webpack.config.js

const path = require("path");
const HtmlWebpackPlugin = require("html-webpack-plugin");

module.exports = {
  entry: path.join(__dirname, "src/client.js"),
  output: {
    filename: "bundle.js",
    path: path.join(__dirname, "build")
  },
  mode: "development",
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /(node_modules)/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env", "@babel/preset-react"]
          }
        }
      },
      {
        test: /\.css$/,
        use: [{ loader: "style-loader" }, { loader: "css-loader" }]
      },
      {
        test: /\.html$/,
        use: [
          {
            loader: "html-loader"
          }
        ]
      }
    ]
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: path.join(__dirname, "src/index.html"),
      filename: "index.html"
    })
  ],
  devServer: {
    contentBase: path.join(__dirname, "build"),
    historyApiFallback: true,
    compress: true,
    port: 3000
  }
};