🗃️ [#4016] Set up data migration to fix invalid formio configuration

The invalid validate keys are dropped from the existing configuration.

This patch also ensures that old form imports are automatically patched
up during import.

src/openforms/formio/migration_converters.py

@@ -149,10 +149,27 @@ def prevent_datetime_components_from_emptying_invalid_values(
     return True
 
 
+def fix_empty_validate_lengths(component: Component) -> bool:
+    if not (validate := component.get("validate")):
+        return False
+
+    changed = False
+    for key in ("minLength", "maxLength", "min", "max", "minWords", "maxWords"):
+        if key in validate and validate[key] == "":  # type: ignore
+            changed = True
+            del validate[key]  # type: ignore
+
+    return changed
+
+
 CONVERTERS: dict[str, dict[str, ComponentConverter]] = {
     # Input components
     "textfield": {
         "alter_prefill_default_values": alter_prefill_default_values,
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
+    "email": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
     },
     "date": {
         "alter_prefill_default_values": alter_prefill_default_values,
@@ -164,22 +181,43 @@ def prevent_datetime_components_from_emptying_invalid_values(
     "time": {
         "move_time_validators": move_time_validators,
     },
-    "select": {"set_openforms_datasrc": set_openforms_datasrc},
-    "selectboxes": {"set_openforms_datasrc": set_openforms_datasrc},
-    "radio": {"set_openforms_datasrc": set_openforms_datasrc},
+    "phoneNumber": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
     "postcode": {
         "alter_prefill_default_values": alter_prefill_default_values,
         "ensure_validate_pattern": ensure_postcode_validate_pattern,
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
     },
     "file": {
         "fix_default_value": fix_file_default_value,
     },
+    "textarea": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
+    "number": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
+    "select": {"set_openforms_datasrc": set_openforms_datasrc},
+    "selectboxes": {"set_openforms_datasrc": set_openforms_datasrc},
+    "currency": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
+    "radio": {"set_openforms_datasrc": set_openforms_datasrc},
     # Special components
+    "iban": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
     "licenseplate": {
         "ensure_validate_pattern": ensure_licensplate_validate_pattern,
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
     },
     "bsn": {
         "alter_prefill_default_values": alter_prefill_default_values,
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
+    },
+    "cosign": {
+        "fix_empty_validate_lengths": fix_empty_validate_lengths,
     },
     # Layout components
     "columns": {

src/openforms/forms/migrations/0096_fix_invalid_validate_configuration.py

@@ -2,11 +2,25 @@
 
 from django.db import migrations
 
+from openforms.forms.migration_operations import ConvertComponentsOperation
+
 
 class Migration(migrations.Migration):
 
     dependencies = [
         ("forms", "0095_merge_20240313_1742"),
     ]
 
-    operations = []
+    operations = [
+        ConvertComponentsOperation("textfield", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("email", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("phoneNumber", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("postcode", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("textarea", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("number", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("currency", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("iban", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("licenseplate", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("bsn", "fix_empty_validate_lengths"),
+        ConvertComponentsOperation("cosign", "fix_empty_validate_lengths"),
+    ]