Minor Feature Request: Unconfigured Allowed_Hosts Setting Should Raise ImproperlyConfigured Error

[Robert Roskam]

I realize this is a simple thing, but I'm sure this will save some people time.

Since Allowed_Hosts is a required setting, when debug mode is off, it should raise an appropriate ImproperlyConfigured error.

I'm sure there's some broader discussion surrounding which settings should have this and why, but I haven't been able to find it.

Robert

[Carl Meyer]

This makes sense - a configuration with DEBUG=False and empty
ALLOWED_HOSTS can't possibly work, so why should we even allow it to
start up? Can anyone else recall a reason why we didn't do this?

Carl

[Tim Graham]

We added such a check in runserver [1]. For other servers it seems less clear to me where that check would go -- in the WSGI handler? In django.setup()? (obviously, there is no need for ALLOWED_HOSTS if you are using Django outside a webserver context, so the check could be annoying if it's there).

[1] https://code.djangoproject.com/ticket/19875

[Carl Meyer]

On 06/10/2015 11:55 AM, Tim Graham wrote:
> We added such a check in runserver [1].

Unfortunately, this doesn't help for the (likely) most common case of
"local dev with runserver and DEBUG=True, deployment with another server
and DEBUG=False".

> For other servers it seems less
> clear to me where that check would go -- in the WSGI handler? In
> django.setup()?

I was thinking django.setup() or directly in django.conf.settings.

> (obviously, there is no need for ALLOWED_HOSTS if you
> are using Django outside a webserver context, so the check could be
> annoying if it's there).

Yes, this is true. I guess we have to weigh the debugging issues caused
by not having such a check against the (rare?) case of someone running
Django in a non-request-serving capacity with a different settings file
from the one they use to serve requests. (It's that latter clause that
makes it seem a rare case to me - normally when you run e.g. Celery or
some other type of worker process, you'd want to run it with exactly the
same settings as your request-serving processes, in order to avoid other
inconsistencies causing problems.)

And the workaround for the annoying case would be simple - just go ahead
and configure ALLOWED_HOSTS to something non-empty, even though you
technically don't need it.

Carl

> [1] https://code.djangoproject.com/ticket/19875
>
> On Wednesday, June 10, 2015 at 1:40:11 PM UTC-4, Carl Meyer wrote:
>
> On 06/10/2015 09:55 AM, Robert Roskam wrote:
> > I realize this is a simple thing, but I'm sure this will save some
> > people time.
> >
> > Since Allowed_Hosts is a required setting, when debug mode is off, it
> > should raise an appropriate ImproperlyConfigured error.
> >
> > I'm sure there's some broader discussion surrounding which settings
> > should have this and why, but I haven't been able to find it.
>
> This makes sense - a configuration with DEBUG=False and empty
> ALLOWED_HOSTS can't possibly work, so why should we even allow it to
> start up? Can anyone else recall a reason why we didn't do this?
>
> Carl
>

> --
> You received this message because you are subscribed to the Google
> Groups "Django developers (Contributions to Django itself)" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to django-develop...@googlegroups.com
> <mailto:django-develop...@googlegroups.com>.
> To post to this group, send email to django-d...@googlegroups.com
> <mailto:django-d...@googlegroups.com>.
> Visit this group at http://groups.google.com/group/django-developers.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/django-developers/c4af417b-4775-4fda-90ad-f6bf2c93f9b2%40googlegroups.com
> <https://groups.google.com/d/msgid/django-developers/c4af417b-4775-4fda-90ad-f6bf2c93f9b2%40googlegroups.com?utm_medium=email&utm_source=footer>.
> For more options, visit https://groups.google.com/d/optout.

[Tim Graham]

I forgot about the existing settings checks in django.conf__init__.py. That seems like a reasonable place.

Robert do you want to try to write a patch and/or open a ticket?

> <mailto:django-developers+unsub...@googlegroups.com>.

[Robert Roskam]

I'll give it a shot. First day here in the group, so wasn't sure of the procedures.