Koa Proxies

Koa@2.x/next middlware for http proxy

Powered by http-proxy.

Installation

1$ npm install koa-proxies --save

Options

http-proxy events

1options.events = {
2  error (err, req, res) { },
3  proxyReq (proxyReq, req, res) { },
4  proxyRes (proxyRes, req, res) { }
5}

log option

1// enable log
2options.logs = true; // or false
3
4// custom log function
5options.logs = (ctx, target) {
6  console.log('%s - %s %s proxy to -> %s', new Date().toISOString(), ctx.req.method, ctx.req.oldPath, new URL(ctx.req.url, target))
7}

Usage

1// dependencies
2const Koa = require('koa')
3const proxy = require('koa-proxies')
4const httpsProxyAgent = require('https-proxy-agent')
5
6const app = new Koa()
7
8// middleware
9app.use(proxy('/octocat', {
10  target: 'https://api.github.com/users/',
11  changeOrigin: true,
12  agent: new httpsProxyAgent('http://1.2.3.4:88'), // if you need or just delete this line
13  rewrite: path => path.replace(/^\/octocat(\/|\/\w+)?$/, '/vagusx'),
14  logs: true
15}))

The 2nd parameter options can be a function. It will be called with the path matching result (see path-match for details) and Koa ctx object. You can leverage this feature to dynamically set proxy. Here is an example:

1// dependencies
2const Koa = require('koa')
3const proxy = require('koa-proxies')
4
5const app = new Koa()
6
7// middleware
8app.use(proxy('/octocat/:name', (params, ctx) => {
9  return {
10    target: 'https://api.github.com/',
11    changeOrigin: true,
12    rewrite: () => `/users/${params.name}`,
13    logs: true
14  }})
15)

Moreover, if the options function return false, then the proxy will be bypassed. This allows the middleware to bail out even if path matching succeeds, which could be helpful if you need complex logic to determine whether to proxy or not.

Attention

Please make sure that koa-proxies is in front of koa-bodyparser to avoid this issue 55

1const Koa = require('koa')
2const app = new Koa()
3const proxy = require('koa-proxies')
4const bodyParser = require('koa-bodyparser')
5
6app.use(proxy('/user', {
7  target: 'http://example.com',
8  changeOrigin: true
9}))
10
11app.use(bodyParser())