How to do work on a timer in a windows service

23 Oct 2015

I was building a windows service that needed to fire off a long running function every so often. I couldn’t use a Ticker since I wasn’t sure when the function would return. This is an example of how I ended up using a Timer to do this. Everytime a signal is received from the Timer, I make sure the timer is stopped, perform the long running task and then reset the Timer to fire again.

package main
import "github.com/kardianos/service"
import "time"

type program struct{
  exit chan struct{}
}

func longProcessingFunc(){
  time.Sleep(60 * time.Second)
}

func (p *program) Start(s service.Service) error{
  go p.run()
  return nil
}

func(p *program) Stop(s service.Service) error{
  close(p.exit)
}

func (p *program) run() error{
  ticker := time.NewTimer( 5 * time.Second)
  for{
      case <-ticker.C:
          ticker.Stop()
          //DO SOMETHING
          longProcessingFunc()
          ticker.Reset(5 * time.Second)
      case <-p.exit:
          ticker.Stop()
          return nil
      }
}

func main(){
  svcConfig := &service.Config{
      Name: "ServiceName"
      DisplayName:"ServiceDisplayName"
      Description:"ServiceDescription"}
  prg := &program{}
  s,err := service.New(prg,svcConfig)
  if err != nil{
      panic(err)
  }
  err = s.Run()
  if err != nil{
      panic(err)
  }
}