add metrics

README.md

@@ -18,13 +18,13 @@ Docker image `janos/bee`.
 Execute the command terminals to start `node 1`:
 
 ```sh
-bee start --api-addr :8501 --p2p-addr :30401
+bee start --api-addr :8501 --p2p-addr :30401 --debug-api-addr :6061
 ```
 
 Use one of the multiaddresses as bootnode for `node 2` in order to connect them:
 
 ```sh
-bee start --api-addr :8502 --p2p-addr :30402 --bootnode /ip4/127.0.0.1/tcp/30401/p2p/QmT4TNB4cKYanUjdYodw1Cns8cuVaRVo24hHNYcT7JjkTB
+bee start --api-addr :8502 --p2p-addr :30402 --debug-api-addr :6062 --bootnode /ip4/127.0.0.1/tcp/30401/p2p/QmT4TNB4cKYanUjdYodw1Cns8cuVaRVo24hHNYcT7JjkTB
 ```
 
 Use the last part of `node 1` multiaddress to ping it using `node 2` by making an HTTP request to `localhost:{PORT2}/pingpong/{ID1}` like:

cmd/bee/cmd/start.go

@@ -76,14 +76,15 @@ func (c *command) initStartCmd() (err error) {
 			}
 
 			// API server
+			apiService := api.New(api.Options{
+				P2P:      p2ps,
+				Pingpong: pingPong,
+			})
 			apiListener, err := net.Listen("tcp", c.config.GetString(optionNameAPIAddr))
 			if err != nil {
 				return fmt.Errorf("api listener: %w", err)
 			}
-			apiServer := &http.Server{Handler: api.New(api.Options{
-				P2P:      p2ps,
-				Pingpong: pingPong,
-			})}
+			apiServer := &http.Server{Handler: apiService}
 
 			go func() {
 				cmd.Println("api address:", apiListener.Addr())
@@ -93,20 +94,29 @@ func (c *command) initStartCmd() (err error) {
 				}
 			}()
 
-			// Debug API server
-			debugAPIListener, err := net.Listen("tcp", c.config.GetString(optionNameDebugAPIAddr))
-			if err != nil {
-				return fmt.Errorf("debug api listener: %w", err)
-			}
-			debugAPIServer := &http.Server{Handler: debugapi.New(debugapi.Options{})}
+			var debugAPIServer *http.Server
+			if addr := c.config.GetString(optionNameDebugAPIAddr); addr != "" {
+				// Debug API server
+				debugAPIService := debugapi.New(debugapi.Options{})
+				// register metrics from components
+				debugAPIService.MustRegisterMetrics(pingPong.Metrics()...)
+				debugAPIService.MustRegisterMetrics(apiService.Metrics()...)
+
+				debugAPIListener, err := net.Listen("tcp", addr)
+				if err != nil {
+					return fmt.Errorf("debug api listener: %w", err)
+				}
 
-			go func() {
-				cmd.Println("debug api address:", debugAPIListener.Addr())
+				debugAPIServer := &http.Server{Handler: debugAPIService}
 
-				if err := debugAPIServer.Serve(debugAPIListener); err != nil && err != http.ErrServerClosed {
-					log.Println("debug api server:", err)
-				}
-			}()
+				go func() {
+					cmd.Println("debug api address:", debugAPIListener.Addr())
+
+					if err := debugAPIServer.Serve(debugAPIListener); err != nil && err != http.ErrServerClosed {
+						log.Println("debug api server:", err)
+					}
+				}()
+			}
 
 			// Wait for termination or interrupt signals.
 			// We want to clean up things at the end.
@@ -135,8 +145,10 @@ func (c *command) initStartCmd() (err error) {
 					log.Println("api server shutdown:", err)
 				}
 
