feat: kubeconfig generator (#933)

* feat(api): kubeconfig generator

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

* refactor: abstracting enqueue to channel function

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

* fix: avoiding multiple context registration

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

* feat: kubeconfig generator

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

* docs: kubeconfig generator

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

* feat(helm): deployment for kubeconfig generator

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

---------

Signed-off-by: Dario Tranchitella <dario@tranchitella.eu>

Makefile

@@ -131,12 +131,14 @@ webhook: controller-gen yq
 crds: controller-gen yq
 	# kamaji chart
 	$(CONTROLLER_GEN) crd webhook paths="./..." output:stdout | $(YQ) 'select(documentIndex == 0)' > ./charts/kamaji/crds/kamaji.clastix.io_datastores.yaml
-	$(CONTROLLER_GEN) crd webhook paths="./..." output:stdout | $(YQ) 'select(documentIndex == 1)' > ./charts/kamaji/crds/kamaji.clastix.io_tenantcontrolplanes.yaml
+	$(CONTROLLER_GEN) crd webhook paths="./..." output:stdout | $(YQ) 'select(documentIndex == 1)' > ./charts/kamaji/crds/kamaji.clastix.io_kubeconfiggenerators.yaml
+	$(CONTROLLER_GEN) crd webhook paths="./..." output:stdout | $(YQ) 'select(documentIndex == 2)' > ./charts/kamaji/crds/kamaji.clastix.io_tenantcontrolplanes.yaml
 	$(YQ) -i '. *n load("./charts/kamaji/controller-gen/crd-conversion.yaml")' ./charts/kamaji/crds/kamaji.clastix.io_tenantcontrolplanes.yaml
 	# kamaji-crds chart
 	cp ./charts/kamaji/controller-gen/crd-conversion.yaml ./charts/kamaji-crds/hack/crd-conversion.yaml
 	$(YQ) '.spec' ./charts/kamaji/crds/kamaji.clastix.io_datastores.yaml > ./charts/kamaji-crds/hack/kamaji.clastix.io_datastores_spec.yaml
 	$(YQ) '.spec' ./charts/kamaji/crds/kamaji.clastix.io_tenantcontrolplanes.yaml > ./charts/kamaji-crds/hack/kamaji.clastix.io_tenantcontrolplanes_spec.yaml
+	$(YQ) '.spec' ./charts/kamaji/crds/kamaji.clastix.io_kubeconfiggenerators.yaml > ./charts/kamaji-crds/hack/kamaji.clastix.io_kubeconfiggenerators_spec.yaml
 	$(YQ) -i '.conversion.webhook.clientConfig.service.name = "{{ .Values.kamajiService }}"' ./charts/kamaji-crds/hack/kamaji.clastix.io_tenantcontrolplanes_spec.yaml
 	$(YQ) -i '.conversion.webhook.clientConfig.service.namespace = "{{ .Values.kamajiNamespace }}"' ./charts/kamaji-crds/hack/kamaji.clastix.io_tenantcontrolplanes_spec.yaml
 

PROJECT

@@ -7,6 +7,15 @@ plugins:
 projectName: operator
 repo: github.com/clastix/kamaji
 resources:
+- api:
+    crdVersion: v1
+    namespaced: false
+  controller: true
+  domain: clastix.io
+  group: kamaji
+  kind: KubeconfigGenerator
+  path: github.com/clastix/kamaji/api/v1alpha1
+  version: v1alpha1
 - api:
     crdVersion: v1
     namespaced: true

api/v1alpha1/kubeconfiggenerator_types.go

@@ -0,0 +1,91 @@
+// Copyright 2022 Clastix Labs
+// SPDX-License-Identifier: Apache-2.0
+
+package v1alpha1
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+var (
+	ManagedByLabel  = "kamaji.clastix.io/managed-by"
+	ManagedForLabel = "kamaji.clastix.io/managed-for"
+)
+
+//+kubebuilder:object:root=true
+//+kubebuilder:subresource:status
+//+kubebuilder:printcolumn:name="Age",type="date",JSONPath=".metadata.creationTimestamp",description="Age"
+//+kubebuilder:metadata:annotations={"cert-manager.io/inject-ca-from=kamaji-system/kamaji-serving-cert"}
+//+kubebuilder:resource:scope=Cluster,shortName=kc,categories=kamaji
+
+// KubeconfigGenerator is the Schema for the kubeconfiggenerators API.
+type KubeconfigGenerator struct {
+	metav1.TypeMeta   `json:",inline"`
+	metav1.ObjectMeta `json:"metadata,omitempty"`
+
+	Spec   KubeconfigGeneratorSpec   `json:"spec,omitempty"`
+	Status KubeconfigGeneratorStatus `json:"status,omitempty"`
+}
+
+// CompoundValue allows defining a static, or a dynamic value.
+// Options are mutually exclusive, just one should be picked up.
+// +kubebuilder:validation:XValidation:rule="(has(self.stringValue) || has(self.fromDefinition)) && !(has(self.stringValue) && has(self.fromDefinition))",message="Either stringValue or fromDefinition must be set, but not both."
+type CompoundValue struct {
+	// StringValue is a static string value.
+	StringValue string `json:"stringValue,omitempty"`
+	// FromDefinition is used to generate a dynamic value,
+	// it uses the dot notation to access fields from the referenced TenantControlPlane object:
+	// e.g.: metadata.name
+	FromDefinition string `json:"fromDefinition,omitempty"`
+}
+
+type KubeconfigGeneratorSpec struct {
+	// NamespaceSelector is used to filter Namespaces from which the generator should extract TenantControlPlane objects.
+	NamespaceSelector metav1.LabelSelector `json:"namespaceSelector,omitempty"`
+	// TenantControlPlaneSelector is used to filter the TenantControlPlane objects that should be address by the generator.
+	TenantControlPlaneSelector metav1.LabelSelector `json:"tenantControlPlaneSelector,omitempty"`
+	// Groups is resolved a set of strings used to assign the x509 organisations field.
+	// It will be recognised by Kubernetes as user groups.
+	Groups []CompoundValue `json:"groups,omitempty"`
+	// User resolves to a string to identify the client, assigned to the x509 Common Name field.
+	User CompoundValue `json:"user"`
+	// ControlPlaneEndpointFrom is the key used to extract the Tenant Control Plane endpoint that must be used by the generator.
+	// The targeted Secret is the `${TCP}-admin-kubeconfig` one, default to `admin.svc`.
+	//+kubebuilder:default="admin.svc"
+	ControlPlaneEndpointFrom string `json:"controlPlaneEndpointFrom,omitempty"`
+}
+
+type KubeconfigGeneratorStatusError struct {
+	// Resource is the Namespaced name of the errored resource.
+	//+kubebuilder:validation:Required
+	Resource string `json:"resource"`
+	// Message is the error message recorded upon the last generator run.
+	//+kubebuilder:validation:Required
+	Message string `json:"message"`
+}
+
+// KubeconfigGeneratorStatus defines the observed state of KubeconfigGenerator.
+type KubeconfigGeneratorStatus struct {
+	// Resources is the sum of targeted TenantControlPlane objects.
+	//+kubebuilder:default=0
+	Resources int `json:"resources"`
+	// AvailableResources is the sum of successfully generated resources.
+	// In case of a different value compared to Resources, check the field errors.
+	//+kubebuilder:default=0
+	AvailableResources int `json:"availableResources"`
+	// Errors is the list of failed kubeconfig generations.
+	Errors []KubeconfigGeneratorStatusError `json:"errors,omitempty"`
+}
+
+//+kubebuilder:object:root=true
+
+// KubeconfigGeneratorList contains a list of TenantControlPlane.
+type KubeconfigGeneratorList struct {
+	metav1.TypeMeta `json:",inline"`
+	metav1.ListMeta `json:"metadata,omitempty"`
+	Items           []KubeconfigGenerator `json:"items"`
+}
+
+func init() {
+	SchemeBuilder.Register(&KubeconfigGenerator{}, &KubeconfigGeneratorList{})
+}

api/v1alpha1/zz_generated.deepcopy.go

@@ -289,6 +289,21 @@ func (in *ClientCertificate) DeepCopy() *ClientCertificate {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *CompoundValue) DeepCopyInto(out *CompoundValue) {
+	*out = *in
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new CompoundValue.
+func (in *CompoundValue) DeepCopy() *CompoundValue {
+	if in == nil {
+		return nil
+	}
+	out := new(CompoundValue)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *ContentRef) DeepCopyInto(out *ContentRef) {
 	*out = *in
@@ -951,6 +966,123 @@ func (in *KubeadmPhasesStatus) DeepCopy() *KubeadmPhasesStatus {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *KubeconfigGenerator) DeepCopyInto(out *KubeconfigGenerator) {
+	*out = *in
+	out.TypeMeta = in.TypeMeta
+	in.ObjectMeta.DeepCopyInto(&out.ObjectMeta)
+	in.Spec.DeepCopyInto(&out.Spec)
+	in.Status.DeepCopyInto(&out.Status)
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new KubeconfigGenerator.
+func (in *KubeconfigGenerator) DeepCopy() *KubeconfigGenerator {
+	if in == nil {
+		return nil
+	}
+	out := new(KubeconfigGenerator)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyObject is an autogenerated deepcopy function, copying the receiver, creating a new runtime.Object.
+func (in *KubeconfigGenerator) DeepCopyObject() runtime.Object {
+	if c := in.DeepCopy(); c != nil {
+		return c
+	}
+	return nil
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *KubeconfigGeneratorList) DeepCopyInto(out *KubeconfigGeneratorList) {
+	*out = *in
+	out.TypeMeta = in.TypeMeta
+	in.ListMeta.DeepCopyInto(&out.ListMeta)
+	if in.Items != nil {
+		in, out := &in.Items, &out.Items
+		*out = make([]KubeconfigGenerator, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new KubeconfigGeneratorList.
+func (in *KubeconfigGeneratorList) DeepCopy() *KubeconfigGeneratorList {
+	if in == nil {
+		return nil
+	}
+	out := new(KubeconfigGeneratorList)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyObject is an autogenerated deepcopy function, copying the receiver, creating a new runtime.Object.
+func (in *KubeconfigGeneratorList) DeepCopyObject() runtime.Object {
+	if c := in.DeepCopy(); c != nil {
+		return c
+	}
+	return nil
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *KubeconfigGeneratorSpec) DeepCopyInto(out *KubeconfigGeneratorSpec) {
+	*out = *in
+	in.NamespaceSelector.DeepCopyInto(&out.NamespaceSelector)
+	in.TenantControlPlaneSelector.DeepCopyInto(&out.TenantControlPlaneSelector)
+	if in.Groups != nil {
+		in, out := &in.Groups, &out.Groups
+		*out = make([]CompoundValue, len(*in))
+		copy(*out, *in)
+	}
+	out.User = in.User
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new KubeconfigGeneratorSpec.
+func (in *KubeconfigGeneratorSpec) DeepCopy() *KubeconfigGeneratorSpec {
+	if in == nil {
+		return nil
+	}
+	out := new(KubeconfigGeneratorSpec)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *KubeconfigGeneratorStatus) DeepCopyInto(out *KubeconfigGeneratorStatus) {
+	*out = *in
+	if in.Errors != nil {
+		in, out := &in.Errors, &out.Errors
+		*out = make([]KubeconfigGeneratorStatusError, len(*in))
+		copy(*out, *in)
+	}
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new KubeconfigGeneratorStatus.
+func (in *KubeconfigGeneratorStatus) DeepCopy() *KubeconfigGeneratorStatus {
+	if in == nil {
+		return nil
+	}
+	out := new(KubeconfigGeneratorStatus)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *KubeconfigGeneratorStatusError) DeepCopyInto(out *KubeconfigGeneratorStatusError) {
+	*out = *in
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new KubeconfigGeneratorStatusError.
+func (in *KubeconfigGeneratorStatusError) DeepCopy() *KubeconfigGeneratorStatusError {
+	if in == nil {
+		return nil
+	}
+	out := new(KubeconfigGeneratorStatusError)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *KubeconfigStatus) DeepCopyInto(out *KubeconfigStatus) {
 	*out = *in

