Rate-Limiter

A simple and reusable request rate-limiting microservice that protects external applications' endpoints.

Features

• Light-weight microservice which can be easily distributed and reused
• Stateless rate-limiting, where clients can choose specific configurations for time-windows, request limits, etc.
• gRPC access to the API, resulting in faster message transmissions and rigorous contracts
• Redis caching of user key-value records

Running Locally

Make sure you have Node.js, npm and Redis installed

  # Clone this repo by typing into your terminal
  $ git clone https://github.com/Justin-Kwan/Rate-Limiter
  
  # Change to directory containing index.js file
  $ cd Rate-Limiter/server/src
  
  # Start application
  $ node index.js

Testing Locally

  # Change to server directory
  $ cd Rate-Limiter/server
  
  # Start Redis server 
  $ redis-server
  
  # Run tests
  $ npm test

gRPC Api Access

Rate-Limiter provides gRPC access via an unary call. The service protocol buffer definitions are:

  # rate_limiter.proto

  service RateLimiter {
        rpc RateUserLimit (RateLimitRequest) returns (RateLimitResponse) {}
  }

  message RateLimitRequest {
        required string ipAddress = 1;
        required string requestedRoute = 2;
        required int64 requestedServiceId = 3;
        required int64 maxTokens = 4;
        required int64 requestWindow = 5; // time in seconds
  }

  message RateLimitResponse {
        required int64 maxTokens = 1;
        required int64 tokenCount = 2;
  }