EDUCATOR-4189 | Account for undefined values in commerce API Course objects.

lms/djangoapps/commerce/api/v1/models.py

@@ -12,6 +12,8 @@ from openedx.core.djangoapps.content.course_overviews.models import CourseOvervi
 
 log = logging.getLogger(__name__)
 
+UNDEFINED = object()
+
 
 class Course(object):
     """ Pseudo-course model used to group CourseMode objects. """
@@ -19,10 +21,12 @@ class Course(object):
     modes = None
     _deleted_modes = None
 
-    def __init__(self, id, modes, verification_deadline=None):  # pylint: disable=redefined-builtin
+    def __init__(self, id, modes, **kwargs):  # pylint: disable=redefined-builtin
         self.id = CourseKey.from_string(unicode(id))  # pylint: disable=invalid-name
         self.modes = list(modes)
-        self.verification_deadline = verification_deadline
+        self.verification_deadline = UNDEFINED
+        if 'verification_deadline' in kwargs:
+            self.verification_deadline = kwargs['verification_deadline']
         self._deleted_modes = []
 
     @property
@@ -59,8 +63,10 @@ class Course(object):
     def save(self, *args, **kwargs):  # pylint: disable=unused-argument
         """ Save the CourseMode objects to the database. """
 
-        # Override the verification deadline for the course (not the individual modes)
-        VerificationDeadline.set_deadline(self.id, self.verification_deadline, is_explicit=True)
+        if self.verification_deadline is not UNDEFINED:
+            # Override the verification deadline for the course (not the individual modes)
+            # This will delete verification deadlines for the course if self.verification_deadline is null
+            VerificationDeadline.set_deadline(self.id, self.verification_deadline, is_explicit=True)
 
         for mode in self.modes:
             mode.course_id = self.id
@@ -73,7 +79,10 @@ class Course(object):
 
     def update(self, attrs):
         """ Update the model with external data (usually passed via API call). """
-        self.verification_deadline = attrs.get('verification_deadline')
+        # There are possible downstream effects of settings self.verification_deadline to null,
+        # so don't assign it a value here unless it is specifically included in attrs.
+        if 'verification_deadline' in attrs:
+            self.verification_deadline = attrs.get('verification_deadline')
 
         existing_modes = {mode.mode_slug: mode for mode in self.modes}
         merged_modes = set()

lms/djangoapps/commerce/api/v1/serializers.py

@@ -10,7 +10,7 @@ from rest_framework import serializers
 from course_modes.models import CourseMode
 from xmodule.modulestore.django import modulestore
 
-from .models import Course
+from .models import Course, UNDEFINED
 
 
 class CourseModeSerializer(serializers.ModelSerializer):
@@ -56,11 +56,22 @@ def validate_course_id(course_id):
         )
 
 
+class PossiblyUndefinedDateTimeField(serializers.DateTimeField):
+    """
+    We need a DateTime serializer that can deal with the non-JSON-serializable
+    UNDEFINED object.
+    """
+    def to_representation(self, value):
+        if value is UNDEFINED:
+            return None
+        return super(PossiblyUndefinedDateTimeField, self).to_representation(value)
+
+
 class CourseSerializer(serializers.Serializer):
     """ Course serializer. """
     id = serializers.CharField(validators=[validate_course_id])  # pylint: disable=invalid-name
     name = serializers.CharField(read_only=True)
-    verification_deadline = serializers.DateTimeField(format=None, allow_null=True, required=False)
+    verification_deadline = PossiblyUndefinedDateTimeField(format=None, allow_null=True, required=False)
     modes = CourseModeSerializer(many=True)
 
     def validate(self, attrs):
@@ -87,11 +98,23 @@ class CourseSerializer(serializers.Serializer):
         return attrs
 
     def create(self, validated_data):
-        """Create course modes for a course. """
+        """
+        Create course modes for a course.
+
+        arguments:
+            validated_data: The result of self.validate() - a dictionary containing 'id', 'modes', and optionally
+            a 'verification_deadline` key.
+        returns:
+            A ``commerce.api.v1.models.Course`` object.
+        """
+        kwargs = {}
+        if 'verification_deadline' in validated_data:
+            kwargs['verification_deadline'] = validated_data['verification_deadline']
+
         course = Course(
             validated_data["id"],
             self._new_course_mode_models(validated_data["modes"]),
-            verification_deadline=validated_data["verification_deadline"]
+            **kwargs
         )
         course.save()
         return course

lms/djangoapps/commerce/api/v1/tests/test_views.py

@@ -128,8 +128,9 @@ class CourseRetrieveUpdateViewTests(CourseApiViewTestMixin, ModuleStoreTestCase)
 
     @ddt.data('post', 'put')
     def test_authorization_required(self, method):
-        self.user.user_permissions.clear()
         """ Verify create/edit operations require appropriate permissions. """
+        self.user.user_permissions.clear()
+
         response = getattr(self.client, method)(self.path, content_type=JSON_CONTENT_TYPE)
         self.assertEqual(response.status_code, 403)
 
@@ -236,6 +237,32 @@ class CourseRetrieveUpdateViewTests(CourseApiViewTestMixin, ModuleStoreTestCase)
         self.assertEqual(response.status_code, 200)
         self.assertIsNone(VerificationDeadline.deadline_for_course(self.course.id))
 
+    def test_update_verification_deadline_left_alone(self):
+        """
+        When the course's verification deadline is set and an update request doesn't
+        include it, we should take no action on it.
+        """
+        verification_deadline = datetime(year=1915, month=5, day=7, tzinfo=pytz.utc)
+        response, __ = self._get_update_response_and_expected_data(None, verification_deadline)
+        self.assertEqual(VerificationDeadline.deadline_for_course(self.course.id), verification_deadline)
+
+        verified_mode = CourseMode(
+            mode_slug=u'verified',
+            min_price=200,
+            currency=u'USD',
+            sku=u'ABC123',
+            bulk_sku=u'BULK-ABC123',
+            expiration_datetime=None
+        )
+        updated_data = self._serialize_course(self.course, [verified_mode], None)
+        # don't include the verification_deadline key in the PUT request
+        updated_data.pop('verification_deadline', None)
+
+        response = self.client.put(self.path, json.dumps(updated_data), content_type=JSON_CONTENT_TYPE)
+
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(VerificationDeadline.deadline_for_course(self.course.id), verification_deadline)
+
     def test_remove_upgrade_deadline(self):
         """
         Verify that course mode upgrade deadlines can be removed through the API.