StaticCachedS3BotoStorage - that reads its manifest.json locally

storage.py

from django.conf import settings
from django.core.files.storage import get_storage_class

from compressor.cache import get_offline_manifest_filename
from storages.backends.s3boto import S3BotoStorage


class StaticCachedS3BotoStorage(S3BotoStorage):
    """
    S3 storage backend that also saves files locally for django-compressor
    and also reads the manifest file from the local file-system instead of
    S3, so packaged deploys also point to their own manifest.
    """
    bucket_name = settings.AWS_BUCKET_NAME_STATIC
    # reduced_redundancy = True
    # headers = {
    #     'Cache-Control': 'max-age=2592000',
    # }

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.local_storage = get_storage_class(
            'compressor.storage.CompressorFileStorage'
        )()
        self.offline_manifest_filename = get_offline_manifest_filename()

    def save(self, name, content):
        name = super().save(name, content)
        self.local_storage._save(name, content)
        return name

    def _is_manifest(self, name):
        return self._normalize_name(self._clean_name(name)) == self.offline_manifest_filename

    def exists(self, name):
        if self._is_manifest(name):
            return self.local_storage.exists(name)
        else:
            return super().exists(name)

    def _open(self, name, mode='rb'):
        if self._is_manifest(name):
            return self.local_storage._open(name, mode)
        else:
            return super()._open(name, mode)