Agile Web Development with Rails, Edition 4

6.2 Iteration A2: Making Prettier Listings 2 Instant Gratification

6.1 Iteration A1: Creating the Products Maintenance Application

RuntimeError: Edit app/controllers/products_controller.rb failed at makedepot.rb:158

Traceback:
  

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/bin/rails new depot --skip-bundle
      create  
      create  README.rdoc
      create  Rakefile
      create  config.ru
      create  .gitignore
      create  Gemfile
      create  app
      create  app/assets/javascripts/application.js
      create  app/assets/stylesheets/application.css
      create  app/controllers/application_controller.rb
      create  app/helpers/application_helper.rb
      create  app/views/layouts/application.html.erb
      create  app/assets/images/.keep
      create  app/mailers/.keep
      create  app/models/.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  config
      create  config/routes.rb
      create  config/application.rb
      create  config/environment.rb
      create  config/secrets.yml
      create  config/environments
      create  config/environments/development.rb
      create  config/environments/production.rb
      create  config/environments/test.rb
      create  config/initializers
      create  config/initializers/assets.rb
      create  config/initializers/backtrace_silencers.rb
      create  config/initializers/cookies_serializer.rb
      create  config/initializers/filter_parameter_logging.rb
      create  config/initializers/inflections.rb
      create  config/initializers/mime_types.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/favicon.ico
      create  public/robots.txt
      create  test/fixtures
      create  test/fixtures/.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/cache
      create  tmp/cache/assets
      create  vendor/assets/javascripts
      create  vendor/assets/javascripts/.keep
      create  vendor/assets/stylesheets
      create  vendor/assets/stylesheets/.keep
bundle install --local
Resolving dependencies...
Using rake 10.4.2
Using i18n 0.7.0.beta1
Using json 1.8.1
Using minitest 5.5.0
Using thread_safe 0.3.4
Using tzinfo 1.2.2
Using activesupport 5.0.0.alpha from source at /home/rubys/git/rails
Using builder 3.2.2
Using erubis 2.7.0
Using mini_portile 0.6.1
Using nokogiri 1.6.5
Using rails-deprecated_sanitizer 1.0.3
Using rails-dom-testing 1.0.5
Using loofah 2.0.1
Using rails-html-sanitizer 1.0.1
Using actionview 5.0.0.alpha from source at /home/rubys/git/rails
Using rack 1.6.0.beta2
Using rack-test 0.6.2
Using actionpack 5.0.0.alpha from source at /home/rubys/git/rails
Using globalid 0.3.0
Using activejob 5.0.0.alpha from source at /home/rubys/git/rails
Using mime-types 2.4.3
Using mail 2.6.3
Using actionmailer 5.0.0.alpha from source at /home/rubys/git/rails
Using activemodel 5.0.0.alpha from source at /home/rubys/git/rails
Using arel 6.0.0 from source at /home/rubys/git/arel
Using activerecord 5.0.0.alpha from source at /home/rubys/git/rails
Using debug_inspector 0.0.2
Using binding_of_caller 0.7.2
Using bundler 1.7.9
Using columnize 0.9.0
Using debugger-linecache 1.2.0
Using slop 3.6.0
Using byebug 3.5.1
Using coffee-script-source 1.8.0
Using execjs 2.2.2
Using coffee-script 2.3.0
Using thor 0.19.1
Using railties 5.0.0.alpha from source at /home/rubys/git/rails
Using coffee-rails 4.1.0 from source at /home/rubys/git/coffee-rails
Using hike 1.2.3
Using multi_json 1.10.1
Using jbuilder 2.2.5
Using jquery-rails 4.0.0 from source at /home/rubys/git/jquery-rails
Using qu 0.2.0 from source at /home/rubys/git/qu-rails
Using qu-rails 0.2.0 from source at /home/rubys/git/qu-rails
Using tilt 1.4.1
Using sprockets 2.12.3
Using sprockets-rails 2.2.2
Using rails 5.0.0.alpha from source at /home/rubys/git/rails
Using rdoc 4.2.0
Using sass 3.4.9
Using sass-rails 5.0.0
Using sdoc 0.4.1
Using spring 1.2.0
Using sqlite3 1.3.10
Using turbolinks 2.5.3
Using uglifier 2.6.0
Using web-console 2.0.0 from source at /home/rubys/git/web-console
Your bundle is complete!
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.rdoc  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
      invoke  active_record
      create    db/migrate/20141215144034_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  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
#<IndexError: regexp not matched>
  /home/rubys/git/gorp/lib/gorp/edit.rb:150:in `[]='
  /home/rubys/git/gorp/lib/gorp/edit.rb:150:in `msub'
  makedepot.rb:158:in `block (3 levels) in <main>'
  /home/rubys/git/gorp/lib/gorp/edit.rb:111:in `instance_exec'
  /home/rubys/git/gorp/lib/gorp/edit.rb:111:in `block in dcl'
  /home/rubys/git/gorp/lib/gorp/edit.rb:109:in `sub!'
  /home/rubys/git/gorp/lib/gorp/edit.rb:109:in `dcl'
  makedepot.rb:156:in `block (2 levels) in <main>'
  /home/rubys/git/gorp/lib/gorp/edit.rb:173:in `instance_exec'
  /home/rubys/git/gorp/lib/gorp/edit.rb:173:in `edit'
  makedepot.rb:155:in `block in <main>'
  /home/rubys/git/gorp/lib/gorp/output.rb:59:in `call'
  /home/rubys/git/gorp/lib/gorp/output.rb:59:in `block (4 levels) in <top (required)>'
  /home/rubys/git/gorp/lib/gorp/output.rb:49:in `each'
  /home/rubys/git/gorp/lib/gorp/output.rb:49:in `block (3 levels) in <top (required)>'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:175:in `call'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:175:in `_nested_structures'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:68:in `tag!'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:93:in `method_missing'
  /home/rubys/git/gorp/lib/gorp/output.rb:22:in `block (2 levels) in <top (required)>'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:175:in `call'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:175:in `_nested_structures'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:68:in `tag!'
  /home/rubys/.rvm/gems/ruby-2.1.5/gems/builder-3.2.2/lib/builder/xmlbase.rb:93:in `method_missing'
  /home/rubys/git/gorp/lib/gorp/output.rb:11:in `block in <top (required)>'
    
