Skip to main content

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

Project description

Rehash is a resumable interface to the OpenSSL-based hashers (message digest objects) in the CPython hashlib standard library. Rehash provides hashers that can be pickled, persisted and 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()

Installation

pip install rehash

Applications

Rehash is useful in any situation when your VM is short-lived or preemptable, and the object you’re hashing is huge. For example, Rehash can be used to hand off the hashing state of large objects between AWS Lambda functions or Google Cloud Functions, which have runtime limits of 15 and 9 minutes, respectively.

License

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

https://travis-ci.org/kislyuk/rehash.png https://codecov.io/github/kislyuk/rehash/coverage.svg?branch=master https://img.shields.io/pypi/v/rehash.svg https://img.shields.io/pypi/l/rehash.svg https://readthedocs.org/projects/rehash/badge/?version=latest

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

rehash-1.0.0.tar.gz (5.0 kB view hashes)

Uploaded Source

Built Distribution

rehash-1.0.0-py2.py3-none-any.whl (8.7 kB view hashes)

Uploaded Python 2 Python 3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page