charts/kamaji-crds/hack/kamaji.clastix.io_kubeconfiggenerators_spec.yaml

@@ -0,0 +1,214 @@
+group: kamaji.clastix.io
+names:
+  categories:
+    - kamaji
+  kind: KubeconfigGenerator
+  listKind: KubeconfigGeneratorList
+  plural: kubeconfiggenerators
+  shortNames:
+    - kc
+  singular: kubeconfiggenerator
+scope: Cluster
+versions:
+  - additionalPrinterColumns:
+      - description: Age
+        jsonPath: .metadata.creationTimestamp
+        name: Age
+        type: date
+    name: v1alpha1
+    schema:
+      openAPIV3Schema:
+        description: KubeconfigGenerator is the Schema for the kubeconfiggenerators API.
+        properties:
+          apiVersion:
+            description: |-
+              APIVersion defines the versioned schema of this representation of an object.
+              Servers should convert recognized schemas to the latest internal value, and
+              may reject unrecognized values.
+              More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources
+            type: string
+          kind:
+            description: |-
+              Kind is a string value representing the REST resource this object represents.
+              Servers may infer this from the endpoint the client submits requests to.
+              Cannot be updated.
+              In CamelCase.
+              More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
+            type: string
+          metadata:
+            type: object
+          spec:
+            properties:
+              controlPlaneEndpointFrom:
+                default: admin.svc
+                description: |-
+                  ControlPlaneEndpointFrom is the key used to extract the Tenant Control Plane endpoint that must be used by the generator.
+                  The targeted Secret is the `${TCP}-admin-kubeconfig` one, default to `admin.svc`.
+                type: string
+              groups:
+                description: |-
+                  Groups is resolved a set of strings used to assign the x509 organisations field.
+                  It will be recognised by Kubernetes as user groups.
+                items:
+                  description: |-
+                    CompoundValue allows defining a static, or a dynamic value.
+                    Options are mutually exclusive, just one should be picked up.
+                  properties:
+                    fromDefinition:
+                      description: |-
+                        FromDefinition is used to generate a dynamic value,
+                        it uses the dot notation to access fields from the referenced TenantControlPlane object:
+                        e.g.: metadata.name
+                      type: string
+                    stringValue:
+                      description: StringValue is a static string value.
+                      type: string
+                  type: object
+                  x-kubernetes-validations:
+                    - message: Either stringValue or fromDefinition must be set, but not both.
+                      rule: (has(self.stringValue) || has(self.fromDefinition)) && !(has(self.stringValue) && has(self.fromDefinition))
+                type: array
+              namespaceSelector:
+                description: NamespaceSelector is used to filter Namespaces from which the generator should extract TenantControlPlane objects.
+                properties:
+                  matchExpressions:
+                    description: matchExpressions is a list of label selector requirements. The requirements are ANDed.
+                    items:
+                      description: |-
+                        A label selector requirement is a selector that contains values, a key, and an operator that
+                        relates the key and values.
+                      properties:
+                        key:
+                          description: key is the label key that the selector applies to.
+                          type: string
+                        operator:
+                          description: |-
+                            operator represents a key's relationship to a set of values.
+                            Valid operators are In, NotIn, Exists and DoesNotExist.
+                          type: string
+                        values:
+                          description: |-
+                            values is an array of string values. If the operator is In or NotIn,
+                            the values array must be non-empty. If the operator is Exists or DoesNotExist,
+                            the values array must be empty. This array is replaced during a strategic
+                            merge patch.
+                          items:
+                            type: string
+                          type: array
+                          x-kubernetes-list-type: atomic
+                      required:
+                        - key
+                        - operator
+                      type: object
+                    type: array
+                    x-kubernetes-list-type: atomic
+                  matchLabels:
+                    additionalProperties:
+                      type: string
+                    description: |-
+                      matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+                      map is equivalent to an element of matchExpressions, whose key field is "key", the
+                      operator is "In", and the values array contains only "value". The requirements are ANDed.
+                    type: object
+                type: object
+                x-kubernetes-map-type: atomic
+              tenantControlPlaneSelector:
+                description: TenantControlPlaneSelector is used to filter the TenantControlPlane objects that should be address by the generator.
+                properties:
+                  matchExpressions:
+                    description: matchExpressions is a list of label selector requirements. The requirements are ANDed.
+                    items:
+                      description: |-
+                        A label selector requirement is a selector that contains values, a key, and an operator that
+                        relates the key and values.
+                      properties:
+                        key:
+                          description: key is the label key that the selector applies to.
+                          type: string
+                        operator:
+                          description: |-
+                            operator represents a key's relationship to a set of values.
+                            Valid operators are In, NotIn, Exists and DoesNotExist.
+                          type: string
+                        values:
+                          description: |-
+                            values is an array of string values. If the operator is In or NotIn,
+                            the values array must be non-empty. If the operator is Exists or DoesNotExist,
+                            the values array must be empty. This array is replaced during a strategic
+                            merge patch.
+                          items:
+                            type: string
+                          type: array
+                          x-kubernetes-list-type: atomic
+                      required:
+                        - key
+                        - operator
+                      type: object
+                    type: array
+                    x-kubernetes-list-type: atomic
+                  matchLabels:
+                    additionalProperties:
+                      type: string
+                    description: |-
+                      matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+                      map is equivalent to an element of matchExpressions, whose key field is "key", the
+                      operator is "In", and the values array contains only "value". The requirements are ANDed.
+                    type: object
+                type: object
+                x-kubernetes-map-type: atomic
+              user:
+                description: User resolves to a string to identify the client, assigned to the x509 Common Name field.
+                properties:
+                  fromDefinition:
+                    description: |-
+                      FromDefinition is used to generate a dynamic value,
+                      it uses the dot notation to access fields from the referenced TenantControlPlane object:
+                      e.g.: metadata.name
+                    type: string
+                  stringValue:
+                    description: StringValue is a static string value.
+                    type: string
+                type: object
+                x-kubernetes-validations:
+                  - message: Either stringValue or fromDefinition must be set, but not both.
+                    rule: (has(self.stringValue) || has(self.fromDefinition)) && !(has(self.stringValue) && has(self.fromDefinition))
+            required:
+              - user
+            type: object
+          status:
+            description: KubeconfigGeneratorStatus defines the observed state of KubeconfigGenerator.
+            properties:
+              availableResources:
+                default: 0
+                description: |-
+                  AvailableResources is the sum of successfully generated resources.
+                  In case of a different value compared to Resources, check the field errors.
+                type: integer
+              errors:
+                description: Errors is the list of failed kubeconfig generations.
+                items:
+                  properties:
+                    message:
+                      description: Message is the error message recorded upon the last generator run.
+                      type: string
+                    resource:
+                      description: Resource is the Namespaced name of the errored resource.
+                      type: string
+                  required:
+                    - message
+                    - resource
+                  type: object
+                type: array
+              resources:
+                default: 0
+                description: Resources is the sum of targeted TenantControlPlane objects.
+                type: integer
+            required:
+              - availableResources
+              - resources
+            type: object
+        type: object
+    served: true
+    storage: true
+    subresources:
+      status: {}

charts/kamaji-crds/templates/kamaji.clastix.io_kubeconfiggenerators.yaml

@@ -0,0 +1,10 @@
+apiVersion: apiextensions.k8s.io/v1
+kind: CustomResourceDefinition
+metadata:
+  annotations:
+    cert-manager.io/inject-ca-from: {{ include "kamaji-crds.certManagerAnnotation" . }}
+  labels:
+    {{- include "kamaji-crds.labels" . | nindent 4 }}
+  name: kubeconfiggenerators.kamaji.clastix.io
+spec:
+  {{ tpl (.Files.Get "hack/kamaji.clastix.io_kubeconfiggenerators_spec.yaml") . | nindent 2 }}

