关于koa:koa项目热更新和es6语法兼容

热更新很简略，须要应用到nodemon。

用法如下：

npm i nodemon -D

// package.json"scripts": {    "start": "nodemon src/index.js"  },

而后运行npm run start

es语法反对
这里须要用到如下插件：

webpack & webpack-cli
clean-webpack-plugin: 革除dist目录
webpack-node-externals: 不对node_modules进行解决
@babel/core: es6反对
@babel/node: 调试应用
@babel/preset-env: 新语法的反对
babel-loader
cross-env: 环境变量的解决

webpack.config.js 配置如下：

const path = require('path');var nodeExternals = require('webpack-node-externals');const { CleanWebpackPlugin } = require('clean-webpack-plugin');const webpackconfig = {  target: 'node',  mode: 'development',  entry: {    server: path.join(__dirname, 'src/index.js')  },  devtool: 'eval-source-map',  output: {    filename: '[name].bundle.js',    path: path.join(__dirname, './dist')  },  module: {    rules: [      {        test: /\/(js|jsx)$/,        use: {          loader: 'babel-loader'        },        exclude: [path.join(__dirname, '/node_modules')]      }    ],    },    externals: [nodeExternals()],    plugins: [      new CleanWebpackPlugin()    ],    node: {      console: true,      global: true,      process: true,      Buffer: true,      __filename: true,      __dirname: true,      setImmediate: true,      path: true    }  }module.exports = webpackconfig

.babelrc 配置如下:

{  "presets": [    [      "@babel/preset-env",      {        "targets": {          "node": "current"        }      }    ]  ]}

而后执行如下命令:

npx babel-node src/index.js

就能够应用import 语法了。

当然，我还想联合应用热更新怎么办呢？

"scripts": {    "start": "nodemon src/index.js",    "start:es6": "nodemon --exec babel-node src/index.js"  },