feat: add --managed-cluster-arn flag to clusteradm join command (#486)

Signed-off-by: Ahmad Ibrahim <[email protected]>

Author: ahmad-ibra

pkg/cmd/join/cmd.go

@@ -83,6 +83,7 @@ func NewCmd(clusteradmFlags *genericclioptionsclusteradm.ClusteradmFlags, stream
 	cmd.Flags().Int32Var(&o.clientCertExpirationSeconds, "client-cert-expiration-seconds", 31536000, "clientCertExpirationSeconds represents the seconds of a client certificate to expire.")
 	cmd.Flags().StringVar(&o.registrationAuth, "registration-auth", "", "The type of authentication to use for registering and authenticating with hub")
 	cmd.Flags().StringVar(&o.hubClusterArn, "hub-cluster-arn", "", "The arn of the hub cluster(i.e. EKS cluster) to which managed-cluster will join")
+	cmd.Flags().StringVar(&o.managedClusterArn, "managed-cluster-arn", "", "The arn of the managed cluster(i.e. EKS cluster) which will be joining the hub")
 	cmd.Flags().StringArrayVar(&o.klusterletAnnotations, "klusterlet-annotation", []string{}, fmt.Sprintf("Annotations to set on the ManagedCluster, in key=value format. Note: each key will be automatically prefixed with '%s/', if not set.", operatorv1.ClusterAnnotationsKeyPrefix))
 	return cmd
 }

pkg/cmd/join/exec.go

@@ -156,17 +156,15 @@ func (o *Options) complete(cmd *cobra.Command, args []string) (err error) {
 
 	// set registration auth type
 	if o.registrationAuth == AwsIrsaAuthentication {
-		rawConfig, err := o.ClusteradmFlags.KubectlFactory.ToRawKubeConfigLoader().RawConfig()
+		managedClusterArn, err := getManagedClusterArn(o)
 		if err != nil {
-			klog.Errorf("unable to load managedcluster kubeconfig: %v", err)
 			return err
 		}
-
 		o.klusterletChartConfig.Klusterlet.RegistrationConfiguration.RegistrationDriver = operatorv1.RegistrationDriver{
 			AuthType: o.registrationAuth,
 			AwsIrsa: &operatorv1.AwsIrsa{
 				HubClusterArn:     o.hubClusterArn,
-				ManagedClusterArn: rawConfig.Contexts[rawConfig.CurrentContext].Cluster,
+				ManagedClusterArn: managedClusterArn,
 			},
 		}
 	}
@@ -774,3 +772,21 @@ func (o *Options) setKlusterletRegistrationAnnotations() {
 		o.klusterletChartConfig.Klusterlet.RegistrationConfiguration.ClusterAnnotations[k] = v
 	}
 }
+
+func getManagedClusterArn(o *Options) (string, error) {
+	if o.managedClusterArn != "" {
+		return o.managedClusterArn, nil
+	}
+
+	rawConfig, err := o.ClusteradmFlags.KubectlFactory.ToRawKubeConfigLoader().RawConfig()
+	if err != nil {
+		klog.Errorf("unable to load managedcluster kubeconfig: %v", err)
+		return "", err
+	}
+	managedClusterArn := rawConfig.Contexts[rawConfig.CurrentContext].Cluster
+	if managedClusterArn == "" {
+		klog.Errorf("managedClusterArn has empty value in kubeconfig")
+		return "", fmt.Errorf("unable to retrieve managedClusterArn from kubeconfig")
+	}
+	return managedClusterArn, nil
+}

pkg/cmd/join/options.go

@@ -93,6 +93,9 @@ type Options struct {
 	// The arn of hub cluster(i.e. EKS) to which managed-cluster will join
 	hubClusterArn string
 
+	// The arn of managed cluster(i.e. EKS) which will be joining the hub
+	managedClusterArn string
+
 	// Annotations for registration controller to set on the ManagedCluster
 	klusterletAnnotations []string
 }