Merge pull request #135 from edx/dsjen/updgrade-drf

Update DRF to 3.4.6

analytics_data_api/v0/models.py

@@ -234,7 +234,7 @@ class Video(BaseVideo):
 
 class RosterUpdate(DocType):
 
-    date = Date()
+    date = Date(format=settings.DATE_FORMAT)
 
     # pylint: disable=old-style-class
     class Meta:
@@ -265,8 +265,8 @@ class RosterEntry(DocType):
     attempt_ratio_order = Integer()
     discussion_contributions = Integer()
     videos_watched = Integer()
-    enrollment_date = Date()
-    last_updated = Date()
+    enrollment_date = Date(format=settings.DATE_FORMAT)
+    last_updated = Date(format=settings.DATE_FORMAT)
 
     # pylint: disable=old-style-class
     class Meta:
@@ -460,7 +460,7 @@ class ModuleEngagement(models.Model):
 
     course_id = models.CharField(db_index=True, max_length=255)
     username = models.CharField(max_length=255)
-    date = models.DateTimeField()
+    date = models.DateField()
     # This will be one of "problem", "video" or "discussion"
     entity_type = models.CharField(max_length=255)
     # For problems this will be the usage key, for videos it will be the html encoded module ID,

analytics_data_api/v0/serializers.py

+from collections import OrderedDict
 from urlparse import urljoin
 from django.conf import settings
 from rest_framework import pagination, serializers
+from rest_framework.response import Response
 
 from analytics_data_api.constants import (
     engagement_events,
     enrollment_modes,
-    genders,
+    learner,
 )
 from analytics_data_api.v0 import models
 
@@ -23,7 +25,7 @@ class CourseActivityByWeekSerializer(serializers.ModelSerializer):
     particular record is likely to change unexpectedly so we avoid exposing it.
     """
 
-    activity_type = serializers.SerializerMethodField('get_activity_type')
+    activity_type = serializers.SerializerMethodField()
 
     def get_activity_type(self, obj):
         """
@@ -45,6 +47,7 @@ class ModelSerializerWithCreatedField(serializers.ModelSerializer):
     created = serializers.DateTimeField(format=settings.DATETIME_FORMAT)
 
 
+# pylint: disable=abstract-method
 class ProblemSerializer(serializers.Serializer):
     """
     Serializer for problems.
@@ -57,6 +60,7 @@ class ProblemSerializer(serializers.Serializer):
     created = serializers.DateTimeField(format=settings.DATETIME_FORMAT)
 
 
+# pylint: disable=abstract-method
 class ProblemsAndTagsSerializer(serializers.Serializer):
     """
     Serializer for problems and tags.
@@ -187,13 +191,7 @@ class SequentialOpenDistributionSerializer(ModelSerializerWithCreatedField):
         )
 
 
-class DefaultIfNoneMixin(object):
-
-    def default_if_none(self, value, default=0):
-        return value if value is not None else default
-
-
-class BaseCourseEnrollmentModelSerializer(DefaultIfNoneMixin, ModelSerializerWithCreatedField):
+class BaseCourseEnrollmentModelSerializer(ModelSerializerWithCreatedField):
     date = serializers.DateField(format=settings.DATE_FORMAT)
 
 
@@ -207,32 +205,35 @@ class CourseEnrollmentDailySerializer(BaseCourseEnrollmentModelSerializer):
 
 class CourseEnrollmentModeDailySerializer(BaseCourseEnrollmentModelSerializer):
     """ Representation of course enrollment, broken down by mode, for a single day and course. """
+    audit = serializers.SerializerMethodField()
+    credit = serializers.SerializerMethodField()
+    honor = serializers.SerializerMethodField()
+    professional = serializers.SerializerMethodField()
+    verified = serializers.SerializerMethodField()
 
-    def get_default_fields(self):
-        # pylint: disable=super-on-old-class
-        fields = super(CourseEnrollmentModeDailySerializer, self).get_default_fields()
+    def get_audit(self, obj):
+        return obj.get('audit', 0)
 
-        # Create a field for each enrollment mode
-        for mode in ENROLLMENT_MODES:
-            fields[mode] = serializers.IntegerField(required=True, default=0)
+    def get_honor(self, obj):
+        return obj.get('honor', 0)
 
