Node 代理访问的实现

const Koa = require('koa2');
const app = new Koa();
// logger
app.use(async (ctx, next) => {
 console.log('第一层洋葱 - 开始')
 await next();
 const rt = ctx.response.get('X-Response-Time');
 console.log(`${ctx.method} ${ctx.url} - ${rt}`);
 console.log('第一层洋葱 - 结束')
});
// x-response-time
app.use(async (ctx, next) => {
 console.log('第二层洋葱 - 开始')
 const start = Date.now();
 await next();
 const ms = Date.now() - start;
 ctx.set('X-Response-Time', `${ms}ms`);
 console.log('第二层洋葱 - 结束')
});
// response
app.use(async ctx => {
 console.log('第三层洋葱 - 开始')
 ctx.body = 'Hello World';
 console.log('第三层洋葱 - 结束')
});
app.listen(8000);
// 输出
第一层洋葱 - 开始
第二层洋葱 - 开始
第三层洋葱 - 开始
第三层洋葱 - 结束
第二层洋葱 - 结束
第一层洋葱 - 结束

setQuestUrl 此方法主要是将前端访问的路径，根据第一级转发到不同的host上

例如： /t -> host1

3.3 转发请求 httpRequest.js

本例主要为了代理访问并携带Cookie, const.js 为写死的要携带的cookie

let koa2Req = require('koa2-request')
let constConfig = require('./const')
let iToken = constConfig.iToken
let koaRequest = async function(url, method, ctx) {
 let options = {
  method: method,
  uri: url,
  timeout: 120000,
  body: ctx
   ? {
     ...ctx.request.body
    }
   : null,
  headers: {},
  json: true // Automatically stringifies the body to JSON
 }
 options.headers['Cookie'] = `i-token=${iToken}` //设置cookie
 let res = await koa2Req(options)
 return res.body
}
// node-mon
async function getTestToken() {
 if (!constConfig.iToken) {
  let url = `http://xt.eqxiu.com/tui/app/radar/test/getToken?companyId=${constConfig.companyId}&staffId=${constConfig.staffId}`
  try {
   let res = await koaRequest(url, 'GET')
   iToken = res.obj
   console.log('token已拿到：' + iToken)
  } catch (e) {
   console.log(e)
  }
 }
}
getTestToken()
module.exports = koaRequest

3.4 最后设置端口等

const app = require('./app')
//const createWebsocket = require('./websocket')
const server = require('http').createServer(app.callback())
server.setTimeout(2 * 60 * 1000) //设置超时时间
const { PORT = 3000 } = process.env
server.listen(PORT, () => {
 console.log(`Listening on port ${PORT}`)
})

3.5 本地开发，热重启

安装 nodemon

yarn add nodemon