feat: cancel pending assignment functionality

fix: refactored code based on reviewer feedback

fix: allow non-opaque-keys as content key for allocate requests

fix: data migration to delete Actions sans Assignments, and use on_delete=CASCADE (#314)

chore: allow optional logging of Django's SQL

fix: missing content titles on assignments

feat: Try to populate lms_user_id on assignments during creation

This is an attempt to cover the case where learners are already
logged in at the moment of assignment.  This case is a hole left by the
work in ENT-7875 which only set out to cover the case where a learner
was logged out at the moment of assignment.

ENT-7874

feat: Added assignments in credits_available endpoint

feat: allowing consumers of the learner content assignment api to filter by email and content title

fix: lint error

chore: refactored

fix: updated failing tests

feat: fetch enterprise catalog content metadata, serialize for credits_available assignments

ENT-7878

feat: add course_type field to assignment content metadata serializer

feat: return `learner_state_counts` as part of the admin assignments list API response (#322)

feat: validate requested allocation price

feat: link learners during assignment allocation

ENT-7778 | Call task to link learners to enterprise customer during allocation,
and have that ask add a successful linked action.

fix: new approach to generate `learner_state_count` in admin assignments list API; add addtl ordering and filtering support (#324)

chore: rebase

fix: lint error

chore: added test coverage

enterprise_access/apps/api/filters/base.py

@@ -1,9 +1,14 @@
 """
 Base FilterSet utility classes.
 """
+from django_filters import BaseInFilter, CharFilter
 from django_filters import rest_framework as drf_filters
 
 
+class CharInFilter(BaseInFilter, CharFilter):
+    pass
+
+
 class HelpfulFilterSet(drf_filters.FilterSet):
     """
     Using an explicit FilterSet object works nicely with drf-spectacular

enterprise_access/apps/api/filters/content_assignments.py

@@ -2,7 +2,7 @@
 API Filters for resources defined in the ``assignment_policy`` app.
 """
 from ...content_assignments.models import AssignmentConfiguration, LearnerContentAssignment
-from .base import HelpfulFilterSet
+from .base import CharInFilter, HelpfulFilterSet
 
 
 class AssignmentConfigurationFilter(HelpfulFilterSet):
@@ -18,11 +18,14 @@ class LearnerContentAssignmentAdminFilter(HelpfulFilterSet):
     """
     Base filter for LearnerContentAssignment views.
     """
+    learner_state = CharInFilter(field_name='learner_state', lookup_expr='in')
+
     class Meta:
         model = LearnerContentAssignment
         fields = [
             'content_key',
             'learner_email',
             'lms_user_id',
             'state',
+            'learner_state',
         ]

enterprise_access/apps/api/serializers/__init__.py

@@ -2,6 +2,7 @@
 API serializers module.
 """
 from .content_assignments.assignment import (
+    ContentMetadataForAssignmentSerializer,
     LearnerContentAssignmentAdminResponseSerializer,
     LearnerContentAssignmentResponseSerializer
 )

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

@@ -7,7 +7,6 @@
 from rest_framework import serializers
 
 from enterprise_access.apps.content_assignments.constants import (
-    AssignmentActions,
     AssignmentLearnerStates,
     AssignmentRecentActionTypes,
     LearnerContentAssignmentStateChoices
@@ -24,6 +23,8 @@ class LearnerContentAssignmentActionSerializer(serializers.ModelSerializer):
     class Meta:
         model = LearnerContentAssignmentAction
         fields = [
+            'created',
+            'modified',
             'uuid',
             'action_type',
             'completed_at',
@@ -100,10 +101,130 @@ class LearnerContentAssignmentAdminResponseSerializer(LearnerContentAssignmentRe
         ),
         choices=AssignmentLearnerStates.CHOICES,
     )
+    error_reason = serializers.SerializerMethodField()
 