-            # Create a transform method for each field
-            setattr(self, 'transform_%s' % mode, self._transform_mode)
+    def get_credit(self, obj):
+        return obj.get('credit', 0)
 
-        fields['cumulative_count'] = serializers.IntegerField(required=True, default=0)
+    def get_professional(self, obj):
+        return obj.get('professional', 0)
 
-        return fields
-
-    def _transform_mode(self, _obj, value):
-        return self.default_if_none(value, 0)
+    def get_verified(self, obj):
+        return obj.get('verified', 0)
 
     class Meta(object):
-        model = models.CourseEnrollmentDaily
+        model = models.CourseEnrollmentModeDaily
 
         # Declare the dynamically-created fields here as well so that they will be picked up by Swagger.
         fields = ['course_id', 'date', 'count', 'cumulative_count', 'created'] + ENROLLMENT_MODES
 
 
+# pylint: disable=abstract-method
 class CountrySerializer(serializers.Serializer):
     """
     Serialize country to an object with fields for the complete country name
@@ -256,21 +257,23 @@ class CourseEnrollmentByCountrySerializer(BaseCourseEnrollmentModelSerializer):
 
 
 class CourseEnrollmentByGenderSerializer(BaseCourseEnrollmentModelSerializer):
-    def get_default_fields(self):
-        # pylint: disable=super-on-old-class
-        fields = super(CourseEnrollmentByGenderSerializer, self).get_default_fields()
 
-        # Create a field for each gender
-        for gender in genders.ALL:
-            fields[gender] = serializers.IntegerField(required=True, default=0)
+    female = serializers.ReadOnlyField()
+    male = serializers.ReadOnlyField()
+    other = serializers.ReadOnlyField()
+    unknown = serializers.ReadOnlyField()
+
+    def get_female(self, obj):
+        return obj.get('female', None)
 
-            # Create a transform method for each field
-            setattr(self, 'transform_%s' % gender, self._transform_gender)
+    def get_male(self, obj):
+        return obj.get('male', None)
 
-        return fields
+    def get_other(self, obj):
+        return obj.get('other', None)
 
-    def _transform_gender(self, _obj, value):
-        return self.default_if_none(value, 0)
+    def get_unknown(self, obj):
+        return obj.get('unknown', None)
 
     class Meta(object):
         model = models.CourseEnrollmentByGender
@@ -329,28 +332,37 @@ class VideoTimelineSerializer(ModelSerializerWithCreatedField):
         )
 
 
+# pylint: disable=abstract-method
 class LastUpdatedSerializer(serializers.Serializer):
-    last_updated = serializers.DateField(source='date', format=settings.DATE_FORMAT)
+    last_updated = serializers.DateTimeField(source='date', format=settings.DATE_FORMAT)
 
 
-class LearnerSerializer(serializers.Serializer, DefaultIfNoneMixin):
-    username = serializers.CharField(source='username')
-    enrollment_mode = serializers.CharField(source='enrollment_mode')
-    name = serializers.CharField(source='name')
-    account_url = serializers.SerializerMethodField('get_account_url')
-    email = serializers.CharField(source='email')
-    segments = serializers.Field(source='segments')
-    engagements = serializers.SerializerMethodField('get_engagements')
-    enrollment_date = serializers.DateField(source='enrollment_date', format=settings.DATE_FORMAT)
-    cohort = serializers.CharField(source='cohort')
-
-    def transform_segments(self, _obj, value):
-        # returns null instead of empty strings
-        return value or []
+# pylint: disable=abstract-method
+class LearnerSerializer(serializers.Serializer):
+    username = serializers.CharField()
+    enrollment_mode = serializers.CharField()
+    name = serializers.CharField()
+    account_url = serializers.SerializerMethodField()
+    email = serializers.CharField()
+    segments = serializers.SerializerMethodField()
+    engagements = serializers.SerializerMethodField()
+    enrollment_date = serializers.DateTimeField(format=settings.DATE_FORMAT)
+    cohort = serializers.SerializerMethodField()
+
+    def get_segments(self, obj):
+        # using hasattr() instead because DocType.get() is overloaded and makes a request
+        if hasattr(obj, 'segments'):
+            # json parsing will fail unless in unicode
+            return [unicode(segment) for segment in obj.segments]
+        else:
+            return []
 
