feat: support extending label metric allowlist

Author: rexagod

pkg/manifests/manifests.go

@@ -49,6 +49,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/sets"
 	auditv1 "k8s.io/apiserver/pkg/apis/audit/v1"
 	apiregistrationv1 "k8s.io/kube-aggregator/pkg/apis/apiregistration/v1"
+	ksmpkg "k8s.io/kube-state-metrics/v2/pkg/options"
 	"k8s.io/utils/ptr"
 	k8syaml "sigs.k8s.io/yaml"
 
@@ -767,6 +768,19 @@ func (f *Factory) KubeStateMetricsDeployment(enableCRSMetrics bool) (*appsv1.Dep
 			if enableCRSMetrics {
 				d.Spec.Template.Spec.Containers[i].Args = append(container.Args, flagCRSConfigFile)
 			}
+			additionalAllowList := f.config.ClusterMonitoringConfiguration.KubeStateMetricsConfig.AdditionalLabelsAllowList
+			if additionalAllowList != nil && *additionalAllowList != "" {
+				allowListValidator := ksmpkg.LabelsAllowList{}
+				err = allowListValidator.Set(*additionalAllowList)
+				if err != nil {
+					return nil, fmt.Errorf("error parsing allowlist: %v", err)
+				}
+				for i = range container.Args {
+					if strings.HasPrefix(container.Args[i], "--metric-labels-allowlist=") {
+						container.Args[i] += "," + *additionalAllowList
+					}
+				}
+			}
 		}
 	}
 

pkg/manifests/types.go

@@ -175,6 +175,9 @@ type KubeStateMetricsConfig struct {
 	Tolerations []v1.Toleration `json:"tolerations,omitempty"`
 	// Defines a pod's topology spread constraints.
 	TopologySpreadConstraints []v1.TopologySpreadConstraint `json:"topologySpreadConstraints,omitempty"`
+	// Defines any additional resource-based label-metrics' allow listing in addition to the default one.
+	// Refer: https://pkg.go.dev/k8s.io/kube-state-metrics/[email protected]/pkg/options#LabelsAllowList
+	AdditionalLabelsAllowList *string `json:"additionalLabelsAllowList,omitempty"`
 }
 
 // The `PrometheusK8sConfig` resource defines settings for the Prometheus