charts/kamaji/README.md

@@ -83,6 +83,24 @@ Here the values you can override:
 | image.tag | string | `nil` | Overrides the image tag whose default is the chart appVersion. |
 | imagePullSecrets | list | `[]` |  |
 | kamaji-etcd | object | `{"clusterDomain":"cluster.local","datastore":{"enabled":true,"name":"default"},"deploy":true,"fullnameOverride":"kamaji-etcd"}` | Subchart: See https://github.com/clastix/kamaji-etcd/blob/master/charts/kamaji-etcd/values.yaml |
+| kubeconfigGenerator.affinity | object | `{}` | Kubernetes affinity rules to apply to Kubeconfig Generator controller pods |
+| kubeconfigGenerator.enableLeaderElect | bool | `true` | Enables the leader election. |
+| kubeconfigGenerator.enabled | bool | `false` | Toggle to deploy the Kubeconfig Generator Deployment. |
+| kubeconfigGenerator.extraArgs | list | `[]` | A list of extra arguments to add to the Kubeconfig Generator controller default ones. |
+| kubeconfigGenerator.fullnameOverride | string | `""` |  |
+| kubeconfigGenerator.healthProbeBindAddress | string | `":8081"` | The address the probe endpoint binds to. |
+| kubeconfigGenerator.loggingDevel.enable | bool | `false` | Development Mode defaults(encoder=consoleEncoder,logLevel=Debug,stackTraceLevel=Warn). Production Mode defaults(encoder=jsonEncoder,logLevel=Info,stackTraceLevel=Error) |
+| kubeconfigGenerator.nodeSelector | object | `{}` | Kubernetes node selector rules to schedule Kubeconfig Generator controller |
+| kubeconfigGenerator.podAnnotations | object | `{}` | The annotations to apply to the Kubeconfig Generator controller pods. |
+| kubeconfigGenerator.podSecurityContext | object | `{"runAsNonRoot":true}` | The securityContext to apply to the Kubeconfig Generator controller pods. |
+| kubeconfigGenerator.replicaCount | int | `2` | The number of the pod replicas for the Kubeconfig Generator controller. |
+| kubeconfigGenerator.resources.limits.cpu | string | `"200m"` |  |
+| kubeconfigGenerator.resources.limits.memory | string | `"512Mi"` |  |
+| kubeconfigGenerator.resources.requests.cpu | string | `"200m"` |  |
+| kubeconfigGenerator.resources.requests.memory | string | `"512Mi"` |  |
+| kubeconfigGenerator.securityContext | object | `{"allowPrivilegeEscalation":false}` | The securityContext to apply to the Kubeconfig Generator controller container only. |
+| kubeconfigGenerator.serviceAccountOverride | string | `""` | The name of the service account to use. If not set, the root Kamaji one will be used. |
+| kubeconfigGenerator.tolerations | list | `[]` | Kubernetes node taints that the Kubeconfig Generator controller pods would tolerate |
 | livenessProbe | object | `{"httpGet":{"path":"/healthz","port":"healthcheck"},"initialDelaySeconds":15,"periodSeconds":20}` | The livenessProbe for the controller container |
 | loggingDevel.enable | bool | `false` | Development Mode defaults(encoder=consoleEncoder,logLevel=Debug,stackTraceLevel=Warn). Production Mode defaults(encoder=jsonEncoder,logLevel=Info,stackTraceLevel=Error) (default false) |
 | metricsBindAddress | string | `":8080"` | The address the metric endpoint binds to. (default ":8080") |

charts/kamaji/controller-gen/clusterrole.yaml

@@ -1,3 +1,11 @@
+- apiGroups:
+    - ""
+  resources:
+    - namespaces
+  verbs:
+    - get
+    - list
+    - watch
 - apiGroups:
     - apps
   resources:
@@ -51,6 +59,7 @@
     - kamaji.clastix.io
   resources:
     - datastores/status
+    - kubeconfiggenerators/status
     - tenantcontrolplanes/status
   verbs:
     - get
@@ -59,6 +68,18 @@
 - apiGroups:
     - kamaji.clastix.io
   resources:
+    - kubeconfiggenerators
+  verbs:
+    - create
+    - get
+    - list
+    - patch
+    - update
+    - watch
+- apiGroups:
+    - kamaji.clastix.io
+  resources:
+    - kubeconfiggenerators/finalizers
     - tenantcontrolplanes/finalizers
   verbs:
     - update

charts/kamaji/crds/kamaji.clastix.io_kubeconfiggenerators.yaml

@@ -0,0 +1,222 @@
+apiVersion: apiextensions.k8s.io/v1
+kind: CustomResourceDefinition
+metadata:
+  annotations:
+    cert-manager.io/inject-ca-from: kamaji-system/kamaji-serving-cert
+    controller-gen.kubebuilder.io/version: v0.16.1
+  name: kubeconfiggenerators.kamaji.clastix.io
+spec:
+  group: kamaji.clastix.io
+  names:
+    categories:
+      - kamaji
+    kind: KubeconfigGenerator
+    listKind: KubeconfigGeneratorList
+    plural: kubeconfiggenerators
+    shortNames:
+      - kc
+    singular: kubeconfiggenerator
+  scope: Cluster
+  versions:
+    - additionalPrinterColumns:
+        - description: Age
+          jsonPath: .metadata.creationTimestamp
+          name: Age
+          type: date
+      name: v1alpha1
+      schema:
+        openAPIV3Schema:
+          description: KubeconfigGenerator is the Schema for the kubeconfiggenerators API.
+          properties:
+            apiVersion:
+              description: |-
+                APIVersion defines the versioned schema of this representation of an object.
+                Servers should convert recognized schemas to the latest internal value, and
+                may reject unrecognized values.
+                More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources
+              type: string
+            kind:
+              description: |-
+                Kind is a string value representing the REST resource this object represents.
+                Servers may infer this from the endpoint the client submits requests to.
+                Cannot be updated.
+                In CamelCase.
+                More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
+              type: string
+            metadata:
+              type: object
+            spec:
+              properties:
+                controlPlaneEndpointFrom:
+                  default: admin.svc
+                  description: |-
+                    ControlPlaneEndpointFrom is the key used to extract the Tenant Control Plane endpoint that must be used by the generator.
+                    The targeted Secret is the `${TCP}-admin-kubeconfig` one, default to `admin.svc`.
+                  type: string
+                groups:
+                  description: |-
+                    Groups is resolved a set of strings used to assign the x509 organisations field.
+                    It will be recognised by Kubernetes as user groups.
+                  items:
+                    description: |-
+                      CompoundValue allows defining a static, or a dynamic value.
+                      Options are mutually exclusive, just one should be picked up.
+                    properties:
+                      fromDefinition:
+                        description: |-
+                          FromDefinition is used to generate a dynamic value,
+                          it uses the dot notation to access fields from the referenced TenantControlPlane object:
+                          e.g.: metadata.name
+                        type: string
+                      stringValue:
+                        description: StringValue is a static string value.
+                        type: string
+                    type: object
+                    x-kubernetes-validations:
+                      - message: Either stringValue or fromDefinition must be set, but not both.
+                        rule: (has(self.stringValue) || has(self.fromDefinition)) && !(has(self.stringValue) && has(self.fromDefinition))
+                  type: array
+                namespaceSelector:
+                  description: NamespaceSelector is used to filter Namespaces from which the generator should extract TenantControlPlane objects.
+                  properties:
+                    matchExpressions:
+                      description: matchExpressions is a list of label selector requirements. The requirements are ANDed.
+                      items:
+                        description: |-
+                          A label selector requirement is a selector that contains values, a key, and an operator that
+                          relates the key and values.
+                        properties:
+                          key:
+                            description: key is the label key that the selector applies to.
+                            type: string
+                          operator:
+                            description: |-
+                              operator represents a key's relationship to a set of values.
+                              Valid operators are In, NotIn, Exists and DoesNotExist.
+                            type: string
+                          values:
+                            description: |-
+                              values is an array of string values. If the operator is In or NotIn,
+                              the values array must be non-empty. If the operator is Exists or DoesNotExist,
+                              the values array must be empty. This array is replaced during a strategic
+                              merge patch.
+                            items:
+                              type: string
+                            type: array
+                            x-kubernetes-list-type: atomic
+                        required:
+                          - key
+                          - operator
+                        type: object
+                      type: array
+                      x-kubernetes-list-type: atomic
+                    matchLabels:
+                      additionalProperties:
+                        type: string
+                      description: |-
+                        matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+                        map is equivalent to an element of matchExpressions, whose key field is "key", the
+                        operator is "In", and the values array contains only "value". The requirements are ANDed.
+                      type: object
+                  type: object
+                  x-kubernetes-map-type: atomic
+                tenantControlPlaneSelector:
+                  description: TenantControlPlaneSelector is used to filter the TenantControlPlane objects that should be address by the generator.
+                  properties:
+                    matchExpressions:
+                      description: matchExpressions is a list of label selector requirements. The requirements are ANDed.
+                      items:
+                        description: |-
+                          A label selector requirement is a selector that contains values, a key, and an operator that
+                          relates the key and values.
+                        properties:
+                          key:
+                            description: key is the label key that the selector applies to.
+                            type: string
+                          operator:
+                            description: |-
+                              operator represents a key's relationship to a set of values.
+                              Valid operators are In, NotIn, Exists and DoesNotExist.
+                            type: string
+                          values:
+                            description: |-
+                              values is an array of string values. If the operator is In or NotIn,
+                              the values array must be non-empty. If the operator is Exists or DoesNotExist,
+                              the values array must be empty. This array is replaced during a strategic
+                              merge patch.
+                            items:
+                              type: string
+                            type: array
+                            x-kubernetes-list-type: atomic
+                        required:
+                          - key
+                          - operator
+                        type: object
+                      type: array
+                      x-kubernetes-list-type: atomic
+                    matchLabels:
+                      additionalProperties:
+                        type: string
+                      description: |-
+                        matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+                        map is equivalent to an element of matchExpressions, whose key field is "key", the
+                        operator is "In", and the values array contains only "value". The requirements are ANDed.
+                      type: object
+                  type: object
+                  x-kubernetes-map-type: atomic
+                user:
+                  description: User resolves to a string to identify the client, assigned to the x509 Common Name field.
+                  properties:
+                    fromDefinition:
+                      description: |-
+                        FromDefinition is used to generate a dynamic value,
+                        it uses the dot notation to access fields from the referenced TenantControlPlane object:
+                        e.g.: metadata.name
+                      type: string
+                    stringValue:
+                      description: StringValue is a static string value.
+                      type: string
+                  type: object
+                  x-kubernetes-validations:
+                    - message: Either stringValue or fromDefinition must be set, but not both.
+                      rule: (has(self.stringValue) || has(self.fromDefinition)) && !(has(self.stringValue) && has(self.fromDefinition))
+              required:
+                - user
+              type: object
+            status:
+              description: KubeconfigGeneratorStatus defines the observed state of KubeconfigGenerator.
+              properties:
+                availableResources:
+                  default: 0
+                  description: |-
+                    AvailableResources is the sum of successfully generated resources.
+                    In case of a different value compared to Resources, check the field errors.
+                  type: integer
+                errors:
+                  description: Errors is the list of failed kubeconfig generations.
+                  items:
+                    properties:
+                      message:
+                        description: Message is the error message recorded upon the last generator run.
+                        type: string
+                      resource:
+                        description: Resource is the Namespaced name of the errored resource.
+                        type: string
+                    required:
+                      - message
+                      - resource
+                    type: object
+                  type: array
+                resources:
+                  default: 0
+                  description: Resources is the sum of targeted TenantControlPlane objects.
+                  type: integer
+              required:
+                - availableResources
+                - resources
+              type: object
+          type: object
+      served: true
+      storage: true
+      subresources:
+        status: {}

