Fix: Optimizing activity discussion to use lighter Topic serializer and hide null values

courses_legacy/activities/serializers.py

 from rest_framework import serializers
 
 from discussion.models import Topic
-from discussion.serializers import TopicSerializer
+from discussion.serializers import BaseTopicSerializer
 
 from .models import Activity, Answer
 
@@ -24,4 +24,4 @@ class AnswerSerializer(serializers.ModelSerializer):
         except (Topic.DoesNotExist, AttributeError) as e:
             return
 
-        return TopicSerializer(instance=topic, **{'context': self.context}).data
+        return BaseTopicSerializer(instance=topic, **{'context': self.context}).data

courses_legacy/static/templates/activity_discussion.html

@@ -287,23 +287,23 @@
                 </tr>
             </thead>
             <tbody ng-repeat="course_class in classes_activities">
-                    <tr class="new" ng-repeat="answer in course_class.activity_answers">
-                        <td>
-                            <div class="user-icon">
-                              <img ng-src="{{ answer.topic.author.image || '/static/img/avatar-default.png'}}" alt="{{answer.topic.author.name}}">
+                <tr class="new" ng-repeat="answer in course_class.activity_answers" ng-hide="answer.topic === null">
+                    <td>
+                        <div class="user-icon">
+                            <img ng-src="{{ answer.topic.author.image || '/static/img/avatar-default.png'}}" alt="{{answer.topic.author.name}}">
 
-                            </div>
-                            <div class="info">
-                                <a ng-click="viewAnswer(answer.topic)"><span class="user-name">{{answer.topic.author.name}}</span></a>
-                            </div>
-                        </td>
-                        <td><b>{{course_class.name}}</b></td>
-                        <td>Última atividade <b>{{answer.topic.last_activity_at | date : 'dd/MM/yyyy' }}</b></td>
-                        <td>
-                            <!-- <span class="action liked">{{ activity.count_likes }} curtiram</span> -->
-                            <span class="action replies">{{ answer.topic.count_replies }} comentaram</span>
-                        </td>
-                    </tr>
+                        </div>
+                        <div class="info">
+                            <a ng-click="viewAnswer(answer.topic)"><span class="user-name">{{answer.topic.author.name}}</span></a>
+                        </div>
+                    </td>
+                    <td><b>{{course_class.name}}</b></td>
+                    <td>Últimadsadas atividade <b>{{answer.topic.last_activity_at | date : 'dd/MM/yyyy' }}</b></td>
+                    <td>
+                        <!-- <span class="action liked">{{ activity.count_likes }} curtiram</span> -->
+                        <span class="action replies">{{ answer.topic.count_replies }} comentaram</span>
+                    </td>
+                </tr>
             </tbody>
         </table>
     </div>