Added a check to log a warning if some labels are used in metric defi…

…nition

apis/flowmetrics/v1alpha1/flowmetric_webhook.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/netobserv/network-observability-operator/controllers/constants"
 	"github.com/netobserv/network-observability-operator/pkg/helper"
 
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
@@ -61,6 +62,25 @@ func (r *FlowMetricWebhook) ValidateDelete(_ context.Context, _ runtime.Object)
 	return nil, nil
 }
 
+func labelIsHighCardinality(label string) bool {
+	for _, hLabel := range constants.MetricHighCardinalityLabels {
+		if label == hLabel {
+			return true
+		}
+	}
+	return false
+}
+
+func checkFlowMetricCartinality(fMetric *FlowMetric) {
+	for _, label := range fMetric.Spec.Labels {
+		if labelIsHighCardinality(label) {
+			//No warning level logging as info since it is not an error
+			flowmetriclog.Info("Warning: metric label has high cardinality, please limit it by using some filters", "labelName", label)
+			return
+		}
+	}
+}
+
 func validateFlowMetric(_ context.Context, fMetric *FlowMetric) error {
 	var str []string
 	var allErrs field.ErrorList
@@ -95,5 +115,6 @@ func validateFlowMetric(_ context.Context, fMetric *FlowMetric) error {
 			schema.GroupKind{Group: GroupVersion.Group, Kind: FlowMetric{}.Kind},
 			fMetric.Name, allErrs)
 	}
+	checkFlowMetricCartinality(fMetric)
 	return nil
 }

controllers/constants/constants.go

@@ -54,3 +54,4 @@ var EnvNoHTTP2 = corev1.EnvVar{
 	Name:  "GODEBUG",
 	Value: "http2server=0",
 }
+var MetricHighCardinalityLabels = []string{"DstAddr", "DstK8S_Name", "DstMac", "SrcAddr", "SrcK8S_Name", "SrcMac"}