RateFlow 🛡️

A high-performance, zero-dependency rate-limiting library for Node.js and modern browsers. Built with TypeScript for type safety and predictability.

Features

• ⚡ Zero Dependencies: Lightweight and fast.
• 🔄 Multiple Algorithms:
  • Token Bucket: Handle conflicting traffic with burst allowances.
  • Leaky Bucket: Smooth out traffic spikes into a constant flow.
  • Sliding Window: Precise, time-based limiting without window boundary issues.
• 🟦 TypeScript Native: Full type definitions include.
• 🖥️ Dashboard Included: Visualize and debug your rate limits with the included interactive dashboard.

Installation

npm install @rateflow/core

Quick Start

import { RateFlow } from '@rateflow/core';

// Create a sliding window limiter
const limiter = RateFlow.create({
  type: 'sliding-window',
  options: {
    windowSizeInMs: 1000,
    maxRequests: 5
  }
});

// Use it
if (limiter.take()) {
  console.log("Request allowed");
} else {
  console.log("Rate limit exceeded");
}

Algorithms

Token Bucket

Ideal for bursty traffic. Allows a specified number of tokens to be used instantly, with tokens replenishing at a fixed rate.

Leaky Bucket

Maintains a constant outflow rate. Perfect for smoothing out traffic and ensuring a steady load on upstream services.

Sliding Window

The most precise approach. Prevents "edge cases" where traffic spikes occur at the boundary of a fixed window by tracking actual timestamps.

Dashboard

The project includes a premium dashboard for exploring the algorithms. To run it locally:

npm install
npm run dev:dashboard