[WIP][DO NOT REVIEW] 🌱 Experiment vsim

test/infrastructure/vcsim/README.md

@@ -69,7 +69,8 @@ source vcsim.env
 $ source vcsim.env
 
 # Then you are ready to create a workload cluster
-$ cat <your template> | envsubst | kubectl apply -f -
+make envsubst
+$ cat <your template> | hack/tools/bin/envsubst | kubectl apply -f -
 ```
 
 #### Using govc with vcsim

test/infrastructure/vcsim/api/v1alpha1/vmoperatordependencies_types_test.go

@@ -0,0 +1,65 @@
+package v1alpha1
+
+import (
+	"fmt"
+	"testing"
+
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"sigs.k8s.io/yaml"
+)
+
+func TestVMOperatorDependencies_SetVCenterFromVCenterSimulator(t *testing.T) {
+	type fields struct {
+		TypeMeta   v1.TypeMeta
+		ObjectMeta v1.ObjectMeta
+		Spec       VMOperatorDependenciesSpec
+		Status     VMOperatorDependenciesStatus
+	}
+	type args struct {
+		vCenterSimulator *VCenterSimulator
+	}
+	tests := []struct {
+		name   string
+		fields fields
+		args   args
+	}{
+		{
+			args: args{
+				vCenterSimulator: &VCenterSimulator{
+					Status: VCenterSimulatorStatus{
+						Host:       "Host",
+						Username:   "Username",
+						Password:   "Password",
+						Thumbprint: "Thumbprint",
+					},
+				},
+			},
+			fields: fields{
+				TypeMeta: v1.TypeMeta{
+					Kind:       "VMOperatorDependencies",
+					APIVersion: GroupVersion.String(),
+				},
+				ObjectMeta: v1.ObjectMeta{
+					Name:      "name",
+					Namespace: "namespace",
+				},
+				Spec:   VMOperatorDependenciesSpec{},
+				Status: VMOperatorDependenciesStatus{},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			d := &VMOperatorDependencies{
+				TypeMeta:   tt.fields.TypeMeta,
+				ObjectMeta: tt.fields.ObjectMeta,
+				Spec:       tt.fields.Spec,
+				Status:     tt.fields.Status,
+			}
+			d.SetVCenterFromVCenterSimulator(tt.args.vCenterSimulator)
+
+			foo, _ := yaml.Marshal(d)
+			fmt.Println(string(foo))
+		})
+	}
+}

test/infrastructure/vcsim/controllers/backends/containers/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package containers implements backend for ControlPlaneEndpoint and VirtualMachines implemented using containers
+// running on a host machine (inspired from CAPD).
+package containers

test/infrastructure/vcsim/controllers/backends/controlplaneendpoint.go

@@ -0,0 +1,30 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package backends
+
+import (
+	"context"
+
+	ctrl "sigs.k8s.io/controller-runtime"
+
+	vcsimv1 "sigs.k8s.io/cluster-api-provider-vsphere/test/infrastructure/vcsim/api/v1alpha1"
+)
+
+type ControlPlaneEndpointReconciler interface {
+	ReconcileNormal(ctx context.Context, controlPlaneEndpoint *vcsimv1.ControlPlaneEndpoint) (ctrl.Result, error)
+	ReconcileDelete(ctx context.Context, controlPlaneEndpoint *vcsimv1.ControlPlaneEndpoint) (ctrl.Result, error)
+}

test/infrastructure/vcsim/controllers/backends/inmemory/controlplaneendpoint.go

@@ -0,0 +1,75 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package inmemory
+
+import (
+	"context"
+
+	"github.com/pkg/errors"
+	"k8s.io/klog/v2"
+	inmemoryruntime "sigs.k8s.io/cluster-api/test/infrastructure/inmemory/pkg/runtime"
+	inmemoryserver "sigs.k8s.io/cluster-api/test/infrastructure/inmemory/pkg/server"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
+
+	vcsimv1 "sigs.k8s.io/cluster-api-provider-vsphere/test/infrastructure/vcsim/api/v1alpha1"
+)
+
+type ControlPlaneEndpointReconciler struct {
+	InMemoryManager inmemoryruntime.Manager
+	APIServerMux    *inmemoryserver.WorkloadClustersMux
+	PodIP           string
+}
+
+func (r *ControlPlaneEndpointReconciler) ReconcileNormal(ctx context.Context, controlPlaneEndpoint *vcsimv1.ControlPlaneEndpoint) (ctrl.Result, error) {
+	log := ctrl.LoggerFrom(ctx)
+	log.Info("Reconciling VCSim ControlPlaneEndpoint")
+
+	// Initialize a listener for the workload cluster.
+	// IMPORTANT: The fact that both the listener and the resourceGroup for a workload cluster have
+	// the same name is used as assumptions in other part of the implementation.
+	listenerName := klog.KObj(controlPlaneEndpoint).String()
+	listener, err := r.APIServerMux.InitWorkloadClusterListener(listenerName)
+	if err != nil {
+		return ctrl.Result{}, errors.Wrapf(err, "failed to init the listener for the control plane endpoint")
+	}
+
+	controlPlaneEndpoint.Status.Host = r.PodIP // NOTE: we are replacing the listener ip with the pod ip so it will be accessible from other pods as well
+	controlPlaneEndpoint.Status.Port = listener.Port()
+
+	return ctrl.Result{}, nil
+}
+
+func (r *ControlPlaneEndpointReconciler) ReconcileDelete(ctx context.Context, controlPlaneEndpoint *vcsimv1.ControlPlaneEndpoint) (ctrl.Result, error) {
+	log := ctrl.LoggerFrom(ctx)
+	log.Info("Reconciling delete VCSim ControlPlaneEndpoint")
+	listenerName := klog.KObj(controlPlaneEndpoint).String()
+
+	// Delete the resource group hosting all the cloud resources belonging the workload cluster;
+	if resourceGroup, err := r.APIServerMux.ResourceGroupByWorkloadCluster(listenerName); err == nil {
+		r.InMemoryManager.DeleteResourceGroup(resourceGroup)
+	}
+
+	// Delete the listener for the workload cluster;
+	if err := r.APIServerMux.DeleteWorkloadClusterListener(listenerName); err != nil {
+		return ctrl.Result{}, errors.Wrapf(err, "failed to delete the listener for the control plane endpoint")
+	}
+
+	controllerutil.RemoveFinalizer(controlPlaneEndpoint, vcsimv1.ControlPlaneEndpointFinalizer)
+
+	return ctrl.Result{}, nil
+}

test/infrastructure/vcsim/controllers/backends/inmemory/doc.go

@@ -0,0 +1,18 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package inmemory implements backend for ControlPlaneEndpoint and VirtualMachines implemented using CAPI inmemory test utils.
+package inmemory