koa-simple-ratelimit

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

var ratelimit = require('koa-simple-ratelimit');
var redis = require('redis');
var koa = require('koa');
var app = new koa();

// apply rate limit

app.use(ratelimit({
  db: redis.createClient(),
  duration: 60000,
  max: 100,
  id: function (ctx) {
    return ctx.ip;
  },
  blacklist: [],
  whitelist: []
}));

// response middleware

app.use(function (ctx){
  ctx.body = 'Hello';
});

app.listen(3000);
console.log('listening on port 3000');

Options

• db redis connection instance
• max max requests within duration [2500]
• duration of limit in milliseconds [3600000]
• id id to compare requests [ip]
• whitelist array of ids to whitelist
• blacklist array of ids to blacklist

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

License

MIT