Use helper method to avoid code duplication

fastapi/routing.py

@@ -879,12 +879,9 @@ class APIRouter(routing.Router):
         name: Optional[str] = None,
         include_in_schema: bool = True,
     ) -> Callable[[DecoratedCallable], DecoratedCallable]:
-        if self.ignore_trailing_slash:
-            path = path.rstrip("/")
-
         def decorator(func: DecoratedCallable) -> DecoratedCallable:
             self.add_route(
-                path,
+                self._normalize_path(path),
                 func,
                 methods=methods,
                 name=name,
@@ -928,8 +925,7 @@ class APIRouter(routing.Router):
             Callable[[APIRoute], str], DefaultPlaceholder
         ] = Default(generate_unique_id),
     ) -> None:
-        if self.ignore_trailing_slash:
-            path = path.rstrip("/")
+        path = self._normalize_path(path)
         route_class = route_class_override or self.route_class
         responses = responses or {}
         combined_responses = {**self.responses, **responses}
@@ -1046,8 +1042,7 @@ class APIRouter(routing.Router):
         endpoint: Callable[..., Any],
         name: Optional[str] = None,
     ) -> None:
-        if self.ignore_trailing_slash:
-            path = path.rstrip("/")
+        path = self._normalize_path(path)
         super().add_websocket_route(path, endpoint, name)
 
     def add_api_websocket_route(
@@ -1058,8 +1053,7 @@ class APIRouter(routing.Router):
         *,
         dependencies: Optional[Sequence[params.Depends]] = None,
     ) -> None:
-        if self.ignore_trailing_slash:
-            path = path.rstrip("/")
+        path = self._normalize_path(path)
         current_dependencies = self.dependencies.copy()
         if dependencies:
             current_dependencies.extend(dependencies)
@@ -1143,8 +1137,7 @@ class APIRouter(routing.Router):
     def websocket_route(
         self, path: str, name: Union[str, None] = None
     ) -> Callable[[DecoratedCallable], DecoratedCallable]:
-        if self.ignore_trailing_slash:
-            path = path.rstrip("/")
+        path = self._normalize_path(path)
 
         def decorator(func: DecoratedCallable) -> DecoratedCallable:
             self.add_websocket_route(path, func, name=name)
@@ -1304,9 +1297,7 @@ class APIRouter(routing.Router):
             responses = {}
         for route in router.routes:
             if isinstance(route, APIRoute):
-                path = route.path
-                if self.ignore_trailing_slash:
-                    path = path.rstrip("/")
+                path = self._normalize_path(route.path)
                 combined_responses = {**responses, **route.responses}
                 use_response_class = get_value_or_default(
                     route.response_class,
@@ -1366,9 +1357,7 @@ class APIRouter(routing.Router):
                     generate_unique_id_function=current_generate_unique_id,
                 )
             elif isinstance(route, routing.Route):
-                path = route.path
-                if self.ignore_trailing_slash:
-                    path = path.rstrip("/")
+                path = self._normalize_path(route.path)
                 methods = list(route.methods or [])
                 self.add_route(
                     prefix + path,
@@ -1378,9 +1367,7 @@ class APIRouter(routing.Router):
                     name=route.name,
                 )
             elif isinstance(route, APIWebSocketRoute):
-                path = route.path
-                if self.ignore_trailing_slash:
-                    path = path.rstrip("/")
+                path = self._normalize_path(route.path)
                 current_dependencies = []
                 if dependencies:
                     current_dependencies.extend(dependencies)
@@ -1393,9 +1380,7 @@ class APIRouter(routing.Router):
                     name=route.name,
                 )
             elif isinstance(route, routing.WebSocketRoute):
-                path = route.path
-                if self.ignore_trailing_slash:
-                    path = path.rstrip("/")
+                path = self._normalize_path(route.path)
                 self.add_websocket_route(prefix + path, route.endpoint, name=route.name)
         for handler in router.on_startup:
             self.add_event_handler("startup", handler)
@@ -1406,6 +1391,11 @@ class APIRouter(routing.Router):
             router.lifespan_context,
         )
 
+    def _normalize_path(self, path: str) -> str:
+        if self.ignore_trailing_slash:
+            return path.rstrip("/")
+        return path
+
     def get(
         self,
         path: Annotated[