A Google Apps Script script to bulk delete large amounts of email in Gmail while avoiding the error #793 which Gmail encounters normally

batch-delete-gmail-emails.js

/*
This script, when used with Google Apps Scripts will delete 400 emails and
can be triggered to run every few minutes without user interaction enabling you
to bulk delete email in Gmail without getting the #793 error from Gmail.

Google returns a maximum of 500 threads. This limits to 400 threads in case 500
threads is causing timeouts

Configure the search query in the code below to match the type of emails
you want to delete
Browser to https://script.google.com/.
Start a script and paste in the code below. 
After you past it in, save it and click the little clock looking button.
This is for your triggers. You can set up how frequently you want the script
to run (I did mine for every minute but others are seeing execution take longer than
a minute in which case you may want to run every 5 or 15 minutes).

This writeup from @timur-tabi goes into more detail : https://docs.google.com/document/d/1PLfAnNus-B87gHS1pkbmzFTkWckAPNcqmvO7hFo_gBc/edit

Source : # https://productforums.google.com/d/msg/gmail/YeQVDuPIQzA/kpZPDDj8TXkJ
*/

function batchDeleteEmail() {
  var batchSize = 100 // Process up to 100 threads at once
  var searchSize = 400 // Limit search result to a max of 400 threads. Use this if you encounter the "Exceeded maximum execution time" error
  
  var threads = GmailApp.search('label:inbox from:user@example.com', 0, searchSize);
  for (j = 0; j < threads.length; j+=batchSize) {
    GmailApp.moveThreadsToTrash(threads.slice(j, j+batchSize));
  }
}

@timur-tabi Thank you, I've added your suggestion to the gist above and linked to your Google Doc.

So the script has been working fine for most times (trigger is setup for one per hr) with searchSize = 400. However I still get the Exceeded maximum execution time once in a while and sometimes says Exception: Gmail operation not allowed. Out of 24 a day (one/hr) I get 3 failed with gmail operation not allowed and 3 timedout with execeeded max execution time. 75% success rate (yikes). Google GMAIL api is pretty unstable seems like.

Thank you. This script is very helpful to me. I release a new version to everyone. By the way, I added Mandarin in the comments. Hope it helps others.

function batchDeleteEmail() {
  var batchSize = 100 // Process up to 100 threads at once
  // 如果需要時間可以加上 [older_than:00m、00d、00h]，[category:] 可換成 [label:]
  // If you need to add time conditions, you can use d(day) and h(hours) instead.
  // [category:] can be replace [label:].
  var threads = GmailApp.search('category:forums');
  console.log('batch size is: ' + threads.length);
  for (j = 0; j < threads.length; j+=batchSize) {
    console.log('removing batch: ' + j);
    GmailApp.moveThreadsToTrash(threads.slice(j, j+batchSize));
  }
}

Thank you so much! For anyone else wanting to delete patches, this is my

function batchDeleteEmail() {
  var batchSize = 100 // Process up to 100 threads at once
  var searchSize = 400 // Limit search result to a max of 400 threads. Use this if you encounter the "Exceeded maximum execution time" error
  
  var threads = GmailApp.search('subject: PATCH', 0, searchSize);
  for (j = 0; j < threads.length; j+=batchSize) {
    GmailApp.moveThreadsToTrash(threads.slice(j, j+batchSize));
  }
}

How to add multiple email addresses to the list?

I have an issue and I can't debug it. Is it me or the docs are a little bit stingy? Anyways, I cannot run the script as it says
Exception: Gmail Operation not allowed
On the line using GmailApp.search. Oddly enough, I left it running for something like an hour and it was working but then it stopped working. It sounds like a limit hit? but I am unsure as I am getting a Gmail operation not allowed and not something like limit error or something else. Any possible ideas?

Thank you!

How to add multiple email addresses to the list?

@birajblg1987 You can customize the GMail search terms on line 27 in any way you wish, including adding additional email addresses.

@Hectorhammett Indeed, @asifiqbal also mentions above encountering that limit.