Enable prometheus in bootnode

internal/cli/bootnode.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"net"
+	"net/http"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -16,6 +17,8 @@ import (
 	"github.com/ethereum/go-ethereum/internal/cli/flagset"
 	"github.com/ethereum/go-ethereum/internal/cli/server"
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/metrics"
+	"github.com/ethereum/go-ethereum/metrics/prometheus"
 	"github.com/ethereum/go-ethereum/p2p/discover"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/nat"
@@ -26,14 +29,16 @@ import (
 type BootnodeCommand struct {
 	UI cli.Ui
 
-	listenAddr string
+	listenAddr     string
-	v5         bool
+	enableMetrics  bool
-	verbosity  int
+	prometheusAddr string
-	logLevel   string
+	v5             bool
-	nat        string
+	verbosity      int
-	nodeKey    string
+	logLevel       string
-	saveKey    string
+	nat            string
-	dryRun     bool
+	nodeKey        string
+	saveKey        string
+	dryRun         bool
 }
 
 // Help implements the cli.Command interface
@@ -60,6 +65,18 @@ func (b *BootnodeCommand) Flags() *flagset.Flagset {
 		Usage:   "listening address of bootnode (<ip>:<port>)",
 		Value:   &b.listenAddr,
 	})
+	flags.BoolFlag(&flagset.BoolFlag{
+		Name:    "metrics",
+		Usage:   "Enable metrics collection and reporting",
+		Value:   &b.enableMetrics,
+		Default: true,
+	})
+	flags.StringFlag(&flagset.StringFlag{
+		Name:    "prometheus-addr",
+		Default: "127.0.0.1:7071",
+		Usage:   "listening address of bootnode (<ip>:<port>)",
+		Value:   &b.prometheusAddr,
+	})
 	flags.BoolFlag(&flagset.BoolFlag{
 		Name:    "v5",
 		Default: false,
@@ -237,6 +254,25 @@ func (b *BootnodeCommand) Run(args []string) int {
 		}
 	}
 
+	if b.enableMetrics {
+		prometheusMux := http.NewServeMux()
+
+		prometheusMux.Handle("/debug/metrics/prometheus", prometheus.Handler(metrics.DefaultRegistry))
+
+		promServer := &http.Server{
+			Addr:    b.prometheusAddr,
+			Handler: prometheusMux,
+		}
+
+		go func() {
+			if err := promServer.ListenAndServe(); err != nil {
+				log.Error("Failure in running Prometheus server", "err", err)
+			}
+		}()
+
+		log.Info("Enabling metrics export to prometheus", "path", fmt.Sprintf("http://%s/debug/metrics/prometheus", b.prometheusAddr))
+	}
+
 	signalCh := make(chan os.Signal, 4)
 	signal.Notify(signalCh, os.Interrupt, syscall.SIGTERM, syscall.SIGHUP)