     class Meta(LearnerContentAssignmentResponseSerializer.Meta):
         fields = LearnerContentAssignmentResponseSerializer.Meta.fields + [
             'recent_action',
             'learner_state',
+            'error_reason',
         ]
         read_only_fields = fields
+
+    @extend_schema_field(serializers.CharField)
+    def get_error_reason(self, assignment):
+        """
+        Resolves the error reason for the assignment, if any, for display purposes based on
+        any associated actions.
+        """
+        # If the assignment is not in an errored state, there should be no error reason.
+        if assignment.state != LearnerContentAssignmentStateChoices.ERRORED:
+            return None
+
+        # Assignment is an errored state, so determine the appropriate error reason so clients don't need to.
+        related_actions_with_error = assignment.actions.filter(error_reason__isnull=False).order_by('-created')
+        if not related_actions_with_error:
+            logger.warning(
+                'LearnerContentAssignment with UUID %s is in an errored state, but has no related '
+                'actions in an error state.',
+                assignment.uuid,
+            )
+            return None
+
+        # Get the most recently errored action.
+        return related_actions_with_error.first().error_reason
+
+
+class CoursePartnerSerializer(serializers.Serializer):
+    """
+    Serialized partner ``name`` and ``logo_image_url`` for content_metadata of an assignment.
+    """
+    name = serializers.CharField(help_text='The partner name')
+    logo_image_url = serializers.CharField(help_text='The URL for the parter logo image')
+
+
+class ContentMetadataForAssignmentSerializer(serializers.Serializer):
+    """
+    Serializer to help return additional content metadata for assignments.  These fields should
+    map more or less 1-1 to the fields in content metadata dicts returned from the
+    enterprise-catalog `get_content_metadata` response payload.
+    """
+    start_date = serializers.SerializerMethodField(
+        help_text='The start date of the course',
+    )
+    end_date = serializers.SerializerMethodField(
+        help_text='The end date of the course',
+    )
+    enroll_by_date = serializers.SerializerMethodField(
+        help_text='The date by which the learner must accept/enroll',
+    )
+    content_price = serializers.SerializerMethodField(
+        help_text='The price, in USD, of this content',
+    )
+    course_type = serializers.CharField(
+        help_text='The type of course, something like "executive-education-2u" or "verified-audit"',
+        # Try to be a little defensive against malformed data.
+        required=False,
+        allow_null=True,
+    )
+    partners = serializers.SerializerMethodField()
+
+    @extend_schema_field(serializers.DateTimeField)
+    def get_start_date(self, obj):
+        return obj.get('normalized_metadata', {}).get('start_date')
+
+    @extend_schema_field(serializers.DateTimeField)
+    def get_end_date(self, obj):
+        return obj.get('normalized_metadata', {}).get('end_date')
+
+    @extend_schema_field(serializers.DateTimeField)
+    def get_enroll_by_date(self, obj):
+        return obj.get('normalized_metadata', {}).get('enroll_by_date')
+
+    @extend_schema_field(serializers.IntegerField)
+    def get_content_price(self, obj):
+        return obj.get('normalized_metadata', {}).get('content_price')
+
+    @extend_schema_field(CoursePartnerSerializer)
+    def get_partners(self, obj):
+        """
+        See ``get_course_partners()`` in
+        enterprise-catalog/enterprise_catalog/apps/catalog/algolia_utils.py
+        """
+        partners = []
+        owners = obj.get('owners') or []
+
+        for owner in owners:
+            partner_name = owner.get('name')
+            if partner_name:
+                partner_metadata = {
+                    'name': partner_name,
+                    'logo_image_url': owner.get('logo_image_url'),
+                }
+                partners.append(partner_metadata)
+
+        return CoursePartnerSerializer(partners, many=True).data
+
+
+class LearnerContentAssignmentWithContentMetadataResponseSerializer(LearnerContentAssignmentResponseSerializer):
+    """
+    Read-only serializer for LearnerContentAssignment records that also includes additional content metadata,
+    fetched from the catalog service (or cache).
+    """
+    content_metadata = serializers.SerializerMethodField(
+        help_text='Additional content metadata fetched from the catalog service or cache.',
+    )
+
+    class Meta(LearnerContentAssignmentResponseSerializer.Meta):
+        fields = LearnerContentAssignmentResponseSerializer.Meta.fields + ['content_metadata']
+        read_only_fields = fields
+
+    @extend_schema_field(ContentMetadataForAssignmentSerializer)
+    def get_content_metadata(self, obj):
+        """
+        Serializers content metadata for the assignment, if available.
+        """
+        metadata_lookup = self.context.get('content_metadata')
+        if metadata_lookup and (assignment_content_metadata := metadata_lookup.get(obj.content_key)):
+            return ContentMetadataForAssignmentSerializer(assignment_content_metadata).data
+        return None

enterprise_access/apps/api/serializers/subsidy_access_policy.py

@@ -13,10 +13,14 @@
 from requests.exceptions import HTTPError
 from rest_framework import serializers
 
