Add the user rpc counter (#22872)

Signed-off-by: SimFG <bang.fu@zilliz.com>

internal/metrics/proxy_metrics.go

@@ -232,6 +232,14 @@ var (
 			Name:      "hook_func_count",
 			Help:      "the hook function count",
 		}, []string{functionLabelName, fullMethodLabelName})
+
+	UserRPCCounter = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: milvusNamespace,
+			Subsystem: typeutil.ProxyRole,
+			Name:      "user_rpc_count",
+			Help:      "the rpc count of a user",
+		}, []string{usernameLabelName})
 )
 
 // RegisterProxy registers Proxy metrics
@@ -267,6 +275,7 @@ func RegisterProxy(registry *prometheus.Registry) {
 
 	registry.MustRegister(ProxyLimiterRate)
 	registry.MustRegister(ProxyHookFunc)
+	registry.MustRegister(UserRPCCounter)
 }
 
 // SetRateGaugeByRateType sets ProxyLimiterRate metrics.

internal/proxy/authentication_interceptor.go

@@ -4,11 +4,10 @@ import (
 	"context"
 	"strings"
 
-	"google.golang.org/grpc/metadata"
-
+	"github.com/milvus-io/milvus/internal/metrics"
 	"github.com/milvus-io/milvus/internal/util"
-
 	"github.com/milvus-io/milvus/internal/util/crypto"
+	"google.golang.org/grpc/metadata"
 )
 
 // validAuth validates the authentication
@@ -27,8 +26,11 @@ func validAuth(ctx context.Context, authorization []string) bool {
 	secrets := strings.SplitN(rawToken, util.CredentialSeperator, 2)
 	username := secrets[0]
 	password := secrets[1]
-
-	return passwordVerify(ctx, username, password, globalMetaCache)
+	isSuccess := passwordVerify(ctx, username, password, globalMetaCache)
+	if isSuccess {
+		metrics.UserRPCCounter.WithLabelValues(username).Inc()
+	}
+	return isSuccess
 }
 
 func validSourceID(ctx context.Context, authorization []string) bool {