add libp2p metrics for connections and streams

cmd/bee/cmd/start.go

@@ -99,6 +99,7 @@ func (c *command) initStartCmd() (err error) {
 				// Debug API server
 				debugAPIService := debugapi.New(debugapi.Options{})
 				// register metrics from components
+				debugAPIService.MustRegisterMetrics(p2ps.Metrics()...)
 				debugAPIService.MustRegisterMetrics(pingPong.Metrics()...)
 				debugAPIService.MustRegisterMetrics(apiService.Metrics()...)
 

pkg/p2p/libp2p/libp2p.go

@@ -27,6 +27,7 @@ var _ p2p.Service = new(Service)
 
 type Service struct {
 	host    host.Host
+	metrics metrics
 }
 
 type Options struct {
@@ -129,7 +130,10 @@ func New(ctx context.Context, o Options) (*Service, error) {
 		return nil, fmt.Errorf("autonat: %w", err)
 	}
 
-	s := &Service{host: h}
+	s := &Service{
+		host:    h,
+		metrics: newMetrics(),
+	}
 
 	// TODO: be more resilient on connection errors and connect in parallel
 	for _, a := range o.Bootnodes {
@@ -143,6 +147,10 @@ func New(ctx context.Context, o Options) (*Service, error) {
 		}
 	}
 
+	h.Network().SetConnHandler(func(_ network.Conn) {
+		s.metrics.HandledConnectionCount.Inc()
+	})
+
 	return s, nil
 }
 
@@ -153,10 +161,11 @@ func (s *Service) AddProtocol(p p2p.ProtocolSpec) (err error) {
 		if err != nil {
 			return fmt.Errorf("match semver %s: %w", id, err)
 		}
-		s.host.SetStreamHandlerMatch(id, matcher, func(s network.Stream) {
+		s.host.SetStreamHandlerMatch(id, matcher, func(stream network.Stream) {
+			s.metrics.HandledStreamCount.Inc()
 			ss.Handler(p2p.Peer{
-				Addr:   s.Conn().RemoteMultiaddr(),
-				Stream: s,
+				Addr:   stream.Conn().RemoteMultiaddr(),
+				Stream: stream,
 			})
 		})
 	}
@@ -189,6 +198,8 @@ func (s *Service) Connect(ctx context.Context, addr ma.Multiaddr) (peerID string
 		return "", err
 	}
 
+	s.metrics.CreatedConnectionCount.Inc()
+
 	return info.ID.String(), nil
 }
 
@@ -205,6 +216,7 @@ func (s *Service) NewStream(ctx context.Context, peerID, protocolName, streamNam
 		}
 		return nil, fmt.Errorf("create stream %q to %q: %w", swarmStreamName, peerID, err)
 	}
+	s.metrics.CreatedStreamCount.Inc()
 	return st, nil
 }
 

pkg/p2p/libp2p/metrics.go

+package libp2p
+
+import (
+	m "github.com/janos/bee/pkg/metrics"
+	"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
+	CreatedConnectionCount prometheus.Counter
+	HandledConnectionCount prometheus.Counter
+	CreatedStreamCount     prometheus.Counter
+	HandledStreamCount     prometheus.Counter
+}
+
+func newMetrics() (m metrics) {
+	return metrics{
+		CreatedConnectionCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "libp2p_created_connection_count",
+			Help: "Number of initiated outgoing libp2p connections.",
+		}),
+		HandledConnectionCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "libp2p_handled_connection_count",
+			Help: "Number of handled incoming libp2p connections.",
+		}),
+		CreatedStreamCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "libp2p_created_stream_count",
+			Help: "Number of initiated outgoing libp2p streams.",
+		}),
+		HandledStreamCount: prometheus.NewCounter(prometheus.CounterOpts{
+			Name: "libp2p_handled_stream_count",
+			Help: "Number of handled incoming libp2p streams.",
+		}),
+	}
+}
+
+func (s *Service) Metrics() []prometheus.Collector {
+	return m.PrometheusCollectorsFromFields(s.metrics)
+}