Returning HTTP 200 if Course is Missing Submissions or Assignments

The templates will adjust accordingly to inform the user of the problem.

analytics_dashboard/courses/exceptions.py

@@ -24,3 +24,18 @@ class PermissionsRetrievalFailedError(PermissionsError):
     Raise if permissions retrieval fails (e.g. the backend is unreachable).
     """
     pass
+
+
+class NoAnswerSubmissionsError(Exception):
+    """
+    Raise if the course has no answer submissions.
+    """
+    course_id = None
+
+    def __init__(self, *args, **kwargs):
+        self.course_id = kwargs.pop('course_id')
+        super(NoAnswerSubmissionsError, self).__init__(*args, **kwargs)
+        self.message = 'No answers have been submitted for course {}.'.format(self.course_id)
+
+    def __str__(self):
+        return self.message

analytics_dashboard/courses/presenters/performance.py

@@ -11,6 +11,7 @@ import slumber
 
 import common
 from courses import utils
+from courses.exceptions import NoAnswerSubmissionsError
 from courses.presenters import BasePresenter
 from core.utils import sanitize_cache_key
 
@@ -212,7 +213,11 @@ class CoursePerformancePresenter(BasePresenter):
         if not problems:
             # Get the problems from the API
             logger.debug('Retrieving problem submissions for course: %s', self.course_id)
-            problems = self.client.courses(self.course_id).problems()
+
+            try:
+                problems = self.client.courses(self.course_id).problems()
+            except NotFoundError:
+                raise NoAnswerSubmissionsError(course_id=self.course_id)
 
             # Create a lookup table so that submission data can be quickly retrieved by downstream consumers.
             table = {}
@@ -258,17 +263,23 @@ class CoursePerformancePresenter(BasePresenter):
             'part_ids': []
         }
 
-        course_problems = self._course_problems()
+        try:
+            course_problems = self._course_problems()
+        except NoAnswerSubmissionsError as e:
+            logger.warning(e)
+            course_problems = {}
 
         for assignment in assignments:
             problems = assignment['problems']
 
             for index, problem in enumerate(problems):
                 data = course_problems.get(problem['id'], DEFAULT_DATA)
+
                 # map empty names to None so that the UI catches them and displays as '(empty)'
                 if len(problem['name']) < 1:
                     problem['name'] = None
                 data['index'] = index + 1
+
                 # not all problems have submissions
                 if len(data['part_ids']) > 0:
                     utils.sorting.natural_sort(data['part_ids'])
@@ -317,6 +328,7 @@ class CoursePerformancePresenter(BasePresenter):
                                assignment['assignment_type'].lower() == assignment_type]
 
             self._add_submissions_and_part_ids(assignments)
+
             for index, assignment in enumerate(assignments):
                 problems = assignment['problems']
                 total_submissions = sum(problem.get('total_submissions', 0) for problem in problems)

analytics_dashboard/courses/tests/factories.py

@@ -80,7 +80,7 @@ class CoursePerformanceDataFactory(object):
 
                 self._assignments.append(assignment)
 
-    def present_assignments(self):
+    def present_assignments(self, include_submissions=True):
         presented = []
 
         for assignment_index, assignment in enumerate(self._assignments):
@@ -95,22 +95,36 @@ class CoursePerformanceDataFactory(object):
                     correct_percent = 0
                 url_template = '/courses/{}/performance/graded_content/assignments/{}/problems/' \
                                '{}/parts/{}/answer_distribution/'
-                problems.append({
+
+                problem = {
                     'index': problem_index + 1,
-                    'total_submissions': problem_index,
-                    'correct_submissions': problem_index,
-                    'correct_percent': correct_percent,
-                    'incorrect_submissions': 0.0,
-                    'incorrect_percent': 0,
                     'id': _id,
                     'name': block['display_name'],
-                    'part_ids': [part_id],
-                    'url': urllib.quote(url_template.format(
-                        CoursePerformanceDataFactory.course_id, assignment['id'], _id, part_id))
-                })
+                    'total_submissions': 0,
+                    'correct_submissions': 0,
+                    'correct_percent': 0,
+                    'incorrect_submissions': 0,
+                    'incorrect_percent': 0,
+                    'part_ids': []
+                }
+
+                if include_submissions:
+                    problem.update({
+                        'part_ids': [part_id],
+                        'total_submissions': problem_index,
+                        'correct_submissions': problem_index,
+                        'correct_percent': correct_percent,
+                        'incorrect_submissions': 0,
+                        'incorrect_percent': 0,
+                        'url': urllib.quote(url_template.format(self.course_id, assignment['id'], _id, part_id)),
+                    })
+
+                problems.append(problem)
 
