policies/api: fix target returning pbm_uuid instead of proper primary key of the object

passbook/lib/api.py

@@ -0,0 +1,36 @@
+"""passbook API Helpers"""
+from django.core.exceptions import ObjectDoesNotExist
+from django.db.models.query import QuerySet
+from model_utils.managers import InheritanceQuerySet
+from rest_framework.serializers import ModelSerializer, PrimaryKeyRelatedField
+
+
+class InheritancePrimaryKeyRelatedField(PrimaryKeyRelatedField):
+    """rest_framework PrimaryKeyRelatedField which resolves
+    model_manager's InheritanceQuerySet"""
+
+    def get_queryset(self) -> QuerySet:
+        queryset = super().get_queryset()
+        if isinstance(queryset, InheritanceQuerySet):
+            return queryset.select_subclasses()
+        return queryset
+
+    def to_internal_value(self, data):
+        if self.pk_field is not None:
+            data = self.pk_field.to_internal_value(data)
+        try:
+            queryset = self.get_queryset()
+            if isinstance(queryset, InheritanceQuerySet):
+                return queryset.get_subclass(pk=data)
+            return queryset.get(pk=data)
+        except ObjectDoesNotExist:
+            self.fail("does_not_exist", pk_value=data)
+        except (TypeError, ValueError):
+            self.fail("incorrect_type", data_type=type(data).__name__)
+
+
+class InheritanceModelSerializer(ModelSerializer):
+    """rest_framework ModelSerializer which automatically uses InheritancePrimaryKeyRelatedField
+    for every primary key"""
+
+    serializer_related_field = InheritancePrimaryKeyRelatedField