refactor: keep only common types in Generic config specs (#1297)

**What problem does this PR solve?**:
After EKS types were introduced, the fields in
`GenericClusterConfigSpec` and `GenericNodeSpec` are no longer all
"generic" because some do not apply to EKS clusters, as it does not use
kubeadm to create the cluster.

This PR attempts to address this by only keeping the fields that can be
set for both EKS and all other infra types in `GenericClusterConfigSpec`
and moves the rest of the fields to `KubeadmClusterConfigSpec`, and
similarly for `GenericNodeSpec`.

Because the structs are included `inline` in the individual Cluster
types this does not change the external yaml API, only how they are
referenced in Go (notice how the CRDs for
<aws|docker|nutanix>clusterconfigs did not change).

**Which issue(s) this PR fixes**:
Fixes #

**How Has This Been Tested?**:
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Provide output from the tests and any manual steps needed to replicate
the tests.
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Unit tests.

**Special notes for your reviewer**:
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If we agree with this approach I will have separate refactor PRs to
reorganize the handlers and the public docs.

Author: dkoshkin

api/v1alpha1/clusterconfig_types.go

@@ -32,6 +32,8 @@ var (
 	awsClusterConfigCRDDefinition []byte
 	//go:embed crds/caren.nutanix.com_nutanixclusterconfigs.yaml
 	nutanixClusterConfigCRDDefinition []byte
+	//go:embed crds/caren.nutanix.com_kubeadmclusterconfigs.yaml
+	kubeadmClusterConfigCRDDefinition []byte
 	//go:embed crds/caren.nutanix.com_genericclusterconfigs.yaml
 	genericClusterConfigCRDDefinition []byte
 	//go:embed crds/caren.nutanix.com_eksclusterconfigs.yaml
@@ -46,6 +48,9 @@ var (
 	nutanixClusterConfigVariableSchema = variables.MustSchemaFromCRDYAML(
 		nutanixClusterConfigCRDDefinition,
 	)
+	kubeadmClusterConfigVariableSchema = variables.MustSchemaFromCRDYAML(
+		kubeadmClusterConfigCRDDefinition,
+	)
 	genericClusterConfigVariableSchema = variables.MustSchemaFromCRDYAML(
 		genericClusterConfigCRDDefinition,
 	)
@@ -75,6 +80,7 @@ type AWSClusterConfigSpec struct {
 	// +kubebuilder:validation:Optional
 	AWS *AWSSpec `json:"aws,omitempty"`
 
+	KubeadmClusterConfigSpec `json:",inline"`
 	GenericClusterConfigSpec `json:",inline"`
 
 	// +kubebuilder:validation:Optional
@@ -112,6 +118,7 @@ type DockerClusterConfigSpec struct {
 	// +kubebuilder:validation:Optional
 	Docker *DockerSpec `json:"docker,omitempty"`
 
+	KubeadmClusterConfigSpec `json:",inline"`
 	GenericClusterConfigSpec `json:",inline"`
 
 	// +kubebuilder:validation:Optional
@@ -154,6 +161,7 @@ type NutanixClusterConfigSpec struct {
 	// +kubebuilder:validation:Optional
 	Nutanix *NutanixSpec `json:"nutanix,omitempty"`
 
+	KubeadmClusterConfigSpec `json:",inline"`
 	GenericClusterConfigSpec `json:",inline"`
 
 	// +kubebuilder:validation:Optional
@@ -177,29 +185,21 @@ type NutanixClusterConfigSpec struct {
 
 // +kubebuilder:object:root=true
 
-// GenericClusterConfig is the Schema for the genericclusterconfigs API.
-type GenericClusterConfig struct {
+// KubeadmClusterConfig is the Schema for the kubeadmconfigs API.
+type KubeadmClusterConfig struct {
 	metav1.TypeMeta   `json:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty"`
 
 	// +kubebuilder:validation:Optional
-	Spec *GenericClusterConfigSpec `json:"spec,omitempty"`
-
-	// Extra Subject Alternative Names for the API Server signing cert.
-	// +kubebuilder:validation:UniqueItems=true
-	// +kubebuilder:validation:items:Pattern=`^[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*$`
-	// +kubebuilder:validation:Optional
-	// +kubebuilder:validation:MaxItems=100
-	// +kubebuilder:validation:items:MaxLength=253
-	ExtraAPIServerCertSANs []string `json:"extraAPIServerCertSANs,omitempty"`
+	Spec KubeadmClusterConfigSpec `json:"spec,omitempty"`
 }
 
-func (s GenericClusterConfig) VariableSchema() clusterv1.VariableSchema { //nolint:gocritic,lll // Passed by value for no potential side-effect.
-	return genericClusterConfigVariableSchema
+func (s KubeadmClusterConfig) VariableSchema() clusterv1.VariableSchema { //nolint:gocritic,lll // Passed by value for no potential side-effect.
+	return kubeadmClusterConfigVariableSchema
 }
 
