RateLimitJ

A Java library for rate limiting, assembled using extensible storage and application framework adaptors. The library's interfaces support thread-safe sync, async, and reactive usage patterns.

Modules

RateLimitJ provides the following stable plugable modules:

• Redis sliding window rate limiter
• In-memory sliding window rate limiter
• Dropwizard integration

Features

• Uses an efficient approximated sliding window algorithm for rate limiting
• Multiple limit rules per instance

Binaries/Download

Binaries and dependency information for Maven, Ivy, Gradle and others can be found at Maven Central.

Example for Maven:

<dependency>
  <groupId>es.moki.ratelimitj</groupId>
  <artifactId>ratelimitj-redis</artifactId>
  <version>${ratelimitj-redis.version}</version>
</dependency>

Prerequisite

• RateLimitJ requires Java 8

Roadmap

Feature	Status
Redis sliding window rate limiter	production
Dropwizard integration - Bundle	production
In-memory sliding window rate limiter	stable
In-memory concurrent rate limiter	beta
Rate limiting toggles (dark launch) for framework integration	beta
Hazelcast sliding window rate limiter	beta/dev
Redis concurrent rate limiter	dev/active
Enhanced metrics logging	back log
Whitelisting & blacklisting of keys	back log
Rate limit HTTP header responses	back log
Async in-memory rate limit buffer/cache (inspired by Google's SRE book)	back log
Spring integration	back log

Building

RateLimitJ is built with Gradle and requires docker to spin up Redis for the Redis module.

To build:

$ git clone https://github.com/mokies/ratelimitj.git
$ cd ratelimij/
$ ./gradlew

Credits

This library was inspired by the following articles on sliding window rate limiting with Redis:

• Introduction to Rate Limiting with Redis Part 1
• Introduction to Rate Limiting with Redis Part 2

Background Reading

• Stripe Blog - Scaling your API with rate limiters
• An alternative approach to rate limiting

Authors

• Craig Baker