-    def transform_cohort(self, _obj, value):
-        # returns null instead of empty strings
-        return value or None
+    def get_cohort(self, obj):
+        # using hasattr() instead because DocType.get() is overloaded and makes a request
+        if hasattr(obj, 'cohort') and len(obj.cohort) > 0:
+            return obj.cohort
+        else:
+            return None
 
     def get_account_url(self, obj):
         if settings.LMS_USER_ACCOUNT_BASE_URL:
@@ -358,6 +370,9 @@ class LearnerSerializer(serializers.Serializer, DefaultIfNoneMixin):
         else:
             return None
 
+    def default_if_none(self, value, default=0):
+        return value if value is not None else default
+
     def get_engagements(self, obj):
         """
         Add the engagement totals.
@@ -376,52 +391,55 @@ class LearnerSerializer(serializers.Serializer, DefaultIfNoneMixin):
         return engagements
 
 
-class EdxPaginationSerializer(pagination.PaginationSerializer):
+class EdxPaginationSerializer(pagination.PageNumberPagination):
     """
     Adds values to the response according to edX REST API Conventions.
     """
-    count = serializers.Field(source='paginator.count')
-    num_pages = serializers.Field(source='paginator.num_pages')
-
-
-class ElasticsearchDSLSearchSerializer(EdxPaginationSerializer):
-    def __init__(self, *args, **kwargs):
-        """Make sure that the elasticsearch query is executed."""
-        # Because the elasticsearch-dsl search object has a different
-        # API from the queryset object that's expected by the django
-        # Paginator object, we have to manually execute the query.
-        # Note that the `kwargs['instance']` is the Page object, and
-        # `kwargs['instance'].object_list` is actually an
-        # elasticsearch-dsl search object.
-        kwargs['instance'].object_list = kwargs['instance'].object_list.execute()
-        super(ElasticsearchDSLSearchSerializer, self).__init__(*args, **kwargs)
-
-
-class EngagementDaySerializer(DefaultIfNoneMixin, serializers.Serializer):
+    page_size_query_param = 'page_size'
+    page_size = learner.LEARNER_API_DEFAULT_LIST_PAGE_SIZE
+    max_page_size = 100  # TODO -- tweak during load testing
+
+    def get_paginated_response(self, data):
+        # The output is more readable with num_pages included not at the end, but
+        # inefficient to insert into an OrderedDict, so the response is copied from
+        # rest_framework.pagination with the addition of "num_pages".
+        return Response(OrderedDict([
+            ('count', self.page.paginator.count),
+            ('num_pages', self.page.paginator.num_pages),
+            ('next', self.get_next_link()),
+            ('previous', self.get_previous_link()),
+            ('results', data)
+        ]))
+
+
+# pylint: disable=abstract-method
+class EngagementDaySerializer(serializers.Serializer):
     date = serializers.DateField(format=settings.DATE_FORMAT)
-    problems_attempted = serializers.IntegerField(required=True, default=0)
-    problems_completed = serializers.IntegerField(required=True, default=0)
-    discussion_contributions = serializers.IntegerField(required=True, default=0)
-    videos_viewed = serializers.IntegerField(required=True, default=0)
+    problems_attempted = serializers.SerializerMethodField()
+    problems_completed = serializers.SerializerMethodField()
+    discussion_contributions = serializers.SerializerMethodField()
+    videos_viewed = serializers.SerializerMethodField()
 
-    def transform_problems_attempted(self, _obj, value):
-        return self.default_if_none(value, 0)
+    def get_problems_attempted(self, obj):
+        return obj.get('problems_attempted', 0)
 
-    def transform_problems_completed(self, _obj, value):
-        return self.default_if_none(value, 0)
+    def get_problems_completed(self, obj):
+        return obj.get('problems_completed', 0)
 
-    def transform_discussion_contributions(self, _obj, value):
-        return self.default_if_none(value, 0)
+    def get_discussion_contributions(self, obj):
+        return obj.get('discussion_contributions', 0)
 
-    def transform_videos_viewed(self, _obj, value):
-        return self.default_if_none(value, 0)
+    def get_videos_viewed(self, obj):
+        return obj.get('videos_viewed', 0)
 
 
+# pylint: disable=abstract-method
 class DateRangeSerializer(serializers.Serializer):
     start = serializers.DateTimeField(source='start_date', format=settings.DATE_FORMAT)
     end = serializers.DateTimeField(source='end_date', format=settings.DATE_FORMAT)
 
