✨ [open-zaak/open-notificaties#156] Pass request as kwarg to Kanaal.g…

…et_kenmerken

and add hook for `_get_field` to support nested attributes in Open Zaak

notifications_api_common/kanalen.py

@@ -1,18 +1,22 @@
 """
 Provide notifications kanaal/exchange classes.
 """
+
 from collections import defaultdict
-from typing import Dict, Tuple
+from typing import Dict, Union
 
 from django.core.exceptions import FieldDoesNotExist, ImproperlyConfigured
-from django.db.models import Model
-from django.db.models.base import ModelBase
+from django.db.models import Field, Model
+
+from rest_framework.request import Request
 
 KANAAL_REGISTRY = set()
 
 
 class Kanaal:
-    def __init__(self, label: str, main_resource: ModelBase, kenmerken: Tuple = None):
+    def __init__(
+        self, label: str, main_resource: Model, kenmerken: Union[tuple, None] = None
+    ):
         self.label = label
         self.main_resource = main_resource
 
@@ -22,7 +26,7 @@ def __init__(self, label: str, main_resource: ModelBase, kenmerken: Tuple = None
         self.kenmerken = kenmerken or ()
         for kenmerk in self.kenmerken:
             try:
-                self.main_resource._meta.get_field(kenmerk)
+                self._get_field(self.main_resource, kenmerk)
             except FieldDoesNotExist as exc:
                 raise ImproperlyConfigured(
                     f"Kenmerk '{kenmerk}' does not exist on the model {main_resource}"
@@ -38,7 +42,18 @@ def __repr__(self):
             self.main_resource,
         )
 
-    def get_kenmerken(self, obj: Model, data: Dict = None) -> Dict:
+    def _get_field(self, model: Model, field: str) -> Field:
+        """
+        Function to retrieve a field from a Model
+        """
+        return model._meta.get_field(field)
+
+    def get_kenmerken(
+        self,
+        obj: Model,
+        data: dict | None = None,
+        request: Request | None = None,  # noqa
+    ) -> Dict:
         data = data or {}
         return {
             kenmerk: data.get(kenmerk, getattr(obj, kenmerk))
@@ -54,7 +69,7 @@ def description(self):
         kenmerken = [
             kenmerk_template.format(
                 kenmerk=kenmerk,
-                help_text=self.main_resource._meta.get_field(kenmerk).help_text,
+                help_text=self._get_field(self.main_resource, kenmerk).help_text,
             )
             for kenmerk in self.kenmerken
         ]

notifications_api_common/viewsets.py

@@ -136,7 +136,9 @@ def construct_message(self, data: dict, instance: models.Model = None) -> dict:
             "actie": self.action,
             "aanmaakdatum": timezone.now(),
             # each channel knows which kenmerken it has, so delegate this
-            "kenmerken": kanaal.get_kenmerken(main_object, main_object_data),
+            "kenmerken": kanaal.get_kenmerken(
+                main_object, main_object_data, request=self.request
+            ),
         }
 
         # let the serializer & render machinery shape the data the way it