feat: add new CoreDNSUpdateStrategy API

nutanix-cloud-native · Oct 31, 2024 · 5dc9fb6 · 5dc9fb6
1 parent 07c7ebe
commit 5dc9fb6
Show file tree

Hide file tree

Showing 10 changed files with 180 additions and 26 deletions.
diff --git a/api/v1alpha1/clusterconfig_types.go b/api/v1alpha1/clusterconfig_types.go
@@ -12,6 +12,11 @@ import (
 	"github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/common/pkg/capi/clustertopology/variables"
 )
 
+const (
+	CoreDNSUpdateStrategyAutomatic CoreDNSUpdateStrategy = "Automatic"
+	CoreDNSUpdateStrategyManual    CoreDNSUpdateStrategy = "Manual"
+)
+
 var (
 	DefaultDockerCertSANs = []string{
 		"localhost",
@@ -320,12 +325,20 @@ type DNS struct {
 	CoreDNS *CoreDNS `json:"coreDNS,omitempty"`
 }
 
+// +kubebuilder:validation:Optional
+// +kubebuilder:validation:Enum=Manual;Automatic
+type CoreDNSUpdateStrategy string
+
 type CoreDNS struct {
 	// Image required for overriding Kubernetes DNS image details.
-	// If the image version is not specified,
-	// the default version based on the cluster's Kubernetes version will be used.
 	// +kubebuilder:validation:Optional
 	Image *Image `json:"image,omitempty"`
+
+	// UpdateStrategy defines the strategy for how the CoreDNS version will be updated.
+	// If not specified, the default value is Automatic,
+	// which sets the CoreDNS version based on the cluster's Kubernetes version.
+	// +kubebuilder:default=Automatic
+	UpdateStrategy *CoreDNSUpdateStrategy `json:"updateStrategy,omitempty"`
 }
 
 //nolint:gochecknoinits // Idiomatic to use init functions to register APIs with scheme.

diff --git a/api/v1alpha1/crds/caren.nutanix.com_awsclusterconfigs.yaml b/api/v1alpha1/crds/caren.nutanix.com_awsclusterconfigs.yaml
@@ -379,10 +379,7 @@ spec:
                       description: CoreDNS defines the CoreDNS configuration for the cluster.
                       properties:
                         image:
-                          description: |-
-                            Image required for overriding Kubernetes DNS image details.
-                            If the image version is not specified,
-                            the default version based on the cluster's Kubernetes version will be used.
+                          description: Image required for overriding Kubernetes DNS image details.
                           properties:
                             repository:
                               description: Repository is used to override the image repository to pull from.
@@ -393,6 +390,16 @@ spec:
                               pattern: ^[\w][\w.-]{0,127}$
                               type: string
                           type: object
+                        updateStrategy:
+                          default: Automatic
+                          description: |-
+                            UpdateStrategy defines the strategy for how the CoreDNS version will be updated.
+                            If not specified, the default value is Automatic,
+                            which sets the CoreDNS version based on the cluster's Kubernetes version.
+                          enum:
+                            - Manual
+                            - Automatic
+                          type: string
                       type: object
                   type: object
                 encryptionAtRest:

diff --git a/api/v1alpha1/crds/caren.nutanix.com_dockerclusterconfigs.yaml b/api/v1alpha1/crds/caren.nutanix.com_dockerclusterconfigs.yaml
@@ -296,10 +296,7 @@ spec:
                       description: CoreDNS defines the CoreDNS configuration for the cluster.
                       properties:
                         image:
-                          description: |-
-                            Image required for overriding Kubernetes DNS image details.
-                            If the image version is not specified,
-                            the default version based on the cluster's Kubernetes version will be used.
+                          description: Image required for overriding Kubernetes DNS image details.
                           properties:
                             repository:
                               description: Repository is used to override the image repository to pull from.
@@ -310,6 +307,16 @@ spec:
                               pattern: ^[\w][\w.-]{0,127}$
                               type: string
                           type: object
+                        updateStrategy:
+                          default: Automatic
+                          description: |-
+                            UpdateStrategy defines the strategy for how the CoreDNS version will be updated.
+                            If not specified, the default value is Automatic,
+                            which sets the CoreDNS version based on the cluster's Kubernetes version.
+                          enum:
+                            - Manual
+                            - Automatic
+                          type: string
                       type: object
                   type: object
                 docker:

diff --git a/api/v1alpha1/crds/caren.nutanix.com_genericclusterconfigs.yaml b/api/v1alpha1/crds/caren.nutanix.com_genericclusterconfigs.yaml
@@ -58,10 +58,8 @@ spec:
                       cluster.
                     properties:
                       image:
-                        description: |-
-                          Image required for overriding Kubernetes DNS image details.
-                          If the image version is not specified,
-                          the default version based on the cluster's Kubernetes version will be used.
+                        description: Image required for overriding Kubernetes DNS
+                          image details.
                         properties:
                           repository:
                             description: Repository is used to override the image
@@ -74,6 +72,16 @@ spec:
                             pattern: ^[\w][\w.-]{0,127}$
                             type: string
                         type: object
+                      updateStrategy:
+                        default: Automatic
+                        description: |-
+                          UpdateStrategy defines the strategy for how the CoreDNS version will be updated.
+                          If not specified, the default value is Automatic,
+                          which sets the CoreDNS version based on the cluster's Kubernetes version.
+                        enum:
+                        - Manual
+                        - Automatic
+                        type: string
                     type: object
                 type: object
               encryptionAtRest:

diff --git a/api/v1alpha1/crds/caren.nutanix.com_nutanixclusterconfigs.yaml b/api/v1alpha1/crds/caren.nutanix.com_nutanixclusterconfigs.yaml
@@ -449,10 +449,7 @@ spec:
                       description: CoreDNS defines the CoreDNS configuration for the cluster.
                       properties:
                         image:
-                          description: |-
-                            Image required for overriding Kubernetes DNS image details.
-                            If the image version is not specified,
-                            the default version based on the cluster's Kubernetes version will be used.
+                          description: Image required for overriding Kubernetes DNS image details.
                           properties:
                             repository:
                               description: Repository is used to override the image repository to pull from.
@@ -463,6 +460,16 @@ spec:
                               pattern: ^[\w][\w.-]{0,127}$
                               type: string
                           type: object
+                        updateStrategy:
+                          default: Automatic
+                          description: |-
+                            UpdateStrategy defines the strategy for how the CoreDNS version will be updated.
+                            If not specified, the default value is Automatic,
+                            which sets the CoreDNS version based on the cluster's Kubernetes version.
+                          enum:
+                            - Manual
+                            - Automatic
+                          type: string
                       type: object
                   type: object
                 encryptionAtRest:

diff --git a/api/v1alpha1/zz_generated.deepcopy.go b/api/v1alpha1/zz_generated.deepcopy.go
diff --git a/docs/content/customization/generic/dns.md b/docs/content/customization/generic/dns.md
@@ -34,6 +34,7 @@ spec:
               image:
                 repository: my-registry.io/my-org/my-repo
                 tag: "v1.11.3_custom.0"
+              updateStrategy: Manual
 ```
 
 Applying this configuration will result in the following value being set:
@@ -48,3 +49,49 @@ Applying this configuration will result in the following value being set:
             imageRepository: "my-registry.io/my-org/my-repo"
             imageTag: "v1.11.3_custom.0"
     ```
+
+The CoreDNS version can also be updated automatically. To do this, set the `updateStrategy` to `Automatic`:
+
+```yaml
+apiVersion: cluster.x-k8s.io/v1beta1
+kind: Cluster
+metadata:
+  name: <NAME>
+spec:
+  topology:
+    variables:
+      - name: clusterConfig
+        value:
+          dns:
+            coreDNS:
+              updateStrategy: Automatic
+```
+
+Alternatively since the default value is `Automatic`, the following configuration is equivalent:
+
+```yaml
+apiVersion: cluster.x-k8s.io/v1beta1
+kind: Cluster
+metadata:
+  name: <NAME>
+spec:
+  topology:
+    variables:
+      - name: clusterConfig
+        value:
+          dns:
+            coreDNS: {}
+```
+
+Applying this configuration will result in the following value being set,
+with the version of the CoreDNS image being set based on the cluster's Kubernetes version:
+
+- `KubeadmControlPlaneTemplate`:
+
+  - ```yaml
+    spec:
+      kubeadmConfigSpec:
+        clusterConfiguration:
+          dns:
+            imageTag: "v1.11.3"
+    ```
diff --git a/pkg/handlers/generic/mutation/coredns/inject.go b/pkg/handlers/generic/mutation/coredns/inject.go
@@ -9,6 +9,7 @@ import (
 