 
+# pylint: disable=abstract-method
 class EnagementRangeMetricSerializer(serializers.Serializer):
     """
     Serializes ModuleEngagementMetricRanges ('bottom', 'average', and 'top') into
@@ -429,9 +447,9 @@ class EnagementRangeMetricSerializer(serializers.Serializer):
     represented as arrays. If any one of the ranges is not defined, it is not
     included in the serialized output.
     """
-    class_rank_bottom = serializers.SerializerMethodField('get_class_rank_bottom')
-    class_rank_average = serializers.SerializerMethodField('get_class_rank_average')
-    class_rank_top = serializers.SerializerMethodField('get_class_rank_top')
+    class_rank_bottom = serializers.SerializerMethodField()
+    class_rank_average = serializers.SerializerMethodField()
+    class_rank_top = serializers.SerializerMethodField()
 
     def get_class_rank_average(self, obj):
         return self._transform_range(obj['average'])
@@ -446,11 +464,12 @@ class EnagementRangeMetricSerializer(serializers.Serializer):
         return [metric_range.low_value, metric_range.high_value] if metric_range else None
 
 
+# pylint: disable=abstract-method
 class CourseLearnerMetadataSerializer(serializers.Serializer):
-    enrollment_modes = serializers.Field(source='es_data.enrollment_modes')
-    segments = serializers.Field(source='es_data.segments')
-    cohorts = serializers.Field(source='es_data.cohorts')
-    engagement_ranges = serializers.SerializerMethodField('get_engagement_ranges')
+    enrollment_modes = serializers.ReadOnlyField(source='es_data.enrollment_modes')
+    segments = serializers.ReadOnlyField(source='es_data.segments')
+    cohorts = serializers.ReadOnlyField(source='es_data.cohorts')
+    engagement_ranges = serializers.SerializerMethodField()
 
     def get_engagement_ranges(self, obj):
         query_set = obj['engagement_ranges']

analytics_data_api/v0/tests/views/test_courses.py

@@ -210,10 +210,11 @@ class CourseActivityLastWeekTest(DemoCourseMixin, TestCaseWithAuthentication):
 
     @staticmethod
     def get_activity_record(**kwargs):
+        datetime_format = "%Y-%m-%dT%H:%M:%SZ"
         default = {
             'course_id': DEMO_COURSE_ID,
-            'interval_start': datetime.datetime(2014, 1, 1, 0, 0, tzinfo=pytz.utc),
-            'interval_end': datetime.datetime(2014, 1, 8, 0, 0, tzinfo=pytz.utc),
+            'interval_start': datetime.datetime(2014, 1, 1, 0, 0, tzinfo=pytz.utc).strftime(datetime_format),
+            'interval_end': datetime.datetime(2014, 1, 8, 0, 0, tzinfo=pytz.utc).strftime(datetime_format),
             'activity_type': 'any',
             'count': 300,
         }
@@ -339,6 +340,9 @@ class CourseEnrollmentByGenderViewTests(CourseEnrollmentViewTestCaseMixin, Defau
         super(CourseEnrollmentByGenderViewTests, self).setUp()
         self.generate_data()
 
+    def tearDown(self):
+        self.destroy_data()
+
     def serialize_enrollment(self, enrollment):
         return {
             'created': enrollment.created.strftime(settings.DATETIME_FORMAT),
@@ -606,8 +610,8 @@ class CourseProblemsListViewTests(DemoCourseMixin, TestCaseWithAuthentication):
 
         # Create multiple objects here to test the grouping. Add a model with a different module_id to break up the
         # natural order and ensure the view properly sorts the objects before grouping.
-        module_id = 'i4x://test/problem/1'
-        alt_module_id = 'i4x://test/problem/2'
+        module_id = u'i4x://test/problem/1'
+        alt_module_id = u'i4x://test/problem/2'
         created = datetime.datetime.utcnow()
         alt_created = created + datetime.timedelta(seconds=2)
         date_time_format = '%Y-%m-%d %H:%M:%S'
@@ -624,21 +628,21 @@ class CourseProblemsListViewTests(DemoCourseMixin, TestCaseWithAuthentication):
                 'module_id': module_id,
                 'total_submissions': 150,
                 'correct_submissions': 50,
-                'part_ids': [o1.part_id, o3.part_id],
+                'part_ids': unicode([o1.part_id, o3.part_id]),
                 'created': alt_created.strftime(settings.DATETIME_FORMAT)
             },
             {
                 'module_id': alt_module_id,
                 'total_submissions': 100,
                 'correct_submissions': 100,
-                'part_ids': [o2.part_id],
-                'created': created.strftime(settings.DATETIME_FORMAT)
+                'part_ids': unicode([o2.part_id]),
+                'created': unicode(created.strftime(settings.DATETIME_FORMAT))
             }
         ]
 
