webpack.config.umd.js

/* globals __dirname */
const webpack = require('webpack');
const path = require('path');
const UglifyJsPlugin = require('uglifyjs-webpack-plugin');

module.exports = {
  mode: 'production',
  entry: path.join(__dirname, 'src/index.js'),
  externals: [
    {
      'react': {
        root: 'React',
        commonjs2: 'react',
        commonjs: 'react',
        amd: 'react'
      },
      'react-dom': {
        root: 'ReactDom',
        commonjs2: 'react-dom',
        commonjs: 'react-dom',
        amd: 'react-dom'
      }
    }
  ],
  output: {
    library: 'ReactProgressiveImage',
    libraryTarget: 'umd',
    filename: 'react-progressive-image.min.js',
    path: path.join(__dirname, 'umd')
  },
  module: {
    rules: [{
      test: /\.js$/,
      exclude: /node_modules/,
      loader: 'babel-loader'
    }]
  },
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
        warnings: false
      }})
    ]   
  },
  plugins: [
    new webpack.DefinePlugin({
      'process.env.NODE_ENV': JSON.stringify('production')
    }),
    new webpack.SourceMapDevToolPlugin({
      filename: '[file].map'
    })
  ]
};