added tags schema and model

app/models/recipe.rb

@@ -4,6 +4,8 @@ class Recipe < ApplicationRecord
   has_many :recipe_steps, -> { order :sort_order }, inverse_of: :recipe, dependent: :destroy
   belongs_to :user
 
+  has_and_belongs_to_many :tags
+
   scope :undeleted, -> { where('deleted <> ? OR deleted IS NULL', true) }
   scope :not_log, -> { where('is_log <> ? OR is_log IS NULL', true) }
   scope :active, -> { undeleted.not_log }

app/models/tag.rb

@@ -0,0 +1,5 @@
+class Tag < ApplicationRecord
+
+  validates :name, presence: true, length: {maximum: 250}, uniqueness: { case_sensitive: false }
+
+end

db/migrate/20161014173138_create_tags.rb

@@ -0,0 +1,14 @@
+class CreateTags < ActiveRecord::Migration[5.0]
+  def change
+    create_table :tags do |t|
+      t.string :name, index: {unique: true}
+
+      t.timestamps
+    end
+
+    create_table :recipes_tags, id: false do |t|
+      t.integer :recipe_id, index: true
+      t.integer :tag_id, index: true
+    end
+  end
+end

spec/factories/tags.rb

@@ -0,0 +1,5 @@
+FactoryGirl.define do
+  factory :tag do
+    name "MyString"
+  end
+end

spec/models/tag_spec.rb

@@ -0,0 +1,5 @@
+require 'rails_helper'
+
+RSpec.describe Tag, type: :model do
+  pending "add some examples to (or delete) #{__FILE__}"
+end