Rate limiter middleware backed by lru-cache
npm install koa-ratelimit-lruRate limiter middleware backed by lru-cache for koa@2
Middleware using async/await , so you have to run in Node.js >= 7.0.0 with --harmony_async_await or using babel
``js`
$ npm install koa-ratelimit-lru
`js
const ratelimit = require('koa-ratelimit-lru')
const Koa = require('koa')
const app = new Koa()
// apply rate limit
app.use(ratelimit({
duration: 60000,
rate: 100,
id (ctx) {
return ctx.ip
},
headers: {
remaining: 'Rate-Limit-Remaining',
reset: 'Rate-Limit-Reset',
total: 'Rate-Limit-Total'
},
errorMessage: 'Sometimes You Just Have to Slow Down.'
}))
// response middleware
app.use(ctx => {
ctx.body = 'Hello World'
})
app.listen(3000, _ => console.log('listening on port 3000'))
`
Using one lru-cache to store keys
`javascript
const ratelimit = require('koa-ratelimit-lru')
const Koa = require('koa')
const router = require('koa-router')()
const app = new Koa()
const store = require('lru-cache')()
// Note: When you using custom store, duration and max would lose efficacy
router.get(
'/foo',
ratelimit({
store,
rate: 5,
prefix: 'foo:'
}),
ctx => ctx.body = 'foo'
)
router.get(
'/bar',
ratelimit({
store,
rate: 10,
prefix: 'bar:'
}),
ctx => ctx.body = 'bar'
)
// response middleware
app.use(router.routes())
app.listen(3000, _ => console.log('listening on port 3000'))
`
* duration limit duration in milliseconds [1 minute]max
* max length of cache [Infinity]store
* custom lru-cache [new cache]prefix
* custom prefix in lru-cache [ratelimit:]rate
* max requests per id [1000]id
* id to compare requests [ip]body
* custom throw body [json]headers
* custom header namesremaining
* remaining number of requests ['X-RateLimit-Remaining']reset
* reset timestamp ['X-RateLimit-Reset']total
* total number of requests ['X-RateLimit-Limit']
Example 200 with header fields:
`
HTTP/1.1 200 OK
X-RateLimit-Limit: 100
X-RateLimit-Remaining: 99
X-RateLimit-Reset: 1477978284
Content-Type: text/plain; charset=utf-8
Content-Length: 12
Date: Tue, 01 Nov 2016 05:13:11 GMT
Connection: keep-alive
Stuff!
`
Example 429 response:
`
HTTP/1.1 429 Too Many Requests
X-RateLimit-Remaining: 0
X-RateLimit-Reset: 1477978284
X-RateLimit-Limit: 100
Retry-After: 2
Content-Type: application/json; charset=utf-8
Content-Length: 50
Date: Tue, 01 Nov 2016 05:31:21 GMT
Connection: keep-alive
{"msg":"Rate limit exceeded, retry in 3 seconds."}
``
MIT