webpack.config.js

const path = require('path');

module.exports = {
  entry: './client/index.js',
  output: {
    path: path.resolve(__dirname, 'build'),
    filename: 'bundle.js'
  },
  devServer: {
    publicPath: '/build/',
    contentBase: '/build',
    hot: true,
    port: 8080,
    proxy: {
      '/': 'http://localhost:3000',
      '/api/': 'http://localhost:3000',
      '/auth/': 'http://localhost:3000',
      '/test/': 'http://localhost:3000'
    }
  },
  mode: process.env.NODE_ENV,
  module: {
    rules: [
      {
        test: /\.jsx?/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env', '@babel/preset-react']
          }
        }
      },
      {
        test: /\.css$/,
        use: [
          'style-loader', // creates style nodes from JS strings
          'css-loader' // translates CSS into CommonJS
        ]
      },
      {
        test: /\.(png|jpe?g|gif)$/,
        use: [
          {
            loader: 'file-loader',
            options: {}
          }
        ]
      }
    ]
  }
};