From f1b2729dcb72729a06be8aa3ddc23a86781cf978 Mon Sep 17 00:00:00 2001
From: Nader Ziada <nziada@pivotal.io>
Date: Mon, 9 Mar 2020 13:31:32 -0400
Subject: [PATCH] validation for not having both local and external etcd in kcp

---
 .../v1alpha3/kubeadm_control_plane_webhook.go | 27 +++++++++++++++++++
 .../kubeadm_control_plane_webhook_test.go     | 25 +++++++++++++++--
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go
index ba709020d84e..30497618196c 100644
--- a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go
+++ b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook.go
@@ -82,6 +82,9 @@ func (in *KubeadmControlPlane) ValidateUpdate(old runtime.Object) error {
 	allErrs := in.validateCommon()
 
 	prev := old.(*KubeadmControlPlane)
+
+	allErrs = append(allErrs, in.validateEtcd(prev)...)
+
 	originalJSON, err := json.Marshal(prev)
 	if err != nil {
 		return apierrors.NewInternalError(err)
@@ -229,6 +232,30 @@ func (in *KubeadmControlPlane) validateCommon() (allErrs field.ErrorList) {
 	return allErrs
 }
 
+func (in *KubeadmControlPlane) validateEtcd(prev *KubeadmControlPlane) (allErrs field.ErrorList) {
+	if in.Spec.KubeadmConfigSpec.InitConfiguration.Etcd.External != nil && prev.Spec.KubeadmConfigSpec.InitConfiguration.Etcd.Local != nil {
+		allErrs = append(
+			allErrs,
+			field.Forbidden(
+				field.NewPath("spec", "kubeadmConfigSpec", "initConfiguration", "etcd", "local"),
+				"cannot have both local and external etcd at the same time",
+			),
+		)
+	}
+
+	if in.Spec.KubeadmConfigSpec.InitConfiguration.Etcd.Local != nil && prev.Spec.KubeadmConfigSpec.InitConfiguration.Etcd.External != nil {
+		allErrs = append(
+			allErrs,
+			field.Forbidden(
+				field.NewPath("spec", "kubeadmConfigSpec", "initConfiguration", "etcd", "local"),
+				"cannot have both local and external etcd at the same time",
+			),
+		)
+	}
+
+	return allErrs
+}
+
 // ValidateDelete implements webhook.Validator so a webhook will be registered for the type
 func (in *KubeadmControlPlane) ValidateDelete() error {
 	return nil
diff --git a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go
index 1634936ad9f0..a624601200a3 100644
--- a/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go
+++ b/controlplane/kubeadm/api/v1alpha3/kubeadm_control_plane_webhook_test.go
@@ -21,11 +21,9 @@ import (
 	"time"
 
 	. "github.com/onsi/gomega"
-
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/utils/pointer"
-
 	bootstrapv1 "sigs.k8s.io/cluster-api/bootstrap/kubeadm/api/v1alpha3"
 	kubeadmv1beta1 "sigs.k8s.io/cluster-api/bootstrap/kubeadm/types/v1beta1"
 )
@@ -293,6 +291,23 @@ func TestKubeadmControlPlaneValidateUpdate(t *testing.T) {
 	scaleToEvenExternalEtcdCluster := beforeExternalEtcdCluster.DeepCopy()
 	scaleToEvenExternalEtcdCluster.Spec.Replicas = pointer.Int32Ptr(2)
 
+	beforeInvalidEtcdCluster := before.DeepCopy()
+	beforeInvalidEtcdCluster.Spec.KubeadmConfigSpec.InitConfiguration.ClusterConfiguration.Etcd = kubeadmv1beta1.Etcd{
+		Local: &kubeadmv1beta1.LocalEtcd{
+			ImageMeta: kubeadmv1beta1.ImageMeta{
+				ImageRepository: "image-repository",
+				ImageTag:        "latest",
+			},
+		},
+	}
+
+	afterInvalidEtcdCluster := beforeInvalidEtcdCluster.DeepCopy()
+	afterInvalidEtcdCluster.Spec.KubeadmConfigSpec.InitConfiguration.ClusterConfiguration.Etcd = kubeadmv1beta1.Etcd{
+		External: &kubeadmv1beta1.ExternalEtcd{
+			Endpoints: []string{"127.0.0.1"},
+		},
+	}
+
 	tests := []struct {
 		name      string
 		expectErr bool
@@ -473,6 +488,12 @@ func TestKubeadmControlPlaneValidateUpdate(t *testing.T) {
 			before:    localDataDir,
 			kcp:       modifyLocalDataDir,
 		},
+		{
+			name:      "should fail if both local and external etcd are set",
+			expectErr: true,
+			before:    beforeInvalidEtcdCluster,
+			kcp:       afterInvalidEtcdCluster,
+		},
 	}
 
 	for _, tt := range tests {