django-pzip-storage

A FileSystemStorage subclass for Django that encrypts/compresses with PZip.

Installation

pip install django-pzip-storage

Usage

The simplest way to use PZipStorage is by setting your DEFAULT_FILE_STORAGE to pzip_storage.PZipStorage. By default, PZipStorage will use your SECRET_KEY setting as the encryption key.

IMPORTANT: Encrypting with SECRET_KEY means you must keep SECRET_KEY a secret, and if you lose or reset it without first rotating the keys of all stored files, they will be lost forever.

PZipStorage may be used with existing unencrypted files, as a drop-in replacement for FileSystemStorage. If it determines the requested file is not a PZip file, it will delegate to FileSystemStorage after emitting a needs_encryption signal (see below).

You may also use PZipStorage as a custom storage backend anywhere Django allows it; see Managing Files in the Django documentation for more information.

Settings

• PZIP_STORAGE_EXTENSION - the extension to append to any file saved with PZipStorage. Defaults to .pz.
• PZIP_STORAGE_NOCOMPRESS - a set of file extensions (with leading period) which should not be compressed when saving. See PZipStorage.DEFAULT_NOCOMPRESS for the default list.
• PZIP_STORAGE_KEYS - an iterable (or callable returning an iterable) of keys to use. The first key on the list will be used for encrypting files. Defaults to PZipStorage.default_keys, which yields SECRET_KEY.

These settings may be overridden on a per-storage basis by instantiating PZipStorage manually with extension or nocompress keyword arguments.

Signals

PZipStorage emits a number of signals when opening files in various circumstances:

• pzip_storage.needs_rotation - sent when a file was decrypted using an old key, i.e. not the first key in the provided list.
• pzip_storage.needs_encryption - sent when an unencrypted file was opened.
• pzip_storage.bad_keys - sent when an encrypted file was opened, but no keys in the list could decrypt it.

You may listen for these signals to do things like gradual encryption, key rotation, or logging.