charts/kamaji/templates/_helpers.tpl

@@ -89,3 +89,15 @@ Create the name of the cert-manager Certificate
 {{- define "kamaji.certificateName" -}}
 {{- printf "%s-serving-cert" (include "kamaji.fullname" .) }}
 {{- end }}
+
+
+{{/*
+Kubeconfig Generator Deployment name.
+*/}}
+{{- define "kamaji.kubeconfigGeneratorName" -}}
+{{- if .Values.kubeconfigGenerator.fullnameOverride }}
+{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
+{{- else }}
+{{- printf "%s-%s" .Release.Name "kubeconfig-generator" | trunc 63 | trimSuffix "-" }}
+{{- end }}
+{{- end }}

charts/kamaji/templates/kubeconfiggenerator-deployment.yaml

@@ -0,0 +1,54 @@
+{{- if .Values.kubeconfigGenerator.enabled }}
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  labels:
+    {{- include "kamaji.labels" . | nindent 4 }}
+  name: {{ include "kamaji.kubeconfigGeneratorName" . }}
+  namespace: {{ .Release.Namespace }}
+spec:
+  replicas: {{ .Values.kubeconfigGenerator.replicaCount }}
+  selector:
+    matchLabels:
+      {{- include "kamaji.selectorLabels" . | nindent 6 }}
+  template:
+    metadata:
+      {{- with .Values.kubeconfigGenerator.podAnnotations }}
+      annotations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      labels:
+        {{- include "kamaji.selectorLabels" . | nindent 8 }}
+    spec:
+      securityContext:
+        {{- toYaml .Values.kubeconfigGenerator.podSecurityContext | nindent 8 }}
+      serviceAccountName: {{ default .Values.kubeconfigGenerator.serviceAccountOverride (include "kamaji.serviceAccountName" .) }}
+      containers:
+        - args:
+          - kubeconfig-generator
+          - --health-probe-bind-address={{ .Values.kubeconfigGenerator.healthProbeBindAddress }}
+          - --leader-elect={{ .Values.kubeconfigGenerator.enableLeaderElect }}
+          {{- if .Values.kubeconfigGenerator.loggingDevel.enable }}- --zap-devel{{- end }}
+          {{- with .Values.kubeconfigGenerator.extraArgs }}
+          {{- toYaml . | nindent 10 }}
+          {{- end }}
+          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
+          imagePullPolicy: {{ .Values.image.pullPolicy }}
+          name: controller
+          resources:
+            {{- toYaml .Values.kubeconfigGenerator.resources | nindent 12 }}
+          securityContext:
+            {{- toYaml .Values.kubeconfigGenerator.securityContext | nindent 12 }}
+      {{- with .Values.kubeconfigGenerator.nodeSelector }}
+      nodeSelector:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.kubeconfigGenerator.affinity }}
+      affinity:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.kubeconfigGenerator.tolerations }}
+      tolerations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+{{- end }}

charts/kamaji/values.yaml

@@ -111,4 +111,48 @@ kamaji-etcd:
 # -- Disable the analytics traces collection
 telemetry:
   disabled: false
-  
+
+kubeconfigGenerator:
+  # -- Toggle to deploy the Kubeconfig Generator Deployment.
+  enabled: false
+  fullnameOverride: ""
+  # -- The number of the pod replicas for the Kubeconfig Generator controller.
+  replicaCount: 2
+  # -- The annotations to apply to the Kubeconfig Generator controller pods.
+  podAnnotations: {}
+  # -- The securityContext to apply to the Kubeconfig Generator controller pods.
+  podSecurityContext:
+    runAsNonRoot: true
+  # -- The name of the service account to use. If not set, the root Kamaji one will be used.
+  serviceAccountOverride: ""
+  # -- The address the probe endpoint binds to.
+  healthProbeBindAddress: ":8081"
+  # -- Enables the leader election.
+  enableLeaderElect: true
+  loggingDevel:
+    # -- Development Mode defaults(encoder=consoleEncoder,logLevel=Debug,stackTraceLevel=Warn). Production Mode defaults(encoder=jsonEncoder,logLevel=Info,stackTraceLevel=Error)
+    enable: false
+  # -- A list of extra arguments to add to the Kubeconfig Generator controller default ones.
+  extraArgs: []
+  resources:
+    limits:
+      cpu: 200m
+      memory: 512Mi
+    requests:
+      cpu: 200m
+      memory: 512Mi
+  # -- The securityContext to apply to the Kubeconfig Generator controller container only.
+  securityContext:
+    allowPrivilegeEscalation: false
+    # capabilities:
+    #   drop:
+    #   - ALL
+    # readOnlyRootFilesystem: true
+    # runAsNonRoot: true
+    # runAsUser: 1000
+  # -- Kubernetes node selector rules to schedule Kubeconfig Generator controller
+  nodeSelector: {}
+  # -- Kubernetes node taints that the Kubeconfig Generator controller pods would tolerate
+  tolerations: []
+  # -- Kubernetes affinity rules to apply to Kubeconfig Generator controller pods
+  affinity: {}

cmd/kubeconfig-generator/cmd.go

@@ -0,0 +1,167 @@
+// Copyright 2022 Clastix Labs
+// SPDX-License-Identifier: Apache-2.0
+
+package kubeconfiggenerator
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	goRuntime "runtime"
+	"time"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/rest"
+	"k8s.io/klog/v2"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/cache"
+	"sigs.k8s.io/controller-runtime/pkg/event"
+	"sigs.k8s.io/controller-runtime/pkg/healthz"
+	"sigs.k8s.io/controller-runtime/pkg/log/zap"
+	metricsserver "sigs.k8s.io/controller-runtime/pkg/metrics/server"
+
+	"github.com/clastix/kamaji/controllers"
+	"github.com/clastix/kamaji/internal"
+)
+
+func NewCmd(scheme *runtime.Scheme) *cobra.Command {
+	// CLI flags
+	var (
+		metricsBindAddress            string
+		healthProbeBindAddress        string
+		leaderElect                   bool
+		controllerReconcileTimeout    time.Duration
+		cacheResyncPeriod             time.Duration
+		managerNamespace              string
+		certificateExpirationDeadline time.Duration
+	)
+
+	cmd := &cobra.Command{
+		Use:           "kubeconfig-generator",
+		Short:         "Start the Kubeconfig Generator manager",
+		SilenceErrors: false,
+		SilenceUsage:  true,
+		PreRunE: func(*cobra.Command, []string) error {
+			// Avoid polluting stdout with useless details by the underlying klog implementations
+			klog.SetOutput(io.Discard)
+			klog.LogToStderr(false)
+
+			if certificateExpirationDeadline < 24*time.Hour {
+				return fmt.Errorf("certificate expiration deadline must be at least 24 hours")
+			}
+
+			return nil
+		},
+		RunE: func(*cobra.Command, []string) error {
+			ctx := ctrl.SetupSignalHandler()
+
+			setupLog := ctrl.Log.WithName("kubeconfig-generator")
+
+			setupLog.Info(fmt.Sprintf("Kamaji version %s %s%s", internal.GitTag, internal.GitCommit, internal.GitDirty))
+			setupLog.Info(fmt.Sprintf("Build from: %s", internal.GitRepo))
+			setupLog.Info(fmt.Sprintf("Build date: %s", internal.BuildTime))
+			setupLog.Info(fmt.Sprintf("Go Version: %s", goRuntime.Version()))
+			setupLog.Info(fmt.Sprintf("Go OS/Arch: %s/%s", goRuntime.GOOS, goRuntime.GOARCH))
+
+			ctrlOpts := ctrl.Options{
+				Scheme: scheme,
+				Metrics: metricsserver.Options{
+					BindAddress: metricsBindAddress,
+				},
+				HealthProbeBindAddress:  healthProbeBindAddress,
+				LeaderElection:          leaderElect,
+				LeaderElectionNamespace: managerNamespace,
+				LeaderElectionID:        "kubeconfiggenerator.kamaji.clastix.io",
+				NewCache: func(config *rest.Config, opts cache.Options) (cache.Cache, error) {
+					opts.SyncPeriod = &cacheResyncPeriod
+
+					return cache.New(config, opts)
+				},
+			}
+
+			triggerChan := make(chan event.GenericEvent)
+
+			mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrlOpts)
+			if err != nil {
+				setupLog.Error(err, "unable to start manager")
+
+				return err
+			}
+
+			setupLog.Info("setting probes")
+			{
+				if err = mgr.AddHealthzCheck("healthz", healthz.Ping); err != nil {
+					setupLog.Error(err, "unable to set up health check")
+
+					return err
+				}
+				if err = mgr.AddReadyzCheck("readyz", healthz.Ping); err != nil {
+					setupLog.Error(err, "unable to set up ready check")
+
+					return err
+				}
+			}
+
+			certController := &controllers.CertificateLifecycle{Channel: triggerChan, Deadline: certificateExpirationDeadline}
+			certController.EnqueueFn = certController.EnqueueForKubeconfigGenerator
+			if err = certController.SetupWithManager(mgr); err != nil {
+				setupLog.Error(err, "unable to create controller", "controller", "CertificateLifecycle")
+
+				return err
+			}
+
+			if err = (&controllers.KubeconfigGeneratorWatcher{
+				Client:        mgr.GetClient(),
+				GeneratorChan: triggerChan,
+			}).SetupWithManager(mgr); err != nil {
+				setupLog.Error(err, "unable to create controller", "controller", "KubeconfigGeneratorWatcher")
+
+				return err
+			}
+
+			if err = (&controllers.KubeconfigGeneratorReconciler{
+				Client:            mgr.GetClient(),
+				NotValidThreshold: certificateExpirationDeadline,
+				CertificateChan:   triggerChan,
+			}).SetupWithManager(mgr); err != nil {
+				setupLog.Error(err, "unable to create controller", "controller", "KubeconfigGenerator")
+
+				return err
+			}
+
+			setupLog.Info("starting manager")
+			if err = mgr.Start(ctx); err != nil {
+				setupLog.Error(err, "problem running manager")
+
+				return err
+			}
+
+			return nil
+		},
+	}
+	// Setting zap logger
+	zapfs := flag.NewFlagSet("zap", flag.ExitOnError)
+	opts := zap.Options{
+		Development: true,
+	}
+	opts.BindFlags(zapfs)
+	cmd.Flags().AddGoFlagSet(zapfs)
+	ctrl.SetLogger(zap.New(zap.UseFlagOptions(&opts)))
+	// Setting CLI flags
+	cmd.Flags().StringVar(&metricsBindAddress, "metrics-bind-address", ":8090", "The address the metric endpoint binds to.")
+	cmd.Flags().StringVar(&healthProbeBindAddress, "health-probe-bind-address", ":8091", "The address the probe endpoint binds to.")
+	cmd.Flags().BoolVar(&leaderElect, "leader-elect", true, "Enable leader election for controller manager. Enabling this will ensure there is only one active controller manager.")
+	cmd.Flags().DurationVar(&controllerReconcileTimeout, "controller-reconcile-timeout", 30*time.Second, "The reconciliation request timeout before the controller withdraw the external resource calls, such as dealing with the Datastore, or the Tenant Control Plane API endpoint.")
+	cmd.Flags().DurationVar(&cacheResyncPeriod, "cache-resync-period", 10*time.Hour, "The controller-runtime.Manager cache resync period.")
+	cmd.Flags().StringVar(&managerNamespace, "pod-namespace", os.Getenv("POD_NAMESPACE"), "The Kubernetes Namespace on which the Operator is running in, required for the TenantControlPlane migration jobs.")
+	cmd.Flags().DurationVar(&certificateExpirationDeadline, "certificate-expiration-deadline", 24*time.Hour, "Define the deadline upon certificate expiration to start the renewal process, cannot be less than a 24 hours.")
+
+	cobra.OnInitialize(func() {
+		viper.AutomaticEnv()
+	})
+
+	return cmd
+}

