add typing for dependency_overrides_provider

fastapi/dependencies/utils.py

@@ -49,7 +49,7 @@ from fastapi.dependencies.models import Dependant
 from fastapi.exceptions import DependencyScopeError
 from fastapi.logger import logger
 from fastapi.security.oauth2 import SecurityScopes
-from fastapi.types import DependencyCacheKey
+from fastapi.types import DependencyCacheKey, DependencyOverridesProvider
 from fastapi.utils import create_model_field, get_path_param_names
 from pydantic import BaseModel
 from pydantic.fields import FieldInfo
@@ -567,7 +567,7 @@ async def solve_dependencies(
     body: Optional[Union[dict[str, Any], FormData]] = None,
     background_tasks: Optional[StarletteBackgroundTasks] = None,
     response: Optional[Response] = None,
-    dependency_overrides_provider: Optional[Any] = None,
+    dependency_overrides_provider: Optional[DependencyOverridesProvider] = None,
     dependency_cache: Optional[dict[DependencyCacheKey, Any]] = None,
     # TODO: remove this parameter later, no longer used, not removing it yet as some
     # people might be monkey patching this function (although that's not supported)
@@ -599,9 +599,7 @@ async def solve_dependencies(
             and dependency_overrides_provider.dependency_overrides
         ):
             original_call = sub_dependant.call
-            call = getattr(
-                dependency_overrides_provider, "dependency_overrides", {}
-            ).get(original_call, original_call)
+            call = dependency_overrides_provider.dependency_overrides.get(original_call, original_call)
             use_path: str = sub_dependant.path  # type: ignore
             use_sub_dependant = get_dependant(
                 path=use_path,

fastapi/routing.py

@@ -48,7 +48,7 @@ from fastapi.exceptions import (
     ResponseValidationError,
     WebSocketRequestValidationError,
 )
-from fastapi.types import DecoratedCallable, IncEx
+from fastapi.types import DecoratedCallable, IncEx, DependencyOverridesProvider
 from fastapi.utils import (
     create_cloned_field,
     create_model_field,
@@ -257,7 +257,7 @@ def get_request_handler(
     response_model_exclude_unset: bool = False,
     response_model_exclude_defaults: bool = False,
     response_model_exclude_none: bool = False,
-    dependency_overrides_provider: Optional[Any] = None,
+    dependency_overrides_provider: Optional[DependencyOverridesProvider] = None,
     embed_body_fields: bool = False,
 ) -> Callable[[Request], Coroutine[Any, Any, Response]]:
     assert dependant.call is not None, "dependant.call must be a function"
@@ -405,7 +405,7 @@ def get_request_handler(
 
 def get_websocket_app(
     dependant: Dependant,
-    dependency_overrides_provider: Optional[Any] = None,
+    dependency_overrides_provider: Optional[DependencyOverridesProvider] = None,
     embed_body_fields: bool = False,
 ) -> Callable[[WebSocket], Coroutine[Any, Any, Any]]:
     async def app(websocket: WebSocket) -> None:
@@ -448,7 +448,7 @@ class APIWebSocketRoute(routing.WebSocketRoute):
         *,
         name: Optional[str] = None,
         dependencies: Optional[Sequence[params.Depends]] = None,
-        dependency_overrides_provider: Optional[Any] = None,
+        dependency_overrides_provider: Optional[DependencyOverridesProvider] = None,
     ) -> None:
         self.path = path
         self.endpoint = endpoint
@@ -510,7 +510,7 @@ class APIRoute(routing.Route):
         response_class: Union[type[Response], DefaultPlaceholder] = Default(
             JSONResponse
         ),
-        dependency_overrides_provider: Optional[Any] = None,
+        dependency_overrides_provider: Optional[DependencyOverridesProvider] = None,
         callbacks: Optional[list[BaseRoute]] = None,
         openapi_extra: Optional[dict[str, Any]] = None,
         generate_unique_id_function: Union[
@@ -800,7 +800,7 @@ class APIRouter(routing.Router):
             ),
         ] = None,
         dependency_overrides_provider: Annotated[
-            Optional[Any],
+            Optional[DependencyOverridesProvider],
             Doc(
                 """
                 Only used internally by FastAPI to handle dependency overrides.

fastapi/types.py

@@ -1,6 +1,6 @@
 import types
 from enum import Enum
-from typing import Any, Callable, Optional, TypeVar, Union
+from typing import Any, Callable, Optional, TypeVar, Union, Protocol
 
 from pydantic import BaseModel
 
@@ -9,3 +9,6 @@ UnionType = getattr(types, "UnionType", Union)
 ModelNameMap = dict[Union[type[BaseModel], type[Enum]], str]
 IncEx = Union[set[int], set[str], dict[int, Any], dict[str, Any]]
 DependencyCacheKey = tuple[Optional[Callable[..., Any]], tuple[str, ...], str]
+
+class DependencyOverridesProvider(Protocol):
+    dependency_overrides: dict[Callable[..., Any], Any]