wip: fix using a separate manager

enterprise/api/v1/serializers.py

@@ -41,16 +41,6 @@
 )
 from enterprise.validators import validate_pgp_key
 
-try:
-    from common.djangoapps.student.models import CourseEnrollment
-except ImportError:
-    CourseEnrollment = None
-
-try:
-    from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
-except ImportError:
-    CourseOverview = None
-
 LOGGER = getLogger(__name__)
 User = auth.get_user_model()
 
@@ -336,8 +326,7 @@ class EnterpriseCourseEnrollmentReadOnlySerializer(serializers.ModelSerializer):
     class Meta:
         model = models.EnterpriseCourseEnrollment
         fields = (
-            'enterprise_customer_user',
-            'course_id',
+            'enterprise_customer_user', 'course_id',
         )
 
 
@@ -346,44 +335,25 @@ class EnterpriseCourseEnrollmentWithAdditionalFieldsReadOnlySerializer(Enterpris
     Serializer for EnterpriseCourseEnrollment model with additional fields.
     """
 
-    def to_representation(self, instance):
-        representation = super().to_representation(instance)
-        representation.update(self._get_additional_fields(instance))
-        return representation
-
-    def _get_additional_fields(self, instance):
-        """
-        Return annotations with additional data for the queryset.
-        Additional fields are None in the test environment, where platform models are not available.
-        """
-
-        if not CourseEnrollment or not CourseOverview:
-            return {
-                'enrollment_track': None,
-                'enrollment_date': None,
-                'user_email': None,
-                'course_start': None,
-                'course_end': None,
-            }
-
-        user = auth.get_user_model().objects.filter(
-            id=instance.enterprise_customer_user.user_id,
-        ).first()
-        enrollment = CourseEnrollment.objects.filter(
-            user=user,
-            course_id=instance.course_id,
-        ).first()
-        course_overview = CourseOverview.objects.filter(
-            id=instance.course_id,
-        ).first()
+    class Meta:
+        model = models.EnterpriseCourseEnrollment
+        fields = (
+            'enterprise_customer_user',
+            'course_id',
+            'enterprise_customer_user',
+            'course_id',
+            'enrollment_date',
+            'enrollment_track',
+            'user_email',
+            'course_start',
+            'course_end',
+        )
 
-        return {
-            'enrollment_track': getattr(enrollment, 'mode', None),
-            'enrollment_date': getattr(enrollment, 'created', None),
-            'user_email': getattr(user, 'email', None),
-            'course_start': getattr(course_overview, 'start', None),
-            'course_end': getattr(course_overview, 'end', None),
-        }
+    enrollment_track = serializers.CharField()
+    enrollment_date = serializers.DateTimeField()
+    user_email = serializers.EmailField()
+    course_start = serializers.DateTimeField()
+    course_end = serializers.DateTimeField()
 
 
 class EnterpriseCourseEnrollmentWriteSerializer(serializers.ModelSerializer):

enterprise/api/v1/views.py

@@ -531,7 +531,7 @@ class EnterpriseCourseEnrollmentViewSet(EnterpriseReadWriteModelViewSet):
     API views for the ``enterprise-course-enrollment`` API endpoint.
     """
 
-    queryset = models.EnterpriseCourseEnrollment.objects.all()
+    queryset = models.EnterpriseCourseEnrollment.with_additional_fields.all()
     filter_backends = (filters.OrderingFilter, DjangoFilterBackend, EnterpriseCourseEnrollmentFilterBackend)
 
     USER_ID_FILTER = 'enterprise_customer_user__user_id'

enterprise/models.py

@@ -87,6 +87,11 @@
 except ImportError:
     CourseEntitlement = None
 
+try:
+    from openedx.core.djangoapps.content.course_overviews.models import CourseOverview
+except ImportError:
+    CourseOverview = None
+
 LOGGER = getLogger(__name__)
 User = auth.get_user_model()
 mark_safe_lazy = lazy(mark_safe, str)
@@ -1786,6 +1791,54 @@ def get_queryset(self):
             enterprise_customer_user__linked=True
         )
 
+class EnterpriseCourseEnrollmentWithAdditionalFieldsManager(models.Manager):
+    """
+    Model manager for `EnterpriseCourseEnrollment`.
+    """
+
+    def get_queryset(self):
+        """
+        Override to return only those enrollment records for which learner is linked to an enterprise.
+        """
+
+        return super().get_queryset().select_related('enterprise_customer_user').filter(
+            enterprise_customer_user__linked=True
+        ).annotate(**self._get_additional_data_annotations())
+
+    def _get_additional_data_annotations(self):
+        """
+        Return annotations with additional data for the queryset.
+        Additional fields are None in the test environment, where platform models are not available.
+        """
+
+        if not CourseEnrollment or not CourseOverview:
+            return {
+                'enrollment_track': models.Value(None, output_field=models.CharField()),
+                'enrollment_date': models.Value(None, output_field=models.DateTimeField()),
+                'user_email': models.Value(None, output_field=models.EmailField()),
+                'course_start': models.Value(None, output_field=models.DateTimeField()),
+                'course_end': models.Value(None, output_field=models.DateTimeField()),
+            }
+
+        enrollment_subquery = CourseEnrollment.objects.filter(
+            user=models.OuterRef('enterprise_customer_user__user_id'),
+            course_id=models.OuterRef('course_id'),
+        )
+        user_subquery = auth.get_user_model().objects.filter(
+            id=models.OuterRef('enterprise_customer_user__user_id'),
+        ).values('email')[:1]
+        course_subquery = CourseOverview.objects.filter(
+            id=models.OuterRef('course_id'),
+        )
+
+        return {
+            'enrollment_track': models.Subquery(enrollment_subquery.values('mode')[:1]),
+            'enrollment_date': models.Subquery(enrollment_subquery.values('created')[:1]),
+            'user_email': models.Subquery(user_subquery),
+            'course_start': models.Subquery(course_subquery.values('start')[:1]),
+            'course_end': models.Subquery(course_subquery.values('end')[:1]),
+        }
+
 
 class EnterpriseCourseEnrollment(TimeStampedModel):
     """
@@ -1806,6 +1859,7 @@ class EnterpriseCourseEnrollment(TimeStampedModel):
     """
 
     objects = EnterpriseCourseEnrollmentManager()
+    with_additional_fields = EnterpriseCourseEnrollmentWithAdditionalFieldsManager()
 
     class Meta:
         unique_together = (('enterprise_customer_user', 'course_id',),)