         response = self._get_data(self.course_id)
         self.assertEquals(response.status_code, 200)
-        self.assertListEqual(response.data, expected)
+        self.assertListEqual([dict(d) for d in response.data], expected)
 
     def test_get_404(self):
         """
@@ -669,8 +673,8 @@ class CourseProblemsAndTagsListViewTests(DemoCourseMixin, TestCaseWithAuthentica
 
         # Create multiple objects here to test the grouping. Add a model with a different module_id to break up the
         # natural order and ensure the view properly sorts the objects before grouping.
-        module_id = 'i4x://test/problem/1'
-        alt_module_id = 'i4x://test/problem/2'
+        module_id = u'i4x://test/problem/1'
+        alt_module_id = u'i4x://test/problem/2'
 
         tags = {
             'difficulty': ['Easy', 'Medium', 'Hard'],
@@ -695,26 +699,26 @@ class CourseProblemsAndTagsListViewTests(DemoCourseMixin, TestCaseWithAuthentica
                 'module_id': module_id,
                 'total_submissions': 11,
                 'correct_submissions': 4,
-                'tags': {
-                    'difficulty': 'Easy',
-                    'learning_outcome': 'Learned a few things',
-                },
+                'tags': unicode({
+                    u'difficulty': u'Easy',
+                    u'learning_outcome': u'Learned a few things',
+                }),
                 'created': alt_created.strftime(settings.DATETIME_FORMAT)
             },
             {
                 'module_id': alt_module_id,
                 'total_submissions': 4,
                 'correct_submissions': 0,
-                'tags': {
-                    'learning_outcome': 'Learned everything',
-                },
+                'tags': unicode({
+                    u'learning_outcome': u'Learned everything',
+                }),
                 'created': created.strftime(settings.DATETIME_FORMAT)
             }
         ]
 
         response = self._get_data(self.course_id)
         self.assertEquals(response.status_code, 200)
-        self.assertListEqual(sorted(response.data), sorted(expected))
+        self.assertListEqual(sorted([dict(d) for d in response.data]), sorted(expected))
 
     def test_get_404(self):
         """

analytics_data_api/v0/tests/views/test_learners.py

@@ -205,8 +205,7 @@ class LearnerListTests(LearnerAPITestMixin, VerifyCourseIdMixin, TestCaseWithAut
         returned.
         """
         self.assertEqual(response.status_code, 200)
-        payload = json.loads(response.content)
-        returned_learners = payload['results']
+        returned_learners = json.loads(response.content)['results']
         if expected_learners is None:
             self.assertEqual(returned_learners, list())
         else:

analytics_data_api/v0/views/__init__.py

@@ -12,7 +12,7 @@ class CourseViewMixin(object):
     course_id = None
 
     def get(self, request, *args, **kwargs):
-        self.course_id = self.kwargs.get('course_id', request.QUERY_PARAMS.get('course_id', None))
+        self.course_id = self.kwargs.get('course_id', request.query_params.get('course_id', None))
 
         if not self.course_id:
             raise CourseNotSpecifiedError()

analytics_data_api/v0/views/courses.py

@@ -15,6 +15,8 @@ from analytics_data_api.constants import enrollment_modes
 from analytics_data_api.utils import dictfetchall
 from analytics_data_api.v0 import models, serializers
 
+from analytics_data_api.v0.views.utils import raise_404_if_none
+
 
 class BaseCourseView(generics.ListAPIView):
     start_date = None
@@ -25,8 +27,8 @@ class BaseCourseView(generics.ListAPIView):
 
     def get(self, request, *args, **kwargs):
         self.course_id = self.kwargs.get('course_id')
-        start_date = request.QUERY_PARAMS.get('start_date')
-        end_date = request.QUERY_PARAMS.get('end_date')
+        start_date = request.query_params.get('start_date')
+        end_date = request.query_params.get('end_date')
         timezone = utc
 
         self.start_date = self.parse_date(start_date, timezone)
@@ -46,6 +48,7 @@ class BaseCourseView(generics.ListAPIView):
     def apply_date_filtering(self, queryset):
         raise NotImplementedError
 
