rush 2018.12.1

A library for throttling algorithms

This library is intended to be a collection of algorithms that can be reused when throttling user interactions with a resource (e.g., an API).

This library is still a work in progress. See goals for what we’re striving for.

Installation

pip install rush

Goals

Below is the project’s list of goals broken down by category

Features

• A basic periodic interval rate limiter - N accesses per period of time. An example would be the GitHub API that limits authenticated users to 5,000 requests per hour.

• A leaky bucket rate limiter based off of the Generic Cell Ratelimiting Algorithm (a.k.a, GCRA).

• A Redis storage backend for rate limit results so that users can have state persisted across machines and application restarts.

• A Redis GCRA implementation, likely borrowed from Ruby’s redis-gcra gem.

Quality

• 100% test coverage

• Code auto-formatted by Black (CI will check if formatting wasn’t run prior to push)

• Commit messages following a uniform Kernel-like style

• Flake8, pylint, mypy, and bandit linting

• Complete type annotations

• Complete documentation linted by doclint and strictly compiled by Sphinx

Design

• Composable - ability to confidently use one algorithmic limiter with any properly written storage backend

• Easy to understand - hopefully it will be easy to understand how the library works because of how composable it will be