Fixing bug

app/models/topic.rb

 class Topic < ActiveRecord::Base
   has_and_belongs_to_many :learning_objects
 
-  has_many :topic_relationships, foreign_key: "parent_id", dependent: :destroy, autosave: true
-  has_many :subtopics, through: :topic_relationships, source: :child, autosave: true
+  has_many :topic_relationships, foreign_key: "parent_id", dependent: :destroy
+  has_many :subtopics, through: :topic_relationships, source: :child
 
   has_many :topic_highlights, dependent: :destroy
 

app/services/topics_importer.rb

@@ -4,38 +4,63 @@ class TopicsImporter
   def initialize items
     @items = items
     @@topics = {}
+    @@topics_relations = []
   end
 
   def import
 
-    topics = []
+    relations = []
 
     @items.each do |learning_object|
+
       lo_topics = parse_topics ( learning_object.get_metadata_values_of "dc.subject.category" )
+
       lo_topics.each_with_index do |topic_name, i|
 
         next if topic_exists? topic_name
 
         topic = Topic.where(name: topic_name).new
-
         topic.learning_objects << learning_object
-
-        create_relations(@@topics[lo_topics[i - 1]], topic) unless i == 0
-
+        create_relations(lo_topics[i - 1], topic_name) unless i == 0
         @@topics[topic_name] = topic
 
-        end
       end
+      separate_relations()
+    end
 
-    Topic.import @@topics.values, recursive: true
+    Topic.import @@topics.values
+    import_topics_relations()
 
   end
 
 
   private
 
-  def create_relations parent_topic, topic
-    parent_topic.subtopics << topic
+  def create_relations parent_name, child_name
+    @@topics_relations.push(parent_name)
+    @@topics_relations.push(child_name)
+  end
+
+  def separate_relations
+    @@topics_relations.push nil
+  end
+
+  def import_topics_relations
+
+    relations = []
+
+    @@topics_relations.each_with_index do |relation, i|
+      unless  relation.nil? || @@topics_relations[i - 1].nil?
+        parent_id =  Topic.find_by_name(@@topics_relations[i - 1]).id
+        child_id = Topic.find_by_name(relation).id
+        unless TopicRelationship.exists?(parent_id: parent_id, child_id: child_id) || i == 0
+          relations.push TopicRelationship.where(parent_id: parent_id, child_id: child_id ).new
+        end
+      end
+    end
+
+    TopicRelationship.import relations
+
   end
 
   def parse_topics values
@@ -44,12 +69,11 @@ class TopicsImporter
     values.each do |value|
       topics = value.split('::')
     end
-    topics
+    topics.map{|topic| topic.strip}
   end
 
   def topic_exists? (topic_name)
     Topic.exists? name: topic_name || !@@topics[topic_name].nil?
   end
 
-
 end