cmd/manager/cmd.go

@@ -4,6 +4,7 @@
 package manager
 
 import (
+	"context"
 	"flag"
 	"fmt"
 	"io"
@@ -62,8 +63,6 @@ func NewCmd(scheme *runtime.Scheme) *cobra.Command {
 		webhookCAPath string
 	)
 
-	ctx := ctrl.SetupSignalHandler()
-
 	cmd := &cobra.Command{
 		Use:           "manager",
 		Short:         "Start the Kamaji Kubernetes Operator",
@@ -86,7 +85,7 @@ func NewCmd(scheme *runtime.Scheme) *cobra.Command {
 				return fmt.Errorf("unable to read webhook CA: %w", err)
 			}
 
-			if err = datastoreutils.CheckExists(ctx, scheme, datastore); err != nil {
+			if err = datastoreutils.CheckExists(context.Background(), scheme, datastore); err != nil {
 				return err
 			}
 
@@ -97,6 +96,8 @@ func NewCmd(scheme *runtime.Scheme) *cobra.Command {
 			return nil
 		},
 		RunE: func(*cobra.Command, []string) error {
+			ctx := ctrl.SetupSignalHandler()
+
 			setupLog := ctrl.Log.WithName("setup")
 
 			setupLog.Info(fmt.Sprintf("Kamaji version %s %s%s", internal.GitTag, internal.GitCommit, internal.GitDirty))
@@ -193,7 +194,10 @@ func NewCmd(scheme *runtime.Scheme) *cobra.Command {
 				}
 			}
 
-			if err = (&controllers.CertificateLifecycle{Channel: certChannel, Deadline: certificateExpirationDeadline}).SetupWithManager(mgr); err != nil {
+			certController := &controllers.CertificateLifecycle{Channel: certChannel, Deadline: certificateExpirationDeadline}
+			certController.EnqueueFn = certController.EnqueueForTenantControlPlane
+
+			if err = certController.SetupWithManager(mgr); err != nil {
 				setupLog.Error(err, "unable to create controller", "controller", "CertificateLifecycle")
 
 				return err

config/samples/kamaji_v1alpha1_kubeconfiggenerator.yaml

@@ -0,0 +1,21 @@
+apiVersion: kamaji.clastix.io/v1alpha1
+kind: KubeconfigGenerator
+metadata:
+  name: tenant
+spec:
+  controlPlaneEndpointFrom: admin.conf
+  groups:
+    - stringValue: custom.group.tld
+    - fromDefinition: metadata.namespace
+  namespaceSelector:
+    matchExpressions:
+      - key: kubernetes.io/metadata.name
+        operator: Exists
+        values: []
+  tenantControlPlaneSelector:
+    matchExpressions:
+      - key: tenant.clastix.io
+        operator: Exists
+        values: []
+  user:
+    fromDefinition: metadata.name

controllers/certificate_lifecycle_controller.go

@@ -31,8 +31,9 @@ import (
 )
 
 type CertificateLifecycle struct {
-	Channel  chan event.GenericEvent
-	Deadline time.Duration
+	Channel   chan event.GenericEvent
+	Deadline  time.Duration
+	EnqueueFn func(secret *corev1.Secret)
 
 	client client.Client
 }
@@ -91,12 +92,7 @@ func (s *CertificateLifecycle) Reconcile(ctx context.Context, request reconcile.
 	if deadline.After(crt.NotAfter) {
 		logger.Info("certificate near expiration, must be rotated")
 
-		s.Channel <- event.GenericEvent{Object: &kamajiv1alpha1.TenantControlPlane{
-			ObjectMeta: metav1.ObjectMeta{
-				Name:      secret.GetOwnerReferences()[0].Name,
-				Namespace: secret.Namespace,
-			},
-		}}
+		s.EnqueueFn(&secret)
 
 		logger.Info("certificate rotation triggered")
 
@@ -110,6 +106,35 @@ func (s *CertificateLifecycle) Reconcile(ctx context.Context, request reconcile.
 	return reconcile.Result{RequeueAfter: after}, nil
 }
 
+func (s *CertificateLifecycle) EnqueueForTenantControlPlane(secret *corev1.Secret) {
+	for _, or := range secret.GetOwnerReferences() {
+		if or.Kind != "TenantControlPlane" {
+			continue
+		}
+
+		s.Channel <- event.GenericEvent{Object: &kamajiv1alpha1.TenantControlPlane{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      or.Name,
+				Namespace: secret.Namespace,
+			},
+		}}
+	}
+}
+
+func (s *CertificateLifecycle) EnqueueForKubeconfigGenerator(secret *corev1.Secret) {
+	for _, or := range secret.GetOwnerReferences() {
+		if or.Kind != "KubeconfigGenerator" {
+			continue
+		}
+
+		s.Channel <- event.GenericEvent{Object: &kamajiv1alpha1.TenantControlPlane{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: or.Name,
+			},
+		}}
+	}
+}
+
 func (s *CertificateLifecycle) extractCertificateFromBareSecret(secret corev1.Secret) (*x509.Certificate, error) {
 	var crt *x509.Certificate
 	var err error

