func Periodic()

in timed/timed.go [67:91]

• 20 lines of code
• 6 McCabe index (conditional complexity)

func Periodic(ctx canceler, period time.Duration, fn func() error) error {
	ticker := time.NewTicker(period)
	defer ticker.Stop()

	done := ctx.Done()
	for {
		// always check for cancel first, to not accidentally trigger another run if
		// the context is already cancelled, but we have already received another
		// ticker signal
		select {
		case <-done:
			return ctx.Err()
		default:
		}

		select {
		case <-ticker.C:
			if err := fn(); err != nil {
				return err
			}
		case <-done:
			return ctx.Err()
		}
	}
}