Update course metrics grades leaders API to allow filtering of users by groups

lms/djangoapps/api_manager/courses/views.py

@@ -1748,6 +1748,13 @@ class CoursesMetricsGradesLeadersList(SecureListAPIView):
         GET /api/courses/{course_id}/grades/leaders/
         """
         user_id = self.request.QUERY_PARAMS.get('user_id', None)
+        group_ids = self.request.QUERY_PARAMS.get('groups', None)
+        if group_ids:
+            try:
+                group_ids = map(int, group_ids.split(','))
+            except ValueError:
+                return Response({}, status.HTTP_400_BAD_REQUEST)
+
         count = self.request.QUERY_PARAMS.get('count', 3)
         data = {}
         course_avg = 0
@@ -1756,7 +1763,12 @@ class CoursesMetricsGradesLeadersList(SecureListAPIView):
         course_key = get_course_key(course_id)
         # Users having certain roles (such as an Observer) are excluded from aggregations
         exclude_users = get_aggregate_exclusion_user_ids(course_key)
-        leaderboard_data = StudentGradebook.generate_leaderboard(course_key, user_id=user_id, count=count, exclude_users=exclude_users)
+        leaderboard_data = StudentGradebook.generate_leaderboard(course_key,
+                                                                 user_id=user_id,
+                                                                 group_ids=group_ids,
+                                                                 count=count,
+                                                                 exclude_users=exclude_users)
+
         serializer = CourseLeadersSerializer(leaderboard_data['queryset'], many=True)
         data['leaders'] = serializer.data  # pylint: disable=E1101
         data['course_avg'] = leaderboard_data['course_avg']

lms/djangoapps/gradebook/models.py

@@ -82,9 +82,6 @@ class StudentGradebook(models.Model):
                         user__courseenrollment__course_id__exact=course_key,
                         user__in=enrolled_users_not_excluded)
 
-            if group_ids:
-                queryset.filter(user__groups__in=group_ids)
-
             gradebook_user_count = len(queryset)
 
             if gradebook_user_count:
@@ -100,6 +97,9 @@ class StudentGradebook(models.Model):
                     data['course_min'] = queryset.aggregate(Min('grade'))['grade__min']
                     data['course_count'] = queryset.aggregate(Count('grade'))['grade__count']
 
+                if group_ids:
+                    queryset = queryset.filter(user__groups__in=group_ids)
+
                 # Construct the leaderboard as a queryset
                 data['queryset'] = queryset.values(
                     'user__id',