee-rails 4.2.1
Using jquery-rails 4.2.2
Using web-console 3.4.0 from source at `/home/rubys/git/web-console`
Using rails 5.0.1 from source at `/home/rubys/git/rails`
Using sass-rails 5.0.6
Bundle complete! 15 Gemfile dependencies, 61 gems now installed.
Use `bundle show [gemname]` to see where a bundled gem is installed.

Look at the files created.

ls -p
app/  config/	 db/	  Gemfile.lock	log/	 Rakefile   test/  vendor/
bin/  config.ru  Gemfile  lib/		public/  README.md  tmp/

Generate scaffolding for a real model, modify a template, and do our first bit of data entry.

Generating our first model and associated scaffolding

rails generate scaffold Product title:string description:text image_url:string price:decimal
Expected string default value for '--jbuilder'; got true (boolean)
      invoke  active_record
      create    db/migrate/20170215144043_create_products.rb
      create    app/models/product.rb
      invoke    test_unit
      create      test/models/product_test.rb
      create      test/fixtures/products.yml
      invoke  resource_route
       route    resources :products
      invoke  scaffold_controller
      create    app/controllers/products_controller.rb
      invoke    erb
      create      app/views/products
      create      app/views/products/index.html.erb
      create      app/views/products/edit.html.erb
      create      app/views/products/show.html.erb
      create      app/views/products/new.html.erb
      create      app/views/products/_form.html.erb
      invoke    test_unit
      create      test/controllers/products_controller_test.rb
      invoke    helper
      create      app/helpers/products_helper.rb
      invoke      test_unit
      invoke    jbuilder
      create      app/views/products/index.json.jbuilder
      create      app/views/products/show.json.jbuilder
      create      app/views/products/_product.json.jbuilder
      invoke  assets
      invoke    coffee
      create      app/assets/javascripts/products.coffee
      invoke    scss
      create      app/assets/stylesheets/products.scss
      invoke  scss
      create    app/assets/stylesheets/scaffolds.scss

Break lines for formatting reasons

edit app/controllers/products_controller.rb
class ProductsController < ApplicationController
  before_action :set_product, only: [:show, :edit, :update, :destroy]
 
  # GET /products
  # GET /products.json
  def index
    @products = Product.all
  end
 
  # GET /products/1
  # GET /products/1.json
  def show
  end
 
  # GET /products/new
  def new
    @product = Product.new
  end
 
  # GET /products/1/edit
  def edit
  end
 
  # POST /products
  # POST /products.json
  def create
    @product = Product.new(product_params)
 
    respond_to do |format|
      if @product.save
        format.html { redirect_to @product,
          notice: 'Product was successfully created.' }
        format.json { render :show, status: :created,
          location: @product }
      else
        format.html { render :new }
        format.json { render json: @product.errors,
          status: :unprocessable_entity }
      end
    end
  end
 
  # PATCH/PUT /products/1
  # PATCH/PUT /products/1.json
  def update
    respond_to do |format|
      if @product.update(product_params)
        format.html { redirect_to @product,
          notice: 'Product was successfully updated.' }
        format.json { render :show, status: :ok, location: @product }
      else
        format.html { render :edit }
        format.json { render json: @product.errors,
          status: :unprocessable_entity }
      end
    end
  end
 
  # DELETE /products/1
  # DELETE /products/1.json
  def destroy
    @product.destroy
    respond_to do |format|
      format.html { redirect_to products_url,
          notice: 'Product was successfully destroyed.' }
      format.json { head :no_content }
    end
  end
 
  private
    # Use callbacks to share common setup or constraints between actions.
    def set_product
      @product = Product.find(params[:id])
    end
 
    # Never trust parameters from the scary internet, only allow the white
    # list through.
    def product_params
      params.require(:product).permit(:title, :description, :image_url, :price)
    end
end
edit app/views/products/index.html.erb
<p id="notice"><%= notice %></p>
 
<h1>Products</h1>
 
<table>
  <thead>
    <tr>
      <th>Title</th>
      <th>Description</th>
      <th>Image url</th>
      <th>Price</th>
      <th colspan="3"></th>
    </tr>
  </thead>
 
  <tbody>
    <% @products.each do |product| %>
      <tr>
        <td><%= product.title %></td>
        <td><%= product.description %></td>
        <td><%= product.image_url %></td>
        <td><%= product.price %></td>
        <td><%= link_to 'Show', product %></td>
        <td><%= link_to 'Edit', edit_product_path(product) %></td>
        <td><%= link_to 'Destroy', product,
            method: :delete, data: { confirm: 'Are you sure?' } %></td>
      </tr>
    <% end %>
  </tbody>
</table>
 
<br>
 
<%= link_to 'New Product', new_product_path %>

Add precision and scale to the price

edit db/migrate/20170215144043_create_products.rb
class CreateProducts < ActiveRecord::Migration[5.0]
  def change
    create_table :products do |t|
      t.string :title
      t.text :description
      t.string :image_url
      t.decimal :price, precision: 8, scale: 2
 
      t.timestamps
    end
  end
end

Apply the migration

rails db:migrate
mv 20170215144043_create_products.rb 20170215000001_create_products.rb
== 20170215000001 CreateProducts: migrating ===================================
-- create_table(:products)
   -> 0.0012s
== 20170215000001 CreateProducts: migrated (0.0013s) ==========================
 

Restart the server.

Get an (empty) list of products

get /products

Products

Title Description Image url Price

New Product

Show (and modify) one of the templates produced

edit app/views/products/_form.html.erb
<%= form_for(product) do |f| %>
  <% if product.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(product.errors.count, "error") %>
      prohibited this product from being saved:</h2>
 
      <ul>
      <% product.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
 
  <div class="field">
    <%= f.label :title %>
    <%= f.text_field :title %>
  </div>
 
  <div class="field">
    <%= f.label :description %>
    <%= f.text_area :description, rows: 10, cols: 60 %>
  </div>
 
  <div class="field">
    <%= f.label :image_url %>
    <%= f.text_field :image_url %>
  </div>
 
  <div class="field">
    <%= f.label :price %>
    <%= f.text_field :price %>
  </div>
 
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

Create a product

get /products/new

New Product

Back
post /products
You are being redirected.
get http://localhost:3000/products/1

Product was successfully created.

Title: Seven Mobile Apps in Seven Weeks

Description: <p> <em>Native Apps, Multiple Platforms</em> Answer the question “Can we build this for ALL the devices?” with a resounding YES. This book will help you get there with a real-world introduction to seven platforms, whether you’re new to mobile or an experienced developer needing to expand your options. Plus, you’ll find out which cross-platform solution makes the most sense for your needs. </p>

Image url: 7apps.jpg

Price: 29.0

Edit | Back

Verify that the product has been added

get /products

Products

Title Description Image url Price
Seven Mobile Apps in Seven Weeks <p> <em>Native Apps, Multiple Platforms</em> Answer the question “Can we build this for ALL the devices?” with a resounding YES. This book will help you get there with a real-world introduction to seven platforms, whether you’re new to mobile or an experienced developer needing to expand your options. Plus, you’ll find out which cross-platform solution makes the most sense for your needs. </p> 7apps.jpg 29.0 Show Edit Destroy

New Product

And, just to verify that we haven't broken anything

rails test
Run options: --seed 17138
 
# Running:
 
.......
 
Finished in 0.584438s, 11.9773 runs/s, 15.3994 assertions/s.
 
7 runs, 9 assertions, 0 failures, 0 errors, 0 skips

6.2 Iteration A2: Making Prettier Listings 2 Instant Gratification