Rails 5 ActiveRecord Cheat Sheet (DRAFT) by dwapi

class CreateProducts < ActiveRecord::Migration[5.0]
  def change
    create_table :products do |t|
      t.string :name
      t.text :description
 
      t.timestamps
    end
  end
end

class AddPartNumberToProducts < ActiveRecord::Migration[5.0]
  def change
    add_column :products, :part_number, :string
    add_index :products, :part_number
    add_reference :products, :user, foreign_key: true
    add_column :products, :price, :decimal, precision: 5, scale: 2
  end
end

class CreateJoinTableCustomerProduct < ActiveRecord::Migration[5.0]
  def change
    create_join_table :customers, :products do |t|
      # t.index [:customer_id, :product_id]
      # t.index [:product_id, :customer_id]
    end
  end
end

class ChangeProductsPrice < ActiveRecord::Migration[5.0]
  def up
    change_table :products do |t|
      t.change :price, :string
      rename_column :users, :email, :email_address
    end
  end
 
  def down
    change_table :products do |t|
      t.change :price, :integer
      rename_column :users, :email_address, :email
    end
  end
end

class User < ApplicationRecord
  validates :name, presence: true
  validates :name, length: { maximum: 20 }
  validates :password, length: { in: 6..20, message: "­%{v­alue} is not valid"  }
  validates :email, confir­mation: true # Adds tmp attr email_­con­fir­mation

  has_many :books, :dependent => :destroy
  valida­tes­_as­soc­iated :books #if has_many :books associ­ation
 
  before_save :ensure_login_has_a_value, if: :some_test?
  after_validation :set_location, on: [ :create, :update ]
  
  scope :published, -> { where(published: true) }
 
 
  private
    def ensure_login_has_a_value
      if login.nil?
        self.login = email unless email.blank?
      end
    end
end

Rails.application.routes.draw do

  root to: 'main#index'

  get "/login" => "sessions#new"
  get 'photos/:id', to: 'photos#show', defaults: { format: 'jpg' }
  
  post "/login" => "sessions#create"
  
  namespace :api do 
    resources :posts, only: [:index, :create, :destroy, :update] 
  end

  defaults format: :json do
    resources :photos
  end
  #Enable websocket requests
  mount ActionCable.server => '/cable'
end