webpack-hot-middleware in webpack 4 not work, error is webpackHotUpdate is not defined

webpack 4.0.1 node:8.9.4 webpack-hot-middleware: 2.21.1

update to webpack 4,webpack-hot-middleware not working, when update code, hot-update.js has error that say webpackHotUpdate is not defined

import webpack from ‘webpack’;
import webpackHotMiddleware from ‘webpack-hot-middleware’;
import webpackDevMiddleware from ‘webpack-dev-middleware’;

import webpackConfig from ‘webpack/client/webpackDevConfig’;
export default function (app) {
const compiler = webpack(webpackConfig);
compiler.apply(new webpack.ProgressPlugin());
app.use(webpackDevMiddleware(compiler, {
lazy: false,
quiet: false,
noInfo: false,
publicPath: webpackConfig.output.publicPath,
stats: {
colors: true,
modules: false,
children: false,
chunks: false,
chunkModules: false,
app.use(webpackHotMiddleware(compiler, {
logLevel: ‘warn’,
log: console.log,
path: ‘/__webpack_hmr’,
heartbeat: 10 * 1000,

import webpack from ‘webpack’;
import cloneDeep from ‘lodash/cloneDeep’;
import webpackMerge from ‘webpack-merge’;
import webpackBaseConfig, { SUPPORT_BROWSERS } from ‘./webpackBaseConfig’;

const hotMiddlewareScript = ‘webpack-hot-middleware/client?path=/__webpack_hmr&timeout=20000&reload=true’;

const baseConfig = cloneDeep(webpackBaseConfig);
const entries = baseConfig.entry;
Object.keys(entries).forEach((key) => {
const val = entries[key];
if (!Array.isArray(val)) {
entries[key] = [hotMiddlewareScript].concat(entries[key]);
baseConfig.entry = entries;

export default webpackMerge.smart(baseConfig, {
mode: “development”,
plugins: [
new webpack.HotModuleReplacementPlugin(),
new webpack.NoEmitOnErrorsPlugin(),
new webpack.SourceMapDevToolPlugin({
filename: ‘[file].map’,
exclude: /(vendor).\w{6}.(js|css)/,
module: {
rules: [
test: /.(es6|js|jsx)$/,
exclude: /node_modules/,
loader: ‘babel-loader’,
options: {
babelrc: false,
cacheDirectory: ‘.tmp/babel-loader’,
presets: [
‘@babel/preset-env’, {
modules: false,
useBuiltIns: ‘usage’,
targets: { browsers: SUPPORT_BROWSERS },
plugins: [
[‘@babel/plugin-proposal-class-properties’, { loose: true }],
[‘import’, { libraryName: ‘antd-mobile’, style: true }],

Author: Fantashit

1 thought on “webpack-hot-middleware in webpack 4 not work, error is webpackHotUpdate is not defined

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