Create a Gmail filter to delete labelled messages from a conversation thread based on their age

Question

I have a Gmail filter that applies a label ('OTPs') to certain incoming messages. They accumulate and I want to keep most for only a couple of days.

I can eliminate them manually by performing a search (e.g. 'older_than:2d label:OTPs -label:GST') and then deleting the results, but I want to automate this process using a filter.

The example below shows a highlighted message thread 'SMS Forwarder' that totals 21 individual messages of which only 7 would match my criteria for deletion, and the remaining 14 would be kept.

Answer 1

I wrote a Google Apps script that archives threads with labels matching particular patterns: Gmail-archive-after-script. I've been using it for a couple of years now and couldn't bear my inbox without it.

I have not, however, done any testing on what I can do with individual messages in threads, and I'm too much of a coward to actually delete messages automatically.

Answer 2

Gmail only applies filters to incoming messages. If you want to automate the process, you can use a Google Apps Script.

I have created a script that can be used to delete individual messages based on a custom label that can be manually added or added via a Gmail filter. For example, a message labeled 'delete.in.3.days' would cause a message to be moved to TRASH if at least 3 days old.

I posted the code and installation instructions on Github at GAS-Gmail-Trash-by-Expiry-Label. The script has a Test Mode that allows it to be run without actually making any changes.

The code is long but includes a lot of logging which I prefer.