refactor: split assignment serializer into admin vs. non-admin

This gives the benefit of allowing us to remove duplicate code
(in-memory calculations of recent_action + learner_state).

ENT-7780

enterprise_access/apps/api/serializers/__init__.py

@@ -1,7 +1,10 @@
 """
 API serializers module.
 """
-from .content_assignments.assignment import LearnerContentAssignmentResponseSerializer
+from .content_assignments.assignment import (
+    LearnerContentAssignmentAdminResponseSerializer,
+    LearnerContentAssignmentResponseSerializer
+)
 from .content_assignments.assignment_configuration import (
     AssignmentConfigurationCreateRequestSerializer,
     AssignmentConfigurationDeleteRequestSerializer,

enterprise_access/apps/api/serializers/content_assignments/assignment.py

@@ -43,9 +43,11 @@ class LearnerContentAssignmentRecentActionSerializer(serializers.Serializer):
     action_type = serializers.ChoiceField(
         help_text='Type of the recent action.',
         choices=AssignmentRecentActionTypes.CHOICES,
+        source='recent_action',
     )
     timestamp = serializers.DateTimeField(
         help_text='Date and time when the action was taken.',
+        source='recent_action_time',
     )
 
 
@@ -60,18 +62,6 @@ class LearnerContentAssignmentResponseSerializer(serializers.ModelSerializer):
         help_text='All actions associated with this assignment.',
         many=True,
     )
-    recent_action = LearnerContentAssignmentRecentActionSerializer(
-        help_text='Structured data about the most recent action. Meant to power a frontend table column.',
-        source='get_recent_action_data',
-    )
-    learner_state = serializers.ChoiceField(
-        help_text=(
-            'learner_state is an admin-facing dynamic state, not to be confused with `state`. Meant to power a '
-            'frontend table column.'
-        ),
-        choices=AssignmentLearnerStates.CHOICES,
-        source='get_learner_state',
-    )
 
     class Meta:
         model = LearnerContentAssignment
@@ -86,6 +76,32 @@ class Meta:
             'transaction_uuid',
             'last_notification_at',
             'actions',
+        ]
+        read_only_fields = fields
+
+
+class LearnerContentAssignmentAdminResponseSerializer(LearnerContentAssignmentResponseSerializer):
+    """
+    A read-only Serializer for responding to requests for ``LearnerContentAssignment`` records FOR ADMINS.
+
+    Important: This serializer depends on extra dynamic fields annotated by calling
+    ``LearnerContentAssignment.annotate_dynamic_fields_onto_queryset()`` on the assignment queryset.
+    """
+
+    recent_action = LearnerContentAssignmentRecentActionSerializer(
+        help_text='Structured data about the most recent action. Meant to power a frontend table column.',
+        source='*',
+    )
+    learner_state = serializers.ChoiceField(
+        help_text=(
+            'learner_state is an admin-facing dynamic state, not to be confused with `state`. Meant to power a '
+            'frontend table column.'
+        ),
+        choices=AssignmentLearnerStates.CHOICES,
+    )
+
+    class Meta(LearnerContentAssignmentResponseSerializer.Meta):
+        fields = LearnerContentAssignmentResponseSerializer.Meta.fields + [
             'recent_action',
             'learner_state',
         ]

