webpack.config.js

const path = require("path");
const Dotenv = require('dotenv-webpack');
const HtmlWebpackPlugin = require("html-webpack-plugin");
const MomentLocalesPlugin = require('moment-locales-webpack-plugin');

module.exports = {
  devServer: {
    static: {
      directory: path.join(__dirname, "/build"),
      publicPath: "/",
    },
    hot: true,
    historyApiFallback: true,
    compress: true,
    port: 8080,
    proxy: {
      "/api": "http://localhost:3000",
    },
  },
  //This property defines where the application starts
  entry: path.resolve(__dirname, "src", "index.js"),

  //This property defines the file path and the file name which will be used for deploying the bundled file
  output: {
    path: path.join(__dirname, "/build"),
    filename: "bundle.js",
    publicPath: "/",
  },
  mode: process.env.NODE_ENV,
  resolve: {
    extensions: ['.js', '.jsx']
  },
  //Setup loaders
  module: {
    rules: [
      {
        test: /\.m?js$/,
        enforce: 'pre',
        use: ['source-map-loader'],
      },
      {
        test: /\.(jsx|js)$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env", "@babel/preset-react"],
          },
        },
      },
      {
        test: /\.css$/i,
        use: [
          'style-loader', 'css-loader', 'postcss-loader'
        ],
      },
      {
        test: /\.(gif|png|jpe?g|svg)$/i,
        use: [
          'file-loader',
          {
            loader: 'image-webpack-loader',
            options: {
              bypassOnDebug: true, // webpack@1.x
              disable: true, // webpack@2.x and newer
            },
          },
        ],
      }
    ],
  },

  // Setup plugin to use a HTML file for serving bundled js files
  plugins: [
    new Dotenv(),
    new HtmlWebpackPlugin({
      favicon: path.resolve(__dirname, "src/images/favicon.png"),
      template: path.resolve(__dirname, "index.html"),
    }),
    new MomentLocalesPlugin(),

        // Or: To strip all locales except “en”, “es-us” and “ru”
        // (“en” is built into Moment and can’t be removed)
        new MomentLocalesPlugin({
            localesToKeep: ['es-us', 'ru'],
        })
  ],
};