-				if err := debugAPIServer.Shutdown(ctx); err != nil {
-					log.Println("debug api server shutdown:", err)
+				if debugAPIServer != nil {
+					if err := debugAPIServer.Shutdown(ctx); err != nil {
+						log.Println("debug api server shutdown:", err)
+					}
 				}
 
 				if err := p2ps.Close(); err != nil {

go.mod

@@ -18,6 +18,7 @@ require (
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/multiformats/go-multiaddr v0.2.0
 	github.com/multiformats/go-multistream v0.1.0
+	github.com/prometheus/client_golang v1.3.0
 	github.com/spf13/cobra v0.0.5
 	github.com/spf13/viper v1.6.1
 	resenje.org/web v0.4.0

go.sum

@@ -13,6 +13,7 @@ github.com/alecthomas/units v0.0.0-20190717042225-c3de453c63f4/go.mod h1:ybxpYRF
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/btcsuite/btcd v0.0.0-20190213025234-306aecffea32/go.mod h1:DrZx5ec/dmnfpw9KyYoQyYo7d0KEvTkk/5M/vbZjAr8=
 github.com/btcsuite/btcd v0.0.0-20190523000118-16327141da8c/go.mod h1:3J08xEfcugPacsc34/LKRU2yO7YmuT8yt28J8k2+rrI=
@@ -28,7 +29,9 @@ github.com/btcsuite/snappy-go v0.0.0-20151229074030-0bdef8d06723/go.mod h1:8woku
 github.com/btcsuite/websocket v0.0.0-20150119174127-31079b680792/go.mod h1:ghJtEyQwv5/p4Mg4C0fgbePVuGr935/5ddU9Z3TmDRY=
 github.com/btcsuite/winsvc v1.0.0/go.mod h1:jsenWakMcC0zFBFurPLEAyrnc/teJEM1O46fmI40EZs=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+github.com/cespare/xxhash v1.1.0 h1:a6HrQnmkObjyL+Gs60czilIUGqrzKutQD6XZog3p+ko=
 github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
+github.com/cespare/xxhash/v2 v2.1.1 h1:6MnRN8NT7+YBpUIWxHtefFZOKTAPgGjpQSxqLNn0+qY=
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cheekybits/genny v1.0.0 h1:uGGa4nei+j20rOSeDeP5Of12XVm7TGUd4dJA9RDitfE=
 github.com/cheekybits/genny v1.0.0/go.mod h1:+tQajlRqAUrPI7DOSpB0XAqZYtQakVtB7wXkRAgjxjQ=
@@ -292,6 +295,7 @@ github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaO
 github.com/mattn/go-colorable v0.1.1/go.mod h1:FuOcm+DKB9mbwrcAfNl7/TZVBZ6rcnceauSikq3lYCQ=
 github.com/mattn/go-isatty v0.0.4/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
 github.com/mattn/go-isatty v0.0.5/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
+github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b/go.mod h1:01TrycV0kFyexm33Z7vhZRXopbI8J3TDReVlkTgMUxE=
 github.com/miekg/dns v1.1.12/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
@@ -369,20 +373,24 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v0.9.3/go.mod h1:/TN21ttK/J9q6uSwhBd54HahCDft0ttaMvbicHlPoso=
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
+github.com/prometheus/client_golang v1.3.0 h1:miYCvYqFXtl/J9FIy8eNpBfYthAEFg+Ys0XyUVEcDsc=
 github.com/prometheus/client_golang v1.3.0/go.mod h1:hJaj2vgQTGQmVCsAACORcieXFeDPbaTKGT+JTgUa3og=
 github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
 github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
+github.com/prometheus/client_model v0.1.0 h1:ElTg5tNp4DqfV7UQjDqv2+RJlNzsDtvNAWccbItceIE=
 github.com/prometheus/client_model v0.1.0/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/common v0.0.0-20181113130724-41aa239b4cce/go.mod h1:daVV7qP5qjZbuso7PdcryaAu0sAZbrN9i7WWcTMWvro=
 github.com/prometheus/common v0.4.0/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y86RQel1bk4=
 github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y86RQel1bk4=
 github.com/prometheus/common v0.6.0/go.mod h1:eBmuwkDJBwy6iBfxCBob6t6dR6ENT/y+J+Zk0j9GMYc=
+github.com/prometheus/common v0.7.0 h1:L+1lyG48J1zAQXA3RBX/nG/B3gjlHq0zTt2tlbJLyCY=
 github.com/prometheus/common v0.7.0/go.mod h1:DjGbpBbp5NYNiECxcL/VnbXCCaQpKd3tt26CguLLsqA=
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.0-20190507164030-5867b95ac084/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/procfs v0.0.3/go.mod h1:4A/X28fw3Fc593LaREMrKMqOKvUAntwMDaekg4FpcdQ=
+github.com/prometheus/procfs v0.0.8 h1:+fpWZdT24pJBiqJdAwYBjPSk+5YmQzYNPYzQsdzLkt8=
 github.com/prometheus/procfs v0.0.8/go.mod h1:7Qr8sr6344vo1JqZ6HhLceV9o3AJ1Ff+GxbHq6oeK9A=
 github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40TwIPHuXU=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=

pkg/api/api.go

@@ -5,11 +5,18 @@ import (
 
 	"github.com/janos/bee/pkg/p2p"
 	"github.com/janos/bee/pkg/pingpong"
+	"github.com/prometheus/client_golang/prometheus"
 )
 
