*: add "etcd_server_client_requests_total", tests

Signed-off-by: Gyuho Lee <leegyuho@amazon.com>

.words

@@ -30,6 +30,7 @@ etcd
 gRPC
 goroutine
 goroutines
+hasleader
 healthcheck
 hostname
 iff

clientv3/integration/kv_test.go

@@ -17,8 +17,10 @@ package integration
 import (
 	"bytes"
 	"context"
+	"fmt"
 	"os"
 	"reflect"
+	"strconv"
 	"strings"
 	"testing"
 	"time"
@@ -28,6 +30,7 @@ import (
 	"go.etcd.io/etcd/integration"
 	"go.etcd.io/etcd/mvcc/mvccpb"
 	"go.etcd.io/etcd/pkg/testutil"
+	"go.etcd.io/etcd/version"
 
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
@@ -208,6 +211,22 @@ func TestKVPutWithRequireLeader(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	cnt, err := clus.Members[0].Metric(
+		"etcd_server_client_requests_total",
+		`type="unary"`,
+		fmt.Sprintf(`client_api_version="%v"`, version.APIVersion),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cv, err := strconv.ParseInt(cnt, 10, 32)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cv < 1 { // >1 when retried
+		t.Fatalf("expected at least 1, got %q", cnt)
+	}
+
 	// clients may give timeout errors since the members are stopped; take
 	// the clients so that terminating the cluster won't complain
 	clus.Client(1).Close()

clientv3/integration/watch_test.go

@@ -20,6 +20,7 @@ import (
 	"math/rand"
 	"reflect"
 	"sort"
+	"strconv"
 	"testing"
 	"time"
 
@@ -29,6 +30,7 @@ import (
 	"go.etcd.io/etcd/integration"
 	mvccpb "go.etcd.io/etcd/mvcc/mvccpb"
 	"go.etcd.io/etcd/pkg/testutil"
+	"go.etcd.io/etcd/version"
 
 	"google.golang.org/grpc/metadata"
 )
@@ -839,6 +841,22 @@ func TestWatchWithRequireLeader(t *testing.T) {
 	if _, ok := <-chNoLeader; !ok {
 		t.Fatalf("expected response, got closed channel")
 	}
+
+	cnt, err := clus.Members[0].Metric(
+		"etcd_server_client_requests_total",
+		`type="stream"`,
+		fmt.Sprintf(`client_api_version="%v"`, version.APIVersion),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cv, err := strconv.ParseInt(cnt, 10, 32)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cv < 2 { // >2 when retried
+		t.Fatalf("expected at least 2, got %q", cnt)
+	}
 }
 
 // TestWatchWithFilter checks that watch filtering works.

etcdserver/api/v3rpc/interceptor.go

@@ -53,6 +53,12 @@ func newUnaryInterceptor(s *etcdserver.EtcdServer) grpc.UnaryServerInterceptor {
 
 		md, ok := metadata.FromIncomingContext(ctx)
 		if ok {
+			ver, vs := "unknown", md.Get(rpctypes.MetadataClientAPIVersionKey)
+			if len(vs) > 0 {
+				ver = vs[0]
+			}
+			clientRequests.WithLabelValues("unary", ver).Inc()
+
 			if ks := md[rpctypes.MetadataRequireLeaderKey]; len(ks) > 0 && ks[0] == rpctypes.MetadataHasLeader {
 				if s.Leader() == types.ID(raft.None) {
 					return nil, rpctypes.ErrGRPCNoLeader
@@ -184,6 +190,12 @@ func newStreamInterceptor(s *etcdserver.EtcdServer) grpc.StreamServerInterceptor
 
 		md, ok := metadata.FromIncomingContext(ss.Context())
 		if ok {
+			ver, vs := "unknown", md.Get(rpctypes.MetadataClientAPIVersionKey)
+			if len(vs) > 0 {
+				ver = vs[0]
+			}
+			clientRequests.WithLabelValues("stream", ver).Inc()
+
 			if ks := md[rpctypes.MetadataRequireLeaderKey]; len(ks) > 0 && ks[0] == rpctypes.MetadataHasLeader {
 				if s.Leader() == types.ID(raft.None) {
 					return rpctypes.ErrGRPCNoLeader
@@ -202,7 +214,6 @@ func newStreamInterceptor(s *etcdserver.EtcdServer) grpc.StreamServerInterceptor
 					smap.mu.Unlock()
 					cancel()
 				}()
-
 			}
 		}
 

etcdserver/api/v3rpc/metrics.go

@@ -39,10 +39,20 @@ var (
 	},
 		[]string{"Type", "API"},
 	)
+
+	clientRequests = prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: "etcd",
+		Subsystem: "server",
+		Name:      "client_requests_total",
+		Help:      "The total number of client requests per client version.",
+	},
+		[]string{"type", "client_api_version"},
+	)
 )
 
 func init() {
 	prometheus.MustRegister(sentBytes)
 	prometheus.MustRegister(receivedBytes)
 	prometheus.MustRegister(streamFailures)
+	prometheus.MustRegister(clientRequests)
 }

integration/cluster.go

@@ -1143,7 +1143,7 @@ func (m *member) Terminate(t testing.TB) {
 }
 
 // Metric gets the metric value for a member
-func (m *member) Metric(metricName string) (string, error) {
+func (m *member) Metric(metricName string, expectLabels ...string) (string, error) {
 	cfgtls := transport.TLSInfo{}
 	tr, err := transport.NewTimeoutTransport(cfgtls, time.Second, time.Second, time.Second)
 	if err != nil {
@@ -1161,9 +1161,20 @@ func (m *member) Metric(metricName string) (string, error) {
 	}
 	lines := strings.Split(string(b), "\n")
 	for _, l := range lines {
-		if strings.HasPrefix(l, metricName) {
-			return strings.Split(l, " ")[1], nil
+		if !strings.HasPrefix(l, metricName) {
+			continue
 		}
+		ok := true
+		for _, lv := range expectLabels {
+			if !strings.Contains(l, lv) {
+				ok = false
+				break
+			}
+		}
+		if !ok {
+			continue
+		}
+		return strings.Split(l, " ")[1], nil
 	}
 	return "", nil
 }