Move __setattr__ for __fake_slots__ check into base calss

sanic/app.py

@@ -33,7 +33,6 @@
     Union,
 )
 from urllib.parse import urlencode, urlunparse
-from warnings import warn
 
 from sanic_routing.exceptions import FinalizationError  # type: ignore
 from sanic_routing.exceptions import NotFound  # type: ignore
@@ -185,18 +184,6 @@ def __init__(
         if dumps:
             BaseHTTPResponse._dumps = dumps
 
-    def __setattr__(self, name: str, value: Any) -> None:
-        # This is a temporary compat layer so we can raise a warning until
-        # setting attributes on the app instance can be removed and deprecated
-        # with a proper implementation of __slots__
-        if name not in self.__fake_slots__:
-            warn(
-                "Setting variables on application instances is deprecated and "
-                "will be removed in version 21.9. You should change your "
-                f"application to use app.ctx.{name} instead."
-            )
-        super().__setattr__(name, value)
-
     @property
     def loop(self):
         """

sanic/base.py

@@ -1,3 +1,6 @@
+from typing import Any, Tuple
+from warnings import warn
+
 from sanic.mixins.exceptions import ExceptionMixin
 from sanic.mixins.listeners import ListenerMixin
 from sanic.mixins.middleware import MiddlewareMixin
@@ -35,8 +38,23 @@ class BaseSanic(
     SignalMixin,
     metaclass=Base,
 ):
+    __fake_slots__: Tuple[str, ...]
+
     def __str__(self) -> str:
         return f"<{self.__class__.__name__} {self.name}>"
 
     def __repr__(self) -> str:
         return f'{self.__class__.__name__}(name="{self.name}")'
+
+    def __setattr__(self, name: str, value: Any) -> None:
+        # This is a temporary compat layer so we can raise a warning until
+        # setting attributes on the app instance can be removed and deprecated
+        # with a proper implementation of __slots__
+        if name not in self.__fake_slots__:
+            warn(
+                f"Setting variables on {self.__class__.__name__} instances is "
+                "deprecated and will be removed in version 21.9. You should "
+                f"change your {self.__class__.__name__} instance to use "
+                f"instance.ctx.{name} instead."
+            )
+        super().__setattr__(name, value)

sanic/blueprints.py

@@ -4,17 +4,7 @@
 
 from collections import defaultdict
 from types import SimpleNamespace
-from typing import (
-    TYPE_CHECKING,
-    Any,
-    Dict,
-    Iterable,
-    List,
-    Optional,
-    Set,
-    Union,
-)
-from warnings import warn
+from typing import TYPE_CHECKING, Dict, Iterable, List, Optional, Set, Union
 
 from sanic_routing.exceptions import NotFound  # type: ignore
 from sanic_routing.route import Route  # type: ignore
@@ -115,18 +105,6 @@ def __repr__(self) -> str:
         )
         return f"Blueprint({args})"
 
-    def __setattr__(self, name: str, value: Any) -> None:
-        # This is a temporary compat layer so we can raise a warning until
-        # setting attributes on the app instance can be removed and deprecated
-        # with a proper implementation of __slots__
-        if name not in self.__fake_slots__:
-            warn(
-                "Setting variables on blueprint instances is deprecated and "
-                "will be removed in version 21.9. You should change your "
-                f"blueprint to use bp.ctx.{name} instead."
-            )
-        super().__setattr__(name, value)
-
     @property
     def apps(self):
         if not self._apps:

tests/test_app.py

@@ -380,9 +380,9 @@ def test_app_set_attribute_warning(app):
 
     assert len(record) == 1
     assert record[0].message.args[0] == (
-        "Setting variables on application instances is deprecated "
+        "Setting variables on Sanic instances is deprecated "
         "and will be removed in version 21.9. You should change your "
-        "application to use app.ctx.foo instead."
+        "Sanic instance to use instance.ctx.foo instead."
     )
 
 

tests/test_blueprints.py

@@ -1033,7 +1033,7 @@ def test_bp_set_attribute_warning():
 
     assert len(record) == 1
     assert record[0].message.args[0] == (
-        "Setting variables on blueprint instances is deprecated "
+        "Setting variables on Blueprint instances is deprecated "
         "and will be removed in version 21.9. You should change your "
-        "blueprint to use bp.ctx.foo instead."
+        "Blueprint instance to use instance.ctx.foo instead."
     )