metrics

cmd/httpserver/main.go

@@ -2,11 +2,14 @@ package main
 
 import (
 	"log"
+	"net/http"
+	"net/http/pprof"
 	"os"
 	"os/signal"
 	"syscall"
 	"time"
 
+	"github.com/VictoriaMetrics/metrics"
 	"github.com/flashbots/orderflow-proxy/common"
 	"github.com/flashbots/orderflow-proxy/proxy"
 	"github.com/google/uuid"
@@ -17,7 +20,7 @@ var flags []cli.Flag = []cli.Flag{
 	&cli.StringFlag{
 		Name:  "metrics-addr",
 		Value: "127.0.0.1:8090",
-		Usage: "address to listen on for Prometheus metrics",
+		Usage: "address to listen on for Prometheus metrics (metrics are served on $metrics-addr/metrics)",
 	},
 	&cli.BoolFlag{
 		Name:  "log-json",
@@ -42,7 +45,7 @@ var flags []cli.Flag = []cli.Flag{
 	&cli.BoolFlag{
 		Name:  "pprof",
 		Value: false,
-		Usage: "enable pprof debug endpoint",
+		Usage: "enable pprof debug endpoint (pprof is served on $metrics-addr/debug/pprof/*)",
 	},
 	&cli.StringFlag{
 		Name:  "listen-addr",
@@ -77,8 +80,6 @@ func main() {
 		Usage: "Serve API, and metrics",
 		Flags: flags,
 		Action: func(cCtx *cli.Context) error {
-			_ = cCtx.String("metrics-addr")
-			_ = cCtx.Bool("pprof")
 			logJSON := cCtx.Bool("log-json")
 			logDebug := cCtx.Bool("log-debug")
 			logUID := cCtx.Bool("log-uid")
@@ -99,6 +100,34 @@ func main() {
 			exit := make(chan os.Signal, 1)
 			signal.Notify(exit, os.Interrupt, syscall.SIGTERM)
 
+			// metrics server
+			go func() {
+				metricsAddr := cCtx.String("metrics-addr")
+				usePprof := cCtx.Bool("pprof")
+				metricsMux := http.NewServeMux()
+				metricsMux.HandleFunc("/metrics", func(w http.ResponseWriter, r *http.Request) {
+					metrics.WritePrometheus(w, true)
+				})
+				if usePprof {
+					metricsMux.Handle("/debug/pprof/", http.HandlerFunc(pprof.Index))
+					metricsMux.Handle("/debug/pprof/cmdline", http.HandlerFunc(pprof.Cmdline))
+					metricsMux.Handle("/debug/pprof/profile", http.HandlerFunc(pprof.Profile))
+					metricsMux.Handle("/debug/pprof/symbol", http.HandlerFunc(pprof.Symbol))
+					metricsMux.Handle("/debug/pprof/trace", http.HandlerFunc(pprof.Trace))
+				}
+
+				metricsServer := &http.Server{
+					Addr:              metricsAddr,
+					ReadHeaderTimeout: 5 * time.Second,
+					Handler:           metricsMux,
+				}
+
+				err := metricsServer.ListenAndServe()
+				if err != nil {
+					log.Error("Failed to start metrics server", "err", err)
+				}
+			}()
+
 			builderEndpoint := cCtx.String("builder-endpoint")
 			listedAddr := cCtx.String("listen-addr")
 			certDuration := cCtx.Duration("cert-duration")

go.mod

@@ -17,6 +17,7 @@ require (
 )
 
 require (
+	github.com/VictoriaMetrics/metrics v1.35.1 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/bits-and-blooms/bitset v1.13.0 // indirect
 	github.com/btcsuite/btcd/btcec/v2 v2.3.4 // indirect
@@ -42,6 +43,8 @@ require (
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/supranational/blst v0.3.13 // indirect
+	github.com/valyala/fastrand v1.1.0 // indirect
+	github.com/valyala/histogram v1.2.0 // indirect
 	github.com/xrash/smetrics v0.0.0-20240312152122-5f08fbb34913 // indirect
 	go.opentelemetry.io/otel v1.21.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.21.0 // indirect

go.sum

@@ -1,3 +1,5 @@
+github.com/VictoriaMetrics/metrics v1.35.1 h1:o84wtBKQbzLdDy14XeskkCZih6anG+veZ1SwJHFGwrU=
+github.com/VictoriaMetrics/metrics v1.35.1/go.mod h1:r7hveu6xMdUACXvB8TYdAj8WEsKzWB0EkpJN+RDtOf8=
 github.com/benbjohnson/clock v1.3.0 h1:ip6w0uFQkncKQ979AypyG0ER7mqUSBdKLOgAle/AT8A=
 github.com/benbjohnson/clock v1.3.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
@@ -82,6 +84,10 @@ github.com/supranational/blst v0.3.13 h1:AYeSxdOMacwu7FBmpfloBz5pbFXDmJL33RuwnKt
 github.com/supranational/blst v0.3.13/go.mod h1:jZJtfjgudtNl4en1tzwPIV3KjUnQUvG3/j+w+fVonLw=
 github.com/urfave/cli/v2 v2.27.2 h1:6e0H+AkS+zDckwPCUrZkKX38mRaau4nL2uipkJpbkcI=
 github.com/urfave/cli/v2 v2.27.2/go.mod h1:g0+79LmHHATl7DAcHO99smiR/T7uGLw84w8Y42x+4eM=
+github.com/valyala/fastrand v1.1.0 h1:f+5HkLW4rsgzdNoleUOB69hyT9IlD2ZQh9GyDMfb5G8=
+github.com/valyala/fastrand v1.1.0/go.mod h1:HWqCzkrkg6QXT8V2EXWvXCoow7vLwOFN002oeRzjapQ=
+github.com/valyala/histogram v1.2.0 h1:wyYGAZZt3CpwUiIb9AU/Zbllg1llXyrtApRS815OLoQ=
+github.com/valyala/histogram v1.2.0/go.mod h1:Hb4kBwb4UxsaNbbbh+RRz8ZR6pdodR57tzWUS3BUzXY=
 github.com/xrash/smetrics v0.0.0-20240312152122-5f08fbb34913 h1:+qGGcbkzsfDQNPPe9UDgpxAWQrhbbBXOYJFQDq/dtJw=
 github.com/xrash/smetrics v0.0.0-20240312152122-5f08fbb34913/go.mod h1:4aEEwZQutDLsQv2Deui4iYQ6DWTxR14g6m8Wv88+Xqk=
 go.opentelemetry.io/contrib/instrumentation/runtime v0.46.1 h1:m9ReioVPIffxjJlGNRd0d5poy+9oTro3D+YbiEzUDOc=

metrics/metrics.go

@@ -0,0 +1,11 @@
+package metrics
+
+import "github.com/VictoriaMetrics/metrics"
+
+var (
+	totalRequestReceived = metrics.NewCounter("requests_total")
+)
+
+func IncRequestsReceived() {
+	totalRequestReceived.Inc()
+}

proxy/proxy.go

@@ -11,6 +11,7 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/flashbots/orderflow-proxy/metrics"
 )
 
 type Config struct {
@@ -38,6 +39,7 @@ func New(config Config) (*Proxy, error) {
 }
 
 func (prx *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	metrics.IncRequestsReceived()
 	body, err := io.ReadAll(r.Body)
 	if err != nil {
 		return