Associate a user to his playlists

app/controllers/playlists_controller.rb

@@ -8,7 +8,7 @@ class PlaylistsController < ApplicationController
   end
 
   def create
-    @playlist = Playlist.new(:name => params[:playlist][:name])
+    @playlist = current_user.playlists.build(params[:playlist])
     if @playlist.save
       redirect_to :action => 'index'
     else

app/models/playlist.rb

@@ -1,3 +1,6 @@
 class Playlist < ActiveRecord::Base
+  belongs_to :user
+
+  validates_presence_of :user_id
   validates_presence_of :name
 end

app/models/user.rb

@@ -6,6 +6,8 @@ class User < ActiveRecord::Base
   attr_reader :password
   attr_accessible :email, :password, :password_confirmation
 
+  has_many :playlists
+
   validates_presence_of :email, :password_hash
   validates_confirmation_of :password