Use mc name as finalizer for kubelet config

The uid was being used as the entry for the finalizer list
but everytime an update happens it generates a new uid, which
is why we were ending up with multiple uids in the finalizers
list. So use the mc name for the list of finalizer instead as
the mc name stays the same for each kubelet config.

Signed-off-by: Urvashi Mohnani <umohnani@redhat.com>

pkg/controller/kubelet-config/kubelet_config_controller.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"reflect"
+	"strings"
 	"time"
 
 	"github.com/clarketm/json"
@@ -574,17 +575,24 @@ func (ctrl *Controller) addFinalizerToKubeletConfig(kc *mcfgv1.KubeletConfig, mc
 			return err
 		}
 
-		uid := string(mc.ObjectMeta.GetUID())
-
-		// if the finalizer is already set then skip
+		kcTmp := newcfg.DeepCopy()
+		// We want to use the mc name as the finalizer instead of the uid because
+		// every time a resync happens, a new uid is generated. This is why the list
+		// of finalizers had multiple entries. So check if the list of finalizers consists
+		// of uids, if it does then clear the list of finalizers and we will add the mc
+		// name to it, ensuring we don't have duplicate or multiple finalizers.
 		for _, finalizerName := range newcfg.Finalizers {
-			if finalizerName == mc.Name || finalizerName == uid {
-				return nil
+			if !strings.Contains(finalizerName, "kubelet") {
+				kcTmp.ObjectMeta.SetFinalizers([]string{})
 			}
 		}
-
-		kcTmp := newcfg.DeepCopy()
-		kcTmp.ObjectMeta.Finalizers = append(kcTmp.ObjectMeta.Finalizers, uid)
+		// Only append the mc name if it is not already in the list of finalizers.
+		// When we update an existing kubeletconfig, the generation number increases causing
+		// a resync to happen. When this happens, the mc name is the same, so we don't
+		// want to add duplicate entries to the list of finalizers.
+		if !ctrlcommon.InSlice(mc.Name, kcTmp.ObjectMeta.Finalizers) {
+			kcTmp.ObjectMeta.Finalizers = append(kcTmp.ObjectMeta.Finalizers, mc.Name)
+		}
 
 		modJSON, err := json.Marshal(kcTmp)
 		if err != nil {