node_exporter/collector/ntp.go
Julius Volz efcce45c90 Make collector-specific flags consistent with others.
This puts all collector-specific flags into their own namespace under
"collector.<collector-name>", and moves from camel case to dashes, which
is the standard in Prometheus land now.
2015-02-18 18:42:39 +01:00

54 lines
1.2 KiB
Go

// +build !nontp
package collector
import (
"flag"
"fmt"
"time"
"github.com/beevik/ntp"
"github.com/golang/glog"
"github.com/prometheus/client_golang/prometheus"
)
var (
ntpServer = flag.String("collector.ntp.server", "", "NTP server to use for ntp collector.")
)
type ntpCollector struct {
drift prometheus.Gauge
}
func init() {
Factories["ntp"] = NewNtpCollector
}
// Takes a config struct and prometheus registry and returns a new Collector exposing
// the offset between ntp and the current system time.
func NewNtpCollector(config Config) (Collector, error) {
if *ntpServer == "" {
return nil, fmt.Errorf("No NTP server specifies, see --ntpServer")
}
return &ntpCollector{
drift: prometheus.NewGauge(prometheus.GaugeOpts{
Namespace: Namespace,
Name: "ntp_drift_seconds",
Help: "Time between system time and ntp time.",
}),
}, nil
}
func (c *ntpCollector) Update(ch chan<- prometheus.Metric) (err error) {
t, err := ntp.Time(*ntpServer)
if err != nil {
return fmt.Errorf("Couldn't get ntp drift: %s", err)
}
drift := t.Sub(time.Now())
glog.V(1).Infof("Set ntp_drift_seconds: %f", drift.Seconds())
c.drift.Set(drift.Seconds())
c.drift.Collect(ch)
return err
}