controllers/kubeconfiggenerator_controller.go

@@ -0,0 +1,444 @@
+// Copyright 2022 Clastix Labs
+// SPDX-License-Identifier: Apache-2.0
+
+package controllers
+
+import (
+	"bytes"
+	"context"
+	"crypto/x509"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/pkg/errors"
+	corev1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/sets"
+	clientcmdapiv1 "k8s.io/client-go/tools/clientcmd/api/v1"
+	certutil "k8s.io/client-go/util/cert"
+	"k8s.io/client-go/util/keyutil"
+	"k8s.io/client-go/util/workqueue"
+	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
+	"k8s.io/kubernetes/cmd/kubeadm/app/util"
+	"k8s.io/kubernetes/cmd/kubeadm/app/util/pkiutil"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+	"sigs.k8s.io/controller-runtime/pkg/event"
+	"sigs.k8s.io/controller-runtime/pkg/handler"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+	"sigs.k8s.io/controller-runtime/pkg/source"
+
+	kamajiv1alpha1 "github.com/clastix/kamaji/api/v1alpha1"
+	"github.com/clastix/kamaji/controllers/utils"
+	"github.com/clastix/kamaji/internal/constants"
+	"github.com/clastix/kamaji/internal/crypto"
+	"github.com/clastix/kamaji/internal/resources"
+	"github.com/clastix/kamaji/internal/utilities"
+)
+
+type KubeconfigGeneratorReconciler struct {
+	Client            client.Client
+	NotValidThreshold time.Duration
+	CertificateChan   chan event.GenericEvent
+}
+
+//+kubebuilder:rbac:groups="",resources=namespaces,verbs=get;list;watch
+//+kubebuilder:rbac:groups=kamaji.clastix.io,resources=kubeconfiggenerators,verbs=get;list;watch;create;update;patch
+//+kubebuilder:rbac:groups=kamaji.clastix.io,resources=kubeconfiggenerators/status,verbs=get;update;patch
+//+kubebuilder:rbac:groups=kamaji.clastix.io,resources=kubeconfiggenerators/finalizers,verbs=update
+
+func (r *KubeconfigGeneratorReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
+	logger := log.FromContext(ctx)
+
+	logger.Info("reconciling resource")
+
+	var generator kamajiv1alpha1.KubeconfigGenerator
+	if err := r.Client.Get(ctx, req.NamespacedName, &generator); err != nil {
+		if apierrors.IsNotFound(err) {
+			logger.Info("resource may have been deleted, skipping")
+
+			return ctrl.Result{}, nil
+		}
+
+		logger.Error(err, "cannot retrieve the required resource")
+
+		return ctrl.Result{}, err
+	}
+
+	if utils.IsPaused(&generator) {
+		logger.Info("paused reconciliation, no further actions")
+
+		return ctrl.Result{}, nil
+	}
+
+	status, err := r.handle(ctx, &generator)
+	if err != nil {
+		logger.Error(err, "cannot handle the request")
+
+		return ctrl.Result{}, err
+	}
+
+	generator.Status = status
+
+	if statusErr := r.Client.Status().Update(ctx, &generator); statusErr != nil {
+		logger.Error(statusErr, "cannot update resource status")
+
+		return ctrl.Result{}, statusErr
+	}
+
+	logger.Info("reconciling completed")
+
+	return ctrl.Result{}, nil
+}
+
+func (r *KubeconfigGeneratorReconciler) handle(ctx context.Context, generator *kamajiv1alpha1.KubeconfigGenerator) (kamajiv1alpha1.KubeconfigGeneratorStatus, error) {
+	nsSelector, nsErr := metav1.LabelSelectorAsSelector(&generator.Spec.NamespaceSelector)
+	if nsErr != nil {
+		return kamajiv1alpha1.KubeconfigGeneratorStatus{}, errors.Wrap(nsErr, "NamespaceSelector contains an error")
+	}
+
+	var namespaceList corev1.NamespaceList
+	if err := r.Client.List(ctx, &namespaceList, &client.ListOptions{LabelSelector: nsSelector}); err != nil {
+		return kamajiv1alpha1.KubeconfigGeneratorStatus{}, errors.Wrap(err, "cannot filter Namespace objects using provided selector")
+	}
+
+	var targets []kamajiv1alpha1.TenantControlPlane
+
+	for _, ns := range namespaceList.Items {
+		tcpSelector, tcpErr := metav1.LabelSelectorAsSelector(&generator.Spec.TenantControlPlaneSelector)
+		if tcpErr != nil {
+			return kamajiv1alpha1.KubeconfigGeneratorStatus{}, errors.Wrap(tcpErr, "TenantControlPlaneSelector contains an error")
+		}
+
+		var tcpList kamajiv1alpha1.TenantControlPlaneList
+		if err := r.Client.List(ctx, &tcpList, &client.ListOptions{Namespace: ns.GetName(), LabelSelector: tcpSelector}); err != nil {
+			return kamajiv1alpha1.KubeconfigGeneratorStatus{}, errors.Wrap(err, "cannot filter TenantControlPlane objects using provided selector")
+		}
+
+		targets = append(targets, tcpList.Items...)
+	}
+
+	sort.Slice(targets, func(i, j int) bool {
+		return client.ObjectKeyFromObject(&targets[i]).String() < client.ObjectKeyFromObject(&targets[j]).String()
+	})
+
+	status := kamajiv1alpha1.KubeconfigGeneratorStatus{
+		Resources:          len(targets),
+		AvailableResources: len(targets),
+	}
+
+	for _, tcp := range targets {
+		if err := r.process(ctx, generator, tcp); err != nil {
+			status.Errors = append(status.Errors, *err)
+			status.AvailableResources--
+		}
+	}
+
+	return status, nil
+}
+
+func (r *KubeconfigGeneratorReconciler) process(ctx context.Context, generator *kamajiv1alpha1.KubeconfigGenerator, tcp kamajiv1alpha1.TenantControlPlane) *kamajiv1alpha1.KubeconfigGeneratorStatusError {
+	statusErr := kamajiv1alpha1.KubeconfigGeneratorStatusError{
+		Resource: client.ObjectKeyFromObject(&tcp).String(),
+	}
+
+	var adminSecret corev1.Secret
+
+	if tcp.Status.KubeConfig.Admin.SecretName == "" {
+		statusErr.Message = "the admin kubeconfig is not yet generated"
+
+		return &statusErr
+	}
+
+	if err := r.Client.Get(ctx, types.NamespacedName{Name: tcp.Status.KubeConfig.Admin.SecretName, Namespace: tcp.GetNamespace()}, &adminSecret); err != nil {
+		statusErr.Message = fmt.Sprintf("an error occurred retrieving the admin Kubeconfig: %s", err.Error())
+
+		return &statusErr
+	}
+
+	kubeconfigTmpl, kcErr := utilities.DecodeKubeconfig(adminSecret, generator.Spec.ControlPlaneEndpointFrom)
+	if kcErr != nil {
+		statusErr.Message = fmt.Sprintf("unable to decode Kubeconfig template: %s", kcErr.Error())
+
+		return &statusErr
+	}
+
+	uMap, uErr := runtime.DefaultUnstructuredConverter.ToUnstructured(&tcp)
+	if uErr != nil {
+		statusErr.Message = fmt.Sprintf("cannot convert the resource to a map: %s", uErr)
+
+		return &statusErr
+	}
+
+	var user string
+	groups := sets.New[string]()
+
+	for _, group := range generator.Spec.Groups {
+		switch {
+		case group.StringValue != "":
+			groups.Insert(group.StringValue)
+		case group.FromDefinition != "":
+			v, ok, vErr := unstructured.NestedString(uMap, strings.Split(group.FromDefinition, ".")...)
+			switch {
+			case vErr != nil:
+				statusErr.Message = fmt.Sprintf("cannot run NestedString %q due to an error: %s", group.FromDefinition, vErr.Error())
+
+				return &statusErr
+			case !ok:
+				statusErr.Message = fmt.Sprintf("provided dot notation %q is not found", group.FromDefinition)
+
+				return &statusErr
+			default:
+				groups.Insert(v)
+			}
+		default:
+			statusErr.Message = "at least a StringValue or FromDefinition Group value must be provided"
+
+			return &statusErr
+		}
+	}
+
+	switch {
+	case generator.Spec.User.StringValue != "":
+		user = generator.Spec.User.StringValue
+	case generator.Spec.User.FromDefinition != "":
+		v, ok, vErr := unstructured.NestedString(uMap, strings.Split(generator.Spec.User.FromDefinition, ".")...)
+
+		switch {
+		case vErr != nil:
+			statusErr.Message = fmt.Sprintf("cannot run NestedString %q due to an error: %s", generator.Spec.User.FromDefinition, vErr.Error())
+
+			return &statusErr
+		case !ok:
+			statusErr.Message = fmt.Sprintf("provided dot notation %q is not found", generator.Spec.User.FromDefinition)
+
+			return &statusErr
+		default:
+			user = v
+		}
+	default:
+		statusErr.Message = "at least a StringValue or FromDefinition for the user field must be provided"
+
+		return &statusErr
+	}
+
+	var resultSecret corev1.Secret
+	resultSecret.SetName(tcp.Name + "-" + generator.Name)
+	resultSecret.SetNamespace(tcp.Namespace)
+
+	objectKey := client.ObjectKeyFromObject(&resultSecret)
+
+	if err := r.Client.Get(ctx, objectKey, &resultSecret); err != nil {
+		if !apierrors.IsNotFound(err) {
+			statusErr.Message = fmt.Sprintf("the secret %q cannot be generated", objectKey.String())
+
+			return &statusErr
+		}
+
+		if generateErr := r.generate(ctx, generator, &resultSecret, kubeconfigTmpl, &tcp, groups, user); generateErr != nil {
+			statusErr.Message = fmt.Sprintf("an error occurred generating the %q Secret: %s", objectKey.String(), generateErr.Error())
+
+			return &statusErr
+		}
+
+		return nil
+	}
+
+	isValid, validateErr := r.isValid(&resultSecret, kubeconfigTmpl, groups, user)
+	switch {
+	case !isValid:
+		if generateErr := r.generate(ctx, generator, &resultSecret, kubeconfigTmpl, &tcp, groups, user); generateErr != nil {
+			statusErr.Message = fmt.Sprintf("an error occurred regenerating the %q Secret: %s", objectKey.String(), generateErr.Error())
+
+			return &statusErr
+		}
+
+		return nil
+	case validateErr != nil:
+		statusErr.Message = fmt.Sprintf("an error occurred checking validation for %q Secret: %s", objectKey.String(), validateErr.Error())
+
+		return &statusErr
+	default:
+		return nil
+	}
+}
+
+func (r *KubeconfigGeneratorReconciler) generate(ctx context.Context, generator *kamajiv1alpha1.KubeconfigGenerator, secret *corev1.Secret, tmpl *clientcmdapiv1.Config, tcp *kamajiv1alpha1.TenantControlPlane, groups sets.Set[string], user string) error {
+	_, config, err := resources.GetKubeadmManifestDeps(ctx, r.Client, tcp)
+	if err != nil {
+		return err
+	}
+
+	clientCertConfig := pkiutil.CertConfig{
+		Config: certutil.Config{
+			CommonName:   user,
+			Organization: groups.UnsortedList(),
+			Usages:       []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth},
+		},
+		NotAfter:            util.StartTimeUTC().Add(kubeadmconstants.CertificateValidityPeriod),
+		EncryptionAlgorithm: config.InitConfiguration.ClusterConfiguration.EncryptionAlgorithmType(),
+	}
+
+	var caSecret corev1.Secret
+	if caErr := r.Client.Get(ctx, types.NamespacedName{Namespace: tcp.Namespace, Name: tcp.Status.Certificates.CA.SecretName}, &caSecret); caErr != nil {
+		return errors.Wrap(caErr, "cannot retrieve Certificate Authority")
+	}
+
+	caCert, crtErr := crypto.ParseCertificateBytes(caSecret.Data[kubeadmconstants.CACertName])
+	if crtErr != nil {
+		return errors.Wrap(crtErr, "cannot parse Certificate Authority certificate")
+	}
+
+	caKey, keyErr := crypto.ParsePrivateKeyBytes(caSecret.Data[kubeadmconstants.CAKeyName])
+	if keyErr != nil {
+		return errors.Wrap(keyErr, "cannot parse Certificate Authority key")
+	}
+
+	clientCert, clientKey, err := pkiutil.NewCertAndKey(caCert, caKey, &clientCertConfig)
+
+	contextUserName := generator.Name
+
+	for name := range tmpl.AuthInfos {
+		tmpl.AuthInfos[name].Name = contextUserName
+		tmpl.AuthInfos[name].AuthInfo.ClientCertificateData = pkiutil.EncodeCertPEM(clientCert)
+		tmpl.AuthInfos[name].AuthInfo.ClientKeyData, err = keyutil.MarshalPrivateKeyToPEM(clientKey)
+		if err != nil {
+			return errors.Wrap(err, "cannot marshal private key to PEM")
+		}
+	}
+
+	for name := range tmpl.Contexts {
+		tmpl.Contexts[name].Name = contextUserName
+		tmpl.Contexts[name].Context.AuthInfo = contextUserName
+	}
+
+	tmpl.CurrentContext = contextUserName
+
+	_, err = utilities.CreateOrUpdateWithConflict(ctx, r.Client, secret, func() error {
+		labels := secret.GetLabels()
+		if labels == nil {
+			labels = map[string]string{}
+		}
+
+		labels[kamajiv1alpha1.ManagedByLabel] = generator.Name
+		labels[kamajiv1alpha1.ManagedForLabel] = tcp.Name
+		labels[constants.ControllerLabelResource] = utilities.CertificateKubeconfigLabel
+
+		secret.SetLabels(labels)
+
+		if secret.Data == nil {
+			secret.Data = make(map[string][]byte)
+		}
+
+		secret.Data["value"], err = utilities.EncodeToYaml(tmpl)
+		if err != nil {
+			return errors.Wrap(err, "cannot encode generated Kubeconfig to YAML")
+		}
+
+		if utilities.IsRotationRequested(secret) {
+			utilities.SetLastRotationTimestamp(secret)
+		}
+
+		if orErr := controllerutil.SetOwnerReference(tcp, secret, r.Client.Scheme()); orErr != nil {
+			return orErr
+		}
+
+		return ctrl.SetControllerReference(tcp, secret, r.Client.Scheme())
+	})
+	if err != nil {
+		return errors.Wrap(err, "cannot create or update generated Kubeconfig")
+	}
+
+	return nil
+}
+
+func (r *KubeconfigGeneratorReconciler) isValid(secret *corev1.Secret, tmpl *clientcmdapiv1.Config, groups sets.Set[string], user string) (bool, error) {
+	if utilities.IsRotationRequested(secret) {
+		return false, nil
+	}
+
+	concrete, decodeErr := utilities.DecodeKubeconfig(*secret, "value")
+	if decodeErr != nil {
+		return false, decodeErr
+	}
+	// Checking Certificate Authority validity
+	switch {
+	case len(concrete.Clusters) != len(tmpl.Clusters):
+		return false, nil
+	default:
+		for i := range tmpl.Clusters {
+			if !bytes.Equal(tmpl.Clusters[i].Cluster.CertificateAuthorityData, concrete.Clusters[i].Cluster.CertificateAuthorityData) {
+				return false, nil
+			}
+
+			if tmpl.Clusters[i].Cluster.Server != concrete.Clusters[i].Cluster.Server {
+				return false, nil
+			}
+		}
+	}
+
+	for _, auth := range concrete.AuthInfos {
+		valid, vErr := crypto.IsValidCertificateKeyPairBytes(auth.AuthInfo.ClientCertificateData, auth.AuthInfo.ClientKeyData, r.NotValidThreshold)
+		if vErr != nil {
+			return false, vErr
+		}
+		if !valid {
+			return false, nil
+		}
+
+		crt, crtErr := crypto.ParseCertificateBytes(auth.AuthInfo.ClientCertificateData)
+		if crtErr != nil {
+			return false, crtErr
+		}
+
+		if crt.Subject.CommonName != user {
+			return false, nil
+		}
+
+		if !sets.New[string](crt.Subject.Organization...).Equal(groups) {
+			return false, nil
+		}
+	}
+
+	return true, nil
+}
+
+func (r *KubeconfigGeneratorReconciler) SetupWithManager(mgr manager.Manager) error {
+	return ctrl.NewControllerManagedBy(mgr).
+		For(&kamajiv1alpha1.KubeconfigGenerator{}).
+		WatchesRawSource(source.Channel(r.CertificateChan, handler.Funcs{GenericFunc: func(_ context.Context, genericEvent event.TypedGenericEvent[client.Object], w workqueue.TypedRateLimitingInterface[reconcile.Request]) {
+			w.AddRateLimited(ctrl.Request{
+				NamespacedName: types.NamespacedName{
+					Name: genericEvent.Object.GetName(),
+				},
+			})
+		}})).
+		Watches(&corev1.Secret{}, handler.TypedEnqueueRequestsFromMapFunc(func(ctx context.Context, object client.Object) []ctrl.Request {
+			if object.GetLabels() == nil {
+				return nil
+			}
+
+			v, found := object.GetLabels()[kamajiv1alpha1.ManagedByLabel]
+			if !found {
+				return nil
+			}
+
+			return []ctrl.Request{
+				{
+					NamespacedName: types.NamespacedName{
+						Name: v,
+					},
+				},
+			}
+		})).
+		Complete(r)
+}

