option to set validators of pydantic model (#1471)

* option to set validators of pydantic model

* fix: adjust validators of pydantic_model_creator

* update changelog

---------

Co-authored-by: Lucas Brahm <lbrahm@rbi.com>

CHANGELOG.rst

@@ -15,6 +15,7 @@ Added
 ^^^^^
 - Add binary compression support for `UUIDField` in `MySQL`. (#1458)
 - Only `Model`, `Tortoise`, `BaseDBAsyncClient`, `__version__`, and `connections` are now exported from `tortoise`
+- Add parameter `validators` to `pydantic_model_creator`. (#1471)
 
 Fixed
 ^^^^^

tortoise/contrib/pydantic/creator.py

@@ -131,6 +131,7 @@ def pydantic_model_creator(
     exclude_readonly: bool = False,
     meta_override: Optional[Type] = None,
     model_config: Optional[ConfigDict] = None,
+    validators: Optional[Dict[str, Any]] = None,
 ) -> Type[PydanticModel]:
     """
     Function to build `Pydantic Model <https://pydantic-docs.helpmanual.io/usage/models/>`__ off Tortoise Model.
@@ -156,6 +157,7 @@ def pydantic_model_creator(
     :param exclude_readonly: Build a subset model that excludes any readonly fields
     :param meta_override: A PydanticMeta class to override model's values.
     :param model_config: A custom config to use as pydantic config.
+    :param validators: A dictionary of methods that validate fields.
 
         Note: Created pydantic model uses config_class parameter and PydanticMeta's
             config_class as its Config class's bases(Only if provided!), but it
@@ -439,6 +441,7 @@ def get_submodel(_model: "Type[Model]") -> Optional[Type[PydanticModel]]:
     model = create_model(
         _name,
         __base__=PydanticModel,
+        __validators__=validators,
         **properties,
     )
     # Copy the Model docstring over