Pass around comma separate strings rather than lists

As per https://github.com/kubernetes/autoscaler/pull/6788/files#r1624695422

vertical-pod-autoscaler/pkg/admission-controller/config.go

@@ -90,7 +90,7 @@ func configTLS(cfg certsConfig, minTlsVersion, ciphers string, stop <-chan struc
 
 // register this webhook admission controller with the kube-apiserver
 // by creating MutatingWebhookConfiguration.
-func selfRegistration(clientset kubernetes.Interface, caCert []byte, namespace, serviceName, url string, registerByURL bool, timeoutSeconds int32, selectedNamespaces []string, ignoredNamespaces []string) {
+func selfRegistration(clientset kubernetes.Interface, caCert []byte, namespace, serviceName, url string, registerByURL bool, timeoutSeconds int32, selectedNamespaces string, ignoredNamespaces string) {
 	time.Sleep(10 * time.Second)
 	client := clientset.AdmissionregistrationV1().MutatingWebhookConfigurations()
 	_, err := client.Get(context.TODO(), webhookConfigName, metav1.GetOptions{})
@@ -112,14 +112,17 @@ func selfRegistration(clientset kubernetes.Interface, caCert []byte, namespace,
 	failurePolicy := admissionregistration.Ignore
 	RegisterClientConfig.CABundle = caCert
 
+	selectedNamespacesList := strings.Split(selectedNamespaces, ",")
+	ignoredNamespacesList := strings.Split(ignoredNamespaces, ",")
+
 	var namespaceSelector metav1.LabelSelector
 	if len(ignoredNamespaces) > 0 {
 		namespaceSelector = metav1.LabelSelector{
 			MatchExpressions: []metav1.LabelSelectorRequirement{
 				{
 					Key:      "kubernetes.io/metadata.name",
 					Operator: metav1.LabelSelectorOpNotIn,
-					Values:   ignoredNamespaces,
+					Values:   ignoredNamespacesList,
 				},
 			},
 		}
@@ -129,7 +132,7 @@ func selfRegistration(clientset kubernetes.Interface, caCert []byte, namespace,
 				{
 					Key:      "kubernetes.io/metadata.name",
 					Operator: metav1.LabelSelectorOpIn,
-					Values:   selectedNamespaces,
+					Values:   selectedNamespacesList,
 				},
 			},
 		}

vertical-pod-autoscaler/pkg/admission-controller/config_test.go

@@ -18,6 +18,7 @@ package main
 
 import (
 	"context"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -35,8 +36,8 @@ func TestSelfRegistrationBase(t *testing.T) {
 	url := "http://example.com/"
 	registerByURL := true
 	timeoutSeconds := int32(32)
-	selectedNamespaces := []string{}
-	ignoredNamespaces := []string{}
+	selectedNamespaces := ""
+	ignoredNamespaces := ""
 
 	selfRegistration(testClientSet, caCert, namespace, serviceName, url, registerByURL, timeoutSeconds, selectedNamespaces, ignoredNamespaces)
 
@@ -77,8 +78,8 @@ func TestSelfRegistrationWithURL(t *testing.T) {
 	url := "http://example.com/"
 	registerByURL := true
 	timeoutSeconds := int32(32)
-	selectedNamespaces := []string{}
-	ignoredNamespaces := []string{}
+	selectedNamespaces := ""
+	ignoredNamespaces := ""
 
 	selfRegistration(testClientSet, caCert, namespace, serviceName, url, registerByURL, timeoutSeconds, selectedNamespaces, ignoredNamespaces)
 
@@ -104,8 +105,8 @@ func TestSelfRegistrationWithOutURL(t *testing.T) {
 	url := "http://example.com/"
 	registerByURL := false
 	timeoutSeconds := int32(32)
-	selectedNamespaces := []string{}
-	ignoredNamespaces := []string{}
+	selectedNamespaces := ""
+	ignoredNamespaces := ""
 
 	selfRegistration(testClientSet, caCert, namespace, serviceName, url, registerByURL, timeoutSeconds, selectedNamespaces, ignoredNamespaces)
 
