Add setting to exclude directories from STATIC_ROOT

[svleeuwen]

This allows to exclude e.g. the /admin/ directory which is not required in the static site.

See also #107.

[palewire]

I wonder if there's way to handle this upstream of bakery. Could you remove it from our INSTALLED_APPS? Or change your staticfiles configuration elsewhere in your settings?

[palewire]

I am closing this PR pending a response to my question above.

[svleeuwen]

I forgot about this PR. To answer your question:

Removing django.contrib.admin from INSTALLED_APPS does work. You could add the removal to a separate settings file and use python manage.py build --settings=config.settings.bakery. I don't think this is very user friendly though.

Also, when running a build, this will exclude the directory from the STATIC_ROOT (because build runs collectstatic), which can result in unwanted side effects. (this PR only excludes from the bakery build, after collectstatic has been run)

Finally, this doesn't work for e.g. wagtail.* apps. Removing those results in errors like:
RuntimeError: Model class wagtail.users.models.UserProfile doesn't declare an explicit app_label and isn't in an application in INSTALLED_APPS. when building.

[palewire]

Reopening for discussion. Is there a use case here beyond the admin app? I wonder if we might be better off tailoring a fix specifically for the admin, though I'm not fully swayed that this static file deployment of admin files is a very big deal.

[coveralls]

Coverage increased (+0.6%) to 80.415% when pulling 82a7046 on svleeuwen:master into 18bbb24 on datadesk:master.

[svleeuwen]

Is there a use case here beyond the admin app?

I think using wagtail (or any other CMS that includes it's own static files) is a reasonable use case. Currently these folders are included in the bakery output:

wagtailadmin/
wagtaildocs/
wagtailembeds/
wagtailimages/
wagtailmedia/
wagtailmenus/
wagtailmodeladmin/
wagtailsettings/
wagtailsnippets/
wagtailusers/

So, in my project I'm using:

BAKERY_STATIC_EXCLUDE_DIRS = [
    'admin',
    'wagtail*',
]

More people are having this issue, hence this related issue in wagtail-bakery.

[palewire]

Could we solve this further upstream with how we handle collectstatic's configuration, rather than having them be collected only to be clobbered?