Change Folder Permissions in Google Drive with Apps Script

This Google Apps Script will change the access permissions of the specified Google Drive folder from Public to Private at a custom date and time. When you initialize the script, it creates a time-based trigger that is responsible for change the shared permissions.

Google Scripts has a simple file.removeViewer(user) method to remove one or more users from a shared File but it doesn’t seem to work when the file /folder is shared with Public. Thus the workaround, as used in this script, is to create a copy of the shared folder and delete the original one thus expiring the shared links.

// Enter the full URL of the public Google Docs folder
var FOLDER_URL = 'https://docs.google.com/folder/d/1234567890/edit';

// Enter the expiry date in YYYY-MM-DD HH:MM format (local time zone)
var EXPIRY_TIME = '2013-02-15 18:30';

function getFolderID() {
  var search = /docs\.google\.com\/folder\/d\/(.*)\//g;
  var results = search.exec(FOLDER_URL);

  var id = '0';

  if (search.lastIndex) id = results[1];

  return id;
}

function Start() {
  var ID = getFolderID();

  if (ID == '0') {
    MailApp.sendEmail(
      Session.getActiveUser(),
      'Error',
      'Check the URL of the shared Google Docs folder : ' + FOLDER_URL
    );
    return;
  }

  var time = EXPIRY_TIME;

  var expireAt = new Date(
    time.substr(0, 4),
    time.substr(5, 2) - 1,
    time.substr(8, 2),
    time.substr(11, 2),
    time.substr(14, 2)
  );

  if (!isNaN(expireAt.getTime())) ScriptApp.newTrigger('autoExpire').timeBased().at(expireAt).create();
  else
    MailApp.sendEmail(
      Session.getActiveUser(),
      'Error',
      "The auto-expiry date isn't in proper format. Please use YYYY-MM-DD HH:MM"
    );
}

function autoExpire() {
  try {
    var folder = DocsList.getFolderById(Initialize());

    if (folder) {
      var name = folder.getName();
      var copy = DocsList.createFolder(name + ' (Private)');

      var files = folder.getFiles();

      for (var i = 0; i < files.length; i++) {
        files[i].removeFromFolder(folder);
        files[i].addToFolder(copy);
      }

      folder.setTrashed(true);
      copy.rename(name);

      MailApp.sendEmail(
        Session.getActiveUser(),
        'Success',
        'Your shared files are no longer public and the new (private) URL is :' + copy.getUrl()
      );
    }
  } catch (e) {
    MailApp.sendEmail(Session.getActiveUser(), 'Error', 'Could not set the expiry date for your file. ' + e.toString());
  }
}

Awards & Recognition