@@ -118,8 +119,8 @@ func TestSelfRegistrationWithOutURL(t *testing.T) {
 	webhook := webhookConfig.Webhooks[0]
 
 	assert.NotNil(t, webhook.ClientConfig.Service, "expected service reference to be nil")
-	assert.Equal(t, webhook.ClientConfig.Service.Name, serviceName, "expected service name to be equal")
-	assert.Equal(t, webhook.ClientConfig.Service.Namespace, namespace, "expected service namespace to be equal")
+	assert.Equal(t, serviceName, webhook.ClientConfig.Service.Name, "expected service name to be equal")
+	assert.Equal(t, namespace, webhook.ClientConfig.Service.Namespace, "expected service namespace to be equal")
 
 	assert.Nil(t, webhook.ClientConfig.URL, "expected URL to be set")
 }
@@ -133,8 +134,8 @@ func TestSelfRegistrationWithIgnoredNamespaces(t *testing.T) {
 	url := "http://example.com/"
 	registerByURL := false
 	timeoutSeconds := int32(32)
-	selectedNamespaces := []string{}
-	ignoredNamespaces := []string{"test"}
+	selectedNamespaces := ""
+	ignoredNamespaces := "test"
 
 	selfRegistration(testClientSet, caCert, namespace, serviceName, url, registerByURL, timeoutSeconds, selectedNamespaces, ignoredNamespaces)
 
@@ -150,8 +151,8 @@ func TestSelfRegistrationWithIgnoredNamespaces(t *testing.T) {
 	assert.Len(t, webhook.NamespaceSelector.MatchExpressions, 1, "expected one match expression")
 
 	matchExpression := webhook.NamespaceSelector.MatchExpressions[0]
-	assert.Equal(t, matchExpression.Operator, metav1.LabelSelectorOpNotIn, "expected namespace operator to be OpNotIn")
-	assert.Equal(t, matchExpression.Values, ignoredNamespaces, "expected namespace selector match expression to be equal")
+	assert.Equal(t, metav1.LabelSelectorOpNotIn, matchExpression.Operator, "expected namespace operator to be OpNotIn")
+	assert.Equal(t, strings.Split(ignoredNamespaces, ","), matchExpression.Values, "expected namespace selector match expression to be equal")
 }
 
 func TestSelfRegistrationWithSelectedNamespaces(t *testing.T) {
@@ -163,8 +164,8 @@ func TestSelfRegistrationWithSelectedNamespaces(t *testing.T) {
 	url := "http://example.com/"
 	registerByURL := false
 	timeoutSeconds := int32(32)
-	selectedNamespaces := []string{"test"}
-	ignoredNamespaces := []string{}
+	selectedNamespaces := "test,namespaces"
+	ignoredNamespaces := ""
 
 	selfRegistration(testClientSet, caCert, namespace, serviceName, url, registerByURL, timeoutSeconds, selectedNamespaces, ignoredNamespaces)
 
@@ -180,6 +181,6 @@ func TestSelfRegistrationWithSelectedNamespaces(t *testing.T) {
 	assert.Len(t, webhook.NamespaceSelector.MatchExpressions, 1, "expected one match expression")
 
 	matchExpression := webhook.NamespaceSelector.MatchExpressions[0]
-	assert.Equal(t, matchExpression.Operator, metav1.LabelSelectorOpIn, "expected namespace operator to be OpIn")
-	assert.Equal(t, matchExpression.Values, selectedNamespaces, "expected namespace selector match expression to be equal")
+	assert.Equal(t, metav1.LabelSelectorOpIn, matchExpression.Operator, "expected namespace operator to be OpIn")
+	assert.Equal(t, strings.Split(selectedNamespaces, ","), matchExpression.Values, "expected namespace selector match expression to be equal")
 }

vertical-pod-autoscaler/pkg/admission-controller/main.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"net/http"
 	"os"
-	"strings"
 	"time"
 
 	apiv1 "k8s.io/api/core/v1"
@@ -142,11 +141,9 @@ func main() {
 		TLSConfig: configTLS(*certsConfiguration, *minTlsVersion, *ciphers, stopCh),
 	}
 	url := fmt.Sprintf("%v:%v", *webhookAddress, *webhookPort)
-	selectedNamespaces := strings.Split(*vpaObjectNamespace, ",")
-	ignoredNamespaces := strings.Split(*ignoredVpaObjectNamespaces, ",")
 	go func() {
 		if *registerWebhook {
-			selfRegistration(kubeClient, readFile(*certsConfiguration.clientCaFile), namespace, *serviceName, url, *registerByURL, int32(*webhookTimeout), selectedNamespaces, ignoredNamespaces)
+			selfRegistration(kubeClient, readFile(*certsConfiguration.clientCaFile), namespace, *serviceName, url, *registerByURL, int32(*webhookTimeout), *vpaObjectNamespace, *ignoredVpaObjectNamespaces)
 		}
 		// Start status updates after the webhook is initialized.
 		statusUpdater.Run(stopCh)