+type Service interface {
+	http.Handler
+	Metrics() (cs []prometheus.Collector)
+}
+
 type server struct {
 	Options
 	http.Handler
+	metrics metrics
 }
 
 type Options struct {
@@ -17,9 +24,10 @@ type Options struct {
 	Pingpong *pingpong.Service
 }
 
-func New(o Options) http.Handler {
+func New(o Options) Service {
 	s := &server{
 		Options: o,
+		metrics: newMetrics(),
 	}
 
 	s.setupRouting()

pkg/api/metrics.go

+package api
+
+import (
+	"net/http"
+	"reflect"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type metrics struct {
+	// all metrics fields must be exported
+	// to be able to return them by Metrics()
+	// using reflection
+	RequestCount     prometheus.Counter
+	ResponseDuration prometheus.Histogram
+	PingRequestCount prometheus.Counter
+}
+
+func newMetrics() (m metrics) {
+	return metrics{
+		RequestCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "api_request_count",
+			Help: "Number of API requests.",
+		}),
+		ResponseDuration: prometheus.NewHistogram(prometheus.HistogramOpts{
+			Name:    "api_response_duration_seconds",
+			Help:    "Histogram of API response durations.",
+			Buckets: []float64{0.01, 0.1, 0.25, 0.5, 1, 2.5, 5, 10},
+		}),
+		PingRequestCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "api_ping_request_count",
+			Help: "Number HTTP API ping requests.",
+		}),
+	}
+}
+
+func (s *server) Metrics() (cs []prometheus.Collector) {
+	v := reflect.Indirect(reflect.ValueOf(s.metrics))
+	for i := 0; i < v.NumField(); i++ {
+		if !v.Field(i).CanInterface() {
+			continue
+		}
+		if u, ok := v.Field(i).Interface().(prometheus.Collector); ok {
+			cs = append(cs, u)
+		}
+	}
+	return cs
+}
+
+func (s *server) pageviewMetricsHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+		s.metrics.RequestCount.Inc()
+		h.ServeHTTP(w, r)
+		s.metrics.ResponseDuration.Observe(time.Since(start).Seconds())
+	})
+}

pkg/api/pingpong.go

@@ -17,6 +17,7 @@ func (s *server) pingpongHandler(w http.ResponseWriter, r *http.Request) {
 		fmt.Fprintln(w, "ping error", peerID, err)
 		return
 	}
+	s.metrics.PingRequestCount.Inc()
 
 	fmt.Fprintln(w, "RTT", rtt)
 }

pkg/api/router.go

@@ -20,6 +20,7 @@ func (s *server) setupRouting() {
 
 	s.Handler = web.ChainHandlers(
 		handlers.CompressHandler,
+		s.pageviewMetricsHandler,
 		web.FinalHandler(baseRouter),
 	)
 }

pkg/debugapi/debugapi.go

@@ -2,18 +2,28 @@ package debugapi
 
 import (
 	"net/http"
+
+	"github.com/prometheus/client_golang/prometheus"
 )
 
+type Service interface {
+	http.Handler
+	MustRegisterMetrics(cs ...prometheus.Collector)
+}
+
 type server struct {
 	Options
 	http.Handler
+
+	metricsRegistry *prometheus.Registry
 }
 
 type Options struct{}
 
-func New(o Options) http.Handler {
+func New(o Options) Service {
 	s := &server{
-		Options: o,
+		Options:         o,
+		metricsRegistry: newMetricsRegistry(),
 	}
 
 	s.setupRouting()

pkg/debugapi/metrics.go

+package debugapi
+
+import (
+	"github.com/janos/bee"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func newMetricsRegistry() (r *prometheus.Registry) {
+	r = prometheus.NewRegistry()
+
+	// register standard metrics
+	r.MustRegister(
+		prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}),
+		prometheus.NewGoCollector(),
+		prometheus.NewGauge(prometheus.GaugeOpts{
+			Name: "bee_info",
+			Help: "Bee information.",
+			ConstLabels: prometheus.Labels{
+				"version": bee.Version,
+			},
+		}),
+	)
+
+	return r
+}
+
+func (s *server) MustRegisterMetrics(cs ...prometheus.Collector) {
+	s.metricsRegistry.MustRegister(cs...)
+}

pkg/debugapi/router.go

@@ -6,12 +6,18 @@ import (
 	"net/http/pprof"
 