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/utils/ptr"
 	bootstrapv1 "sigs.k8s.io/cluster-api/bootstrap/kubeadm/api/v1beta1"
 	controlplanev1 "sigs.k8s.io/cluster-api/controlplane/kubeadm/api/v1beta1"
 	runtimehooksv1 "sigs.k8s.io/cluster-api/exp/runtime/hooks/api/v1alpha1"
@@ -71,10 +72,11 @@ func (h *coreDNSPatchHandler) Mutate(
 		h.variableFieldPath...,
 	)
 	if err != nil {
-		if !variables.IsNotFoundError(err) {
-			return err
+		if variables.IsNotFoundError(err) {
+			log.V(5).Info("coreDNS variable not defined")
+			return nil
 		}
-		log.V(5).Info("coreDNS variable not defined")
+		return err
 	}
 
 	log = log.WithValues(
@@ -101,7 +103,7 @@ func (h *coreDNSPatchHandler) Mutate(
 			log.WithValues(
 				"patchedObjectKind", obj.GetObjectKind().GroupVersionKind().String(),
 				"patchedObjectName", ctrlclient.ObjectKeyFromObject(obj),
-			).Info("setting CoreDNS version")
+			).Info("setting CoreDNS version if needed")
 
 			if obj.Spec.Template.Spec.KubeadmConfigSpec.ClusterConfiguration == nil {
 				obj.Spec.Template.Spec.KubeadmConfigSpec.ClusterConfiguration = &bootstrapv1.ClusterConfiguration{}
@@ -119,9 +121,14 @@ func (h *coreDNSPatchHandler) Mutate(
 				}
 			}
 
-			// If the CoreDNS image tag is still not set, set the image tag to the default CoreDNS version based on the
+			// If the updateStrategy is set Automatic, set the image tag to the default CoreDNS version based on the
 			// Kubernetes version.
-			if dns.ImageTag == "" {
+			// Default the strategy to Automatic if var is not nil.
+			strategy := ptr.Deref(
+				coreDNSVar.UpdateStrategy,
+				v1alpha1.CoreDNSUpdateStrategyAutomatic,
+			)
+			if strategy == v1alpha1.CoreDNSUpdateStrategyAutomatic {
 				defaultCoreDNSVersion, found := corednsversions.GetCoreDNSVersion(
 					cluster.Spec.Topology.Version,
 				)

diff --git a/pkg/handlers/generic/mutation/coredns/inject_test.go b/pkg/handlers/generic/mutation/coredns/inject_test.go
@@ -13,6 +13,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
+	"k8s.io/utils/ptr"
 	clusterv1 "sigs.k8s.io/cluster-api/api/v1beta1"
 	runtimehooksv1 "sigs.k8s.io/cluster-api/exp/runtime/hooks/api/v1alpha1"
 
