From dacc29a2d57b38ed2c0ce303c38394ce03296cba Mon Sep 17 00:00:00 2001
From: "Dave St.Germain" <dstgermain@edx.org>
Date: Mon, 8 Jul 2019 11:37:49 -0400
Subject: [PATCH] Fixed saving exams to backend when there's a due date set

---
 edx_proctoring/__init__.py                 | 2 +-
 edx_proctoring/backends/rest.py            | 7 +++++--
 edx_proctoring/backends/tests/test_rest.py | 6 ++++++
 edx_proctoring/serializers.py              | 7 +++++++
 edx_proctoring/signals.py                  | 8 ++++----
 5 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/edx_proctoring/__init__.py b/edx_proctoring/__init__.py
index e8fcfa3d825..7ca7d921567 100644
--- a/edx_proctoring/__init__.py
+++ b/edx_proctoring/__init__.py
@@ -5,6 +5,6 @@
 from __future__ import absolute_import
 
 # Be sure to update the version number in edx_proctoring/package.json
-__version__ = '2.0.4'
+__version__ = '2.0.5'
 
 default_app_config = 'edx_proctoring.apps.EdxProctoringConfig'  # pylint: disable=invalid-name
diff --git a/edx_proctoring/backends/rest.py b/edx_proctoring/backends/rest.py
index a3546580e38..ca45cf15e36 100644
--- a/edx_proctoring/backends/rest.py
+++ b/edx_proctoring/backends/rest.py
@@ -266,8 +266,11 @@ def on_exam_saved(self, exam):
             response = self.session.post(url, json=exam)
             data = response.json()
         except Exception as exc:  # pylint: disable=broad-except
-            # pylint: disable=no-member
-            content = exc.response.content if hasattr(exc, 'response') else response.content
+            if response:
+                # pylint: disable=no-member
+                content = exc.response.content if hasattr(exc, 'response') else response.content
+            else:
+                content = None
             log.exception('failed to save exam. %r', content)
             data = {}
         return data.get('id')
diff --git a/edx_proctoring/backends/tests/test_rest.py b/edx_proctoring/backends/tests/test_rest.py
index d0139135a57..a628ed8d9dd 100644
--- a/edx_proctoring/backends/tests/test_rest.py
+++ b/edx_proctoring/backends/tests/test_rest.py
@@ -166,6 +166,12 @@ def test_failed_exam_save(self):
         external_id = self.provider.on_exam_saved(self.backend_exam)
         self.assertEqual(external_id, None)
 
+    @responses.activate
+    def test_bad_exam_save(self):
+        self.backend_exam['bad'] = object()
+        external_id = self.provider.on_exam_saved(self.backend_exam)
+        self.assertEqual(external_id, None)
+
     @responses.activate
     def test_register_exam_attempt(self):
         context = {
diff --git a/edx_proctoring/serializers.py b/edx_proctoring/serializers.py
index 6bb6e59602f..59ce8b6eaa3 100644
--- a/edx_proctoring/serializers.py
+++ b/edx_proctoring/serializers.py
@@ -46,6 +46,13 @@ class Meta:
         )
 
 
+class ProctoredExamJSONSafeSerializer(ProctoredExamSerializer):
+    """
+    ProctoredExam serializer which will return dates as strings.
+    """
+    due_date = serializers.DateTimeField(required=False)
+
+
 class UserSerializer(serializers.ModelSerializer):
     """
     Serializer for the User Model.
diff --git a/edx_proctoring/signals.py b/edx_proctoring/signals.py
index 05fef5b7a0d..41a89db2ff1 100644
--- a/edx_proctoring/signals.py
+++ b/edx_proctoring/signals.py
@@ -22,8 +22,8 @@ def check_for_category_switch(sender, instance, **kwargs):  # pylint: disable=un
     if instance.id:
         original = sender.objects.get(pk=instance.id)
         if original.is_proctored and instance.is_proctored != original.is_proctored:
-            from edx_proctoring.serializers import ProctoredExamSerializer
-            exam = ProctoredExamSerializer(instance).data
+            from edx_proctoring.serializers import ProctoredExamJSONSafeSerializer
+            exam = ProctoredExamJSONSafeSerializer(instance).data
             # from the perspective of the backend, the exam is now inactive.
             exam['is_active'] = False
             backend = get_backend_provider(name=exam['backend'])
@@ -44,8 +44,8 @@ def save_exam_on_backend(sender, instance, **kwargs):  # pylint: disable=unused-
         exam_obj = instance.proctored_exam
         review_policy = instance
     if exam_obj.is_proctored:
-        from edx_proctoring.serializers import ProctoredExamSerializer
-        exam = ProctoredExamSerializer(exam_obj).data
+        from edx_proctoring.serializers import ProctoredExamJSONSafeSerializer
+        exam = ProctoredExamJSONSafeSerializer(exam_obj).data
         if review_policy:
             exam['rule_summary'] = review_policy.review_policy
         backend = get_backend_provider(exam)