remove resolve_signature_namespace

litestar/handlers/base.py

@@ -55,7 +55,6 @@ class BaseRouteHandler:
         "_resolved_data_dto",
         "_parameter_field_definitions",
         "_resolved_return_dto",
-        "_resolved_signature_namespace",
         "_resolved_signature_model",
         "_registered",
         "dependencies",
@@ -128,7 +127,6 @@ def __init__(
         self._resolved_data_dto: type[AbstractDTO] | None | EmptyType = Empty
         self._parameter_field_definitions: dict[str, FieldDefinition] | EmptyType = Empty
         self._resolved_return_dto: type[AbstractDTO] | None | EmptyType = Empty
-        self._resolved_signature_namespace: dict[str, Any] | EmptyType = Empty
         self._resolved_signature_model: type[SignatureModel] | EmptyType = Empty
         self._registered = False
 
@@ -171,7 +169,7 @@ def merge(self, other: Controller | Router) -> Self:
             middleware=[*(other.middleware or ()), *self.middleware],
             name=self.name,
             opt={**other.opt, **self.opt},
-            signature_namespace={**other.signature_namespace, **self.signature_namespace},
+            signature_namespace=merge_signature_namespaces(other.signature_namespace, self.signature_namespace),
             signature_types=other.signature_types,
             type_decoders=(*(other.type_decoders or ()), *self.type_decoders),
             type_encoders={**(other.type_encoders or {}), **self.type_encoders},
@@ -234,9 +232,7 @@ def parsed_fn_signature(self) -> ParsedSignature:
             A ParsedSignature instance
         """
         if self._parsed_fn_signature is Empty:
-            self._parsed_fn_signature = ParsedSignature.from_fn(
-                unwrap_partial(self.fn), self._resolve_signature_namespace()
-            )
+            self._parsed_fn_signature = ParsedSignature.from_fn(unwrap_partial(self.fn), self.signature_namespace)
 
         return self._parsed_fn_signature
 
@@ -358,9 +354,7 @@ def _finalize_dependencies(self, app: Litestar | None = None):
                     signature, init_type_hints = plugin.get_typed_init(dependency)
                     provider.parsed_fn_signature = ParsedSignature.from_signature(signature, init_type_hints)
                 else:
-                    provider.parsed_fn_signature = ParsedSignature.from_fn(
-                        dependency, self._resolve_signature_namespace()
-                    )
+                    provider.parsed_fn_signature = ParsedSignature.from_fn(dependency, self.signature_namespace)
 
             if not getattr(provider, "signature_model", None):
                 provider.signature_model = SignatureModel.create(
@@ -387,20 +381,11 @@ def resolve_exception_handlers(self) -> ExceptionHandlersMap:
         self._check_registered()
         return self.exception_handlers
 
-    def _resolve_signature_namespace(self) -> dict[str, Any]:
-        """Build the route handler signature namespace dictionary by going from top to bottom.
-
-        When merging keys from multiple layers, if the same key is defined by multiple layers, the value from the
-        layer closest to the response handler will take precedence.
-        """
-        if self._resolved_signature_namespace is Empty:
-            ns: dict[str, Any] = {}
-            for layer in self._ownership_layers:
-                merge_signature_namespaces(
-                    signature_namespace=ns, additional_signature_namespace=layer.signature_namespace
-                )
-            self._resolved_signature_namespace = ns
-        return self._resolved_signature_namespace
+    @deprecated("3.0", removal_in="4.0", alternative=".signature_namespace attribute")
+    def resolve_signature_namespace(self) -> dict[str, Any]:
+        """Build the route handler signature namespace dictionary by going from top to bottom"""
+        self._check_registered()
+        return self.signature_namespace
 
     def resolve_data_dto(self, app: Litestar | None = None) -> type[AbstractDTO] | None:
         """Resolve the data_dto by starting from the route handler and moving up.

litestar/handlers/http_handlers/base.py

@@ -60,6 +60,7 @@
 from litestar.utils.predicates import is_async_callable
 from litestar.utils.predicates import is_class_and_subclass
 from litestar.utils.scope.state import ScopeState
+from litestar.utils.signature import merge_signature_namespaces
 from litestar.utils.warnings import warn_implicit_sync_to_thread, warn_sync_to_thread_with_async_callable
 
