Fix missing metrics and verify metrics are not lost

Signed-off-by: Davanum Srinivas <[email protected]>

server/config/config.go

@@ -211,6 +211,8 @@ type ServerConfig struct {
 
 	// ServerFeatureGate is a server level feature gate
 	ServerFeatureGate featuregate.FeatureGate
+
+	Metrics string
 }
 
 // VerifyBootstrap sanity-checks the initial config for bootstrap case

server/embed/etcd.go

@@ -31,7 +31,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/prometheus/client_golang/prometheus"
 	"github.com/soheilhy/cmux"
 	"go.uber.org/zap"
 	"google.golang.org/grpc"
@@ -227,6 +226,7 @@ func StartEtcd(inCfg *Config) (e *Etcd, err error) {
 		V2Deprecation:                                 cfg.V2DeprecationEffective(),
 		ExperimentalLocalAddress:                      cfg.InferLocalAddr(),
 		ServerFeatureGate:                             cfg.ServerFeatureGate,
+		Metrics:                                       cfg.Metrics,
 	}
 
 	if srvcfg.ExperimentalEnableDistributedTracing {
@@ -844,18 +844,6 @@ func (e *Etcd) createMetricsListener(murl url.URL) (net.Listener, error) {
 }
 
 func (e *Etcd) serveMetrics() (err error) {
-	if e.cfg.Metrics == "extensive" {
-		var opts prometheus.HistogramOpts
-		serverHandledHistogram := prometheus.NewHistogramVec(
-			opts,
-			[]string{"grpc_type", "grpc_service", "grpc_method"},
-		)
-		err := prometheus.Register(serverHandledHistogram)
-		if err != nil {
-			e.GetLogger().Error("setting up prometheus metrics failed.", zap.Error(err))
-		}
-	}
-
 	if len(e.cfg.ListenMetricsUrls) > 0 {
 		metricsMux := http.NewServeMux()
 		etcdhttp.HandleMetrics(metricsMux)

server/etcdserver/api/v3rpc/grpc.go

@@ -15,8 +15,11 @@
 package v3rpc
 
 import (
+	"context"
 	"crypto/tls"
 	"math"
+	"strings"
+	"time"
 
 	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-middleware/providers/prometheus"
 	"github.com/prometheus/client_golang/prometheus"
@@ -34,6 +37,14 @@ const (
 	maxSendBytes = math.MaxInt32
 )
 
+func splitMethodName(fullMethodName string) (string, string) {
+	fullMethodName = strings.TrimPrefix(fullMethodName, "/") // remove leading slash
+	if i := strings.Index(fullMethodName, "/"); i >= 0 {
+		return fullMethodName[:i], fullMethodName[i+1:]
+	}
+	return "unknown", "unknown"
+}
+
 func Server(s *etcdserver.EtcdServer, tls *tls.Config, interceptor grpc.UnaryServerInterceptor, gopts ...grpc.ServerOption) *grpc.Server {
 	var opts []grpc.ServerOption
 	opts = append(opts, grpc.CustomCodec(&codec{}))
@@ -57,6 +68,32 @@ func Server(s *etcdserver.EtcdServer, tls *tls.Config, interceptor grpc.UnarySer
 		newStreamInterceptor(s),
 		serverMetrics.StreamServerInterceptor(),
 	}
+	if s.Cfg.Metrics == "extensive" {
+		serverHandledHistogram := prometheus.NewHistogramVec(
+			prometheus.HistogramOpts{
+				Name:    "grpc_server_handling_seconds",
+				Help:    "Histogram of response latency (seconds) of gRPC that had been application-level handled by the server.",
+				Buckets: prometheus.DefBuckets,
+			},
+			[]string{"grpc_type", "grpc_service", "grpc_method"},
+		)
+		prometheus.Register(serverHandledHistogram)
+
+		startTime := time.Now()
+		chainUnaryInterceptors = append(chainUnaryInterceptors,
+			func(ctx context.Context, req any, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp any, err error) {
+				resp, err = handler(ctx, req)
+				grpcService, grpcMethod := splitMethodName(info.FullMethod)
+				serverHandledHistogram.WithLabelValues("unary", grpcService, grpcMethod).Observe(time.Since(startTime).Seconds())
+				return resp, err
+			})
+		chainStreamInterceptors = append(chainStreamInterceptors, func(srv interface{}, ss grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
+			err := handler(srv, ss)
+			grpcService, grpcMethod := splitMethodName(info.FullMethod)
+			serverHandledHistogram.WithLabelValues("stream", grpcService, grpcMethod).Observe(time.Since(startTime).Seconds())
+			return err
+		})
+	}
 
 	if s.Cfg.ExperimentalEnableDistributedTracing {
 		chainUnaryInterceptors = append(chainUnaryInterceptors, otelgrpc.UnaryServerInterceptor(s.Cfg.ExperimentalTracerOptions...))

