Koa-simple-ratelimit NPM

koa-simple-ratelimit

Rate limiter middleware for koa v2. Differs from koa-ratelimit by not depending on ratelimiter and using redis ttl (time to live) to handle expiration time remaining. This creates only one entry in redis instead of the three that node-ratelimiter does.

Installation

npm install koa-simple-ratelimit

Example

import Koa from 'koa';
import redis from 'redis';

import { ratelimit } from 'koa-simple-ratelimit';

const app = new Koa();

// Apply rate limit

app.use(ratelimit({
	db: redis.createClient(),
	duration: 60000,
	max: 100
}));

// Response middleware

app.use((ctx, next) => {
	ctx.body = 'Stuff!';
	return next();
});

app.listen(4000);
console.log('listening on port http://localhost:4000');

Options

db redis connection instance
max max requests within duration 2500
duration of limit in milliseconds 3600000
id id to compare requests ip
allowlist array of ids to allowlist
blocklist array of ids to blocklist
prefix redis key prefix "limit"

Responses

Example 200 with header fields:

HTTP/1.1 200 OK
X-Powered-By: koa
X-RateLimit-Limit: 100
X-RateLimit-Remaining: 99
X-RateLimit-Reset: 1384377793
Content-Type: text/plain; charset=utf-8
Content-Length: 6
Date: Wed, 13 Nov 2013 21:22:13 GMT
Connection: keep-alive

Stuff!

Example 429 response:

HTTP/1.1 429 Too Many Requests
X-Powered-By: koa
X-RateLimit-Limit: 100
X-RateLimit-Remaining: 0
X-RateLimit-Reset: 1384377716
Content-Type: text/plain; charset=utf-8
Content-Length: 39
Retry-After: 7
Date: Wed, 13 Nov 2013 21:21:48 GMT
Connection: keep-alive

Rate limit exceeded, retry in 8 seconds