From 87c63ec343a1a51e8ce67ddf4763eb6384eb05c0 Mon Sep 17 00:00:00 2001
From: Juergen Eger <11678629+jeger-at@users.noreply.github.com>
Date: Tue, 29 Apr 2025 08:04:04 +0000
Subject: [PATCH] openapi template resources with more than 1 path parameter is
 not supported #267

---
 src/fastmcp/server/openapi.py | 4 +++-
 tests/server/test_openapi.py  | 4 ++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/fastmcp/server/openapi.py b/src/fastmcp/server/openapi.py
index 88539ff65..a2dd3e21e 100644
--- a/src/fastmcp/server/openapi.py
+++ b/src/fastmcp/server/openapi.py
@@ -286,12 +286,14 @@ class OpenAPIResource(Resource):
                     # Find the path parameter names from the route path
                     param_matches = re.findall(r"\{([^}]+)\}", path)
                     if param_matches:
+                        # Reverse sorting from creation order (traversal is backwards)
+                        param_matches.sort(reverse=True)
                         # Number of sent parameters is number of parts -1 (assuming first part is resource identifier)
                         expected_param_count = len(parts) -1
                         # Map parameters from the end of the URI to the parameters in the path
                         # Last parameter in URI (parts[-1]) maps to last parameter in path, and so on
                         for i, param_name in enumerate(param_matches):
-                            if i < len(expected_param_count):  # Ensure we don't use resource identifier as parameter
+                            if i < expected_param_count:  # Ensure we don't use resource identifier as parameter
                                 param_value = parts[-1-i]  # Get values from the end of parts
                                 path_params[param_name] = param_value
 
diff --git a/tests/server/test_openapi.py b/tests/server/test_openapi.py
index 5d0506648..091b158db 100644
--- a/tests/server/test_openapi.py
+++ b/tests/server/test_openapi.py
@@ -53,7 +53,7 @@ def fastapi_app(users_db: dict[int, User]) -> FastAPI:
     
     @app.get("/users/{user_id}/{is_active}", tags=["users", "detail"])
     async def get_user_active_state(user_id: int, is_active: bool) -> User | None:
-        """Get a user by ID."""
+        """Get a user by ID and filter by active state."""
         user = users_db.get(user_id)
         if user is not None and user.active == is_active:
             return user
@@ -359,7 +359,7 @@ class TestResourceTemplates:
         is_active = True
         async with Client(fastmcp_openapi_server) as client:
             resource_response = await client.read_resource(
-                f"resource://openapi/get_user_users__user_type__user_id__get/{user_id}/{is_active}"
+                f"resource://openapi/get_user_active_state_users__user_id___is_active__get/{is_active}/{user_id}"
             )
             assert isinstance(resource_response[0], TextResourceContents)
             response_text = resource_response[0].text