webpack.config.js

const UglifyJsPlugin = require('uglifyjs-webpack-plugin');

module.exports = {
  mode: 'production',
  entry: {
    'viamapi-client': ['core-js/fn/promise', './src/viamapi-client.js'],
    'viamapi-iframe': ['babel-polyfill', './src/viamapi-iframe.js'],
    'wopiapi-iframe': './src/wopiapi-iframe.js'
  },
  module: {
    rules: [
      {
        test: /\.m?js$/,
        //exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env']
          }
        }
      }
    ]
  },
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
          mangle: false
        }
      })
    ]
  }
};