gmailAutomaticUpdates.gs

/*
Google Apps Script to automatically archive or delete mail with a certain label after a certain time

Copyright @tedsteinmann https://gist.github.com/tedsteinmann/0ee248856de6e75498470db7c98fab09

Original author fwed (contact@fwed.fr)
https://medium.com/@fw3d/auto-archive-emails-in-gmail-after-2-days-1ebf0e076b1c

Use at your own risk. The author is not responsible for erroneous deletion of email.

See full project and installation at: https://github.com/tedsteinmann/gmailAutoUpdate/
*/

function automaticGmailUpdates() {
  _automaticGmailUpdates('auto/delete/daily', 1);
  _automaticGmailUpdates('auto/delete/weekly', 7);
  _automaticGmailUpdates('auto/delete/monthly', 30);

  _automaticGmailUpdates('auto/archive/daily', 1);
  _automaticGmailUpdates('auto/archive/weekly', 7);
  _automaticGmailUpdates('auto/archive/monthly', 30);
}

function _automaticGmailUpdates(labelName, minimumAgeInDays) {

  // if an instance of "auto/delete" is found in the label name, set flag to delete it.
  if (labelName.indexOf("auto/delete")>=0) {
    var update = 'delete';
  }
  //otherwise, if instance of "auto/archive" is found, set flag to archive it
  else if (labelName.indexOf("auto/archive")>=0) {
    var update = 'archive'
  }

  Logger.log('Running automatic updates for label %s (minimum age in days: %s)', labelName, minimumAgeInDays);

  // Threshold for latest message of the thread.
  var thresholdDate = new Date();
  thresholdDate.setDate(thresholdDate.getDate() - minimumAgeInDays);
  Logger.log('Using threshold date %s', thresholdDate);

  // Get all the threads with the label.
  var label = GmailApp.getUserLabelByName(labelName);

  if (label) {
    Logger.log('Found label: %s', label.getName());

  var threads = label.getThreads(0, 400).filter(function(thread) {
    // Only include threads older than the limit we set in delayDays
    return (thread.getLastMessageDate() < thresholdDate);
  });

    if (threads.length == 0){
      Logger.log('Found 0 threads to update');
      return -1;
    }

  var batch_size = 100;
  while (threads.length) {
    //set the batch size to the minimum of 100 or size of threads
    var this_batch_size = Math.min(threads.length, batch_size);
    var this_batch = threads.splice(0, this_batch_size);

    if (update === 'delete') {
      Logger.log('Found %s threads to delete', this_batch.length);
      GmailApp.moveThreadsToTrash(this_batch)
    }
    else if (update === 'archive') {
      Logger.log('Found %s threads to archive', this_batch.length);
      GmailApp.moveThreadsToArchive(this_batch);
      //when archiving, we need to remove this label so that it doesn't get run again.
      label.removeFromThreads(this_batch);
    }
  }//end while
  }//end if label
}// end function