webpack - css分离 热更新HMR （三）

版权声明：尊重原创！ https://blog.csdn.net/weixin_42675488/article/details/87387587

参考文献：webpack那些事儿 - 掘金

exract-text-webpack-plugin css分离 实操：

1、安装：

npm 安装实操
webpack 3.x 版本 ——	npm i exract-text-webpack-plugin -D
webpack 4.x 版本 ——	npm i exract-text-webpack-plugin@next -D
	——
css处理：	npm i style-loader css-loader -D
/
图片img处理：	npm i file-loader url-loader -D
	npm i html-withimg-loader -D

2、webpack.config.js 配置：

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const Webpack = require('webpack');
const ExtractTextPlugin = require('extract-text-webpack-plugin');  //分离css插件名

module.exports = {
    entry: {
        index: './src/js/index.js'
    },
    output: {
        path: path.resolve(__dirname , './dist'), //文件地址
        filename: 'js/[name].bundle.js'
    },
    module: {
        rules:[
            {
                test: /\.css$/,
                loader: ExtractTextPlugin.extract({
                    //安装两个包
                    fallback: "style-loader",
                    use: "css-loader"
                })
            },
            {
                test: /\.(png|jpg|gif)$/,
                use: [{
                    loader: 'url-loader',
                    options: {
                        limit: 50 , //limit - 范围，小于50kb转成base64，大于则换成路径
                        name: 'assets/images/[name].[hash:7].[ext]'  //hash- 随机转化，防止重名
                    }
                }]
            },
            {
                test: /\.html$/,
                loader: 'html-withimg-loader'
            }
        ]
    },
    plugins: [
        new HtmlWebpackPlugin ({
            hash: true,
            filename: 'index.html',
            template: './src/index.html'
        }),
        new ExtractTextPlugin('css/index.css') //提取路径
    ]
};

---

devSerer 开发服务器实操：

1、安装：

npm安装实操：
	npm i webpack-dev-server -D
	npm i internal-ip -D
	npm webpack -D
删除文件夹：	npm i clean-webpack-plugin -D
	——
	webpack 使用方法 — segmentfault
	配置图片、手机访问等 webpack 方法

—— Webpack DevServer配置：

devServer:{-------------------- //设置webpack本地服务器的配置
contentBase:’./dist’,--------------------------------- //默认webpack-dev-server会为根文件夹提供本地服务器
port:‘8383’,--------------------------------------//监听端口
inline:true,----------------------------//设置为true，当源文件改变的时候会自动刷新
historyApiFallback:true,-----------//在开发单页应用时非常有用，它依赖于HTML5 history API，如果设置为true，所有的跳转将指向index.html
hot:true --------------------------------------//允许热加载
hotOnly: true, ------------------------ //当编译失败时，不刷新页面
overlay: true,-------------------------- //用来在编译出错的时候，在浏览器页面上显示错误
progress:true------------------------------ //显示打包的进度
},

2、配置：

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const Webpack = require('webpack');
const ExtractTextPlugin = require('extract-text-webpack-plugin');  //分离css插件名
const CleanWebpackPlugin = require('clean-webpack-plugin');  //build 编译后删除并重新编译dist文件

const publicPath = '/';

module.exports = {
    entry: {
        index: './src/js/index.js'
    },
    output: {
        path: path.resolve(__dirname , './dist'), //文件地址
        filename: 'js/[name].bundle.js'
        /* 
        //解析文件的目录,在devServer处理css中的图片时会用到，webpack-dev-server伺服的文件是相对publicPath这个路径
        publicPath: '/assets/'
        //此时相当于/assets/路径对应于 dist 目录，是一个映射的关系
        */
    },
    devtool: 'inline-source-map',
    devServer: {
        publicPath: publicPath, //output.path 的虚拟路径映射
        contentBase: path.resolve(__dirname,'dist'),
        compress: true, //开启资源的 gzip 压缩
        host: 'localhost',
        historyApiFallback:true,  //单页应用 404 转向 index.html
        inline:true,
        progress:true, 
        hot:true,
        hotOnly: true, 
        overlay: true,
        port:8080
    },
    module: {
        rules:[
            {
                test: /\.css$/,
                use: ExtractTextPlugin.extract({
                    //安装两个包
                    fallback: "style-loader",
                    use: "css-loader",
                    publicPath: '../'   //解决css背景图的路径问题
                })
            },
            {
                test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,
                loader: 'url-loader',
                options: {
                    limit: 50 , //limit - 范围，小于50kb转成base64，大于则换成路径
                    name: 'assets/images/[name].[hash:7].[ext]'  //hash- 随机转化，防止重名
                }
            },
            {
                test: /\.html$/,
                loader: 'html-withimg-loader'
            }
        ]
    },
    plugins: [
        new CleanWebpackPlugin(['dist']),
        new Webpack.HotModuleReplacementPlugin(),  //HMR
        new Webpack.NamedModulesPlugin(),
        new HtmlWebpackPlugin ({
            hash: true,
            filename: 'index.html',
            template: './src/index.html'
        }),
        new ExtractTextPlugin('css/index.css') //提取路径
    ]
};

问题： webpack-dev-server 热更新 HMR配置有问题，浏览器提示404

HMR配置有两种方式：Node方式和非Node方式。非Node方式

配置成功！

所以我现在的package.json：

{
  "name": "webpack02",
  "version": "1.0.0",
  "description": "",
  "main": "webpack.config.js",
  "scripts": {
    "build": "webpack --mode development",
    "dev": "webpack-dev-server --hot --open chrome --mode development"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "clean-webpack-plugin": "^1.0.1",
    "css-loader": "^2.1.0",
    "extract-text-webpack-plugin": "^4.0.0-beta.0",
    "file-loader": "^3.0.1",
    "html-webpack-plugin": "^3.2.0",
    "html-withimg-loader": "^0.1.16",
    "internal-ip": "^3.0.1",
    "style-loader": "^0.23.1",
    "stylus": "^0.54.5",
    "url-loader": "^1.1.2",
    "webpack": "^4.29.3",
    "webpack-cli": "^3.2.3",
    "webpack-dev-server": "^3.1.14"
  }
}