✨ [#4606] Implement dynamically resolving the document type

The specified document type is now dynamically resolved within the
case type of the created case, using the submissions completion
time to determine the correct version to use.

The legacy configuration options now emit deprecation warnings, but will
still be supported for the foreseeable future.

src/openforms/contrib/zgw/clients/catalogi.py

@@ -250,6 +250,7 @@ def find_informatieobjecttypen(
         catalogus: str,
         description: str,
         valid_on: date | None = None,
+        within_casetype: str = "",  # URL reference of a case type
     ) -> list[InformatieObjectType] | None:
         """
         Look up an informatieobjecttype within the specified catalogue.
@@ -299,6 +300,19 @@ def find_informatieobjecttypen(
                 f"'{description}'. Version (date) ranges may not overlap."
             )
 
+        if within_casetype:
+            # Filter down the options to those present in the requested case type
+            case_type_response = self.get(within_casetype)
+            case_type_response.raise_for_status()
+            case_type: CaseType = case_type_response.json()
+            case_type_document_types = case_type.get("informatieobjecttypen", [])
+
+            all_versions = [
+                version
+                for version in all_versions
+                if version["url"] in case_type_document_types
+            ]
+
         return all_versions
 
     def list_statustypen(self, zaaktype: str) -> list[dict]:

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

@@ -1,4 +1,5 @@
 import logging
+import warnings
 from datetime import datetime
 from functools import partial, wraps
 from typing import Any, TypedDict
@@ -113,7 +114,7 @@ def _resolve_case_type(
     catalogue: CatalogueOption,
     identification: str,
     submission_completed: datetime,
-):
+) -> str:
     version_valid_on = datetime_in_amsterdam(submission_completed).date()
 
     catalogus = catalogi_client.find_catalogus(**catalogue)
@@ -136,6 +137,37 @@ def _resolve_case_type(
     return version["url"]
 
 
+def _resolve_document_type(
+    catalogi_client: CatalogiClient,
+    catalogue: CatalogueOption,
+    zaaktype_url: str,
+    description: str,
+    submission_completed: datetime,
+):
+    version_valid_on = datetime_in_amsterdam(submission_completed).date()
+
+    catalogus = catalogi_client.find_catalogus(**catalogue)
+    if catalogus is None:
+        raise RuntimeError(f"Could not resolve catalogue {catalogue}")
+    versions = catalogi_client.find_informatieobjecttypen(
+        catalogus=catalogus["url"],
+        description=description,
+        valid_on=version_valid_on,
+        within_casetype=zaaktype_url,
+    )
+    if versions is None:
+        raise RuntimeError(
+            "Could not find a document type with description "
+            f"'{description}' in the case type that is valid on "
+            f"{version_valid_on.isoformat()}."
+        )
+
+    # the client enforces there's a single version returned when a valid_on date is
+    # passed.
+    version = versions[0]
+    return version["url"]
+
+
 @register("zgw-create-zaak")
 class ZGWRegistration(BasePlugin[RegistrationOptions]):
     verbose_name = _("ZGW API's")
@@ -219,6 +251,11 @@ def pre_register_submission(
                     submission.completed_on,
                 )
         else:
+            warnings.warn(
+                "Using the zaaktype URL option is deprecated and will be removed in "
+                "Open Forms 4.0.",
+                DeprecationWarning,
+            )
             zaaktype_url = options["zaaktype"]
 
         with get_zaken_client(zgw) as zaken_client:
@@ -295,9 +332,28 @@ def register_submission(
             get_zaken_client(zgw) as zaken_client,
             get_catalogi_client(zgw) as catalogi_client,
         ):
+            # resolve (default) document type to use
+            if document_type_description := options["document_type_description"]:
+                catalogue = options.get("catalogue")
+                assert catalogue is not None  # enforced by validation
+                informatieobjecttype_url = _resolve_document_type(
+                    catalogi_client,
+                    catalogue=catalogue,
+                    zaaktype_url=zaak["zaaktype"],
+                    description=document_type_description,
+                    submission_completed=submission.completed_on,
+                )
+            else:
+                warnings.warn(
+                    "Using the informatieobjecttype URL option is deprecated and will "
+                    "be removed in Open Forms 4.0.",
+                    DeprecationWarning,
+                )
+                informatieobjecttype_url = options["informatieobjecttype"]
+
             # Upload the summary PDF
             pdf_options: DocumentOptions = {
-                "informatieobjecttype": options["informatieobjecttype"],
+                "informatieobjecttype": informatieobjecttype_url,
                 "organisatie_rsin": options["organisatie_rsin"],
                 "auteur": options["auteur"],
                 "doc_vertrouwelijkheidaanduiding": options[
@@ -387,7 +443,7 @@ def register_submission(
             for attachment in submission.attachments:
                 # collect attributes of the attachment and add them to the configuration
                 # attribute names conform to the Documenten API specification
-                iot = attachment.informatieobjecttype or options["informatieobjecttype"]
+                iot = attachment.informatieobjecttype or informatieobjecttype_url
                 bronorganisatie = (
                     attachment.bronorganisatie or options["organisatie_rsin"]
                 )