downloadFile.js

function downloadFile(finalData) {
  const data = new Blob([JSON.stringify(finalData, null, 2)], {type : 'application/json'});

  if (navigator.msSaveBlob) {
    // IE 10+.
    navigator.msSaveBlob(data, 'directory.json');
  } else {
    const link = document.createElement('a');
    if (link.download !== undefined) {
      // Feature detection for Browsers that support HTML5 download attribute.
      const url = URL.createObjectURL(data);
      link.setAttribute('href', url);
      link.setAttribute('download', 'directory.json');
      link.style.visibility = 'hidden';
      document.body.appendChild(link);
      link.click();
      document.body.removeChild(link);
    }
  }
}