enterprise_access/apps/api/v1/tests/test_allocation_view.py

@@ -147,11 +147,6 @@ def test_allocate_happy_path(self, mock_allocate, mock_can_allocate):
                     'transaction_uuid': None,
                     'uuid': str(self.alice_assignment.uuid),
                     'actions': [],
-                    'recent_action': {
-                        'action_type': AssignmentRecentActionTypes.ASSIGNED,
-                        'timestamp': self.alice_assignment.created.strftime('%Y-%m-%dT%H:%M:%S.%fZ'),
-                    },
-                    'learner_state': None,
                 },
             ],
             'created': [
@@ -166,11 +161,6 @@ def test_allocate_happy_path(self, mock_allocate, mock_can_allocate):
                     'transaction_uuid': None,
                     'uuid': str(self.bob_assignment.uuid),
                     'actions': [],
-                    'recent_action': {
-                        'action_type': AssignmentRecentActionTypes.ASSIGNED,
-                        'timestamp': self.bob_assignment.created.strftime('%Y-%m-%dT%H:%M:%S.%fZ'),
-                    },
-                    'learner_state': AssignmentLearnerStates.NOTIFYING,
                 },
             ],
             'no_change': [
@@ -185,11 +175,6 @@ def test_allocate_happy_path(self, mock_allocate, mock_can_allocate):
                     'transaction_uuid': None,
                     'uuid': str(self.carol_assignment.uuid),
                     'actions': [],
-                    'recent_action': {
-                        'action_type': AssignmentRecentActionTypes.ASSIGNED,
-                        'timestamp': self.carol_assignment.created.strftime('%Y-%m-%dT%H:%M:%S.%fZ'),
-                    },
-                    'learner_state': AssignmentLearnerStates.NOTIFYING,
                 },
             ],
         }
@@ -420,11 +405,6 @@ def test_allocate_happy_path_e2e(
                     'transaction_uuid': None,
                     'uuid': str(new_allocation.uuid),
                     'actions': [],
-                    'recent_action': {
-                        'action_type': AssignmentRecentActionTypes.ASSIGNED,
-                        'timestamp': new_allocation.created.strftime('%Y-%m-%dT%H:%M:%S.%fZ'),
-                    },
-                    'learner_state': AssignmentLearnerStates.NOTIFYING,
                 },
             ],
             'no_change': [],

enterprise_access/apps/api/v1/tests/test_assignment_views.py

@@ -593,11 +593,6 @@ def test_retrieve(self, role_context_dict):
                 }
                 for action in self.requester_assignment_accepted.actions.order_by('completed_at')
             ],
-            'recent_action': {
-                'action_type': AssignmentRecentActionTypes.ASSIGNED,
-                'timestamp': self.requester_assignment_accepted.created.strftime('%Y-%m-%dT%H:%M:%S.%fZ'),
-            },
-            'learner_state': None,
         }
 
     def test_retrieve_other_assignment_not_found(self):

enterprise_access/apps/api/v1/views/content_assignments/assignments.py

@@ -61,6 +61,10 @@ def get_queryset(self):
         """
         A base queryset to list or retrieve ``LearnerContentAssignment`` records.  In this viewset, only the assignments
         assigned to the requester are returned.
+
+        Unlike in LearnerContentAssignmentAdminViewSet, here we are not going to annotate the extra dynamic fields using
+        `annotate_dynamic_fields_onto_queryset()`, so we will NOT serialize `learner_state` and `recent_action` for each
+        assignment.
         """
         return LearnerContentAssignment.objects.filter(
             learner_email=self.requesting_user_email,

enterprise_access/apps/api/v1/views/content_assignments/assignments_admin.py

@@ -46,7 +46,7 @@ class LearnerContentAssignmentAdminViewSet(
     Viewset supporting all Admin CRUD operations on ``LearnerContentAssignment`` records.
     """
     permission_classes = (permissions.IsAuthenticated,)
-    serializer_class = serializers.LearnerContentAssignmentResponseSerializer
+    serializer_class = serializers.LearnerContentAssignmentAdminResponseSerializer
     authentication_classes = (JwtAuthentication, authentication.SessionAuthentication)
     filter_backends = (filters.NoFilterOnDetailBackend, OrderingFilter)
     filterset_class = filters.LearnerContentAssignmentAdminFilter
@@ -94,7 +94,7 @@ def get_queryset(self):
         tags=[CONTENT_ASSIGNMENT_ADMIN_CRUD_API_TAG],
         summary='Retrieve a content assignment by UUID.',
         responses={
-            status.HTTP_200_OK: serializers.LearnerContentAssignmentResponseSerializer,
+            status.HTTP_200_OK: serializers.LearnerContentAssignmentAdminResponseSerializer,
             status.HTTP_404_NOT_FOUND: None,  # TODO: test that this actually returns 404 instead of 403 on RBAC error.
         },
     )
@@ -120,7 +120,7 @@ def list(self, request, *args, **kwargs):
         tags=[CONTENT_ASSIGNMENT_ADMIN_CRUD_API_TAG],
         summary='Cancel an assignment by UUID.',
         responses={
-            status.HTTP_200_OK: serializers.LearnerContentAssignmentResponseSerializer,
+            status.HTTP_200_OK: serializers.LearnerContentAssignmentAdminResponseSerializer,
             status.HTTP_404_NOT_FOUND: None,
             status.HTTP_422_UNPROCESSABLE_ENTITY: None,
         },
@@ -150,7 +150,7 @@ def cancel(self, request, *args, uuid=None, **kwargs):
             # Serialize the assignment object obtained via get_queryset() instead of the one from the assignments_api.
             # Only the former has the additional dynamic fields annotated, and those are required for serialization.
             assignment_to_cancel.refresh_from_db()
-            response_serializer = serializers.LearnerContentAssignmentResponseSerializer(assignment_to_cancel)
+            response_serializer = serializers.LearnerContentAssignmentAdminResponseSerializer(assignment_to_cancel)
             return Response(response_serializer.data, status=status.HTTP_200_OK)
         else:
             return Response(status=status.HTTP_422_UNPROCESSABLE_ENTITY)

