Webpack手动实现HMR的两种核心方案解析

"devDependencies": {
    "babel-core": "^6.26.3",
    "babel-loader": "^7.1.4",
    "babel-preset-env": "^1.7.0",
    "cross-env": "^5.1.6",
    "css-loader": "^0.28.11",
    "html-webpack-plugin": "^3.2.0",
    "moment": "^2.22.2",
    "vue-loader": "^15.2.4",
    "vue-template-compiler": "^2.5.16",
    "webpack": "^4.11.1",
    "webpack-cli": "^3.0.3",
    "webpack-merge": "^4.1.2"
  },
  "dependencies": {
    "babel-polyfill": "^6.26.0",
    "vue": "^2.5.16"
  }

const path = require('path');
const webpack = require('webpack');
const package = require('./../package.json');
const VueLoaderPlugin = require('vue-loader/lib/plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const moment = require('moment');
// 设置版本号
const buildVersion = moment().format('YYYY-MM-DD_HH_mm_ss');

module.exports = {
    entry: path.join(__dirname, '../src/pages/main.js'),
    output: {
        path: path.resolve(__dirname, '../dist'),
        publicPath: '/',
        filename: package.name + '.js'
    },
    module: {
        rules:[
            {
                test: /\.vue$/,
                loader: 'vue-loader',
                options: {}
            },
            {
                test: /\.css$/,
                use: [
                    'vue-style-loader',
                    'css-loader'
                ]
            },
            {
                test: /\.js$/,
                loader: 'babel-loader',
                exclude: /node_modules/
            }
        ]
    },
    plugins: [
        new VueLoaderPlugin(),
        new HtmlWebpackPlugin({
            version: buildVersion,
            filename: 'index.html',
            template: path.join(__dirname, '../src/pages/index.html'),
            inject: 'body'
        })
    ],
    externals: {
        'babel-polyfill': 'window'
    },
    devtool: 'source-map'
}

import 'babel-polyfill'
import Vue from 'vue'

import App from '../container/main.vue'

new Vue({
    el: '#app',
    render: h => h(App)
})

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>dev-server HRM</title>
    <meta name="robots" content="all" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=0, minimum-scale=1.0, maximum-scale=1.0, viewport-fit=cover"
    />
    <!-- 显示工具栏和菜单栏 -->
    <meta name="apple-mobile-web-app-capable" content="yes" />
    <!-- 工具栏和菜单栏样式 -->
    <meta name="apple-mobile-web-app-status-bar-style" content="black" />
    <!-- 针对手持设备优化，主要是针对一些老的不识别viewport的浏览器，比如黑莓 -->
    <meta name="HandheldFriendly" content="true" />
    <!-- 忽略页面中的数字识别为电话 -->
    <meta name="format-detection" content="telephone=no" />
</head>
<body>
    <div id="app"></div>
</body>
</html>

"scripts": {
  "dev": "cross-env NODE_ENV=development webpack-dev-server --config build/dev.config.js",
   "build": "cross-env NODE_ENV=production webpack-dev-server --config build/build.config.js",
  "test": "echo \"Error: no test specified\" && exit 1"
}

const webpack = require('webpack')
const config = require('./webpack.config.js')

// webpack4开始需要配置的变量
config.mode = "development";

config.devServer = {
    historyApiFallback:true,
    // hot参数控制更新是刷新整个页面还是局部刷新
    hot: true,
    // inline是热更新的一种模式，另一种是iframe
    inline: true,
    port: 80
}

// 也一定要加上HotModuleReplacementPlugin
config.plugins.push(
    new webpack.HotModuleReplacementPlugin()
)

// 需要导出
module.exports = config;

"scripts": {
  "dev": "cross-env NODE_ENV=development node ./build/dev.config.js",
  "build": "cross-env NODE_ENV=production node ./build/build.config.js",
  "test": "echo \"Error: no test specified\" && exit 1"
},

const app = require('express')();
const webpack = require("webpack");
const webpackDevMiddleware = require("webpack-dev-middleware");
const webpackHotMiddleware = require("webpack-hot-middleware");
const path = require("path");
let config = require("./webpack.config")

config.mode = "development";

// 灰常重要
config.entry = [config.entry,'webpack-hot-middleware/client'];

config.plugins.push(
    new webpack.HotModuleReplacementPlugin(),
    // 当开启 HMR 的时候使用该插件会显示模块的相对路径，建议用于开发环境
    new webpack.NamedModulesPlugin()
)

const compiler = webpack(config);

// 使用dev-middleware与hot-middleware

const devMiddleware = webpackDevMiddleware(compiler, {
    publicPath: config.output.publicPath,
    quiet: true
})

const hotMiddleware = webpackHotMiddleware(compiler, {
    log: false,
    heartbeat: 2000
})

app.use(devMiddleware);
app.use(hotMiddleware);
app.listen(80);