tests/framework/integration/cluster.go

@@ -175,6 +175,7 @@ type ClusterConfig struct {
 	ExperimentalMaxLearners     int
 	DisableStrictReconfigCheck  bool
 	CorruptCheckTime            time.Duration
+	Metrics                     string
 }
 
 type Cluster struct {
@@ -292,6 +293,7 @@ func (c *Cluster) MustNewMember(t testutil.TB) *Member {
 			ExperimentalMaxLearners:     c.Cfg.ExperimentalMaxLearners,
 			DisableStrictReconfigCheck:  c.Cfg.DisableStrictReconfigCheck,
 			CorruptCheckTime:            c.Cfg.CorruptCheckTime,
+			Metrics:                     c.Cfg.Metrics,
 		})
 	m.DiscoveryURL = c.Cfg.DiscoveryURL
 	return m
@@ -617,6 +619,7 @@ type MemberConfig struct {
 	ExperimentalMaxLearners     int
 	DisableStrictReconfigCheck  bool
 	CorruptCheckTime            time.Duration
+	Metrics                     string
 }
 
 // MustNewMember return an inited member with the given name. If peerTLS is
@@ -731,6 +734,7 @@ func MustNewMember(t testutil.TB, mcfg MemberConfig) *Member {
 	if mcfg.ExperimentalMaxLearners != 0 {
 		m.ExperimentalMaxLearners = mcfg.ExperimentalMaxLearners
 	}
+	m.Metrics = mcfg.Metrics
 	m.V2Deprecation = config.V2_DEPR_DEFAULT
 	m.GRPCServerRecorder = &grpctesting.GRPCRecorder{}
 

tests/integration/clientv3/metrics_test.go

@@ -181,3 +181,120 @@ func getHTTPBodyAsLines(t *testing.T, url string) []string {
 	resp.Body.Close()
 	return lines
 }
+
+func TestAllMetricsGenerated(t *testing.T) {
+	integration2.BeforeTest(t)
+
+	var (
+		addr = "localhost:27989"
+		ln   net.Listener
+	)
+
+	srv := &http.Server{Handler: promhttp.Handler()}
+	srv.SetKeepAlivesEnabled(false)
+
+	ln, err := transport.NewUnixListener(addr)
+	if err != nil {
+		t.Errorf("Error: %v occurred while listening on addr: %v", err, addr)
+	}
+
+	donec := make(chan struct{})
+	defer func() {
+		ln.Close()
+		<-donec
+	}()
+
+	// listen for all Prometheus metrics
+	go func() {
+		defer close(donec)
+
+		serr := srv.Serve(ln)
+		if serr != nil && !transport.IsClosedConnError(serr) {
+			t.Errorf("Err serving http requests: %v", serr)
+		}
+	}()
+
+	url := "unix://" + addr + "/metrics"
+
+	clus := integration2.NewCluster(t, &integration2.ClusterConfig{Size: 1, Metrics: "extensive"})
+	defer clus.Terminate(t)
+
+	clientMetrics := grpcprom.NewClientMetrics()
+	prometheus.Register(clientMetrics)
+
+	cfg := clientv3.Config{
+		Endpoints: []string{clus.Members[0].GRPCURL},
+		DialOptions: []grpc.DialOption{
+			grpc.WithUnaryInterceptor(clientMetrics.UnaryClientInterceptor()),
+			grpc.WithStreamInterceptor(clientMetrics.StreamClientInterceptor()),
+		},
+	}
+	cli, cerr := integration2.NewClient(t, cfg)
+	if cerr != nil {
+		t.Fatal(cerr)
+	}
+	defer cli.Close()
+
+	// Perform some operations to generate metrics
+	wc := cli.Watch(context.Background(), "foo")
+	_, err = cli.Put(context.Background(), "foo", "bar")
+	if err != nil {
+		t.Errorf("Error putting value in key store")
+	}
+
+	// consume watch response
+	select {
+	case <-wc:
+	case <-time.After(10 * time.Second):
+		t.Error("Timeout occurred for getting watch response")
+	}
+
+	// Define the expected list of metrics
+	expectedMetrics := []string{
+		"grpc_server_handled_total",
+		"grpc_server_msg_received_total",
+		"grpc_server_msg_sent_total",
+		"grpc_server_started_total",
+		"grpc_server_handling_seconds_bucket",
+		"grpc_server_handling_seconds_count",
+		"grpc_server_handling_seconds_sum",
+		"grpc_server_handling_seconds",
+	}
+
+	// Get the list of generated metrics
+	generatedMetrics := getMetricsList(t, url)
+
+	for _, metric := range expectedMetrics {
+		if !contains(generatedMetrics, metric) {
+			t.Errorf("Expected metric %s not found in generated metrics", metric)
+		}
+	}
+}
+
+func getMetricsList(t *testing.T, url string) []string {
+	lines := getHTTPBodyAsLines(t, url)
+	metrics := make(map[string]struct{})
+	for _, line := range lines {
+		if strings.Contains(line, "{") {
+			metric := line[:strings.Index(line, "{")]
+			metrics[metric] = struct{}{}
+		} else {
+			metric := line[:strings.Index(line, " ")]
+			metrics[metric] = struct{}{}
+		}
+	}
+	var metricList []string
+	for metric := range metrics {
+		metricList = append(metricList, metric)
+	}
+	return metricList
+}
+
+func contains(slice []string, item string) bool {
+	for _, s := range slice {
+		if s == item {
+			return true
+		}
+	}
+	return false
+}