log and ignore invlaid/deleted courses in Enrollment API

ECOM-1273

common/djangoapps/enrollment/serializers.py

@@ -2,11 +2,16 @@
 Serializers for all Course Enrollment related return objects.
 
 """
+import logging
+
 from rest_framework import serializers
 from student.models import CourseEnrollment
 from course_modes.models import CourseMode
 
 
+log = logging.getLogger(__name__)
+
+
 class StringListField(serializers.CharField):
     """Custom Serializer for turning a comma delimited string into a list.
 
@@ -56,7 +61,28 @@ class CourseEnrollmentSerializer(serializers.ModelSerializer):
     course_details = serializers.SerializerMethodField('get_course_details')
     user = serializers.SerializerMethodField('get_username')
 
+    @property
+    def data(self):
+        serialized_data = super(CourseEnrollmentSerializer, self).data
+
+        # filter the results with empty courses 'course_details'
+        if isinstance(serialized_data, dict):
+            if serialized_data.get('course_details') is None:
+                return None
+
+            return serialized_data
+
+        return [enrollment for enrollment in serialized_data if enrollment.get('course_details')]
+
     def get_course_details(self, model):
+        if model.course is None:
+            msg = u"Course '{0}' does not exist (maybe deleted), in which User (user_id: '{1}') is enrolled.".format(
+                model.course_id,
+                model.user.id
+            )
+            log.warning(msg)
+            return None
+
         field = CourseField()
         return field.to_native(model.course)
 

common/djangoapps/enrollment/tests/test_data.py

@@ -127,6 +127,19 @@ class EnrollmentDataTest(ModuleStoreTestCase):
         results = data.get_course_enrollments(self.user.username)
         self.assertEqual(results, created_enrollments)
 
+        # Now create a course enrollment with some invalid course (does
+        # not exist in database) for the user and check that the method
+        # 'get_course_enrollments' ignores course enrollments for invalid
+        # or deleted courses
+        CourseEnrollment.objects.create(
+            user=self.user,
+            course_id='InvalidOrg/InvalidCourse/InvalidRun',
+            mode='honor',
+            is_active=True
+        )
+        updated_results = data.get_course_enrollments(self.user.username)
+        self.assertEqual(results, updated_results)
+
     @ddt.data(
         # Default (no course modes in the database)
         # Expect that users are automatically enrolled as "honor".