1、首先需要node（去官网下载）

2、见一个文件夹  比如koa          cmd——r       cd  koa文件

3、npm init

4、安装webpack       （本地安装）

npm install --save-dev webpack

4.1、用webpack4+  还需要安装webpack-cli

npm install --save-dev webpack-cli

5、安装koa    （记住，package.json内的项目名称不能叫koa   否则安装不了koa）

npm install koa --save

6、安装其他依赖

npm install koa-compress --save
npm install koa-router --save
npm install koa-compress --save
npm install koa-static --save

package.json文件

{
  "name": "testKoa",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "serve":"node app.js"
  },
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "webpack": "^4.31.0",
    "webpack-cli": "^3.3.2"
  },
  "dependencies": {
    "koa": "^2.7.0",
    "koa-compress": "^3.0.0",
    "koa-router": "^7.4.0",
    "koa-static": "^5.0.0"
  }
}

app.js

const koaStatic = require("koa-static");
const compress = require("koa-compress");
const path = require("path");
const fs = require("fs");
const app = new Koa();

app.use(compress());
app.use(koaStatic(path.resolve(__dirname,"./")));
const router = koaRouter();

router.get("*",async(ctx,next)=>{
    ctx.type="html",
    ctx.body=fs.readFileSync(path.resolve('./dist/index.html'),'utf-8')
    
});

app.use(router.routes()).use(router.allowedMethods());

app.listen(3000,()=>{
    console.log("server run on  localhost:3000");
})

 将dist的文件放到跟目录

运行npm run serve