+    @raise_404_if_none
     def get_queryset(self):
         queryset = self.model.objects.filter(course_id=self.course_id)
         queryset = self.apply_date_filtering(queryset)
@@ -232,14 +235,14 @@ class CourseActivityMostRecentWeekView(generics.RetrieveAPIView):
         """ Retrieve the activity type from the query string. """
 
         # Support the old label param
-        activity_type = self.request.QUERY_PARAMS.get('label', None)
+        activity_type = self.request.query_params.get('label', None)
 
-        activity_type = activity_type or self.request.QUERY_PARAMS.get('activity_type', self.DEFAULT_ACTIVITY_TYPE)
+        activity_type = activity_type or self.request.query_params.get('activity_type', self.DEFAULT_ACTIVITY_TYPE)
         activity_type = self._format_activity_type(activity_type)
 
         return activity_type
 
-    def get_object(self, queryset=None):
+    def get_object(self):
         """Select the activity report for the given course and activity type."""
 
         warnings.warn('CourseActivityMostRecentWeekView has been deprecated! Use CourseActivityWeeklyView instead.',
@@ -400,7 +403,11 @@ class CourseEnrollmentByGenderView(BaseCourseEnrollmentView):
             item = {
                 u'course_id': key[0],
                 u'date': key[1],
-                u'created': None
+                u'created': None,
+                u'male': 0,
+                u'female': 0,
+                u'other': 0,
+                u'unknown': 0
             }
 
             for enrollment in group:
@@ -633,6 +640,7 @@ class ProblemsListView(BaseCourseView):
     serializer_class = serializers.ProblemSerializer
     allow_empty = False
 
+    @raise_404_if_none
     def get_queryset(self):
         # last_response_count is the number of submissions for the problem part and must
         # be divided by the number of problem parts to get the problem submission rather
@@ -709,6 +717,7 @@ class ProblemsAndTagsListView(BaseCourseView):
     allow_empty = False
     model = models.ProblemsAndTags
 
+    @raise_404_if_none
     def get_queryset(self):
         queryset = self.model.objects.filter(course_id=self.course_id)
         items = queryset.all()

analytics_data_api/v0/views/learners.py

@@ -5,9 +5,6 @@ import logging
 
 from rest_framework import generics, status
 
-from analytics_data_api.constants import (
-    learner
-)
 from analytics_data_api.v0.exceptions import (
     LearnerEngagementTimelineNotFoundError,
     LearnerNotFoundError,
@@ -21,7 +18,7 @@ from analytics_data_api.v0.models import (
 )
 from analytics_data_api.v0.serializers import (
     CourseLearnerMetadataSerializer,
-    ElasticsearchDSLSearchSerializer,
+    EdxPaginationSerializer,
     EngagementDaySerializer,
     LastUpdatedSerializer,
     LearnerSerializer,
@@ -106,7 +103,7 @@ class LearnerView(LastUpdateMixin, CourseViewMixin, generics.RetrieveAPIView):
     def get_queryset(self):
         return RosterEntry.get_course_user(self.course_id, self.username)
 
-    def get_object(self, queryset=None):
+    def get_object(self):
         queryset = self.get_queryset()
         if len(queryset) == 1:
             return queryset[0]
@@ -187,14 +184,12 @@ class LearnerListView(LastUpdateMixin, CourseViewMixin, generics.ListAPIView):
 
