Using django-storages to put MEDIA in S3, STATICFILES in Cloudfront

aws_storages.py

from django.conf import settings
from storages.backends.s3boto import S3BotoStorage


class UserMediaS3Storage(S3BotoStorage):
    def __init__(self, *args, **kwargs):
        # if we set settings.AWS_S3_BUCKET, it will interfere with storagres.backends.s3boto.S3BotoStorage
        #   rendering of our {% static %} assets. So, we're leaving that unset and getting our bucket from
        #   another settings var.
        kwargs['bucket'] = getattr(settings, 'USER_MEDIA_STORAGE_BUCKET')

        # We had to set AWS_S3_CUSTOM_DOMAIN for CloudFront to work with {% static %} tags. However, this
        #   interferes with rendering the url for a FileField on an object. We'll unset it now so that the
        #   default behavior returns.
        kwargs['custom_domain'] = None
        
        super(UserMediaS3Storage, self).__init__(*args, **kwargs)

settings.py

# [ ... snip ... ]

AWS_ACCESS_KEY_ID = 'FOO'               # 
AWS_SECRET_ACCESS_KEY = 'BAR'           # 
AWS_S3_CUSTOM_DOMAIN = ''               # ... your cloudfront domain
USER_MEDIA_STORAGE_BUCKET = ''          # ... the S3 bucket for user uploads
DEFAULT_FILE_STORAGE = 'aws_storages.UserMediaS3Storage'
STATICFILES_STORAGE = 'storages.backends.s3boto.S3BotoStorage'

# [ ... snip ... ]