From 6341bc38a202c3220bc6d3d7df67da33c6a02114 Mon Sep 17 00:00:00 2001
From: Lucas Wiman <lucas.wiman@akasa.com>
Date: Fri, 24 Jun 2022 10:31:41 -0700
Subject: [PATCH] Traverse __wrapped__ attribute to get to original namespace.

---
 fastapi/dependencies/utils.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py
index f397e333c..08ea969a4 100644
--- a/fastapi/dependencies/utils.py
+++ b/fastapi/dependencies/utils.py
@@ -245,7 +245,13 @@ def is_scalar_sequence_field(field: ModelField) -> bool:
 
 def get_typed_signature(call: Callable[..., Any]) -> inspect.Signature:
     signature = inspect.signature(call)
-    globalns = getattr(call, "__globals__", {})
+    nsobj = call
+    while hasattr(nsobj, "__wrapped__"):
+        # The __wrapped__ attribute is set by decorators, e.g. functools.wraps.
+        # This while loop allows rereferencing forward references on decorated
+        # methods.
+        nsobj = nsobj.__wrapped__
+    globalns = getattr(nsobj, "__globals__", {})
     typed_params = [
         inspect.Parameter(
             name=param.name,