timeticker.go

var cache map[string]interface{}

func main() {
 ticker = time.NewTicker(3 * time.Second)
 defer ticker.Stop() // stop the ticker

 updaterChan = make(chan struct{})
 defer close(updaterChan) // close the channel

 // ...

 // launch a go routine to update the cache in the background
 go startUpdaterDaemon(ticker, updaterChan)
}

// startUpdaterDaemon is running in background
func startUpdaterDaemon(ticker *time.Ticker, updaterChan chan struct{}) {
  for {
    select {
      case <- ticker.C:
        // update cache
        // ...
      case <-updaterChan:
       // stop the daemon
       return                         
    }
  }
}