controllers/kubeconfiggenerator_watcher.go

@@ -0,0 +1,75 @@
+// Copyright 2022 Clastix Labs
+// SPDX-License-Identifier: Apache-2.0
+
+package controllers
+
+import (
+	"context"
+
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/event"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+
+	kamajiv1alpha1 "github.com/clastix/kamaji/api/v1alpha1"
+)
+
+type KubeconfigGeneratorWatcher struct {
+	Client        client.Client
+	GeneratorChan chan event.GenericEvent
+}
+
+func (r *KubeconfigGeneratorWatcher) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
+	logger := log.FromContext(ctx)
+
+	logger.Info("reconciling resource")
+
+	var tcp kamajiv1alpha1.TenantControlPlane
+	if err := r.Client.Get(ctx, req.NamespacedName, &tcp); err != nil {
+		if apierrors.IsNotFound(err) {
+			logger.Info("resource may have been deleted, skipping")
+
+			return ctrl.Result{}, nil
+		}
+
+		logger.Error(err, "cannot retrieve the required resource")
+
+		return ctrl.Result{}, err
+	}
+
+	var generators kamajiv1alpha1.KubeconfigGeneratorList
+	if err := r.Client.List(ctx, &generators); err != nil {
+		logger.Error(err, "cannot list generators")
+
+		return ctrl.Result{}, err
+	}
+
+	for _, generator := range generators.Items {
+		sel, err := metav1.LabelSelectorAsSelector(&generator.Spec.TenantControlPlaneSelector)
+		if err != nil {
+			logger.Error(err, "cannot validate Selector", "generator", generator.Name)
+
+			return ctrl.Result{}, err
+		}
+
+		if sel.Matches(labels.Set(tcp.Labels)) {
+			logger.Info("pushing Generator", "generator", generator.Name)
+
+			r.GeneratorChan <- event.GenericEvent{
+				Object: &generator,
+			}
+		}
+	}
+
+	return ctrl.Result{}, nil
+}
+
+func (r *KubeconfigGeneratorWatcher) SetupWithManager(mgr manager.Manager) error {
+	return ctrl.NewControllerManagedBy(mgr).
+		For(&kamajiv1alpha1.TenantControlPlane{}).
+		Complete(r)
+}

docs/content/guides/kubeconfig-generator.md

@@ -0,0 +1,114 @@
+# Kubeconfig Generator
+
+The **Kubeconfig Generator** is a Kamaji extension that simplifies the distribution of Kubeconfig files for tenant clusters managed through Kamaji.
+
+Instead of manually exporting and editing credentials, the generator automates the creation of kubeconfigs aligned with your organizational policies.
+
+## Motivation
+
+When managing multiple Tenant Control Planes (TCPs), cluster administrators often face two challenges:
+
+1. **Consistency**: ensuring kubeconfigs are generated with the correct user identity, groups, and endpoints
+2. **Scalability**: distributing kubeconfigs to users across potentially dozens of tenant clusters without manual steps
+
+The `KubeconfigGenerator` resource addresses these problems by:
+
+- Selecting which TCPs to target via label selectors.
+- Defining how to build user and group identities in kubeconfigs.
+- Automatically maintaining kubeconfigs as new tenant clusters are created or updated.
+
+This provides a single, declarative way to manage kubeconfig lifecycle across all your tenants,
+especially convenient if those cases where an Identity Provider can't be used to delegate access to Tenant Control Plane clusters.
+
+## How it Works
+
+### Selection
+
+- `namespaceSelector` filters the namespaces from which Tenant Control Planes are discovered.
+- `tenantControlPlaneSelector` further refines which TCPs to include.
+
+### Identity Definition
+
+The `user` and `groups` fields use compound values, which can be either:
+
+- A static string (e.g., `developer`)
+- A dynamic reference resolved from the TCP object (e.g., `metadata.name`)
+
+This allows kubeconfigs to be tailored to the cluster’s context or a fixed organizational pattern.
+
+### Endpoint Resolution
+
+The generator pulls the API server endpoint from the TCP’s `admin` kubeconfig.
+
+By default it uses the `admin.svc` template, but this can be overridden with the `controlPlaneEndpointFrom` field.
+
+### Status and Errors
+
+The resource keeps track of how many kubeconfigs were attempted, how many succeeded,
+and provides detailed error reports for failed generations.
+
+## Typical Use Cases
+
+- **Platform Operators**: automatically distribute kubeconfigs to developers as new tenant clusters are provisioned.
+- **Multi-team Environments**: ensure each team gets kubeconfigs with the correct groups for RBAC authorization.
+- **Least Privilege Principle**: avoid distributing `cluster-admin` credentials with a fine-grained RBAC
+- **Dynamic Access**: use `fromDefinition` references to bind kubeconfig identities directly to tenant metadata
+ (e.g., prefixing users with the TCP's name).
+
+## Example Scenario
+
+A SaaS provider runs multiple Tenant Control Planes, each corresponding to a different customer.
+Instead of manually managing kubeconfigs for every customer environment, the operator defines a single `KubeconfigGenerator`:
+
+```yaml
+apiVersion: kamaji.clastix.io/v1alpha1
+kind: KubeconfigGenerator
+metadata:
+  name: tenant
+spec:
+  # Select only Tenant Control Planes living in namespaces
+  # labeled as production environments
+  namespaceSelector:
+    matchLabels:
+      environment: production
+  # Match all Tenant Control Planes in those namespaces
+  tenantControlPlaneSelector: {}
+  # Assign a static group "customer-admins"
+  groups:
+    - stringValue: "customer-admins"
+  # Derive the user identity dynamically from the TenantControlPlane metadata
+  user:
+    fromDefinition: "metadata.name"
+  # Use the public admin endpoint from the TCP’s kubeconfig
+  controlPlaneEndpointFrom: "admin.conf"
+```
+
+- Matches all TCPs in namespaces labeled `environment=production`.
+- Generates kubeconfigs with group `customer-admins`.
+- Derives the user identity from the TCP’s `metadata.name`.
+
+As new tenants are created, their kubeconfigs are generated automatically and kept up to date.
+
+```
+$: kubectl get secret --all-namespaces -l kamaji.clastix.io/managed-by=tenant
+NAMESPACE       NAME             TYPE     DATA   AGE
+alpha-tnt       env-133-tenant   Opaque   1      12h
+alpha-tnt       env-130-tenant   Opaque   1      2d
+bravo-tnt       prod-tenant      Opaque   1      2h
+charlie-tnt     stable-tenant    Opaque   1      1d
+```
+
+## Observability
+
+The generator exposes its status directly in the CRD:
+- `resources`: total number of TCPs targeted.
+- `availableResources`: successfully generated kubeconfigs.
+- `errors`: list of failed kubeconfig generations, including the affected resource and error message.
+
+This allows quick debugging and operational awareness.
+
+## Deployment
+
+The _Kubeconfig Generator_ is **not** enabled by default since it's still in experimental state.
+
+It can be enabled using the Helm value `kubeconfigGenerator.enabled=true` which is defaulted to `false`.

