Django can't find staticfiles with Debug=False

Question

Hi all I'm having trouble solving this issue: If I turn DEBUG to False, I can't run manage.py runserver:

CommandError: You must set settings.ALLOWED_HOSTS if DEBUG is False

Then, let's say I add something to ALLOWED_HOSTS:

ALLOWED_HOSTS = ['*']
or
ALLOWED_HOSTS = ['localhost']
or
ALLOWED_HOSTS = ['127.0.0.1', 'localhost']

Now, I can do ´manage.py runserver´ but the staticfiles don't work. Weird.

If I turn DEBUG to True, then it works with ALLOWED_HOSTS set to nothing, to localhost or to *. So, I guess the problem has to do with DEBUG. I don't understand it.

Answer 1

In DEBUG mode, the Django development server handles serving static files for you. However, this is not best for production as it's much more inefficient than a true server. See here.

Serving the files

In addition to these configuration steps, you’ll also need to actually serve the static files.

During development, if you use django.contrib.staticfiles, this will be done automatically by runserver when DEBUG is set to True (see django.contrib.staticfiles.views.serve()).

This method is grossly inefficient and probably insecure, so it is unsuitable for production.

See Deploying static files for proper strategies to serve static files in production environments.

Check out here to learn out how to serve static files in production.

EDIT: Adding the following to answer @alejoss question about viewing error pages with DEBUG=True.

I added something like the following to my root urls.py file:

if settings.DEBUG:
    urlpatterns += patterns(
        '',
        url(r'^400/$', TemplateView.as_view(template_name='400.html')),
        url(r'^403/$', TemplateView.as_view(template_name='403.html')),
        url(r'^404/$', 'django.views.defaults.page_not_found'),
        url(r'^500/$', 'django.views.defaults.server_error'),
    )

You might need to alter a bit (i.e., the 400 and 403 pages may need to be edited if your template names are different). Basically, this lets you visit http://localhost/400 to see your 400 error page, http://localhost/403 to see your 403 error page, and so on.

Answer 2

Okay Here's the very clean solution. you need to use

DEBUG = False
DEBUG_PROPAGATE_EXCEPTIONS = True

This way in your logs you can see what is then problem. Whitenoise returns 500 usually when It is missing some file.

You can see what is missing in you logs. In my case heroku logs were enough.

for more info: https://docs.djangoproject.com/en/2.0/ref/settings/#debug-propagate-exceptions

Answer 3

If you still need to server static locally (e.g. for testing without debug) you can run devserver in insecure mode:

manage.py runserver --insecure