[Django] #35133: never_cache decorator problem with async get function inside classbased View

[Django]

#35133: never_cache decorator problem with async get function inside classbased
View
-------------------------------------+-------------------------------------
Reporter: | Owner: nobody
unnamedtrue |
Type: Bug | Status: new
Component: Core | Version: 5.0
(Cache system) | Keywords: never_cache,
Severity: Normal | decorator, async, classnased view,
Triage Stage: | dispatch, coroutine
Unreviewed | Has patch: 0
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
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If I use never_cache decorator for my classbased View I get this error:
"'coroutine' object has no attribute 'has_header'"
Code is:
{{{
@method_decorator(never_cache, name="dispatch")
class CheckAsync(View):
async def get(self, request, *args, **kwargs):
# Perform io-blocking view logic using await, sleep for example.
await asyncio.sleep(1)
return HttpResponse("Hello async world!")
}}}
Debug info:
{{{
Request Method: GET
Request URL: http://127.0.0.1:8000/api/asynccheck/

Django Version: 5.0.1
Python Version: 3.12.1
Installed Applications:
['core.apps.AdminConfig',
'django.contrib.sites',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'api.apps.ApiAppConfig',
]
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
'django.contrib.sites.middleware.CurrentSiteMiddleware',
'django.middleware.http.ConditionalGetMiddleware',
'django.middleware.gzip.GZipMiddleware']

Traceback (most recent call last):
File "/Users/me/p/lib/python3.12/site-
packages/django/core/handlers/exception.py", line 55, in inner
response = get_response(request)
^^^^^^^^^^^^^^^^^^^^^
File "/Users/me/p/lib/python3.12/site-
packages/django/core/handlers/base.py", line 197, in _get_response
response = wrapped_callback(request, *callback_args,
**callback_kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File
"/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/concurrent/futures/_base.py",
line 449, in result
return self.__get_result()
^^^^^^^^^^^^^^^^^^^
File
"/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/concurrent/futures/_base.py",
line 401, in __get_result
raise self._exception
^^^^^^^^^^^^^^^^^^^^^
File "/Users/me/p/lib/python3.12/site-
packages/django/views/generic/base.py", line 104, in view
return self.dispatch(request, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/me/p/lib/python3.12/site-
packages/django/utils/decorators.py", line 48, in _wrapper
return bound_method(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/me/p/lib/python3.12/site-
packages/django/views/decorators/cache.py", line 81, in _view_wrapper
add_never_cache_headers(response)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/me/p/lib/python3.12/site-packages/django/utils/cache.py",
line 292, in add_never_cache_headers
patch_response_headers(response, cache_timeout=-1)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/me/p/lib/python3.12/site-packages/django/utils/cache.py",
line 283, in patch_response_headers
if not response.has_header("Expires"):
^^^^^^^^^^^^^^^^^^^

Exception Type: AttributeError at /api/asynccheck/
Exception Value: 'coroutine' object has no attribute 'has_header'
}}}

--
Ticket URL: <https://code.djangoproject.com/ticket/35133>
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