webpack.config.js

const HtmlWebpackPlugin = require('html-webpack-plugin');
const path = require('path');
const Dotenv = require('dotenv-webpack');

module.exports = {
  entry: './client/index.js',
  output: {
    path: path.resolve(__dirname, 'build'),
    filename: 'bundle.js'
  },
  mode: 'development',
  module: {
    rules:[
      {
        test: /\.jsx?/,
        exclude: /(node_modules|bower_components)/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env', '@babel/preset-react']
          }
        }
      },
      {
        test: /\.s[ac]ss$/i,
        use: [ 'style-loader', 'css-loader', 'sass-loader',]
      }
    ],
  },
  plugins: [
    new HtmlWebpackPlugin({ template: './index.html' }),
    new Dotenv({
      path: './.env', // load this now instead of the ones in '.env'
      safe: false, // load '.env.example' to verify the '.env' variables are all set. Can also be a string to a different file.
      allowEmptyValues: false, // allow empty variables (e.g. `FOO=`) (treat it as empty string, rather than missing)
      systemvars: false, // load all the predefined 'process.env' variables which will trump anything local per dotenv specs.
      silent: false, // hide any errors
      defaults: false, // load '.env.defaults' as the default values if empty.
      ignoreStub: false,
      prefix: 'process.env.' // reference your env variables as 'import.meta.env.ENV_VAR'.
    })
  ],
  devServer: {
    proxy: {
      '/server': 'http://localhost:3000'
    },
    static: {
      directory: path.resolve(__dirname, './build'),    
      publicPath: 'http://localhost8080/'
    },
    compress: true,
    port: 8080
  },
  resolve: {
    extensions: [".js", ".jsx", ".json", ".ts", ".tsx"],
  },
}