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
34174	async process_exception being called as sync from async view/middleware	Gabriel Rado	nobody	"following this bold part of the docs[https://docs.djangoproject.com/en/4.1/topics/http/middleware/#asynchronous-support]:


process_view, process_template_response and process_exception methods, if they are provided, **should also be adapted to match the sync/async mode**. However, Django will individually adapt them as required if you do not, at an additional performance penalty.

I' using this middleware to parse errors from sync and async views:


{{{
@sync_and_async_middleware
def custom_error(get_response):
    if asyncio.iscoroutinefunction(get_response):

        async def middleware(request):
            response = await get_response(request)
            return response

        async def _process_exception(request, exception):
            return my_custom_process_exception(exception)

    else:

        def middleware(request):
            response = get_response(request)
            return response

        def _process_exception(request, exception):
            return my_custom_process_exception(exception)

    middleware.process_exception = _process_exception
    return middleware
}}}

and I'm getting ""ValueError: The view my_view.view_func didn't return an HttpResponse object. It returned an unawaited coroutine instead. You may need to add an 'await' into your view."" from here[https://github.com/django/django/blob/main/django/core/handlers/base.py#L257]

i thought that with an async middleware + async view, all my hooks (process_view, process_template_response and process_exception) should be also async, but it appears that is mandatory to use sync process_exception with async capable middlewares. if this is intended, could the official docs be changed to expose this mandatory behavior?"	Cleanup/optimization	new	Documentation	4.1	Normal		middleware async process_exception		Unreviewed	0	0	0	0	0	0