Allow plugins to build topic lists

lib/topic_list_responder.rb

@@ -0,0 +1,24 @@
+# Helps us respond with a topic list from a controller
+module TopicListResponder
+
+  def respond_with_list(list)
+    discourse_expires_in 1.minute
+
+    list.draft_key = Draft::NEW_TOPIC
+    list.draft_sequence = DraftSequence.current(current_user, Draft::NEW_TOPIC)
+    list.draft = Draft.get(current_user, list.draft_key, list.draft_sequence) if current_user
+
+    respond_to do |format|
+      format.html do
+        @list = list
+        store_preloaded(list.preload_key, MultiJson.dump(TopicListSerializer.new(list, scope: guardian)))
+        render 'list'
+      end
+      format.json do
+        render_serialized(list, TopicListSerializer)
+      end
+    end
+  end
+
+end
+