enterprise_access/apps/content_assignments/models.py

@@ -294,66 +294,6 @@ def add_successful_reminded_action(self):
             completed_at=timezone.now(),
         )
 
-    def get_recent_action_data(self):
-        """
-        Return structured data about the most recent action, meant to feed the serializer.
-
-        Recent action can ONLY be one of:
-        * AssignmentRecentActionTypes.REMINDED: Most recent ``reminded`` action.
-        * AssignmentRecentActionTypes.ASSIGNED: Assignment record creation event, if no reminded actions exist.
-
-        Notes:
-        * These are not 1:1 with EITHER the AssignmentAction types, OR internal lifecycle states of assignments.
-          Instead it is a hybrid of both.
-        * This logic duplicates what is performed in annotate_dynamic_fields_onto_queryset() to annotate the
-          `recent_action` and `recent_action_time` fields on an assignment queryset.  We rely on the serializer to
-          function even when the assignment object is not derived from a viewset's get_queryset().
-
-        Returns:
-            dict: {
-                'action_type': <one of AssignmentRecentActionTypes>,
-                'timestamp': <time of recent action>,
-            }
-        """
-        reminded_actions = self.actions.filter(action_type=AssignmentActions.REMINDED)
-        if len(reminded_actions) > 0:
-            recent_action_type = AssignmentRecentActionTypes.REMINDED
-            recent_action_time = reminded_actions.order_by('completed_at').last().completed_at
-        else:
-            recent_action_type = AssignmentRecentActionTypes.ASSIGNED
-            recent_action_time = self.created
-        return {
-            'action_type': recent_action_type,
-            'timestamp': recent_action_time,
-        }
-
-    def get_learner_state(self):
-        """
-        Returns the learner state of this assignment (not to be confused with state).
-
-        Notes:
-        * learner_state is not 1:1 with EITHER the AssignmentAction types, OR internal lifecycle states of assignments.
-          Instead it is a hybrid of both.
-        * This logic duplicates what is performed in annotate_dynamic_fields_onto_queryset() to annotate the
-          `learner_state` field on an assignment queryset.  We rely on the serializer to function even when the
-          assignment object is not derived from a viewset's get_queryset().
-
-        Returns:
-            str: One of AssignmentLearnerStates, or None if the assignment doesn't map to one.
-        """
-        has_notification = bool(LearnerContentAssignmentAction.objects.filter(
-            assignment=self,
-            action_type=AssignmentActions.NOTIFIED,
-        ))
-        if self.state == LearnerContentAssignmentStateChoices.ALLOCATED and not has_notification:
-            return AssignmentLearnerStates.NOTIFYING
-        elif self.state == LearnerContentAssignmentStateChoices.ALLOCATED and has_notification:
-            return AssignmentLearnerStates.WAITING
-        elif self.state == LearnerContentAssignmentStateChoices.ERRORED and has_notification:
-            return AssignmentLearnerStates.FAILED
-        else:
-            return None
-
     @classmethod
     def annotate_dynamic_fields_onto_queryset(cls, queryset):
         """
@@ -366,8 +306,7 @@ def annotate_dynamic_fields_onto_queryset(cls, queryset):
         * recent_action_time (DateTimeField)
 
         Notes:
-        * This class method duplicates the logic found in instance methods get_learner_state() and
-          get_recent_action_data(), but using pure ORM queryset logic instead of in-memory calculations.
+        * In order to use LearnerContentAssignmentAdminResponseSerializer, you must call this method on the queryset.
 
         Args:
             queryset (QuerySet): LearnerContentAssignment queryset, vanilla.