-// GenericClusterConfigSpec defines the desired state of GenericClusterConfig.
-type GenericClusterConfigSpec struct {
+// KubeadmConfigSpec defines configuration that can be set when using kubeadm to bootstrap the cluster.
+type KubeadmClusterConfigSpec struct {
 	// Sets the Kubernetes image repository used for the KubeadmControlPlane.
 	// +kubebuilder:validation:Optional
 	// +kubebuilder:validation:Pattern=`^((?:[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*|\[(?:[a-fA-F0-9:]+)\])(:[0-9]+)?/)?[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*(/[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*)*$`
@@ -211,28 +211,46 @@ type GenericClusterConfigSpec struct {
 	Etcd *Etcd `json:"etcd,omitempty"`
 
 	// +kubebuilder:validation:Optional
-	Proxy *HTTPProxy `json:"proxy,omitempty"`
+	EncryptionAtRest *EncryptionAtRest `json:"encryptionAtRest,omitempty"`
 
 	// +kubebuilder:validation:Optional
-	// +kubebuilder:validation:MaxItems=32
-	ImageRegistries []ImageRegistry `json:"imageRegistries,omitempty"`
+	DNS *DNS `json:"dns,omitempty"`
 
+	// KubeProxy defines the configuration for kube-proxy.
 	// +kubebuilder:validation:Optional
-	GlobalImageRegistryMirror *GlobalImageRegistryMirror `json:"globalImageRegistryMirror,omitempty"`
+	KubeProxy *KubeProxy `json:"kubeProxy,omitempty"`
+}
+
+// +kubebuilder:object:root=true
+
+// GenericClusterConfig is the Schema for the genericclusterconfigs API.
+type GenericClusterConfig struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata,omitempty"`
 
 	// +kubebuilder:validation:Optional
-	// +kubebuilder:validation:MaxItems=32
-	Users []User `json:"users,omitempty"`
+	Spec *GenericClusterConfigSpec `json:"spec,omitempty"`
+}
 
+func (s GenericClusterConfig) VariableSchema() clusterv1.VariableSchema { //nolint:gocritic,lll // Passed by value for no potential side-effect.
+	return genericClusterConfigVariableSchema
+}
+
+// GenericClusterConfigSpec defines the desired state of GenericClusterConfig.
+type GenericClusterConfigSpec struct {
 	// +kubebuilder:validation:Optional
-	EncryptionAtRest *EncryptionAtRest `json:"encryptionAtRest,omitempty"`
+	Proxy *HTTPProxy `json:"proxy,omitempty"`
 
 	// +kubebuilder:validation:Optional
-	DNS *DNS `json:"dns,omitempty"`
+	// +kubebuilder:validation:MaxItems=32
+	ImageRegistries []ImageRegistry `json:"imageRegistries,omitempty"`
 
-	// KubeProxy defines the configuration for kube-proxy.
 	// +kubebuilder:validation:Optional
-	KubeProxy *KubeProxy `json:"kubeProxy,omitempty"`
+	GlobalImageRegistryMirror *GlobalImageRegistryMirror `json:"globalImageRegistryMirror,omitempty"`
+
+	// +kubebuilder:validation:Optional
+	// +kubebuilder:validation:MaxItems=32
+	Users []User `json:"users,omitempty"`
 
 	// NTP defines the NTP configuration for the cluster.
 	// +kubebuilder:validation:Optional

api/v1alpha1/controlplane_types.go

@@ -26,6 +26,7 @@ type DockerControlPlaneSpec struct {
 
 	GenericControlPlaneSpec `json:",inline"`
 
+	KubeadmNodeSpec `json:",inline"`
 	GenericNodeSpec `json:",inline"`
 }
 
@@ -36,6 +37,7 @@ type NutanixControlPlaneSpec struct {
 
 	GenericControlPlaneSpec `json:",inline"`
 
+	KubeadmNodeSpec `json:",inline"`
 	GenericNodeSpec `json:",inline"`
 }
 
@@ -46,5 +48,6 @@ type AWSControlPlaneSpec struct {
 
 	GenericControlPlaneSpec `json:",inline"`
 
+	KubeadmNodeSpec `json:",inline"`
 	GenericNodeSpec `json:",inline"`
 }

api/v1alpha1/crds/caren.nutanix.com_awsclusterconfigs.yaml

@@ -427,7 +427,7 @@ spec:
                       type: object
                     nodeRegistration:
                       default: {}
-                      description: NodeRegistration holds fields that relate to registering the new control-plane node to the cluster.
+                      description: NodeRegistration holds fields that relate to registering the new node to the cluster.
                       properties:
                         ignorePreflightErrors:
                           default:

api/v1alpha1/crds/caren.nutanix.com_awsworkernodeconfigs.yaml

@@ -121,7 +121,7 @@ spec:
               nodeRegistration:
                 default: {}
                 description: NodeRegistration holds fields that relate to registering
-                  the new control-plane node to the cluster.
+                  the new node to the cluster.
                 properties:
                   ignorePreflightErrors:
                     default:

api/v1alpha1/crds/caren.nutanix.com_dockerclusterconfigs.yaml

@@ -328,7 +328,7 @@ spec:
                       type: object
                     nodeRegistration:
                       default: {}
-                      description: NodeRegistration holds fields that relate to registering the new control-plane node to the cluster.
+                      description: NodeRegistration holds fields that relate to registering the new node to the cluster.
                       properties:
                         ignorePreflightErrors:
                           default:

api/v1alpha1/crds/caren.nutanix.com_dockerworkernodeconfigs.yaml

@@ -73,7 +73,7 @@ spec:
               nodeRegistration:
                 default: {}
                 description: NodeRegistration holds fields that relate to registering
-                  the new control-plane node to the cluster.
+                  the new node to the cluster.
                 properties:
                   ignorePreflightErrors:
                     default:

api/v1alpha1/crds/caren.nutanix.com_genericclusterconfigs.yaml

@@ -29,16 +29,6 @@ spec:
               may reject unrecognized values.
               More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources
             type: string
-          extraAPIServerCertSANs:
-            description: Extra Subject Alternative Names for the API Server signing
-              cert.
-            items:
-              maxLength: 253
-              pattern: ^[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*$
-              type: string
-            maxItems: 100
-            type: array
-            uniqueItems: true
           kind:
             description: |-
               Kind is a string value representing the REST resource this object represents.
@@ -52,76 +42,6 @@ spec:
           spec:
             description: GenericClusterConfigSpec defines the desired state of GenericClusterConfig.
             properties:
-              dns:
-                description: DNS defines the DNS configuration for the cluster.
-                properties:
-                  coreDNS:
-                    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.
-                        properties:
-                          repository:
-                            description: Repository is used to override the image
-                              repository to pull from.
-                            maxLength: 2048
-                            minLength: 1
-                            pattern: ^((?:[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*|\[(?:[a-fA-F0-9:]+)\])(:[0-9]+)?/)?[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*(/[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*)*$
-                            type: string
-                          tag:
-                            description: Tag is used to override the default image
-                              tag.
-                            maxLength: 128
-                            minLength: 1
-                            pattern: ^[\w][\w.-]{0,127}$
-                            type: string
-                        type: object
-                    type: object
-                type: object
-              encryptionAtRest:
-                description: |-
-                  EncryptionAtRest defines the configuration to enable encryption at REST
-                  This configuration is used by API server to encrypt data before storing it in ETCD.
-                  Currently the encryption only enabled for secrets and configmaps.
-                properties:
-                  providers:
-                    default:
-                    - aescbc: {}
-                    description: Encryption providers
-                    items:
-                      properties:
-                        aescbc:
-                          type: object
-                        secretbox:
-                          type: object
-                      type: object
-                    maxItems: 1
-                    type: array
-                type: object
-              etcd:
-                properties:
-                  image:
-                    description: Image required for overriding etcd image details.
-                    properties:
-                      repository:
-                        description: Repository is used to override the image repository
-                          to pull from.
-                        maxLength: 2048
-                        minLength: 1
-                        pattern: ^((?:[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*|\[(?:[a-fA-F0-9:]+)\])(:[0-9]+)?/)?[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*(/[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*)*$
-                        type: string
-                      tag:
-                        description: Tag is used to override the default image tag.
-                        maxLength: 128
-                        minLength: 1
-                        pattern: ^[\w][\w.-]{0,127}$
-                        type: string
-                    type: object
-                type: object
               globalImageRegistryMirror:
                 description: GlobalImageRegistryMirror sets default mirror configuration
                   for all the image registries.
@@ -188,28 +108,6 @@ spec:
                   type: object
                 maxItems: 32
                 type: array
-              kubeProxy:
-                description: KubeProxy defines the configuration for kube-proxy.
-                properties:
-                  mode:
-                    description: |-
-                      Mode specifies the mode for kube-proxy:
-                      - iptables means that kube-proxy is installed in iptables mode.
-                      - nftables means that kube-proxy is installed in nftables mode.
-                    enum:
-                    - iptables
-                    - nftables
-                    type: string
-                    x-kubernetes-validations:
-                    - message: Value cannot be changed after cluster creation
-                      rule: self == oldSelf
-                type: object
-              kubernetesImageRepository:
-                description: Sets the Kubernetes image repository used for the KubeadmControlPlane.
-                maxLength: 2048
-                minLength: 1
-                pattern: ^((?:[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*|\[(?:[a-fA-F0-9:]+)\])(:[0-9]+)?/)?[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*(/[a-z0-9]+((?:[._]|__|[-]+)[a-z0-9]+)*)*$
-                type: string
               ntp:
                 description: NTP defines the NTP configuration for the cluster.
                 properties: