Go by Example: Tickers

Timers are for when you want to do something once in the future - tickers are for when you want to do something repeatedly at regular intervals. Here’s an example of a ticker that ticks periodically until we stop it.

package main
import "time"
import "fmt"
func main() {

Tickers use a similar mechanism to timers: a channel that is sent values. Here we’ll use the range builtin on the channel to iterate over the values as they arrive every 500ms.

	ticker := time.NewTicker(time.Millisecond * 500)
	go func() {
		for t := range ticker.C {
			fmt.Println("Tick at", t)
		}
	}()

Tickers can be stopped like timers. Once a ticker is stopped it won’t receive any more values on its channel. We’ll stop ours after 1500ms.

	time.Sleep(time.Millisecond * 1500)
	ticker.Stop()
	fmt.Println("Ticker stopped")
}

When we run this program the ticker should tick 3 times before we stop it.

$ go run tickers.go
Tick at 2012-09-23 11:29:56.487625 -0700 PDT
Tick at 2012-09-23 11:29:56.988063 -0700 PDT
Tick at 2012-09-23 11:29:57.488076 -0700 PDT
Ticker stopped

Previous example: Timers.

Next example: Worker Pools.