+from enterprise_access.apps.content_assignments.api import get_content_metadata_for_assignments
 from enterprise_access.apps.subsidy_access_policy.constants import CENTS_PER_DOLLAR, PolicyTypes
 from enterprise_access.apps.subsidy_access_policy.models import SubsidyAccessPolicy
 
-from .content_assignments.assignment import LearnerContentAssignmentResponseSerializer
+from .content_assignments.assignment import (
+    LearnerContentAssignmentResponseSerializer,
+    LearnerContentAssignmentWithContentMetadataResponseSerializer
+)
 from .content_assignments.assignment_configuration import AssignmentConfigurationResponseSerializer
 
 logger = logging.getLogger(__name__)
@@ -340,8 +344,14 @@ class SubsidyAccessPolicyCreditsAvailableRequestSerializer(serializers.Serialize
 
     For view: SubsidyAccessPolicyRedeemViewset.credits_available
     """
-    enterprise_customer_uuid = serializers.UUIDField(required=True)
-    lms_user_id = serializers.IntegerField(required=True)
+    enterprise_customer_uuid = serializers.UUIDField(
+        required=True,
+        help_text='The customer for which available policies are filtered.',
+    )
+    lms_user_id = serializers.IntegerField(
+        required=True,
+        help_text='The user identifier for which available policies are filtered.',
+    )
 
 
 # pylint: disable=abstract-method
@@ -519,17 +529,44 @@ class SubsidyAccessPolicyCreditsAvailableResponseSerializer(SubsidyAccessPolicyR
         help_text='Remaining balance on the entire subsidy, in USD cents.',
     )
     subsidy_expiration_date = serializers.DateTimeField(
-        help_text='',
+        help_text='The date at which the related Subsidy record expires.',
         source='subsidy_expiration_datetime',
     )
+    learner_content_assignments = serializers.SerializerMethodField('get_assignments_serializer')
+
+    @extend_schema_field(LearnerContentAssignmentWithContentMetadataResponseSerializer)
+    def get_assignments_serializer(self, obj):
+        """
+        Return serialized assignments if the policy access method is of the 'assigned' type
+        """
+        if not obj.is_assignable:
+            return []
+
+        assignments = obj.assignment_configuration.assignments.prefetch_related('actions').filter(
+            lms_user_id=self.context.get('lms_user_id')
+        )
+        content_metadata_lookup = get_content_metadata_for_assignments(obj.catalog_uuid, assignments)
+        context = {'content_metadata': content_metadata_lookup}
+        serializer = LearnerContentAssignmentWithContentMetadataResponseSerializer(
+            assignments,
+            many=True,
+            context=context,
+        )
+        return serializer.data
 
     @extend_schema_field(serializers.IntegerField)
     def get_remaining_balance_per_user(self, obj):
-        lms_user_id = self.context.get('lms_user_id')
-        return obj.remaining_balance_per_user(lms_user_id=lms_user_id)
+        """
+        The remaining balance per user for this policy, in USD cents, if applicable.
+        """
+        if hasattr(obj, 'remaining_balance_per_user'):
+            lms_user_id = self.context.get('lms_user_id')
+            return obj.remaining_balance_per_user(lms_user_id=lms_user_id)
+        return None
 
     @extend_schema_field(serializers.IntegerField)
     def get_remaining_balance(self, obj):
+        """Returns the remaining balance for the policy"""
         return obj.subsidy_balance()
 
 
@@ -604,7 +641,7 @@ class SubsidyAccessPolicyAllocateRequestSerializer(serializers.Serializer):
         allow_empty=False,
         help_text='Learner emails to whom LearnerContentAssignments should be allocated.',
     )
-    content_key = ContentKeyField(
+    content_key = serializers.CharField(
         required=True,
         help_text='Course content_key to which these learners are assigned.',
     )