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cnpm i --save-dev koa2 koa-router koa-body koa-static request

npm install --save koa2

const koa2 = require('koa2');

const Router = require('koa-router');

const router = new Router();

const app = new koa2();

const Index = router.get('/', async (ctx, next) =>{

  await next();

  ctx.status = 200;

  ctx.type= 'html';

  ctx.body = "<h1>hello</h1>"

}).routes();

app.use(Index);

app.listen(1995);

npm i koa-router --save 路由控件

const Index = require('./router/index.js');

app.use(Index);// 挂载路由

// router/index.js

const Router = require('koa-router');

const router = new Router();

router.get('/', async (ctx, next) =>{

  await next();

  ctx.status = 200;

  ctx.type= 'json'

  ctx.body = {msg:''};

}).routes();

module.exports = router

npm i koa-views --save 加载静态页面

var views = require('koa-views');

// 在所有路由之前使用

app.use( views(path.join( __dirname, 'view' )) );

npm i --save koa-static 加载静态资源

const static = require('koa-static');

app.use(static('./public'));// 加载静态文件

获取ip

  console.log( Object.getOwnPropertyNames(ctx.request) );

   console.log(ctx.request.ip)