refactoring learning object attachments

app/models/learning_object.rb

@@ -9,24 +9,11 @@ class LearningObject < ActiveRecord::Base
   has_many :collections, through: :collection_items
 
   has_many :complaints
+  has_many :attachments, class_name: 'LearningObject::Attachment'
 
   belongs_to :publisher, polymorphic: true
 
   def categories
     get_metadata_value_of 'dc.subject.category'
   end
-
-  def liked?(user)
-    return false if likes.where(user: user).blank?
-
-    true
-  end
-
-  def like(user)
-    Like.create(user: user, likeable: self)
-  end
-
-  def dislike(user)
-    Like.where(user: user, likeable: self).destroy_all
-  end
 end

app/models/learning_object/attachment.rb

-class LearningObject::Attachment
-  include ActiveModel::Model
-
-  #this attributes mirror Dspace bitstream values
-  attr_accessor :id, :name, :link, :retrieve_link, :description, :format, :mime_type, :size, :bundle_name
+class LearningObject::Attachment < ActiveRecord::Base
+  belongs_to :learning_object
 end

db/migrate/20160201135415_create_learning_object_attachments.rb

+class CreateLearningObjectAttachments < ActiveRecord::Migration
+  def change
+    create_table :learning_object_attachments do |t|
+      t.string :name
+      t.string :link
+      t.string :retrieve_link
+      t.text :description
+      t.string :format
+      t.string :mime_type
+      t.integer :size
+      t.string :bundle_name
+      t.belongs_to :learning_object, index: true
+
+      t.timestamps null: false
+    end
+    add_foreign_key :learning_object_attachments, :learning_objects
+  end
+end

db/migrate/20160201140345_remove_bitstreams_column_from_learning_objects.rb

+class RemoveBitstreamsColumnFromLearningObjects < ActiveRecord::Migration
+  def change
+    remove_column :learning_objects, :bitstreams
+  end
+end