Gmail: delete old emails automatically

README.md

Gmail: delete old emails automatically

Automatically deletes old emails that match the specified label.

Get started

• Create a new Google Apps Script at https://script.google.com
• Overwrite the placeholder with the javascript below
• Update the following constants:
  • LABEL_TO_DELETE: the label that should be have old messages deleted
  • DELETE_AFTER_DAYS: the age of messsages after which they will be moved to trash
• Save the script, then run:
  • Initialize
  • Install

If you ever want to remove the script, run Uninstall to remove any left over triggers.

Getting the labels

To get the labels to configure your script, go into your Gmail and click in the sidebar for the label that you want to use in the filter. In the search bar a text like: label:some-label will appear, copy the content without the label: part.

Changelog

2019-05-01

• Added Session.getScriptTimeZone()
• Added simple stackdriver logging

2017-07-31

• Added support for multiple labels
• Added configurable TRIGGER_NAME
• Increased default page size
• Decreased default delay between receipt and delete

2016-01-21

• Removed use of deprecated Session.getTimeZone()
• Improved efficiency for long threads by checking thread.getLastMessageDate()

Acknowledgements

H/T: Arun's post How to Auto Delete Old Emails In Any Gmail Label

delete-by-label.gs

// The name of the Gmail Label that is to be checked for purging?
var LABELS_TO_DELETE = [
  "label",
  "label-subLabel"
];

// Purge messages in the above label automatically after how many days?
var DELETE_AFTER_DAYS = "15";

// Maximum number of threads to process per run
var PAGE_SIZE = 150;

// If number of threads exceeds page size, resume job after X mins (max execution time is 6 mins)
var RESUME_FREQUENCY = 10;

var TRIGGER_NAME = "dailyDeleteGmail";

/*

IMPLEMENTATION

*/
function Intialize() {
  return;
}

function Install() {
  // First run 2 mins after install
  ScriptApp.newTrigger(TRIGGER_NAME)
           .timeBased()
           .at(new Date((new Date()).getTime() + 1000*60*2))
           .create();
  
  // Run daily there after
  ScriptApp.newTrigger(TRIGGER_NAME)
           .timeBased().everyDays(1).create();
}

function Uninstall() {
  var triggers = ScriptApp.getProjectTriggers();
  for (var i=0; i<triggers.length; i++) {
    ScriptApp.deleteTrigger(triggers[i]);
  }
}

function dailyDeleteGmail() {
  var age = new Date();  
  age.setDate(age.getDate() - DELETE_AFTER_DAYS);    
  
  var purge  = Utilities.formatDate(age, Session.getScriptTimeZone(), "yyyy-MM-dd");
  var search = "(label:" + LABELS_TO_DELETE.join(" OR label:") + ") before:" + purge;
  Logger.log("PURGE: " + purge);
  Logger.log("SEARCH: " + search);
  
  try {
    var threads = GmailApp.search(search, 0, PAGE_SIZE);
    
    // Resume again in 10 minutes
    if (threads.length == PAGE_SIZE) {
      Logger.log("Scheduling follow up job...");
      console.info("Scheduling follow up job...");
      ScriptApp.newTrigger(TRIGGER_NAME)
               .timeBased()
               .at(new Date((new Date()).getTime() + 1000*60*RESUME_FREQUENCY))
               .create();
    }
    
    // Move threads/messages which meet age criteria to trash
    Logger.log("Processing " + threads.length + " threads...");
    console.info("Processing " + threads.length + " threads...");
    for (var i=0; i<threads.length; i++) {
      var thread = threads[i];
      
      if (thread.getLastMessageDate() < age) {
        thread.moveToTrash();
      } else {
        var messages = GmailApp.getMessagesForThread(threads[i]);
        for (var j=0; j<messages.length; j++) {
          var email = messages[j];       
          if (email.getDate() < age) {
            email.moveToTrash();
          }
        }
      }
    }
  } catch (e) {
    Logger.log(e);
    console.error(e);
  }
}