Comandos para auxilio do minicurso de introdução ao Ruby on Rails

_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 :name %><br>
    <%= f.text_field :name %>
  </div>

  <div class="field">
    <%= f.label :description %><br>
    <%= f.text_area :description %>
  </div>

  <div class="field">
    <%= f.label :category_id %><br>
    <%= f.select :category_id, Category.all.map { |c| [c.name, c.id] } %>
  </div>

  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

category.rb

class Category < ActiveRecord::Base
  has_many :products
  
  validates :name, presence: true, uniqueness: true
end

category_spec.rb

require 'rails_helper'

RSpec.describe Category, type: :model do
  describe 'validations' do
    context 'name' do
      it 'presence' do
        category = FactoryGirl.build(:category, name: nil)

        expect(category.valid?).to_not be_truthy
        expect(category.errors.messages[:name].size).to eq(1)
      end

      it 'uniqueness' do
        persisted_category = FactoryGirl.create(:category)
        category = persisted_category.dup

        expect(category.valid?).to_not be_truthy
        expect(category.errors.messages[:name].size).to eq(1)
      end
    end
  end
end

comandos.md

habilitando uso da rvm no terminal do gnome

Leia esse link caso seu terminal não reconheça os comandos da rvm

pra instalar a rvm

Script ou Comandos

clonando o template

git clone [email protected]:gbpereira/rails-template.git seccomp-app

selecionando a versão do ruby e o gemset do projeto

rvm use 2.2.3@seccomp

criando o crud básico de Categorias

rails g scaffold category name:string

criando o model de Produtos

rails g model product name:string description:text category:references

criando o controller de Produtos

rails g controller products --skip-assets --no-helper

rodando as migrations pendentes

rake db:migrate (desenvolvimento) rake db:migrate RAILS_ENV=test (teste)

index.html.erb

<p id="notice"><%= notice %></p>

<h1>Listing Products</h1>

<table>
  <thead>
    <tr>
      <th>Name</th>
      <th>Description</th>
      <th>Category</th>
      <th></th>
    </tr>
  </thead>

  <tbody>
    <% @products.each do |product| %>
      <tr>
        <td><%= product.name %></td>
        <td><%= product.description %></td>
        <td><%= product.category_name %></td>
        <td><%= link_to 'Edit', edit_product_path(product) %></td>
      </tr>
    <% end %>
  </tbody>
</table>

<br>

<%= link_to 'New Product', new_product_path %>

product.rb

class Product < ActiveRecord::Base
  belongs_to :category

  delegate :name, to: :category, allow_nil: true, prefix: true
end

products_controller.rb

class ProductsController < ApplicationController
  before_action :set_product, only: [:edit, :update, :destroy]

  def index
    @products = Product.all
  end

  def new
    @product = Product.new
  end

  def edit
  end

  def create
    @product = Product.new(product_params)

    if @product.save
      redirect_to products_url, notice: 'Product was successfully created.'
    else
      render :new
    end
  end

  def update
    if @product.update(product_params)
      redirect_to products_url, notice: 'Product was successfully updated.'
    else
      render :edit
    end
  end

  private

  def set_product
    @product = Product.find(params[:id])
  end

  def product_params
    params.require(:product).permit(:name, :description, :category_id)
  end

end

routes.rb

Rails.application.routes.draw do
  resources :categories
  resources :products, except: :destroy
end