 	"github.com/gorilla/handlers"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"resenje.org/web"
 )
 
 func (s *server) setupRouting() {
 	internalBaseRouter := http.NewServeMux()
 
+	internalBaseRouter.Handle("/metrics", promhttp.InstrumentMetricHandler(
+		s.metricsRegistry,
+		promhttp.HandlerFor(s.metricsRegistry, promhttp.HandlerOpts{}),
+	))
+
 	internalRouter := http.NewServeMux()
 	internalBaseRouter.Handle("/", web.ChainHandlers(
 		handlers.CompressHandler,

pkg/pingpong/metrics.go

+package pingpong
+
+import (
+	"reflect"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type metrics struct {
+	// all metrics fields must be exported
+	// to be able to return them by Metrics()
+	// using reflection
+	PingSentCount     prometheus.Counter
+	PongSentCount     prometheus.Counter
+	PingReceivedCount prometheus.Counter
+	PongReceivedCount prometheus.Counter
+}
+
+func newMetrics() (m metrics) {
+	return metrics{
+		PingSentCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "pingpong_ping_sent_count",
+			Help: "Number ping requests sent.",
+		}),
+		PongSentCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "pingpong_pong_sent_count",
+			Help: "Number of pong responses sent.",
+		}),
+		PingReceivedCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "pingpong_ping_received_count",
+			Help: "Number ping requests received.",
+		}),
+		PongReceivedCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "pingpong_pong_received_count",
+			Help: "Number of pong responses received.",
+		}),
+	}
+}
+
+func (s *Service) Metrics() (cs []prometheus.Collector) {
+	v := reflect.Indirect(reflect.ValueOf(s.metrics))
+	for i := 0; i < v.NumField(); i++ {
+		if !v.Field(i).CanInterface() {
+			continue
+		}
+		if u, ok := v.Field(i).Interface().(prometheus.Collector); ok {
+			cs = append(cs, u)
+		}
+	}
+	return cs
+}

pkg/pingpong/pingpong.go

@@ -21,10 +21,14 @@ const (
 
 type Service struct {
 	streamer p2p.Streamer
+	metrics  metrics
 }
 
 func New(streamer p2p.Streamer) *Service {
-	return &Service{streamer: streamer}
+	return &Service{
+		streamer: streamer,
+		metrics:  newMetrics(),
+	}
 }
 
 func (s *Service) Protocol() p2p.ProtocolSpec {
@@ -54,6 +58,7 @@ func (s *Service) Handler(p p2p.Peer) {
 			return
 		}
 		log.Printf("got ping: %q\n", ping.Greeting)
+		s.metrics.PingReceivedCount.Inc()
 
 		if err := w.WriteMsg(&Pong{
 			Response: "{" + ping.Greeting + "}",
@@ -61,6 +66,7 @@ func (s *Service) Handler(p p2p.Peer) {
 			log.Printf("pingpong handler: write message: %v\n", err)
 			return
 		}
+		s.metrics.PongSentCount.Inc()
 	}
 }
 
@@ -81,6 +87,7 @@ func (s *Service) Ping(ctx context.Context, peerID string, msgs ...string) (rtt
 		}); err != nil {
 			return 0, fmt.Errorf("stream write: %w", err)
 		}
+		s.metrics.PingSentCount.Inc()
 
 		if err := r.ReadMsg(&pong); err != nil {
 			if err == io.EOF {
@@ -90,6 +97,7 @@ func (s *Service) Ping(ctx context.Context, peerID string, msgs ...string) (rtt
 		}
 
 		log.Printf("got pong: %q\n", pong.Response)
+		s.metrics.PongReceivedCount.Inc()
 	}
 	return time.Since(start) / time.Duration(len(msgs)), nil
 }