Add backward compatibility with Pydantic V1 base models

flask_pydantic/converters.py

@@ -6,8 +6,11 @@
     from typing_extensions import get_args, get_origin
 
 from pydantic import BaseModel
+from pydantic.v1 import BaseModel as V1BaseModel
 from werkzeug.datastructures import ImmutableMultiDict
 
+V1OrV2BaseModel = Union[BaseModel, V1BaseModel]
+
 
 def _is_list(type_: Type) -> bool:
     origin = get_origin(type_)
@@ -19,7 +22,7 @@ def _is_list(type_: Type) -> bool:
 
 
 def convert_query_params(
-    query_params: ImmutableMultiDict, model: Type[BaseModel]
+    query_params: ImmutableMultiDict, model: Type[V1OrV2BaseModel]
 ) -> dict:
     """
     group query parameters into lists if model defines them
@@ -28,12 +31,22 @@ def convert_query_params(
     :param model: query parameter's model
     :return: resulting parameters
     """
-    return {
-        **query_params.to_dict(),
-        **{
-            key: value
-            for key, value in query_params.to_dict(flat=False).items()
-            if key in model.model_fields
-            and _is_list(model.model_fields[key].annotation)
-        },
-    }
+    if issubclass(model, BaseModel):
+        return {
+            **query_params.to_dict(),
+            **{
+                key: value
+                for key, value in query_params.to_dict(flat=False).items()
+                if key in model.model_fields
+                and _is_list(model.model_fields[key].annotation)
+            },
+        }
+    else:
+        return {
+            **query_params.to_dict(),
+            **{
+                key: value
+                for key, value in query_params.to_dict(flat=False).items()
+                if key in model.__fields__ and model.__fields__[key].is_complex()
+            },
+        }

flask_pydantic/core.py

@@ -3,7 +3,9 @@
 
 from flask import Response, current_app, jsonify, make_response, request
 from pydantic import BaseModel, ValidationError, TypeAdapter, RootModel
-
+from pydantic.v1 import BaseModel as V1BaseModel
+from pydantic.v1.error_wrappers import ValidationError as V1ValidationError
+from pydantic.v1.tools import parse_obj_as
 from .converters import convert_query_params
 from .exceptions import (
     InvalidIterableOfModelsException,
@@ -17,19 +19,29 @@
 except ImportError:
     pass
 
+V1OrV2BaseModel = Union[BaseModel, V1BaseModel]
+
+
+def _model_dump_json(model: V1OrV2BaseModel, **kwargs):
+    """Adapter to dump a model to json, whether it's a Pydantic V1 or V2 model."""
+    if isinstance(model, BaseModel):
+        return model.model_dump_json(**kwargs)
+    else:
+        return model.json(**kwargs)
+
 
 def make_json_response(
-    content: Union[BaseModel, Iterable[BaseModel]],
+    content: Union[V1OrV2BaseModel, Iterable[V1OrV2BaseModel]],
     status_code: int,
     by_alias: bool,
     exclude_none: bool = False,
     many: bool = False,
 ) -> Response:
     """serializes model, creates JSON response with given status code"""
     if many:
-        js = f"[{', '.join([model.model_dump_json(exclude_none=exclude_none, by_alias=by_alias) for model in content])}]"
+        js = f"[{', '.join([_model_dump_json(model, exclude_none=exclude_none, by_alias=by_alias) for model in content])}]"
     else:
-        js = content.model_dump_json(exclude_none=exclude_none, by_alias=by_alias)
+        js = _model_dump_json(content, exclude_none=exclude_none, by_alias=by_alias)
     response = make_response(js, status_code)
     response.mimetype = "application/json"
     return response
@@ -45,12 +57,14 @@ def unsupported_media_type_response(request_cont_type: str) -> Response:
 
 def is_iterable_of_models(content: Any) -> bool:
     try:
-        return all(isinstance(obj, BaseModel) for obj in content)
+        return all(isinstance(obj, (BaseModel, V1BaseModel)) for obj in content)
     except TypeError:
         return False
 
 
-def validate_many_models(model: Type[BaseModel], content: Any) -> List[BaseModel]:
+def validate_many_models(
+    model: Type[V1OrV2BaseModel], content: Any
+) -> List[V1OrV2BaseModel]:
     try:
         return [model(**fields) for fields in content]
     except TypeError:
@@ -63,7 +77,7 @@ def validate_many_models(model: Type[BaseModel], content: Any) -> List[BaseModel
             }
         ]
         raise ManyModelValidationError(err)
-    except ValidationError as ve:
+    except (ValidationError, V1ValidationError) as ve:
         raise ManyModelValidationError(ve.errors())
 
