Make GradingServices always return dictionaries, rather than sometimes returning strings

common/lib/xmodule/xmodule/open_ended_grading_classes/grading_service_module.py

@@ -132,30 +132,25 @@ class GradingService(object):
 
     def _render_rubric(self, response, view_only=False):
         """
-        Given an HTTP Response with the key 'rubric', render out the html
+        Given an HTTP Response json with the key 'rubric', render out the html
         required to display the rubric and put it back into the response
 
         returns the updated response as a dictionary that can be serialized later
 
         """
         try:
-            response_json = json.loads(response)
-        except:
-            response_json = response
-
-        try:
-            if 'rubric' in response_json:
-                rubric = response_json['rubric']
+            if 'rubric' in response:
+                rubric = response['rubric']
                 rubric_renderer = CombinedOpenEndedRubric(self.system, view_only)
                 rubric_dict = rubric_renderer.render_rubric(rubric)
                 success = rubric_dict['success']
                 rubric_html = rubric_dict['html']
-                response_json['rubric'] = rubric_html
-            return response_json
+                response['rubric'] = rubric_html
+            return response
         # if we can't parse the rubric into HTML,
         except (etree.XMLSyntaxError, RubricParsingError):
             #This is a dev_facing_error
-            log.exception("Cannot parse rubric string. Raw string: {0}".format(rubric))
+            log.exception("Cannot parse rubric string. Raw string: {0}".format(response['rubric']))
             return {'success': False,
                     'error': 'Error displaying submission'}
         except ValueError:

common/lib/xmodule/xmodule/open_ended_grading_classes/peer_grading_service.py

@@ -29,7 +29,7 @@ class PeerGradingService(GradingService):
     def get_data_for_location(self, problem_location, student_id):
         params = {'location': problem_location, 'student_id': student_id}
         response = self.get(self.get_data_for_location_url, params)
-        return self.try_to_decode(response)
+        return response.json()
 
     def get_next_submission(self, problem_location, grader_id):
         response = self.get(
@@ -39,43 +39,36 @@ class PeerGradingService(GradingService):
                 'grader_id': grader_id
             }
         )
-        return self.try_to_decode(self._render_rubric(response))
+        return self._render_rubric(response.json())
 
     def save_grade(self, **kwargs):
         data = kwargs
         data.update({'rubric_scores_complete': True})
-        return self.try_to_decode(self.post(self.save_grade_url, data))
+        return self.post(self.save_grade_url, data).json()
 
     def is_student_calibrated(self, problem_location, grader_id):
         params = {'problem_id': problem_location, 'student_id': grader_id}
-        return self.try_to_decode(self.get(self.is_student_calibrated_url, params))
+        return self.get(self.is_student_calibrated_url, params).json()
 
     def show_calibration_essay(self, problem_location, grader_id):
         params = {'problem_id': problem_location, 'student_id': grader_id}
         response = self.get(self.show_calibration_essay_url, params)
-        return self.try_to_decode(self._render_rubric(response))
+        return self._render_rubric(response.json())
 
     def save_calibration_essay(self, **kwargs):
         data = kwargs
         data.update({'rubric_scores_complete': True})
-        return self.try_to_decode(self.post(self.save_calibration_essay_url, data))
+        return self.post(self.save_calibration_essay_url, data).json()
 
     def get_problem_list(self, course_id, grader_id):
         params = {'course_id': course_id, 'student_id': grader_id}
         response = self.get(self.get_problem_list_url, params)
-        return self.try_to_decode(response)
+        return response.json()
 
     def get_notifications(self, course_id, grader_id):
         params = {'course_id': course_id, 'student_id': grader_id}
         response = self.get(self.get_notifications_url, params)
-        return self.try_to_decode(response)
-
-    def try_to_decode(self, text):
-        try:
-            text = json.loads(text)
-        except:
-            pass
-        return text
+        return response.json()
 
 
 """

common/lib/xmodule/xmodule/peer_grading_module.py

@@ -539,8 +539,7 @@ class PeerGradingModule(PeerGradingFields, XModule):
         error_text = ""
         problem_list = []
         try:
-            problem_list_json = self.peer_gs.get_problem_list(self.course_id, self.system.anonymous_student_id)
-            problem_list_dict = problem_list_json
+            problem_list_dict = self.peer_gs.get_problem_list(self.course_id, self.system.anonymous_student_id)
             success = problem_list_dict['success']
             if 'error' in problem_list_dict:
                 error_text = problem_list_dict['error']

lms/djangoapps/open_ended_grading/staff_grading_service.py

@@ -44,7 +44,7 @@ class MockStaffGradingService(object):
 
     def get_next(self, course_id, location, grader_id):
         self.cnt += 1
-        return json.dumps({'success': True,
+        return {'success': True,
                 'submission_id': self.cnt,
                 'submission': 'Test submission {cnt}'.format(cnt=self.cnt),
                 'num_graded': 3,
@@ -53,11 +53,11 @@ class MockStaffGradingService(object):
                 'prompt': 'This is a fake prompt',
                 'ml_error_info': 'ML info',
                 'max_score': 2 + self.cnt % 3,
-                           'rubric': 'A rubric'})
+                'rubric': 'A rubric'}
 
