Function withExponentialBackoffAndJitter

ch09/backoff-simulator/main.go:136–152

Using withExponentialBackoff as the backoff function sends retries initially with a 1-second delay, but doubling after each attempt to a maximum delay of 1-minute. Each backoff time gets an additional

()

// initially with a 1-second delay, but doubling after each attempt to
// a maximum delay of 1-minute. Each backoff time gets an additional
func withExponentialBackoffAndJitter() string {
	res, err := sendRequest()
	base, cap := time.Second, time.Minute

	for backoff := base; err != nil; backoff <<= 1 {
		if backoff > cap {
			backoff = cap
		}

		jitter := rand.Int63n(int64(backoff * 3))
		sleep := base + time.Duration(jitter)
		time.Sleep(sleep)
		res, err = sendRequest()
	}

	return res
}

// sendRequest simulates sending a request. It always returns an
// error after a short delay.