 
@@ -74,9 +88,13 @@ def validate_path_params(func: Callable, kwargs: dict) -> Tuple[dict, list]:
         if name in {"query", "body", "form", "return"}:
             continue
         try:
-            adapter = TypeAdapter(type_)
-            validated[name] = adapter.validate_python(kwargs.get(name))
-        except ValidationError as e:
+            if not isinstance(type_, V1BaseModel):
+                adapter = TypeAdapter(type_)
+                validated[name] = adapter.validate_python(kwargs.get(name))
+            else:
+                value = parse_obj_as(type_, kwargs.get(name))
+                validated[name] = value
+        except (ValidationError, V1ValidationError) as e:
             err = e.errors()[0]
             err["loc"] = [name]
             errors.append(err)
@@ -92,15 +110,15 @@ def get_body_dict(**params):
 
 
 def validate(
-    body: Optional[Type[BaseModel]] = None,
-    query: Optional[Type[BaseModel]] = None,
+    body: Optional[Type[V1OrV2BaseModel]] = None,
+    query: Optional[Type[V1OrV2BaseModel]] = None,
     on_success_status: int = 200,
     exclude_none: bool = False,
     response_many: bool = False,
     request_body_many: bool = False,
     response_by_alias: bool = False,
     get_json_params: Optional[dict] = None,
-    form: Optional[Type[BaseModel]] = None,
+    form: Optional[Type[V1OrV2BaseModel]] = None,
 ):
     """
     Decorator for route methods which will validate query, body and form parameters
@@ -175,16 +193,24 @@ def wrapper(*args, **kwargs):
                 query_params = convert_query_params(request.args, query_model)
                 try:
                     q = query_model(**query_params)
-                except ValidationError as ve:
+                except (ValidationError, V1ValidationError) as ve:
                     err["query_params"] = ve.errors()
             body_in_kwargs = func.__annotations__.get("body")
             body_model = body_in_kwargs or body
             if body_model:
                 body_params = get_body_dict(**(get_json_params or {}))
-                if issubclass(body_model, RootModel):
+                if (
+                    issubclass(body_model, V1BaseModel)
+                    and "__root__" in body_model.__fields__
+                ):
+                    try:
+                        b = body_model(__root__=body_params).__root__
+                    except (ValidationError, V1ValidationError) as ve:
+                        err["body_params"] = ve.errors()
+                elif issubclass(body_model, RootModel):
                     try:
                         b = body_model(body_params)
-                    except ValidationError as ve:
+                    except (ValidationError, V1ValidationError) as ve:
                         err["body_params"] = ve.errors()
                 elif request_body_many:
                     try:
@@ -201,16 +227,24 @@ def wrapper(*args, **kwargs):
                             return unsupported_media_type_response(content_type)
                         else:
                             raise JsonBodyParsingError()
-                    except ValidationError as ve:
+                    except (ValidationError, V1ValidationError) as ve:
                         err["body_params"] = ve.errors()
             form_in_kwargs = func.__annotations__.get("form")
             form_model = form_in_kwargs or form
             if form_model:
                 form_params = request.form
-                if issubclass(form_model, RootModel):
+                if (
+                    isinstance(form, V1BaseModel)
+                    and "__root__" in form_model.__fields__
+                ):
+                    try:
+                        f = form_model(form_params)
+                    except (ValidationError, V1ValidationError) as ve:
+                        err["form_params"] = ve.errors()
+                elif issubclass(form_model, RootModel):
                     try:
                         f = form_model(form_params)
-                    except ValidationError as ve:
+                    except (ValidationError, V1ValidationError) as ve:
                         err["form_params"] = ve.errors()
                 else:
                     try:
@@ -222,7 +256,7 @@ def wrapper(*args, **kwargs):
                             return unsupported_media_type_response(content_type)
                         else:
                             raise JsonBodyParsingError
-                    except ValidationError as ve:
+                    except (ValidationError, V1ValidationError) as ve:
                         err["form_params"] = ve.errors()
             request.query_params = q
             request.body_params = b
@@ -260,7 +294,7 @@ def wrapper(*args, **kwargs):
                 else:
                     raise InvalidIterableOfModelsException(res)
 
-            if isinstance(res, BaseModel):
+            if isinstance(res, (BaseModel, V1BaseModel)):
                 return make_json_response(
                     res,
                     on_success_status,
@@ -271,7 +305,7 @@ def wrapper(*args, **kwargs):
             if (
                 isinstance(res, tuple)
                 and len(res) in [2, 3]
-                and isinstance(res[0], BaseModel)
+                and isinstance(res[0], (BaseModel, V1BaseModel))
             ):
                 headers = None
                 status = on_success_status

tests/pydantic_v1/conftest.py

@@ -0,0 +1,57 @@
+"""
+Specific confest.py file for testing behavior with Pydantic V1.
+
+The fixtures below override the confest.py's fixtures for this module only.
+"""
+
+from typing import List, Optional, Type
+
+import pytest
+
+from pydantic.v1 import BaseModel
+
+
+@pytest.fixture
+def query_model() -> Type[BaseModel]:
+    class Query(BaseModel):
+        limit: int = 2
+        min_views: Optional[int] = None
+
+    return Query
+
+
+@pytest.fixture
+def body_model() -> Type[BaseModel]:
+    class Body(BaseModel):
+        search_term: str
+        exclude: Optional[str] = None
+
+    return Body
+
+
+@pytest.fixture
+def form_model() -> Type[BaseModel]:
+    class Form(BaseModel):
+        search_term: str
+        exclude: Optional[str] = None
+
+    return Form
+
+
+@pytest.fixture
+def post_model() -> Type[BaseModel]:
+    class Post(BaseModel):
+        title: str
+        text: str
+        views: int
+
+    return Post
+
+
+@pytest.fixture
+def response_model(post_model: BaseModel) -> Type[BaseModel]:
+    class Response(BaseModel):
+        results: List[post_model]
+        count: int
+
+    return Response