webpack之devserver介绍

dev-server

安装开发服务器的库

1	npm i -D webpack-dev-server

在packag.json添加运行命令start

{
  "name": "2",
  "version": "1.0.0",
  "description": "",
  "main": "webpack.config.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "dev": "webpack --config webpack.config.dev.js",
    "start": "webpack-dev-server --config webpack.config.dev.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "babel-core": "^6.26.0",
    "babel-loader": "^7.1.2",
    "babel-preset-react": "^6.24.1",
    "html-webpack-plugin": "^2.30.1",
    "webpack": "^3.5.5",
    "webpack-dev-server": "^2.8.2"
  },
  "dependencies": {
    "react": "^15.6.1",
    "react-dom": "^15.6.1"
  }
}

运行,开启服务器，开启服务器的时候，首先找到配置文件，先帮我们打包，打包完成之后，再让我们去访问已经打包好的资源。所以后面要加–config webpack.config.dev.js找到配置文件

1	npm run start

注意：这里dev-server打包后的资源并不是放到硬盘里面，而是打包后放到内存里面，所以文件夹下面并没有生成新的打包资源文件。

定制化配置

webpack.config.dev.js

const HtmlWebpackPlugin = require('html-webpack-plugin');
const path = require('path');

module.exports = {
    entry: './src/app.js',
    output: {
        path: path.resolve(__dirname, 'dist'),
        filename: 'app.js',
    },
    plugins: [
        new HtmlWebpackPlugin({
            filename: 'index.html',
            template: 'src/index.html'
        })
    ],
    module: {
        rules: [{
            test: /\.js$/,
            use: [{
                loader: 'babel-loader',
                options: {
                    presets: ['react']
                }
            }]
        }]
    },
    devServer: {
        open: true,
        port: 9000
    }
};