class ProductsController < ApplicationController
  before_action :set_product, only: [:show, :edit, :update, :destroy]
 
  # GET /products
  def index
    @products = Product.all
  end
 
  # GET /products/1
  def show
  end
 
  # GET /products/new
  def new
    @product = Product.new
  end
 
  # GET /products/1/edit
  def edit
  end
 
  # POST /products
  def create
    @product = Product.new(product_params)
 
    if @product.save
      redirect_to @product, notice: 'Product was successfully created.'
    else
      render :new
    end
  end
 
  # PATCH/PUT /products/1
  def update
    if @product.update(product_params)
      redirect_to @product, notice: 'Product was successfully updated.'
    else
      render :edit
    end
  end
 
  # DELETE /products/1
  def destroy
    @product.destroy
    redirect_to products_url, notice: 'Product was successfully destroyed.'
  end
 
  private
    # Use callbacks to share common setup or constraints between actions.
    def set_product
      @product = Product.find(params[:id])
    end
 
    # Only allow a trusted parameter "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>Listing 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/20141215144034_create_products.rb
class CreateProducts < ActiveRecord::Migration
  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 null: false
    end
  end
end

Apply the migration

rake db:migrate
mv 20141215144034_create_products.rb 20141215000001_create_products.rb
== 20141215000001 CreateProducts: migrating ===================================
-- create_table(:products)
   -> 0.0008s
== 20141215000001 CreateProducts: migrated (0.0008s) ==========================
 

Restart the server.

Get an (empty) list of products

get /products

Listing 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 %><br>
    <%= f.text_field :title %>
  </div>
  <div class="field">
    <%= f.label :description %><br>
    <%= f.text_area :description, rows: 6 %>
  </div>
  <div class="field">
    <%= f.label :image_url %><br>
    <%= f.text_field :image_url %>
  </div>
  <div class="field">
    <%= f.label :price %><br>
    <%= 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: CoffeeScript

Description: <p> CoffeeScript is JavaScript done right. It provides all of JavaScript's functionality wrapped in a cleaner, more succinct syntax. In the first book on this exciting new language, CoffeeScript guru Trevor Burnham shows you how to hold onto all the power and flexibility of JavaScript while writing clearer, cleaner, and safer code. </p>

Image url: cs.jpg

Price: 29.0

Edit | Back

Verify that the product has been added

get /products

Listing Products

Title Description Image url Price
CoffeeScript <p> CoffeeScript is JavaScript done right. It provides all of JavaScript's functionality wrapped in a cleaner, more succinct syntax. In the first book on this exciting new language, CoffeeScript guru Trevor Burnham shows you how to hold onto all the power and flexibility of JavaScript while writing clearer, cleaner, and safer code. </p> cs.jpg 29.0 Show Edit Destroy

New Product

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

rake test
Run options: --seed 48597
 
# Running:
 
.......
 
Finished in 0.392206s, 17.8477 runs/s, 33.1458 assertions/s.
 
7 runs, 13 assertions, 0 failures, 0 errors, 0 skips

6.2 Iteration A2: Making Prettier Listings 2 Instant Gratification