bundler.js

const Bundler = require('parcel-bundler');
const Path = require('path');

// Single entrypoint file location:
const entryFiles = Path.join(__dirname, './src/index.html');
// OR: Multiple files with globbing (can also be .js)
// const entryFiles = './src/*.js';
// OR: Multiple files in an array
// const entryFiles = ['./src/index.html', './some/other/directory/scripts.js'];

process.env.NODE_ENV = 'production';

// Bundler options
const options = {
  outDir: './dist', // The out directory to put the build files in, defaults to dist
  outFile: 'index.html', // The name of the outputFile
  publicUrl: './', // The url to serve on, defaults to '/'
  watch: false, // Whether to watch the files and rebuild them on change, defaults to process.env.NODE_ENV !== 'production'
  cache: false, // Enabled or disables caching, defaults to true
  // cacheDir: '.cache', // The directory cache gets put in, defaults to .cache
  contentHash: true, // Disable content hash from being included on the filename
  global: 'moduleName', // Expose modules as UMD under this name, disabled by default
  minify: true, // Minify files, enabled if process.env.NODE_ENV === 'production'
  scopeHoist: true, // Turn on experimental scope hoisting/tree shaking flag, for smaller production bundles
  target: 'browser', // Browser/node/electron, defaults to browser
  bundleNodeModules: true, // By default, package.json dependencies are not included when using 'node' or 'electron' with 'target' option above. Set to true to adds them to the bundle, false by default
  logLevel: 3, // 5 = save everything to a file, 4 = like 3, but with timestamps and additionally log http requests to dev server, 3 = log info, warnings & errors, 2 = log warnings & errors, 1 = log errors
  sourceMaps: false, // Enable or disable sourcemaps, defaults to enabled (minified builds currently always create sourcemaps)hmrHostname: '', // A hostname for hot module reload, default to ''
  detailedReport: true // Prints a detailed report of the bundles, assets, filesizes and times, defaults to false, reports are only printed if watch is disabled
};

(async function() {
  // Initializes a bundler using the entrypoint location and options provided
  const bundler = new Bundler(entryFiles, options);

  // Run the bundler, this returns the main bundle
  // Use the events if you're using watch mode as this promise will only trigger once and not for every rebuild
  const bundle = await bundler.bundle();
})();