rehash 0.1.0

Resumable hashlib: a picklable interface to CPython's OpenSSL-based hashlib standard library

Rehash is a resumable interface to the OpenSSL-based hashers in the CPython hashlib standard library. Rehash provides hashers that can be pickled, reconstituted from their repr(), and otherwise serialized. The rest of the Rehash API is identical to hashlib.

Rehash hashers can be used to checkpoint and restore progress when hashing large byte streams:

import pickle, rehash
hasher = rehash.sha256(b"foo")
state = pickle.dumps(hasher)

hasher2 = pickle.loads(state)
hasher2.update(b"bar")

assert hasher2.hexdigest() == rehash.sha256(b"foobar").hexdigest()

Non-openssl hashers

sha3 and blake2 hash algorithms in Python 3.6 are not OpenSSL-based and not supported by rehash.

PyPy

PyPy uses its own hasher implementations. Those are not serializable using rehash.

Links

• Project home page (GitHub)

• Documentation (Read the Docs)

• Package distribution (PyPI)

• Change log

Bugs

Please report bugs, issues, feature requests, etc. on GitHub.

License

Licensed under the terms of the Apache License, Version 2.0.