Merge pull request #414 from raccoongang/fix/issue#412

fix(issue#412): Fixes issue #412 - AttributeError at /api/v0/courses/111/responses/ and /api/v0/courses/111/errors/

mysite/api/v0/views.py

@@ -1,5 +1,6 @@
 from rest_framework import viewsets
 from rest_framework.authentication import SessionAuthentication
+from rest_framework.generics import get_object_or_404
 
 from ..serializers import ResponseSerializer, ErrorSerializer
 from ..permissions import IsInstructor
@@ -15,9 +16,11 @@ class ResponseViewSet(viewsets.mixins.ListModelMixin, viewsets.GenericViewSet):
  queryset = Response.objects.filter(kind='orct', unitLesson__order__isnull=False)
  serializer_class = ResponseSerializer
 
+
  def get_queryset(self):
+ course = get_object_or_404(Course, id=self.kwargs.get('course_id'))
  self.check_object_permissions(
- self.request, Course.objects.filter(id=self.kwargs.get('course_id')).first()
+ self.request, course
  )
  queryset = super(ResponseViewSet, self).get_queryset()
  return queryset.filter(course__id=self.kwargs.get('course_id'))
@@ -33,8 +36,9 @@ class ErrorViewSet(viewsets.mixins.ListModelMixin, viewsets.GenericViewSet):
  serializer_class = ErrorSerializer
 
  def get_queryset(self):
+ course = get_object_or_404(Course, id=self.kwargs.get('course_id'))
  self.check_object_permissions(
- self.request, Course.objects.filter(id=self.kwargs.get('course_id')).first()
+ self.request, course
  )
  queryset = super(ErrorViewSet, self).get_queryset()
  return queryset.filter(response__course__id=self.kwargs.get('course_id'))