 if TYPE_CHECKING:
@@ -389,7 +390,7 @@ def merge(self, other: Controller | Router) -> HTTPRouteHandler:
             middleware=[*(other.middleware or ()), *self.middleware],
             name=self.name,
             opt={**(other.opt or {}), **(self.opt or {})},
-            signature_namespace={**other.signature_namespace, **self.signature_namespace},
+            signature_namespace=merge_signature_namespaces(other.signature_namespace, self.signature_namespace),
             # signature_types=getattr(other, "signature_types", None),
             type_decoders=(*(other.type_decoders or ()), *self.type_decoders),
             type_encoders={**(other.type_encoders or {}), **self.type_encoders},

litestar/handlers/websocket_handlers/listener.py

@@ -27,7 +27,7 @@
     TypeEncodersMap,
 )
 from litestar.utils import ensure_async_callable, join_paths
-from litestar.utils.signature import ParsedSignature, get_fn_type_hints
+from litestar.utils.signature import ParsedSignature, get_fn_type_hints, merge_signature_namespaces
 
 from ._utils import (
     ListenerHandler,
@@ -247,7 +247,7 @@ def merge(self, other: Controller | Router) -> WebsocketListenerRouteHandler:
             middleware=[*(other.middleware or ()), *self.middleware],
             name=self.name,
             opt={**(other.opt or {}), **(self.opt or {})},
-            signature_namespace={**other.signature_namespace, **self.signature_namespace},
+            signature_namespace=merge_signature_namespaces(other.signature_namespace, self.signature_namespace),
             signature_types=getattr(other, "signature_types", None),
             type_decoders=(*(other.type_decoders or ()), *self.type_decoders),
             type_encoders={**(other.type_encoders or {}), **self.type_encoders},
@@ -266,7 +266,7 @@ def on_registration(self, route: BaseRoute, app: Litestar) -> None:
         super().on_registration(route, app)
 
     def _prepare_fn(self) -> ListenerHandler:
-        parsed_signature = ParsedSignature.from_fn(self.fn, self._resolve_signature_namespace())
+        parsed_signature = ParsedSignature.from_fn(self.fn, self.signature_namespace)
 
         if "data" not in parsed_signature.parameters:
             raise ImproperlyConfiguredException("Websocket listeners must accept a 'data' parameter")
@@ -282,13 +282,13 @@ def _prepare_fn(self) -> ListenerHandler:
         self._parsed_fn_signature = ParsedSignature.from_signature(
             create_handler_signature(parsed_signature.original_signature),
             fn_type_hints={
-                **get_fn_type_hints(self.fn, namespace=self._resolve_signature_namespace()),
-                **get_fn_type_hints(ListenerHandler.__call__, namespace=self._resolve_signature_namespace()),
+                **get_fn_type_hints(self.fn, namespace=self.signature_namespace),
+                **get_fn_type_hints(ListenerHandler.__call__, namespace=self.signature_namespace),
             },
         )
 
         return ListenerHandler(
-            listener=self, fn=self.fn, parsed_signature=parsed_signature, namespace=self._resolve_signature_namespace()
+            listener=self, fn=self.fn, parsed_signature=parsed_signature, namespace=self.signature_namespace
         )
 
     def _validate_handler_function(self, app: Litestar | None = None) -> None:

litestar/handlers/websocket_handlers/route_handler.py

@@ -13,6 +13,7 @@
 from litestar.utils import join_paths
 from litestar.utils.empty import value_or_default
 from litestar.utils.predicates import is_async_callable
+from litestar.utils.signature import merge_signature_namespaces
 
 if TYPE_CHECKING:
     from litestar import Controller, Router, Litestar
@@ -92,7 +93,7 @@ def merge(self, other: Controller | Router) -> WebsocketRouteHandler:
             middleware=[*(other.middleware or ()), *self.middleware],
             name=self.name,
             opt={**(other.opt or {}), **(self.opt or {})},
-            signature_namespace={**other.signature_namespace, **self.signature_namespace},
+            signature_namespace=merge_signature_namespaces(other.signature_namespace, self.signature_namespace),
             signature_types=getattr(other, "signature_types", None),
             type_decoders=(*(other.type_decoders or ()), *self.type_decoders),
             type_encoders={**(other.type_encoders or {}), **self.type_encoders},

litestar/handlers/websocket_handlers/stream.py

@@ -218,7 +218,7 @@ def on_registration(self, route: BaseRoute, app: Litestar) -> None:
         self._ws_stream_options = self.opt["stream_options"]
 
         parsed_handler_signature = parsed_stream_fn_signature = ParsedSignature.from_fn(
-            self.fn, self._resolve_signature_namespace()
+            self.fn, self.signature_namespace
         )
 
         if not parsed_stream_fn_signature.return_type.is_subclass_of(AsyncGenerator):