🎨 [#4398] Decouple variables endpoint validation behaviour from plugi…

…n details

The important pattern is that certain validation checks run, not the
implementation details of the objects api prefill plugin. So, we
can properly isolate this by setting up a different plugin
registry and doing the dependency injection through a helper,
applying the same pattern as with registration plugins.

src/openforms/forms/tests/variables/test_viewset.py

@@ -6,7 +6,7 @@
 from django.utils.translation import gettext_lazy as _
 
 from factory.django import FileField
-from rest_framework import status
+from rest_framework import serializers, status
 from rest_framework.reverse import reverse
 from rest_framework.test import APITestCase
 from zgw_consumers.constants import APITypes, AuthTypes
@@ -23,6 +23,8 @@
     FormStepFactory,
     FormVariableFactory,
 )
+from openforms.prefill.contrib.demo.plugin import DemoPrefill
+from openforms.prefill.tests.utils import get_test_register, patch_prefill_registry
 from openforms.variables.constants import (
     DataMappingTypes,
     FormVariableDataTypes,
@@ -903,6 +905,23 @@ def test_validators_accepts_only_numeric_keys(self):
         self.assertEqual(status.HTTP_200_OK, response.status_code)
 
     def test_bulk_create_and_update_with_prefill_constraints(self):
+        # Isolate the prefill registry/plugins for this test - we care about the pattern,
+        # not about particular plugin implementation details
+        new_register = get_test_register()
+
+        class OptionsSerializer(serializers.Serializer):
+            foo = serializers.CharField(required=True, allow_blank=False)
+
+        class OptionsPrefill(DemoPrefill):
+            options = OptionsSerializer
+
+        new_register("demo-options")(OptionsPrefill)
+
+        # set up registry patching for the test
+        cm = patch_prefill_registry(new_register)
+        cm.__enter__()
+        self.addCleanup(lambda: cm.__exit__(None, None, None))
+
         user = StaffUserFactory.create(user_permissions=["change_form"])
         self.client.force_authenticate(user)
 
@@ -1033,9 +1052,9 @@ def test_bulk_create_and_update_with_prefill_constraints(self):
                     "service_fetch_configuration": None,
                     "data_type": FormVariableDataTypes.string,
                     "source": FormVariableSources.user_defined,
-                    "prefill_plugin": "objects_api",
+                    "prefill_plugin": "demo-options",
                     "prefill_attribute": "",
-                    "prefill_options": {"foo": "bar", "auth_attribute_path": ["bsn"]},
+                    "prefill_options": {"foo": "bar"},
                 }
             ]
 

src/openforms/prefill/service.py

@@ -39,15 +39,18 @@
 
 import elasticapm
 
-from openforms.formio.service import FormioConfigurationWrapper
+from openforms.formio.service import (
+    FormioConfigurationWrapper,
+    normalize_value_for_component,
+)
 from openforms.submissions.models import Submission
 from openforms.submissions.models.submission_value_variable import (
     SubmissionValueVariable,
 )
 from openforms.typing import JSONEncodable
 from openforms.variables.constants import FormVariableSources
 
-from .registry import Registry
+from .registry import Registry, register as default_register
 from .sources import (
     fetch_prefill_values_from_attribute,
     fetch_prefill_values_from_options,
@@ -71,9 +74,6 @@ def inject_prefill(
     The prefill values are looped over by key: value, and for each value the matching
     component is looked up to normalize it in the context of the component.
     """
-
-    from openforms.formio.service import normalize_value_for_component
-
     prefilled_data = submission.get_prefilled_data()
     for key, prefill_value in prefilled_data.items():
         try:
@@ -111,10 +111,6 @@ def prefill_variables(submission: Submission, register: Registry | None = None)
     be used to fetch the value. If ``register`` is not specified, the default registry instance
     will be used.
     """
-    from openforms.formio.service import normalize_value_for_component
-
-    from .registry import register as default_register
-
     register = register or default_register
 
     state = submission.load_submission_value_variables_state()

src/openforms/prefill/tests/test_prefill_hook.py

@@ -21,10 +21,9 @@
 from ..contrib.demo.plugin import DemoPrefill
 from ..registry import Registry, register as prefill_register
 from ..service import inject_prefill, prefill_variables
+from .utils import get_test_register
 
-register = Registry()
-
-register("demo")(DemoPrefill)
+register = get_test_register()
 
 CONFIGURATION = {
     "display": "form",