docs/content/reference/api.md

@@ -27271,6 +27271,8 @@ Resource Types:
 
 - [DataStore](#datastore)
 
+- [KubeconfigGenerator](#kubeconfiggenerator)
+
 - [TenantControlPlane](#tenantcontrolplane)
 
 
@@ -27985,6 +27987,415 @@ DataStoreStatus defines the observed state of DataStore.
       </tr></tbody>
 </table>
 
+### KubeconfigGenerator
+
+
+
+
+
+KubeconfigGenerator is the Schema for the kubeconfiggenerators API.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+      <td><b>apiVersion</b></td>
+      <td>string</td>
+      <td>kamaji.clastix.io/v1alpha1</td>
+      <td>true</td>
+      </tr>
+      <tr>
+      <td><b>kind</b></td>
+      <td>string</td>
+      <td>KubeconfigGenerator</td>
+      <td>true</td>
+      </tr>
+      <tr>
+      <td><b><a href="https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.20/#objectmeta-v1-meta">metadata</a></b></td>
+      <td>object</td>
+      <td>Refer to the Kubernetes API documentation for the fields of the `metadata` field.</td>
+      <td>true</td>
+      </tr><tr>
+        <td><b><a href="#kubeconfiggeneratorspec">spec</a></b></td>
+        <td>object</td>
+        <td>
+          <br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b><a href="#kubeconfiggeneratorstatus">status</a></b></td>
+        <td>object</td>
+        <td>
+          KubeconfigGeneratorStatus defines the observed state of KubeconfigGenerator.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspec">`KubeconfigGenerator.spec`</span>
+
+
+
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b><a href="#kubeconfiggeneratorspecuser">user</a></b></td>
+        <td>object</td>
+        <td>
+          User resolves to a string to identify the client, assigned to the x509 Common Name field.<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>controlPlaneEndpointFrom</b></td>
+        <td>string</td>
+        <td>
+          ControlPlaneEndpointFrom is the key used to extract the Tenant Control Plane endpoint that must be used by the generator.
+The targeted Secret is the `${TCP}-admin-kubeconfig` one, default to `admin.svc`.<br/>
+          <br/>
+            <i>Default</i>: admin.svc<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b><a href="#kubeconfiggeneratorspecgroupsindex">groups</a></b></td>
+        <td>[]object</td>
+        <td>
+          Groups is resolved a set of strings used to assign the x509 organisations field.
+It will be recognised by Kubernetes as user groups.<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b><a href="#kubeconfiggeneratorspecnamespaceselector">namespaceSelector</a></b></td>
+        <td>object</td>
+        <td>
+          NamespaceSelector is used to filter Namespaces from which the generator should extract TenantControlPlane objects.<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b><a href="#kubeconfiggeneratorspectenantcontrolplaneselector">tenantControlPlaneSelector</a></b></td>
+        <td>object</td>
+        <td>
+          TenantControlPlaneSelector is used to filter the TenantControlPlane objects that should be address by the generator.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspecuser">`KubeconfigGenerator.spec.user`</span>
+
+
+User resolves to a string to identify the client, assigned to the x509 Common Name field.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b>fromDefinition</b></td>
+        <td>string</td>
+        <td>
+          FromDefinition is used to generate a dynamic value,
+it uses the dot notation to access fields from the referenced TenantControlPlane object:
+e.g.: metadata.name<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b>stringValue</b></td>
+        <td>string</td>
+        <td>
+          StringValue is a static string value.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspecgroupsindex">`KubeconfigGenerator.spec.groups[index]`</span>
+
+
+CompoundValue allows defining a static, or a dynamic value.
+Options are mutually exclusive, just one should be picked up.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b>fromDefinition</b></td>
+        <td>string</td>
+        <td>
+          FromDefinition is used to generate a dynamic value,
+it uses the dot notation to access fields from the referenced TenantControlPlane object:
+e.g.: metadata.name<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b>stringValue</b></td>
+        <td>string</td>
+        <td>
+          StringValue is a static string value.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspecnamespaceselector">`KubeconfigGenerator.spec.namespaceSelector`</span>
+
+
+NamespaceSelector is used to filter Namespaces from which the generator should extract TenantControlPlane objects.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b><a href="#kubeconfiggeneratorspecnamespaceselectormatchexpressionsindex">matchExpressions</a></b></td>
+        <td>[]object</td>
+        <td>
+          matchExpressions is a list of label selector requirements. The requirements are ANDed.<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b>matchLabels</b></td>
+        <td>map[string]string</td>
+        <td>
+          matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+map is equivalent to an element of matchExpressions, whose key field is "key", the
+operator is "In", and the values array contains only "value". The requirements are ANDed.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspecnamespaceselectormatchexpressionsindex">`KubeconfigGenerator.spec.namespaceSelector.matchExpressions[index]`</span>
+
+
+A label selector requirement is a selector that contains values, a key, and an operator that
+relates the key and values.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b>key</b></td>
+        <td>string</td>
+        <td>
+          key is the label key that the selector applies to.<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>operator</b></td>
+        <td>string</td>
+        <td>
+          operator represents a key's relationship to a set of values.
+Valid operators are In, NotIn, Exists and DoesNotExist.<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>values</b></td>
+        <td>[]string</td>
+        <td>
+          values is an array of string values. If the operator is In or NotIn,
+the values array must be non-empty. If the operator is Exists or DoesNotExist,
+the values array must be empty. This array is replaced during a strategic
+merge patch.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspectenantcontrolplaneselector">`KubeconfigGenerator.spec.tenantControlPlaneSelector`</span>
+
+
+TenantControlPlaneSelector is used to filter the TenantControlPlane objects that should be address by the generator.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b><a href="#kubeconfiggeneratorspectenantcontrolplaneselectormatchexpressionsindex">matchExpressions</a></b></td>
+        <td>[]object</td>
+        <td>
+          matchExpressions is a list of label selector requirements. The requirements are ANDed.<br/>
+        </td>
+        <td>false</td>
+      </tr><tr>
+        <td><b>matchLabels</b></td>
+        <td>map[string]string</td>
+        <td>
+          matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
+map is equivalent to an element of matchExpressions, whose key field is "key", the
+operator is "In", and the values array contains only "value". The requirements are ANDed.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorspectenantcontrolplaneselectormatchexpressionsindex">`KubeconfigGenerator.spec.tenantControlPlaneSelector.matchExpressions[index]`</span>
+
+
+A label selector requirement is a selector that contains values, a key, and an operator that
+relates the key and values.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b>key</b></td>
+        <td>string</td>
+        <td>
+          key is the label key that the selector applies to.<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>operator</b></td>
+        <td>string</td>
+        <td>
+          operator represents a key's relationship to a set of values.
+Valid operators are In, NotIn, Exists and DoesNotExist.<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>values</b></td>
+        <td>[]string</td>
+        <td>
+          values is an array of string values. If the operator is In or NotIn,
+the values array must be non-empty. If the operator is Exists or DoesNotExist,
+the values array must be empty. This array is replaced during a strategic
+merge patch.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorstatus">`KubeconfigGenerator.status`</span>
+
+
+KubeconfigGeneratorStatus defines the observed state of KubeconfigGenerator.
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b>availableResources</b></td>
+        <td>integer</td>
+        <td>
+          AvailableResources is the sum of successfully generated resources.
+In case of a different value compared to Resources, check the field errors.<br/>
+          <br/>
+            <i>Default</i>: 0<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>resources</b></td>
+        <td>integer</td>
+        <td>
+          Resources is the sum of targeted TenantControlPlane objects.<br/>
+          <br/>
+            <i>Default</i>: 0<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b><a href="#kubeconfiggeneratorstatuserrorsindex">errors</a></b></td>
+        <td>[]object</td>
+        <td>
+          Errors is the list of failed kubeconfig generations.<br/>
+        </td>
+        <td>false</td>
+      </tr></tbody>
+</table>
+
+
+<span id="kubeconfiggeneratorstatuserrorsindex">`KubeconfigGenerator.status.errors[index]`</span>
+
+
+
+
+<table>
+    <thead>
+        <tr>
+            <th>Name</th>
+            <th>Type</th>
+            <th>Description</th>
+            <th>Required</th>
+        </tr>
+    </thead>
+    <tbody><tr>
+        <td><b>message</b></td>
+        <td>string</td>
+        <td>
+          Message is the error message recorded upon the last generator run.<br/>
+        </td>
+        <td>true</td>
+      </tr><tr>
+        <td><b>resource</b></td>
+        <td>string</td>
+        <td>
+          Resource is the Namespaced name of the errored resource.<br/>
+        </td>
+        <td>true</td>
+      </tr></tbody>
+</table>
+
 ### TenantControlPlane
 
 

docs/mkdocs.yml

@@ -77,6 +77,7 @@ nav:
   - guides/datastore-migration.md
   - guides/gitops.md
   - guides/console.md
+  - guides/kubeconfig-generator.md
   - guides/upgrade.md
   - guides/monitoring.md
   - guides/terraform.md

main.go

@@ -9,6 +9,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 
 	"github.com/clastix/kamaji/cmd"
+	kubeconfig_generator "github.com/clastix/kamaji/cmd/kubeconfig-generator"
 	"github.com/clastix/kamaji/cmd/manager"
 	"github.com/clastix/kamaji/cmd/migrate"
 )
@@ -16,9 +17,10 @@ import (
 func main() {
 	scheme := runtime.NewScheme()
 
-	root, mgr, migrator := cmd.NewCmd(scheme), manager.NewCmd(scheme), migrate.NewCmd(scheme)
+	root, mgr, migrator, kubeconfigGenerator := cmd.NewCmd(scheme), manager.NewCmd(scheme), migrate.NewCmd(scheme), kubeconfig_generator.NewCmd(scheme)
 	root.AddCommand(mgr)
 	root.AddCommand(migrator)
+	root.AddCommand(kubeconfigGenerator)
 
 	if err := root.Execute(); err != nil {
 		os.Exit(1)