autodelete notification messages to improve performance of meetup-notifications

[kentcdodds]

I'm guessing the amount of mentions in the meetup-notifications is causing a performance issue. We should delete notifications that are over a day old. Should be a pretty simple part of the cleanup in the meetups.

[tometo-dev]

If needed for record keeping, just the meetup title and the organiser (with the date and time of the past meetup) can be written to a read-only #past-meetups channel

[kentcdodds]

That's a good idea. I was wondering about how to handle that 👍

Alternatively we could just edit the message to remove the mentions. Sometimes multiple messages are sent if it's too long though which may complicate things

[tometo-dev]

Keeping things separate can keep them organized in the long run. Notifications should ideally show notifications and once the event is over, remove it. If a user has to then look if what was covered in previous meetups, they can look in the respective channel.

This can also handle the multiple-message split of the notifications.

[marcosvega91]

I like the idea of @tsuki42. it could work very well !!