webpack.config.js

const { resolve } = require("path");
const webpack = require("webpack");

module.exports = {
  context: resolve(__dirname, "src"),

  entry: [
    "react-hot-loader/patch",
    // activate HMR for React

    "webpack-dev-server/client?http://localhost:8080",
    // bundle the client for webpack-dev-server
    // and connect to the provided endpoint

    "webpack/hot/only-dev-server",
    // bundle the client for hot reloading
    // only- means to only hot reload for successful updates

    "./index.js"
    // the entry point of our app
  ],
  output: {
    filename: "bundle.js",
    // the output bundle

    path: resolve(__dirname, "dist"),

    publicPath: "/"
    // necessary for HMR to know where to load the hot update chunks
  },

  devtool: "inline-source-map",

  devServer: {
    hot: true,
    // enable HMR on the server

    contentBase: resolve(__dirname, "dist"),
    // match the output path

    publicPath: "/"
    // match the output `publicPath`
  },

  module: {
    rules: [
      {
        test: /\.jsx?$/,
        use: [ "babel-loader", ],
        exclude: /node_modules/
      },
      {
        test: /\.css$/,
        use: [ "style-loader", "css-loader?modules", ],
      },
    ],
  },

  plugins: [
    new webpack.HotModuleReplacementPlugin(),
    // enable HMR globally

    new webpack.NamedModulesPlugin(),
    // prints more readable module names in the browser console on HMR updates
  ],
};