Product calories: DB migration + Model update + attribute permit

app/controllers/products_controller.rb

@@ -57,6 +57,6 @@ class ProductsController < ApplicationController
   private
 
     def product_params
-      params.require(:product).permit(:name, :price, :avatar, :category, :stock)
+      params.require(:product).permit(:name, :price, :avatar, :category, :stock, :calories)
     end
 end

app/models/product.rb

@@ -13,6 +13,7 @@
 #  avatar_updated_at   :datetime
 #  category            :integer          default("0")
 #  stock               :integer          default("0"), not null
+#  calories            :integer          default("0"), not null // expressed in kcal
 #
 
 class Product < ActiveRecord::Base
@@ -24,6 +25,7 @@ class Product < ActiveRecord::Base
   validates :name, presence: true
   validates :price_cents, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
   validates :stock, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
+  validates :calories, numericality: { only_integer: true, :allow_nil => true, greater_than_or_equal_to: 0 }
   validates_attachment :avatar,
     presence: true,
     content_type: { content_type: ["image/jpeg", "image/gif", "image/png"] }

db/migrate/20150707162949_add_calories_to_products.rb

@@ -0,0 +1,5 @@
+class AddCaloriesToProducts < ActiveRecord::Migration
+  def change
+    add_column :products, :calories, :int
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20150630183223) do
+ActiveRecord::Schema.define(version: 20150707162949) do
 
   create_table "order_items", force: :cascade do |t|
     t.integer "order_id"
@@ -41,6 +41,7 @@ ActiveRecord::Schema.define(version: 20150630183223) do
     t.datetime "avatar_updated_at"
     t.integer  "category",            default: 0
     t.integer  "stock",               default: 0, null: false
+    t.integer  "calories"
   end
 
   create_table "users", force: :cascade do |t|