vertical-pod-autoscaler/pkg/recommender/input/cluster_feeder.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"fmt"
 	"slices"
+	"strings"
 	"time"
 
 	apiv1 "k8s.io/api/core/v1"
@@ -88,7 +89,7 @@ type ClusterStateFeederFactory struct {
 	MemorySaveMode      bool
 	ControllerFetcher   controllerfetcher.ControllerFetcher
 	RecommenderName     string
-	IgnoredNamespaces   []string
+	IgnoredNamespaces   string
 }
 
 // Make creates new ClusterStateFeeder with internal data providers, based on kube client.
@@ -105,7 +106,7 @@ func (m ClusterStateFeederFactory) Make() *clusterStateFeeder {
 		memorySaveMode:      m.MemorySaveMode,
 		controllerFetcher:   m.ControllerFetcher,
 		recommenderName:     m.RecommenderName,
-		ignoredNamespaces:   m.IgnoredNamespaces,
+		ignoredNamespaces:   strings.Split(m.IgnoredNamespaces, ","),
 	}
 }
 

vertical-pod-autoscaler/pkg/recommender/main.go

@@ -19,7 +19,6 @@ package main
 import (
 	"context"
 	"flag"
-	"strings"
 	"time"
 
 	resourceclient "k8s.io/metrics/pkg/client/clientset/versioned/typed/metrics/v1beta1"
@@ -156,8 +155,6 @@ func main() {
 		source = input_metrics.NewPodMetricsesSource(resourceclient.NewForConfigOrDie(config))
 	}
 
-	ignoredNamespaces := strings.Split(*ignoredVpaObjectNamespaces, ",")
-
 	clusterStateFeeder := input.ClusterStateFeederFactory{
 		PodLister:           podLister,
 		OOMObserver:         oomObserver,
@@ -170,7 +167,7 @@ func main() {
 		MemorySaveMode:      *memorySaver,
 		ControllerFetcher:   controllerFetcher,
 		RecommenderName:     *recommenderName,
-		IgnoredNamespaces:   ignoredNamespaces,
+		IgnoredNamespaces:   *ignoredVpaObjectNamespaces,
 	}.Make()
 	controllerFetcher.Start(context.Background(), scaleCacheLoopPeriod)
 

vertical-pod-autoscaler/pkg/updater/logic/updater.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"fmt"
 	"slices"
+	"strings"
 	"time"
 
 	"golang.org/x/time/rate"
@@ -86,7 +87,7 @@ func NewUpdater(
 	controllerFetcher controllerfetcher.ControllerFetcher,
 	priorityProcessor priority.PriorityProcessor,
 	namespace string,
-	ignoredNamespaces []string,
+	ignoredNamespaces string,
 ) (Updater, error) {
 	evictionRateLimiter := getRateLimiter(evictionRateLimit, evictionRateBurst)
 	factory, err := eviction.NewPodsEvictionRestrictionFactory(kubeClient, minReplicasForEvicition, evictionToleranceFraction)
@@ -110,7 +111,7 @@ func NewUpdater(
 			status.AdmissionControllerStatusName,
 			statusNamespace,
 		),
-		ignoredNamespaces: ignoredNamespaces,
+		ignoredNamespaces: strings.Split(ignoredNamespaces, ","),
 	}, nil
 }
 

vertical-pod-autoscaler/pkg/updater/main.go

@@ -20,7 +20,6 @@ import (
 	"context"
 	"flag"
 	"os"
-	"strings"
 	"time"
 
 	apiv1 "k8s.io/api/core/v1"
@@ -108,8 +107,6 @@ func main() {
 		admissionControllerStatusNamespace = namespace
 	}
 
-	ignoredNamespaces := strings.Split(*ignoredVpaObjectNamespaces, ",")
-
 	// TODO: use SharedInformerFactory in updater
 	updater, err := updater.NewUpdater(
 		kubeClient,
@@ -126,7 +123,7 @@ func main() {
 		controllerFetcher,
 		priority.NewProcessor(),
 		*vpaObjectNamespace,
-		ignoredNamespaces,
+		*ignoredVpaObjectNamespaces,
 	)
 	if err != nil {
 		klog.Fatalf("Failed to create updater: %v", err)