✨ [#4908] Add typing hints for json registration options

src/openforms/registrations/contrib/json/config.py

@@ -1,3 +1,5 @@
+from typing import Required, TypedDict
+
 from django.utils.translation import gettext_lazy as _
 
 from rest_framework import serializers
@@ -28,3 +30,15 @@ class JSONOptionsSerializer(JsonSchemaSerializerMixin, serializers.Serializer):
             "A comma-separated list of form variables (can also include static variables) to use."
         )
     )
+
+
+class JSONOptions(TypedDict):
+    """
+    JSON registration plugin options
+
+    This describes the shape of :attr:`JSONOptionsSerializer.validated_data`, after
+    the input data has been cleaned/validated.
+    """
+    service: Required[Service]
+    relative_api_endpoint: str
+    form_variables: Required[list[str]]

src/openforms/registrations/contrib/json/plugin.py

@@ -7,20 +7,19 @@
 from openforms.submissions.models import Submission
 from openforms.variables.service import get_static_variables
 
-from ...base import BasePlugin, OptionsT  # openforms.registrations.base
+from ...base import BasePlugin  # openforms.registrations.base
 from ...registry import register  # openforms.registrations.registry
 from ...utils import execute_unless_result_exists
-from .config import JSONOptionsSerializer
+from .config import JSONOptions, JSONOptionsSerializer
 
 
 @register("json")
 class JSONRegistration(BasePlugin):
     verbose_name = _("JSON registration")
     configuration_options = JSONOptionsSerializer
 
-    def register_submission(self, submission: Submission, options: OptionsT) -> None:
+    def register_submission(self, submission: Submission, options: JSONOptions) -> dict:
         # TODO-4908: the email plugin works with a EmailConfig singleton model. Is that useful here?
-        # TODO-4908: add typing for options dict
 
         # TODO-4908: any other form field types that need 'special attention'?