Background Task with autokilling itself and repeated action each N minutes

All fairly trivial with a GenServer, you can even send back yourself a message with a timeout (it only arrives if no other messages have arrived) or always in some-odd minutes regardless of any other messages (send_after).

You can do it with Task by using send_after though, but a GenServer really sounds best for this task as it does not sound like a one-off.

For some yes, for others no. We need to be careful with those sentences because they may discourage conversation. If something is trivial and someone doesn’t understand it, they may think it is their fault after all.

In any case, you are right, so thanks for pointing to the right direction. @washeku please see the following example as a starting point: http://stackoverflow.com/questions/32085258/how-to-run-some-code-every-few-hours-in-phoenix-framework

if it is not clear, please ask! I am sure @OvermindDL1, myself and others will be happy to help!

how should I specify the N minutes over the course of which it’ll be alive?
How can I make it to poll a state of an application once a minute?
how to make it terminate itself?

If a GenServer I’d do a send_after to send a kill message to self() after whatever N minutes, along with a handle that when it receives that message then it dies.

In a GenServer I’d either have it set an internal timeout as all callbacks in a GenServer can take (except terminate for obvious reasons ^.^) and just have it keep bouncing or use send_after again to send a ‘time to poll’ message, where you poll and then call send_after again based on the response.

Based on what condition? In a GenServer you just return {:stop, :normal} to do a normal non-error terminate.

how to do that?

With send_after, something like:

def init(args) do
  killSelfTime = args.death_minutes * 1000 * 60 # send_after wants milliseconds
  Process.send_after(self(), :kill_self, killSelfTime)
  state = encodeWhateverYouWantToDoHere(args)
  {:ok, state}
end

def handle_info(:kill_self, state) do
  cleanup()
  {:stop, :normal}
end

defp cleanup() do
  # If you need to do something else like cancel some pending function or un-register with
  # another server or something
end

I think handle_info callback should return {:stop, :normal, state}.

Possibly, I was just going from memory so that is very likely and makes sense. ^.^

thanks, I’ll try that out.

on a status which returns some console application I’ve mentioned.