webpack-hot-middleware

What is webpack-hot-middleware?

The webpack-hot-middleware npm package enables hot reloading of webpack bundles during development. It works in conjunction with webpack-dev-middleware and listens to webpack's compilation to signal the client when updates are available. This allows developers to see changes in their application without a full page refresh, improving the development experience.

What are webpack-hot-middleware's main functionalities?

Hot Module Replacement (HMR) Setup

This code sample demonstrates how to set up a basic Express server with webpack-hot-middleware and webpack-dev-middleware for hot module replacement. It allows changes in the code to be automatically updated in the browser without a full refresh.

const webpack = require('webpack');
const express = require('express');
const webpackDevMiddleware = require('webpack-dev-middleware');
const webpackHotMiddleware = require('webpack-hot-middleware');
const config = require('./webpack.config.js');

const app = express();
const compiler = webpack(config);

app.use(webpackDevMiddleware(compiler, {
  publicPath: config.output.publicPath
}));
app.use(webpackHotMiddleware(compiler));

app.listen(3000, function () {
  console.log('Example app listening on port 3000!\n');
});

Other packages similar to webpack-hot-middleware

react-hot-loader

React Hot Loader is specifically designed for React applications. It allows React components to be live reloaded without the loss of state. It's more specialized compared to webpack-hot-middleware, which can be used with any webpack project.

browser-sync

BrowserSync is a tool that offers fast reloading capabilities across multiple devices. While it doesn't require webpack or integrate directly with it as webpack-hot-middleware does, it provides a broader set of features for live reloading and browser testing.

live-server

Live Server is a simple development http server with live reload capability. It's less integrated with webpack's ecosystem compared to webpack-hot-middleware, making it a more general-purpose solution for projects not using webpack.

README

Webpack Hot Middleware

Webpack hot reloading using only webpack-dev-middleware. This allows you to add hot reloading into an existing server without webpack-dev-server.

Installation & Usage

See example/ for an example of usage.

First, install the npm module.

npm install --save-dev webpack-hot-middleware

Next, enable hot reloading in your webpack config:

1. Add the following three plugins to the plugins array:

   plugins: [
       new webpack.optimize.OccurenceOrderPlugin(),
       new webpack.HotModuleReplacementPlugin(),
       new webpack.NoErrorsPlugin()
   ]
   

   Occurence ensures consistent build hashes, hot module replacement is somewhat self-explanatory, no errors is used to handle errors more cleanly.

2. Add 'webpack-hot-middleware/client' into the entry array. This connects to the server to receive notifications when the bundle rebuilds and then updates your client bundle accordingly.

Now add the middleware into your server:

1. Add webpack-dev-middleware the usual way

   var webpack = require('webpack');
   var webpackConfig = require('./webpack.config');
   var compiler = webpack(webpackConfig);
   
   app.use(require("webpack-dev-middleware")(compiler, {
       noInfo: true, publicPath: webpackConfig.output.publicPath
   }));
   

2. Add webpack-hot-middleware attached to the same compiler instance

   app.use(require("webpack-hot-middleware")(compiler));
   

And you're all set!

Changelog

2.0.0

Breaking Change

As of version 2.0.0, all client functionality has been rolled into this module. This means that you should remove any reference to webpack/hot/dev-server or webpack/hot/only-dev-server from your webpack config. Instead, use the reload config option to control this behaviour.

This was done to allow full control over the client receiving updates, which is now able to output full module names in the console when applying changes.

Documentation

More to come soon, you'll have to mostly rely on the example for now.

Config

Configuration options can be passed to the client by adding querystring parameters to the path in the webpack config.

'webpack-hot-middleware/client?path=/__what&timeout=2000&overlay=false'

• path - The path which the middleware is serving the event stream on
• timeout - The time to wait after a disconnection before attempting to reconnect
• overlay - Set to false to disable the DOM-based client-side overlay.
• reload - Set to true to auto-reload the page when webpack gets stuck.

License

Copyright 2015 Glen Mailer.

MIT Licened.