Add config option to skip Touchup step, for debugging purposes (#2361)

Co-authored-by: Adam Hopkins <adam@amhopkins.com>

sanic/app.py

@@ -1511,7 +1511,8 @@ class Sanic(BaseSanic, RunnerMixin, metaclass=TouchUpMeta):
             if not Sanic.test_mode:
                 raise e
 
-    def signalize(self):
+    def signalize(self, allow_fail_builtin=True):
+        self.signal_router.allow_fail_builtin = allow_fail_builtin
         try:
             self.signal_router.finalize()
         except FinalizationError as e:
@@ -1526,8 +1527,11 @@ class Sanic(BaseSanic, RunnerMixin, metaclass=TouchUpMeta):
         if hasattr(self, "_ext"):
             self.ext._display()
 
+        if self.state.is_debug:
+            self.config.TOUCHUP = False
+
         # Setup routers
-        self.signalize()
+        self.signalize(self.config.TOUCHUP)
         self.finalize()
 
         # TODO: Replace in v22.6 to check against apps in app registry
@@ -1547,6 +1551,7 @@ class Sanic(BaseSanic, RunnerMixin, metaclass=TouchUpMeta):
             # TODO:
             # - Raise warning if secondary apps have error handler config
             ErrorHandler.finalize(self.error_handler, config=self.config)
+            if self.config.TOUCHUP:
                 TouchUp.run(self)
 
         self.state.is_started = True

sanic/config.py

@@ -38,6 +38,7 @@ DEFAULT_CONFIG = {
     "REQUEST_MAX_SIZE": 100000000,  # 100 megabytes
     "REQUEST_TIMEOUT": 60,  # 60 seconds
     "RESPONSE_TIMEOUT": 60,  # 60 seconds
+    "TOUCHUP": True,
     "USE_UVLOOP": _default,
     "WEBSOCKET_MAX_SIZE": 2**20,  # 1 megabyte
     "WEBSOCKET_PING_INTERVAL": 20,
@@ -81,6 +82,7 @@ class Config(dict, metaclass=DescriptorMeta):
     REQUEST_TIMEOUT: int
     RESPONSE_TIMEOUT: int
     SERVER_NAME: str
+    TOUCHUP: bool
     USE_UVLOOP: Union[Default, bool]
     WEBSOCKET_MAX_SIZE: int
     WEBSOCKET_PING_INTERVAL: int

sanic/signals.py

@@ -80,6 +80,7 @@ class SignalRouter(BaseRouter):
             group_class=SignalGroup,
             stacking=True,
         )
+        self.allow_fail_builtin = True
         self.ctx.loop = None
 
     def get(  # type: ignore
@@ -129,7 +130,8 @@ class SignalRouter(BaseRouter):
         try:
             group, handlers, params = self.get(event, condition=condition)
         except NotFound as e:
-            if fail_not_found:
+            is_reserved = event.split(".", 1)[0] in RESERVED_NAMESPACES
+            if fail_not_found and (not is_reserved or self.allow_fail_builtin):
                 raise e
             else:
                 if self.ctx.app.debug and self.ctx.app.state.verbosity >= 1:

tests/test_touchup.py

@@ -2,6 +2,8 @@ import logging
 
 import pytest
 
+from sanic_routing.exceptions import NotFound
+
 from sanic.signals import RESERVED_NAMESPACES
 from sanic.touchup import TouchUp
 
@@ -28,3 +30,50 @@ async def test_ode_removes_dispatch_events(app, caplog, verbosity, result):
             )
             in logs
         ) is result
+
+
+@pytest.mark.parametrize("skip_it,result", ((False, True), (True, False)))
+async def test_skip_touchup(app, caplog, skip_it, result):
+    app.config.TOUCHUP = not skip_it
+    with caplog.at_level(logging.DEBUG, logger="sanic.root"):
+        app.state.verbosity = 2
+        await app._startup()
+    assert app.signal_router.allow_fail_builtin is (not skip_it)
+    logs = caplog.record_tuples
+
+    for signal in RESERVED_NAMESPACES["http"]:
+        assert (
+            (
+                "sanic.root",
+                logging.DEBUG,
+                f"Disabling event: {signal}",
+            )
+            in logs
+        ) is result
+    not_found_exceptions = 0
+    # Skip-touchup disables NotFound exceptions on the dispatcher
+    for signal in RESERVED_NAMESPACES["http"]:
+        try:
+            await app.dispatch(event=signal, inline=True)
+        except NotFound:
+            not_found_exceptions += 1
+    assert (not_found_exceptions > 0) is result
+
+
+@pytest.mark.parametrize("skip_it,result", ((False, True), (True, True)))
+async def test_skip_touchup_non_reserved(app, caplog, skip_it, result):
+    app.config.TOUCHUP = not skip_it
+
+    @app.signal("foo.bar.one")
+    def sync_signal(*_):
+        ...
+
+    await app._startup()
+    assert app.signal_router.allow_fail_builtin is (not skip_it)
+    not_found_exception = False
+    # Skip-touchup doesn't disable NotFound exceptions for user-defined signals
+    try:
+        await app.dispatch(event="foo.baz.two", inline=True)
+    except NotFound:
+        not_found_exception = True
+    assert not_found_exception is result