dsewnr / dcard-take-home-test

A rate limiter in Golang

Take Home Test for Web Backend Developer

How it works

Set environment variable and run server.

$ export GO111MODULE=on
$ npm start

Open browser with http://localhost:8080/

Test

# test server
$ go test -v 

# test request handler
$ go test -v reqholder 

Set request limit and time slot

const (
	REQUEST_LIMIT = 60
	TIME_SLOT     = 60 // in second
)

About ReqHolder structure

Thus we need to keep each request status by IP address. So we use ReqHolder structure from reqholder package, and define a map to keep its status.

var reqHolders map[string]*reqholder.ReqHolder

Count requests

reqHolders[ip].Count()

Validate and response

reqHolders[ip].Result()

Reset counter every n seconds

reqHolders[ip].Reset()