Add support for functools.partial()-wrapped dependables

fastapi/dependencies/utils.py

@@ -1,6 +1,7 @@
 import inspect
 from contextlib import AsyncExitStack, contextmanager
 from copy import deepcopy
+from functools import partial
 from typing import (
     Any,
     Callable,
@@ -487,10 +488,10 @@ def add_param_to_fields(*, field: ModelField, dependant: Dependant) -> None:
 
 
 def is_coroutine_callable(call: Callable[..., Any]) -> bool:
-    if inspect.isroutine(call):
+    if inspect.iscoroutinefunction(call):
-        return inspect.iscoroutinefunction(call)
+        return True
-    if inspect.isclass(call):
+    if isinstance(call, partial):
-        return False
+        return is_coroutine_callable(call.func)
     dunder_call = getattr(call, "__call__", None)  # noqa: B004
     return inspect.iscoroutinefunction(dunder_call)
 
@@ -498,6 +499,8 @@ def is_coroutine_callable(call: Callable[..., Any]) -> bool:
 def is_async_gen_callable(call: Callable[..., Any]) -> bool:
     if inspect.isasyncgenfunction(call):
         return True
+    if isinstance(call, partial):
+        return is_async_gen_callable(call.func)
     dunder_call = getattr(call, "__call__", None)  # noqa: B004
     return inspect.isasyncgenfunction(dunder_call)
 
@@ -505,6 +508,8 @@ def is_async_gen_callable(call: Callable[..., Any]) -> bool:
 def is_gen_callable(call: Callable[..., Any]) -> bool:
     if inspect.isgeneratorfunction(call):
         return True
+    if isinstance(call, partial):
+        return is_gen_callable(call.func)
     dunder_call = getattr(call, "__call__", None)  # noqa: B004
     return inspect.isgeneratorfunction(dunder_call)
 

tests/test_dependency_types.py

@@ -1,4 +1,5 @@
 from typing import AsyncGenerator, Generator
+from functools import partial
 
 import pytest
 from fastapi import Depends, FastAPI
@@ -64,6 +65,26 @@ async_callable_gen_dependency = AsyncCallableGenDependency()
 methods_dependency = MethodsDependency()
 
 
+@app.get("/function-dependency")
+async def get_function_dependency(value: str = Depends(function_dependency)) -> str:
+    return value
+
+
+@app.get("/async-function-dependency")
+async def get_async_function_dependency(value: str = Depends(async_function_dependency)) -> str:
+    return value
+
+
+@app.get("/gen-dependency")
+async def get_gen_dependency(value: str = Depends(gen_dependency)) -> str:
+    return value
+
+
+@app.get("/async-gen-dependency")
+async def get_async_gen_dependency(value: str = Depends(async_gen_dependency)) -> str:
+    return value
+
+
 @app.get("/callable-dependency")
 async def get_callable_dependency(value: str = Depends(callable_dependency)) -> str:
     return value
@@ -116,6 +137,78 @@ async def get_asynchronous_method_gen_dependency(
     return value
 
 
+@app.get("/partial-function-dependency")
+async def get_partial_function_dependency(value: str = Depends(partial(function_dependency, "partial-function-dependency"))) -> str:
+    return value
+
+
+@app.get("/partial-async-function-dependency")
+async def get_partial_async_function_dependency(value: str = Depends(partial(async_function_dependency, "partial-async-function-dependency"))) -> str:
+    return value
+
+
+@app.get("/partial-gen-dependency")
+async def get_partial_gen_dependency(value: str = Depends(partial(gen_dependency, "partial-gen-dependency"))) -> str:
+    return value
+
+
+@app.get("/partial-async-gen-dependency")
+async def get_partial_async_gen_dependency(value: str = Depends(partial(async_gen_dependency, "partial-async-gen-dependency"))) -> str:
+    return value
+
+
+@app.get("/partial-callable-dependency")
+async def get_partial_callable_dependency(value: str = Depends(partial(callable_dependency, "partial-callable-dependency"))) -> str:
+    return value
+
+
+@app.get("/partial-callable-gen-dependency")
+async def get_partial_callable_gen_dependency(value: str = Depends(partial(callable_gen_dependency, "partial-callable-gen-dependency"))) -> str:
+    return value
+
+
+@app.get("/partial-async-callable-dependency")
+async def get_partial_async_callable_dependency(
+    value: str = Depends(partial(async_callable_dependency, "partial-async-callable-dependency")),
+) -> str:
+    return value
+
+
+@app.get("/partial-async-callable-gen-dependency")
+async def get_partial_async_callable_gen_dependency(
+    value: str = Depends(partial(async_callable_gen_dependency, "partial-async-callable-gen-dependency")),
+) -> str:
+    return value
+
+
+@app.get("/partial-synchronous-method-dependency")
+async def get_partial_synchronous_method_dependency(
+    value: str = Depends(partial(methods_dependency.synchronous, "partial-synchronous-method-dependency")),
+) -> str:
+    return value
+
+
+@app.get("/partial-synchronous-method-gen-dependency")
+async def get_partial_synchronous_method_gen_dependency(
+    value: str = Depends(partial(methods_dependency.synchronous_gen, "partial-synchronous-method-gen-dependency")),
+) -> str:
+    return value
+
+
+@app.get("/partial-asynchronous-method-dependency")
+async def get_partial_asynchronous_method_dependency(
+    value: str = Depends(partial(methods_dependency.asynchronous, "partial-asynchronous-method-dependency")),
+) -> str:
+    return value
+
+
+@app.get("/partial-asynchronous-method-gen-dependency")
+async def get_partial_asynchronous_method_gen_dependency(
+    value: str = Depends(partial(methods_dependency.asynchronous_gen, "partial-asynchronous-method-gen-dependency")),
+) -> str:
+    return value
+
+
 client = TestClient(app)
 
 
@@ -140,3 +233,26 @@ def test_dependency_types(route: str, value: str) -> None:
     response = client.get(route, params={"value": value})
     assert response.status_code == 200, response.text
     assert response.json() == value
+
+
+@pytest.mark.parametrize(
+    "route,value",
+    [
+        ("/partial-function-dependency", "partial-function-dependency"),
+        ("/partial-async-function-dependency", "partial-async-function-dependency"),
+        ("/partial-gen-dependency", "partial-gen-dependency"),
+        ("/partial-async-gen-dependency", "partial-async-gen-dependency"),
+        ("/partial-callable-dependency", "partial-callable-dependency"),
+        ("/partial-callable-gen-dependency", "partial-callable-gen-dependency"),
+        ("/partial-async-callable-dependency", "partial-async-callable-dependency"),
+        ("/partial-async-callable-gen-dependency", "partial-async-callable-gen-dependency"),
+        ("/partial-synchronous-method-dependency", "partial-synchronous-method-dependency"),
+        ("/partial-synchronous-method-gen-dependency", "partial-synchronous-method-gen-dependency"),
+        ("/partial-asynchronous-method-dependency", "partial-asynchronous-method-dependency"),
+        ("/partial-asynchronous-method-gen-dependency", "partial-asynchronous-method-gen-dependency"),
+    ],
+)
+def test_dependency_types_with_partial(route: str, value: str) -> None:
+    response = client.get(route)
+    assert response.status_code == 200, response.text
+    assert response.json() == value