From 0b0b4fe4d5220d77b34ee4fe3aa91cd6afd1b1ef Mon Sep 17 00:00:00 2001
From: Fliksh <fliksh@ro.ru>
Date: Mon, 26 Feb 2024 14:20:32 +0400
Subject: [PATCH 1/4] Fix call async routes decorated with class based
 decorator

---
 fastapi/routing.py                            |  7 +++-
 ...est_endpoint_with_async_class_decorator.py | 32 +++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 tests/test_endpoint_with_async_class_decorator.py

diff --git a/fastapi/routing.py b/fastapi/routing.py
index 23a32d15f..70dbd0323 100644
--- a/fastapi/routing.py
+++ b/fastapi/routing.py
@@ -208,7 +208,12 @@ def get_request_handler(
     dependency_overrides_provider: Optional[Any] = None,
 ) -> Callable[[Request], Coroutine[Any, Any, Response]]:
     assert dependant.call is not None, "dependant.call must be a function"
-    is_coroutine = asyncio.iscoroutinefunction(dependant.call)
+    if inspect.isfunction(dependant.call):
+        is_coroutine = asyncio.iscoroutinefunction(dependant.call)
+    else:
+        is_coroutine = asyncio.iscoroutinefunction(
+            getattr(dependant.call, "__call__", dependant.call)  # noqa: B004
+        )
     is_body_form = body_field and isinstance(body_field.field_info, params.Form)
     if isinstance(response_class, DefaultPlaceholder):
         actual_response_class: Type[Response] = response_class.value
diff --git a/tests/test_endpoint_with_async_class_decorator.py b/tests/test_endpoint_with_async_class_decorator.py
new file mode 100644
index 000000000..d8ac561d5
--- /dev/null
+++ b/tests/test_endpoint_with_async_class_decorator.py
@@ -0,0 +1,32 @@
+from functools import update_wrapper
+
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+
+class SomeDecorator:
+    def __init__(self, original_route):
+        update_wrapper(wrapper=self, wrapped=original_route)
+        self.route = original_route
+
+    async def __call__(self, *args, **kwargs):
+        return await self.route(*args, **kwargs)
+
+
+data = {"working": True}
+
+
+@SomeDecorator
+async def route():
+    return data
+
+
+app = FastAPI()
+app.get("/")(route)
+
+client = TestClient(app)
+
+
+def test_endpoint_with_async_class_decorator():
+    response = client.get("/")
+    assert data == response.json()

From 806965144161be97b1dc73975881aaf401ead611 Mon Sep 17 00:00:00 2001
From: Motov Yurii <109919500+YuriiMotov@users.noreply.github.com>
Date: Tue, 22 Jul 2025 19:20:55 +0200
Subject: [PATCH 2/4] Simplify the code of test

---
 tests/test_endpoint_with_async_class_decorator.py | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/tests/test_endpoint_with_async_class_decorator.py b/tests/test_endpoint_with_async_class_decorator.py
index d8ac561d5..c75823b18 100644
--- a/tests/test_endpoint_with_async_class_decorator.py
+++ b/tests/test_endpoint_with_async_class_decorator.py
@@ -13,20 +13,14 @@ class SomeDecorator:
         return await self.route(*args, **kwargs)
 
 
-data = {"working": True}
-
-
+@app.get("/")
 @SomeDecorator
-async def route():
-    return data
-
-
-app = FastAPI()
-app.get("/")(route)
+async def route1():
+    return {"working": True}
 
 client = TestClient(app)
 
 
 def test_endpoint_with_async_class_decorator():
     response = client.get("/")
-    assert data == response.json()
+    assert response.json() == {"working": True}

From e44030b95a52b2e12db9bb6306e6e30c36c0acae Mon Sep 17 00:00:00 2001
From: Motov Yurii <109919500+YuriiMotov@users.noreply.github.com>
Date: Tue, 22 Jul 2025 19:24:01 +0200
Subject: [PATCH 3/4] Fix test

---
 tests/test_endpoint_with_async_class_decorator.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/test_endpoint_with_async_class_decorator.py b/tests/test_endpoint_with_async_class_decorator.py
index c75823b18..da322ef66 100644
--- a/tests/test_endpoint_with_async_class_decorator.py
+++ b/tests/test_endpoint_with_async_class_decorator.py
@@ -13,6 +13,8 @@ class SomeDecorator:
         return await self.route(*args, **kwargs)
 
 
+app = FastAPI()
+
 @app.get("/")
 @SomeDecorator
 async def route1():

From 2eb2fcbd7611076a063f96f0435a63e4e2d166c2 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Tue, 22 Jul 2025 17:25:57 +0000
Subject: [PATCH 4/4] =?UTF-8?q?=F0=9F=8E=A8=20[pre-commit.ci]=20Auto=20for?=
 =?UTF-8?q?mat=20from=20pre-commit.com=20hooks?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 tests/test_endpoint_with_async_class_decorator.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/test_endpoint_with_async_class_decorator.py b/tests/test_endpoint_with_async_class_decorator.py
index da322ef66..a5e225103 100644
--- a/tests/test_endpoint_with_async_class_decorator.py
+++ b/tests/test_endpoint_with_async_class_decorator.py
@@ -15,11 +15,13 @@ class SomeDecorator:
 
 app = FastAPI()
 
+
 @app.get("/")
 @SomeDecorator
 async def route1():
     return {"working": True}
 
+
 client = TestClient(app)