             num_problems = len(problems)
             url_template = '/courses/{}/performance/graded_content/assignments/{}/'
+            total_submissions = sum([problem['total_submissions'] for problem in problems])
+            correct_submissions = sum([problem['correct_submissions'] for problem in problems])
             presented_assignment = {
                 'index': assignment_index + 1,
                 'id': assignment['id'],
@@ -118,15 +132,16 @@ class CoursePerformanceDataFactory(object):
                 'assignment_type': assignment['format'],
                 'problems': problems,
                 'num_problems': num_problems,
-                'total_submissions': num_problems,
-                'correct_submissions': num_problems,
-                'correct_percent': 1.0,
+                'total_submissions': total_submissions,
+                'correct_submissions': correct_submissions,
+                'correct_percent': 0.0 if not total_submissions else correct_submissions / total_submissions,
                 'incorrect_submissions': 0,
-                'incorrect_percent': 0.0,
-                'url': urllib.quote(url_template.format(
-                    CoursePerformanceDataFactory.course_id, assignment['id']))
+                'incorrect_percent': 0.0
             }
 
+            if total_submissions > 0:
+                presented_assignment['url'] = urllib.quote(url_template.format(self.course_id, assignment['id']))
+
             presented.append(presented_assignment)
 
         return presented

analytics_dashboard/courses/tests/test_presenters.py

@@ -365,7 +365,6 @@ class CoursePerformancePresenterTests(TestCase):
                 self.assertEqual(self.presenter.last_updated, utils.CREATED_DATETIME)
 
                 # With an assignment type set, the presenter should return only the assignments of the specified type.
-                self.maxDiff = None
                 for assignment_type in self.factory.assignment_types:
                     cache.clear()
                     expected = [assignment for assignment in expected_assignments if

analytics_dashboard/courses/tests/test_views/test_performance.py

@@ -299,7 +299,8 @@ class CoursePerformanceGradedContentByTypeViewTests(CoursePerformanceViewTestMix
     @patch('courses.presenters.performance.CoursePerformancePresenter.assignments', Mock(return_value=[]))
     def test_missing_assignments(self):
         """
-        The view should return HTTP 404 if there are no assignments.
+        The view should return HTTP 200 if there are no assignments. The template will adjust to inform the user
+        of the issue.
 
         Assignments might be missing if the assignment type is invalid or the course is incomplete.
         """
@@ -310,7 +311,7 @@ class CoursePerformanceGradedContentByTypeViewTests(CoursePerformanceViewTestMix
         self.mock_course_detail(course_id)
 
         response = self.client.get(self.path(course_id=course_id, assignment_type='Invalid'))
-        self.assertEqual(response.status_code, 404)
+        self.assertEqual(response.status_code, 200)
 
 
 class CoursePerformanceAssignmentViewTests(CoursePerformanceViewTestMixin, TestCase):

analytics_dashboard/courses/views/performance.py

@@ -169,7 +169,6 @@ class PerformanceGradedContentByType(PerformanceTemplateView):
             # If there are no assignments, either the course is incomplete or the assignment type is invalid.
             # It is more likely that the assignment type is invalid, so return a 404.
             logger.info('No assignments of type %s were found for course %s', assignment_type, self.course_id)
-            raise Http404
 
         context.update({
             'page_data': self.get_page_data(context),