integration/cluster.go
func (m *member) Metric(metricName string) (string, error) {
	cfgtls := transport.TLSInfo{}
	tr, err := transport.NewTimeoutTransport(cfgtls, time.Second, time.Second, time.Second)
	if err != nil {
		return "", err
	}
	cli := &http.Client{Transport: tr}
	resp, err := cli.Get(m.ClientURLs[0].String() + "/metrics")
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()
	b, rerr := ioutil.ReadAll(resp.Body)
	if rerr != nil {
		return "", rerr
	}
	lines := strings.Split(string(b), "\n")
	for _, l := range lines {
		if strings.HasPrefix(l, metricName) {
			return strings.Split(l, " ")[1], nil
		}
	}
	return "", nil
}
func (m *member) Metric(metricName string) (string, error) {
	cfgtls := transport.TLSInfo{}
	tr, err := transport.NewTimeoutTransport(cfgtls, time.Second, time.Second, time.Second)
	if err != nil {
		return "", err
	}
	cli := &http.Client{Transport: tr}
	resp, err := cli.Get(m.ClientURLs[0].String() + "/metrics")
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()
	b, rerr := ioutil.ReadAll(resp.Body)
	if rerr != nil {
		return "", rerr
	}
	lines := strings.Split(string(b), "\n")
	for _, l := range lines {
		if strings.HasPrefix(l, metricName) {
			return strings.Split(l, " ")[1], nil
		}
	}
	return "", nil
}
// Metric gets the metric value for a member