     def get_problem_list(self, course_id, grader_id):
         self.cnt += 1
-        return json.dumps({'success': True,
+        return {'success': True,
                  'problem_list': [
                      json.dumps({'location': 'i4x://MITx/3.091x/problem/open_ended_demo1',
                                  'problem_name': "Problem 1", 'num_graded': 3, 'num_pending': 5,
@@ -65,7 +65,7 @@ class MockStaffGradingService(object):
                      json.dumps({'location': 'i4x://MITx/3.091x/problem/open_ended_demo2',
                                  'problem_name': "Problem 2", 'num_graded': 1, 'num_pending': 5,
                                  'min_for_ml': 10})
-                           ]})
+                 ]}
 
     def save_grade(self, course_id, grader_id, submission_id, score, feedback, skipped, rubric_scores,
                    submission_flagged):
@@ -106,7 +106,7 @@ class StaffGradingService(GradingService):
             grader_id: who is grading this?  The anonymous user_id of the grader.
 
         Returns:
-            json string with the response from the service.  (Deliberately not
+            dict with the response from the service.  (Deliberately not
             writing out the fields here--see the docs on the staff_grading view
             in the grading_controller repo)
 
@@ -114,7 +114,7 @@ class StaffGradingService(GradingService):
             GradingServiceError: something went wrong with the connection.
         """
         params = {'course_id': course_id, 'grader_id': grader_id}
-        return self.get(self.get_problem_list_url, params)
+        return self.get(self.get_problem_list_url, params).json()
 
     def get_next(self, course_id, location, grader_id):
         """
@@ -127,7 +127,7 @@ class StaffGradingService(GradingService):
             grader_id: who is grading this?  The anonymous user_id of the grader.
 
         Returns:
-            json string with the response from the service.  (Deliberately not
+            dict with the response from the service.  (Deliberately not
             writing out the fields here--see the docs on the staff_grading view
             in the grading_controller repo)
 
@@ -137,7 +137,7 @@ class StaffGradingService(GradingService):
         response = self.get(self.get_next_url,
                             params={'location': location,
                                     'grader_id': grader_id})
-        return json.dumps(self._render_rubric(response))
+        return self._render_rubric(response.json())
 
     def save_grade(self, course_id, grader_id, submission_id, score, feedback, skipped, rubric_scores,
                    submission_flagged):
@@ -145,7 +145,7 @@ class StaffGradingService(GradingService):
         Save a score and feedback for a submission.
 
         Returns:
-            json dict with keys
+            dict with keys
                 'success': bool
                 'error': error msg, if something went wrong.
 
@@ -162,12 +162,12 @@ class StaffGradingService(GradingService):
                 'rubric_scores_complete': True,
                 'submission_flagged': submission_flagged}
 
-        return self.post(self.save_grade_url, data=data)
+        response = self.post(self.save_grade_url, data=data)
+        return self._render_rubric(response.json())
 
     def get_notifications(self, course_id):
         params = {'course_id': course_id}
-        response = self.get(self.get_notifications_url, params)
-        return response
+        return self.get(self.get_notifications_url, params).json()
 
 
 # don't initialize until staff_grading_service() is called--means that just
@@ -249,7 +249,7 @@ def get_next(request, course_id):
     p = request.POST
     location = p['location']
 
-    return HttpResponse(_get_next(course_id, grader_id, location),
+    return HttpResponse(json.dumps(_get_next(course_id, grader_id, location)),
                         mimetype="application/json")
 
 def get_problem_list(request, course_id):
@@ -278,7 +278,6 @@ def get_problem_list(request, course_id):
     _check_access(request.user, course_id)
     try:
         response = staff_grading_service().get_problem_list(course_id, unique_id_for_user(request.user))
-        response = json.loads(response)
 
         # If 'problem_list' is in the response, then we got a list of problems from the ORA server.
         # If it is not, then ORA could not find any problems.
@@ -373,7 +372,7 @@ def save_grade(request, course_id):
     location = p['location']
 
     try:
-        result_json = staff_grading_service().save_grade(course_id,
+        result = staff_grading_service().save_grade(course_id,
                                                     grader_id,
                                                     p['submission_id'],
                                                     p['score'],
@@ -388,9 +387,6 @@ def save_grade(request, course_id):
                 request, course_id))
         #This is a staff_facing_error
         return _err_response(STAFF_ERROR_MESSAGE)
-
-    try:
-        result = json.loads(result_json)
     except ValueError:
         #This is a dev_facing_error
         log.exception(
@@ -406,7 +402,7 @@ def save_grade(request, course_id):
         return _err_response(STAFF_ERROR_MESSAGE)
 
     # Ok, save_grade seemed to work.  Get the next submission to grade.
-    return HttpResponse(_get_next(course_id, grader_id, location),
+    return HttpResponse(json.dumps(_get_next(course_id, grader_id, location)),
                         mimetype="application/json")
 
 

lms/djangoapps/open_ended_grading/tests.py

@@ -45,7 +45,7 @@ class EmptyStaffGradingService(object):
         """
         Return a staff grading response that is missing a problem list key.
         """
-        return json.dumps({'success': True, 'error': 'No problems found.'})
+        return {'success': True, 'error': 'No problems found.'}
 
 
 def make_instructor(course, user_email):