How to execute a function every n hours in server side swift?

Question

I'm looking for a Swift counterpart to Django's Celery which allows a function to execute every given amount of time.

I need a solution that works on server side Swift, meaning not all of Foundation is available, and something that's not for iOS / Mac.

I am using the Vapor framework.

I have answered this question [here](https://stackoverflow.com/questions/41898944/how-to-use-timer-in-vapor-server-side-swift/55539678#55539678) with a code snippet — Kerusan, Apr 05 '19 at 16:26

score 11 · Accepted Answer · answered Aug 10 '17 at 23:39

11

You have three main options.

For a timer managed within your server app (i.e. restarting the server resets your timers) you can use Dispatch:

import Dispatch
let timer = DispatchSource.makeTimerSource()
timer.setEventHandler() {
  // task
}
timer.scheduleRepeating(deadline: .now() + .seconds(3600), interval: .seconds(3600), leeway: .seconds(60))
timer.activate()

Similarly, you can use the third party Jobs package created by a Vapor contributor:

import Jobs
Jobs.add(interval: .hours(1)) {
  // task
}

If you want the function to be run at particular times of day independent of your server's uptime, there's no beating cron (or its relatives). Your cron job should either call a Vapor Command on the binary, or hit a protected URL-route with curl.

answered Aug 10 '17 at 23:39

tobygriffin

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do you know how to do this in vapor 3? – Nevin Jethmalani Jun 13 '18 at 04:42
@NevinJethmalani The top two options do not depend on a particular Vapor version and should work. – tobygriffin Jun 20 '18 at 02:25
Jobs looks interesting. It's concerning to me though that it hasn't received an update in 2 years. – Chris Prince Sep 10 '20 at 18:59
The Jobs package, although outdated a bit, still works very nicely on Vapor 4 – Farini Mar 25 '21 at 16:08

How to execute a function every n hours in server side swift?

1 Answers1