From 8a05f569a411cfe56cd87a5fc5b78c26738fd1d6 Mon Sep 17 00:00:00 2001
From: bahtya <bahtyar153@qq.com>
Date: Mon, 6 Apr 2026 11:04:43 +0800
Subject: [PATCH] Fix get_path_param_names to strip path converters

The regex {(.*?)} captures 'param:path' instead of 'param' when path
converters are used. This causes implicit path params to be incorrectly
treated as query params.

Fix: use {([^:}]+)} to stop at the colon separator.

Fixes #14883
---
 fastapi/utils.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fastapi/utils.py b/fastapi/utils.py
index 12eaa2bf08..3aa1f2e3b3 100644
--- a/fastapi/utils.py
+++ b/fastapi/utils.py
@@ -41,7 +41,7 @@ def is_body_allowed_for_status_code(status_code: int | str | None) -> bool:
 
 
 def get_path_param_names(path: str) -> set[str]:
-    return set(re.findall("{(.*?)}", path))
+    return set(re.findall("{([^:}]+)", path))
 
 
 _invalid_args_message = (