id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
33495	"""Synchronous middleware ... adapted"" is not logged for synchronous middleware"	Aaron Chong	Aaron Chong	"This is a bug in log messages that contradicts the guide in a warning in the docs; the feature works.

The guide at https://docs.djangoproject.com/en/4.0/topics/async/#async-views, **emphasis** mine:

  Warning
  [[BR]]
  You will only get the benefits of a fully-asynchronous request stack if you have no synchronous middleware loaded into your site. **If there is a piece of synchronous middleware, then Django must use a thread per request to safely emulate a synchronous environment for it.**
  [[BR]]
  Middleware can be built to support both sync and async contexts. Some of Django’s middleware is built like this, but not all. **To see what middleware Django has to adapt, you can turn on debug logging for the django.request logger and look for log messages about “Synchronous middleware … adapted”.**

The test for ""Synchronous middleware ... adapted"" is instead testing an async middleware over a sync method: https://github.com/django/django/blob/7ca7f4495ba746279b734695a8dd137bf7ee0bab/tests/middleware_exceptions/tests.py#L222-L234

{{{#!python
@override_settings(MIDDLEWARE=[
    'middleware_exceptions.middleware.async_payment_middleware',
])
def test_async_middleware(self):
    with self.assertLogs('django.request', 'DEBUG') as cm:
        response = self.client.get('/middleware_exceptions/view/')
    self.assertEqual(response.status_code, 402)
    self.assertEqual(
        cm.records[0].getMessage(),
        ""Synchronous middleware ""
        ""middleware_exceptions.middleware.async_payment_middleware ""
        ""adapted."",
    )
}}}

About the existing implementation:

1. `BaseHandler.load_middleware` passes the middleware name as `name` to `BaseHandler.adapt_method_mode`: https://github.com/django/django/blob/98ad327864aed8df245fd19ea9d2743279e11643/django/core/handlers/base.py#L53-L57

{{{#!python
# Adapt handler, if needed.
adapted_handler = self.adapt_method_mode(
    middleware_is_async, handler, handler_is_async,
    debug=settings.DEBUG, name='middleware %s' % middleware_path,
)
}}}

2. `BaseHandler.adapt_method_mode` adapts the `method` and treats `name` as the method name rather than the middleware name; when the middleware name is used, it implies a method has been adapted for the middleware, not that the middleware was adapted:

{{{#!python
if debug and not name:
    name = name or 'method %s()' % method.__qualname__
if is_async:
    if not method_is_async:
        if debug:
            logger.debug('Synchronous %s adapted.', name)
        return sync_to_async(method, thread_sensitive=True)
elif method_is_async:
    if debug:
        logger.debug('Asynchronous %s adapted.', name)
    return async_to_sync(method)
}}}

Proposed fix:

Handle middleware `name` and method name separately within `BaseHandler.adapt_method_mode`:

{{{#!diff
  def adapt_method_mode(
      self, is_async, method, method_is_async=None, debug=False, name=None,
  ):
      """"""
      Adapt a method to be in the correct ""mode"":
      - If is_async is False:
        - Synchronous methods are left alone
        - Asynchronous methods are wrapped with async_to_sync
      - If is_async is True:
        - Synchronous methods are wrapped with sync_to_async()
        - Asynchronous methods are left alone
      """"""
+     method_name = None
      if method_is_async is None:
          method_is_async = asyncio.iscoroutinefunction(method)
      if debug and not name:
-         name = name or 'method %s()' % method.__qualname__
+         method_name = 'method %s()' % method.__qualname__
      if is_async:
          if not method_is_async:
              if debug:
-                 logger.debug('Synchronous %s adapted.', name)
+                 if name:
+                     logger.debug('Asynchronous %s adapted.', name)
+                 else:
+                     logger.debug('Synchronous %s adapted.', method_name)
              return sync_to_async(method, thread_sensitive=True)
      elif method_is_async:
          if debug:
-             logger.debug('Asynchronous %s adapted.', name)
+             if name:
+                 logger.debug('Synchronous %s adapted.', name)
+             else:
+                 logger.debug('Asynchronous %s adapted.', method_name)
          return async_to_sync(method)
}}}
"	Cleanup/optimization	closed	Core (Other)	4.0	Normal	fixed	async	Andrew Godwin	Ready for checkin	1	0	0	0	0	0