     """
     serializer_class = LearnerSerializer
-    pagination_serializer_class = ElasticsearchDSLSearchSerializer
-    paginate_by_param = 'page_size'
-    paginate_by = learner.LEARNER_API_DEFAULT_LIST_PAGE_SIZE
+    pagination_class = EdxPaginationSerializer
     max_paginate_by = 100  # TODO -- tweak during load testing
 
     def _validate_query_params(self):
         """Validates various querystring parameters."""
-        query_params = self.request.QUERY_PARAMS
+        query_params = self.request.query_params
         page = query_params.get('page')
         if page:
             try:
@@ -222,8 +217,9 @@ class LearnerListView(LastUpdateMixin, CourseViewMixin, generics.ListAPIView):
         """
         response = super(LearnerListView, self).list(request, args, kwargs)
         last_updated = self.get_last_updated()
-        for result in response.data['results']:
-            result.update(last_updated)
+        if response.data['results'] is not None:
+            for result in response.data['results']:
+                result.update(last_updated)
         return response
 
     def get_queryset(self):
@@ -232,7 +228,7 @@ class LearnerListView(LastUpdateMixin, CourseViewMixin, generics.ListAPIView):
         as a an array of dicts with fields "learner" and "last_updated".
         """
         self._validate_query_params()
-        query_params = self.request.QUERY_PARAMS
+        query_params = self.request.query_params
 
         order_by = query_params.get('order_by')
         sort_order = query_params.get('sort_order')
@@ -366,7 +362,7 @@ class CourseLearnerMetadata(CourseViewMixin, generics.RetrieveAPIView):
     """
     serializer_class = CourseLearnerMetadataSerializer
 
-    def get_object(self, queryset=None):
+    def get_object(self):
         # Because we're serializing data from both Elasticsearch and MySQL into
         # the same JSON object, we have to pass both sources of data in a dict
         # to our custom course metadata serializer.

analytics_data_api/v0/views/problems.py

@@ -22,6 +22,8 @@ from analytics_data_api.v0.serializers import (
 )
 from analytics_data_api.utils import matching_tuple
 
+from analytics_data_api.v0.views.utils import raise_404_if_none
+
 
 class ProblemResponseAnswerDistributionView(generics.ListAPIView):
     """
@@ -98,6 +100,7 @@ class ProblemResponseAnswerDistributionView(generics.ListAPIView):
 
         return consolidated_answers
 
+    @raise_404_if_none
     def get_queryset(self):
         """Select all the answer distribution response having to do with this usage of the problem."""
         problem_id = self.kwargs.get('problem_id')
@@ -142,6 +145,7 @@ class GradeDistributionView(generics.ListAPIView):
     serializer_class = GradeDistributionSerializer
     allow_empty = False
 
+    @raise_404_if_none
     def get_queryset(self):
         """Select all grade distributions for a particular module"""
         problem_id = self.kwargs.get('problem_id')
@@ -170,6 +174,7 @@ class SequentialOpenDistributionView(generics.ListAPIView):
     serializer_class = SequentialOpenDistributionSerializer
     allow_empty = False
 
+    @raise_404_if_none
     def get_queryset(self):
         """Select the view count for a specific module"""
         module_id = self.kwargs.get('module_id')

analytics_data_api/v0/views/utils.py

 """Utilities for view-level API logic."""
+from django.http import Http404
 
 
 def split_query_argument(argument):
@@ -10,3 +11,16 @@ def split_query_argument(argument):
         return argument.split(',')
     else:
         return None
+
+
+def raise_404_if_none(func):
+    """
+    Decorator for raiseing Http404 if function evaulation is falsey (e.g. empty queryset).
+    """
+    def func_wrapper(self):
+        queryset = func(self)
+        if queryset:
+            return queryset
+        else:
+            raise Http404
+    return func_wrapper

analytics_data_api/v0/views/videos.py

@@ -7,6 +7,8 @@ from rest_framework import generics
 from analytics_data_api.v0.models import VideoTimeline
 from analytics_data_api.v0.serializers import VideoTimelineSerializer
 
+from analytics_data_api.v0.views.utils import raise_404_if_none
+
 
 class VideoTimelineView(generics.ListAPIView):
     """
@@ -30,6 +32,7 @@ class VideoTimelineView(generics.ListAPIView):
     serializer_class = VideoTimelineSerializer
     allow_empty = False
 
+    @raise_404_if_none
     def get_queryset(self):
         """Select the view count for a specific module"""
         video_id = self.kwargs.get('video_id')

requirements/base.txt

 boto==2.22.1                        # MIT
 Django==1.8.14 						# BSD License
 django-model-utils==2.2 			# BSD
-djangorestframework==2.4.4			# BSD
+djangorestframework==3.4.6			# BSD
 django-rest-swagger==0.2.8  		# BSD
 djangorestframework-csv==1.3.3		# BSD
 django-countries==3.2               # MIT