init

exporter.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"log"
+	"sync"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type TargetRunner struct {
+	name   string
+	host   string
+	config TargetSettings
+
+	history []float64
+	hidx    int
+	mu      sync.Mutex
+}
+
+func NewTargetRunner(name, host string, cfg TargetSettings) *TargetRunner {
+	return &TargetRunner{
+		name:    name,
+		host:    host,
+		config:  cfg,
+		history: make([]float64, cfg.HistorySize),
+	}
+}
+
+// Prometheus-Metrics
+var (
+	pingUp = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "ping_up",
+			Help: "Whether the last ping was successful (1) or not (0)",
+		},
+		[]string{"target"},
+	)
+	pingRTT = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "ping_rtt_seconds",
+			Help: "Last ping round trip time in seconds",
+		},
+		[]string{"target"},
+	)
+	pingRTTAvg = prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Name: "ping_rtt_seconds_avg",
+			Help: "Average ping round trip time in seconds (over history)",
+		},
+		[]string{"target"},
+	)
+	pingPacketsSent = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "ping_packets_sent_total",
+			Help: "Total number of ping packets sent",
+		},
+		[]string{"target"},
+	)
+	pingPacketsRecv = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "ping_packets_received_total",
+			Help: "Total number of ping packets received",
+		},
+		[]string{"target"},
+	)
+)
+
+func init() {
+	prometheus.MustRegister(pingUp, pingRTT, pingRTTAvg, pingPacketsSent, pingPacketsRecv)
+}
+
+func (t *TargetRunner) Run(stop <-chan struct{}) {
+	lbl := prometheus.Labels{"target": t.name}
+
+	ticker := time.NewTicker(t.config.Interval)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ticker.C:
+			pingPacketsSent.With(lbl).Inc()
+
+			res := doPing(t.host, PingOptions{
+				Timeout:     t.config.Timeout,
+				Size:        t.config.Size,
+				DisableIPv6: t.config.DisableIPv6,
+				DNSServer:   t.config.DNSServer,
+			})
+
+			if res.Alive {
+				pingUp.With(lbl).Set(1)
+				pingPacketsRecv.With(lbl).Inc()
+
+				sec := res.RTT.Seconds()
+				pingRTT.With(lbl).Set(sec)
+
+				avg := t.addToHistoryAndAvg(sec)
+				pingRTTAvg.With(lbl).Set(avg)
+			} else {
+				pingUp.With(lbl).Set(0)
+				// RTT nicht ändern oder auf 0 setzen?
+				pingRTT.With(lbl).Set(0)
+				log.Printf("ping to %s failed: %v", t.name, res.Err)
+			}
+		case <-stop:
+			return
+		}
+	}
+}
+
+func (t *TargetRunner) addToHistoryAndAvg(v float64) float64 {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+
+	if len(t.history) == 0 {
+		return v
+	}
+
+	t.history[t.hidx] = v
+	t.hidx = (t.hidx + 1) % len(t.history)
+
+	var sum float64
+	var cnt int
+	for _, x := range t.history {
+		if x > 0 {
+			sum += x
+			cnt++
+		}
+	}
+	if cnt == 0 {
+		return 0
+	}
+	return sum / float64(cnt)
+}