@geekmidas/rate-limit

Rate limiting utilities with configurable windows and storage backends.

Installation

pnpm add @geekmidas/rate-limit

Features

• Configurable rate limiting with time windows
• Multiple storage backends (memory, cache)
• IP-based and custom identifier support
• Sliding window algorithm
• Integration with @geekmidas/constructs endpoints

Basic Usage

import { rateLimit } from '@geekmidas/rate-limit';
import { InMemoryCache } from '@geekmidas/cache/memory';

const limiter = rateLimit({
  limit: 100,          // Max requests
  windowMs: 60000,     // Time window in ms (1 minute)
  cache: new InMemoryCache(),
});

Usage with Endpoints

import { e } from '@geekmidas/constructs/endpoints';
import { rateLimit } from '@geekmidas/rate-limit';
import { InMemoryCache } from '@geekmidas/cache/memory';

const rateLimited = e
  .post('/api/messages')
  .rateLimit(rateLimit({
    limit: 10,
    windowMs: 60000,
    cache: new InMemoryCache(),
  }))
  .body(z.object({ content: z.string() }))
  .handle(async ({ body }) => ({ success: true }));

Configuration Options

Option	Type	Description
limit	number	Maximum number of requests in the window
windowMs	number	Time window in milliseconds
cache	Cache	Cache implementation for storing rate limit data
keyGenerator	(ctx) => string	Custom function to generate rate limit keys

Custom Key Generator

const limiter = rateLimit({
  limit: 100,
  windowMs: 60000,
  cache: new InMemoryCache(),
  keyGenerator: (ctx) => {
    // Rate limit by user ID instead of IP
    return ctx.session?.userId ?? ctx.ip;
  },
});

Production Usage

For production with distributed systems, use a shared cache:

import { UpstashCache } from '@geekmidas/cache/upstash';

const limiter = rateLimit({
  limit: 100,
  windowMs: 60000,
  cache: new UpstashCache({
    url: process.env.UPSTASH_REDIS_URL!,
    token: process.env.UPSTASH_REDIS_TOKEN!,
  }),
});