@@ -46,7 +47,34 @@ var _ = Describe("Generate CoreDNS patches", func() {
 	testDefs := []testObj{
 		{
 			patchTest: capitest.PatchTestDef{
-				Name:        "unset variable",
+				Name: "unset variable",
+			},
+			cluster: clusterv1.Cluster{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "test-cluster",
+					Namespace: request.Namespace,
+					Labels: map[string]string{
+						clusterv1.ProviderNameLabel: "nutanix",
+					},
+				},
+				Spec: clusterv1.ClusterSpec{
+					Topology: &clusterv1.Topology{
+						Version: "1.30.100",
+					},
+				},
+			},
+		},
+		{
+			patchTest: capitest.PatchTestDef{
+				Name: "variable with defaults",
+				Vars: []runtimehooksv1.Variable{
+					capitest.VariableWithValue(
+						v1alpha1.ClusterConfigVariableName,
+						v1alpha1.CoreDNS{},
+						v1alpha1.DNSVariableName,
+						VariableName,
+					),
+				},
 				RequestItem: request.NewKubeadmControlPlaneTemplateRequestItem(""),
 				ExpectedPatchMatchers: []capitest.JSONPatchMatcher{{
 					Operation: "add",
@@ -85,6 +113,7 @@ var _ = Describe("Generate CoreDNS patches", func() {
 								Repository: "my-registry.io/my-org/my-repo",
 								Tag:        "v1.11.3_custom.0",
 							},
+							UpdateStrategy: ptr.To(v1alpha1.CoreDNSUpdateStrategyManual),
 						},
 						v1alpha1.DNSVariableName,
 						VariableName,
@@ -171,6 +200,7 @@ var _ = Describe("Generate CoreDNS patches", func() {
 							Image: &v1alpha1.Image{
 								Tag: "v1.11.3_custom.0",
 							},
+							UpdateStrategy: ptr.To(v1alpha1.CoreDNSUpdateStrategyManual),
 						},
 						v1alpha1.DNSVariableName,
 						VariableName,
@@ -205,7 +235,15 @@ var _ = Describe("Generate CoreDNS patches", func() {
 		},
 		{
 			patchTest: capitest.PatchTestDef{
-				Name:            "error if cannot find default CoreDNS version",
+				Name: "error if cannot find default CoreDNS version",
+				Vars: []runtimehooksv1.Variable{
+					capitest.VariableWithValue(
+						v1alpha1.ClusterConfigVariableName,
+						v1alpha1.CoreDNS{},
+						v1alpha1.DNSVariableName,
+						VariableName,
+					),
+				},
 				RequestItem:     request.NewKubeadmControlPlaneTemplateRequestItem(""),
 				ExpectedFailure: true,
 			},
@@ -235,6 +273,7 @@ var _ = Describe("Generate CoreDNS patches", func() {
 								Repository: "my-registry.io/my-org/my-repo",
 								Tag:        "v1.11.3_custom.0",
 							},
+							UpdateStrategy: ptr.To(v1alpha1.CoreDNSUpdateStrategyManual),
 						},
 						v1alpha1.DNSVariableName,
 						VariableName,

diff --git a/pkg/handlers/generic/mutation/coredns/variables_test.go b/pkg/handlers/generic/mutation/coredns/variables_test.go
@@ -15,6 +15,10 @@ import (
 	nutanixclusterconfig "github.com/nutanix-cloud-native/cluster-api-runtime-extensions-nutanix/pkg/handlers/nutanix/clusterconfig"
 )
 
+const (
+	invalidUpdateStrategy = v1alpha1.CoreDNSUpdateStrategy("this:is:not:a:valid:update:strategy")
+)
+
 var testDefs = []capitest.VariableTestDef{{
 	Name: "unset",
 	Vals: v1alpha1.GenericClusterConfigSpec{
@@ -78,6 +82,16 @@ var testDefs = []capitest.VariableTestDef{{
 		},
 	},
 	ExpectError: true,
+}, {
+	Name: "set an invalid updateStrategy",
+	Vals: v1alpha1.GenericClusterConfigSpec{
+		DNS: &v1alpha1.DNS{
+			CoreDNS: &v1alpha1.CoreDNS{
+				UpdateStrategy: ptr.To(invalidUpdateStrategy),
+			},
+		},
+	},
+	ExpectError: true,
 }}
 
 func TestVariableValidation_AWS(t *testing.T) {