azure: Implement DeleteInstance for rolling update

pkg/instancegroups/instancegroups.go

@@ -476,7 +476,8 @@ func (c *RollingUpdateCluster) reconcileInstanceGroup() error {
 	if c.Cluster.Spec.GetCloudProvider() != api.CloudProviderOpenstack &&
 		c.Cluster.Spec.GetCloudProvider() != api.CloudProviderHetzner &&
 		c.Cluster.Spec.GetCloudProvider() != api.CloudProviderScaleway &&
-		c.Cluster.Spec.GetCloudProvider() != api.CloudProviderDO {
+		c.Cluster.Spec.GetCloudProvider() != api.CloudProviderDO &&
+		c.Cluster.Spec.GetCloudProvider() != api.CloudProviderAzure {
 		return nil
 	}
 	rto := fi.RunTasksOptions{}

upup/pkg/fi/cloudup/azure/azure_cloud.go

@@ -20,6 +20,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"strings"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/azidentity"
 	"k8s.io/klog/v2"
@@ -192,7 +193,9 @@ func (c *azureCloudImplementation) FindVNetInfo(id, resourceGroup string) (*fi.V
 }
 
 func (c *azureCloudImplementation) DeleteInstance(i *cloudinstances.CloudInstance) error {
-	return errors.New("DeleteInstance not implemented on azureCloud")
+	vmssName := i.CloudInstanceGroup.HumanName
+	instanceID := strings.TrimPrefix(i.ID, vmssName+"_")
+	return c.vmscaleSetVMsClient.Delete(context.TODO(), "my.k8s", vmssName, instanceID)
 }
 
 // DeregisterInstance drains a cloud instance and loadbalancers.

upup/pkg/fi/cloudup/azure/status_test.go

@@ -67,6 +67,17 @@ func (c *mockVMScaleSetVMsClient) List(ctx context.Context, resourceGroupName, v
 	return c.vms, nil
 }
 
+func (c *mockVMScaleSetVMsClient) Delete(ctx context.Context, resourceGroupName, vmssName, instanceID string) error {
+	var l []*compute.VirtualMachineScaleSetVM
+	for _, vm := range c.vms {
+		if *vm.ID != instanceID {
+			l = append(l, vm)
+		}
+	}
+	c.vms = l
+	return nil
+}
+
 func TestFindEtcdStatus(t *testing.T) {
 	clusterName := "my-cluster"
 	c := &azureCloudImplementation{

upup/pkg/fi/cloudup/azure/vmscalesetvm.go

@@ -27,6 +27,7 @@ import (
 // VMScaleSetVMsClient is a client for managing VMs in VM Scale Sets.
 type VMScaleSetVMsClient interface {
 	List(ctx context.Context, resourceGroupName, vmssName string) ([]*compute.VirtualMachineScaleSetVM, error)
+	Delete(ctx context.Context, resourceGroupName, vmssName, instanceId string) error
 }
 
 type vmScaleSetVMsClientImpl struct {
@@ -48,6 +49,17 @@ func (c *vmScaleSetVMsClientImpl) List(ctx context.Context, resourceGroupName, v
 	return l, nil
 }
 
+func (c *vmScaleSetVMsClientImpl) Delete(ctx context.Context, resourceGroupName, vmssName, instanceId string) error {
+	future, err := c.c.BeginDelete(ctx, resourceGroupName, vmssName, instanceId, nil)
+	if err != nil {
+		return fmt.Errorf("deleting VMSS VM: %w", err)
+	}
+	if _, err = future.PollUntilDone(ctx, nil); err != nil {
+		return fmt.Errorf("waiting for VMSS VM deletion completion: %w", err)
+	}
+	return nil
+}
+
 func newVMScaleSetVMsClientImpl(subscriptionID string, cred *azidentity.DefaultAzureCredential) (*vmScaleSetVMsClientImpl, error) {
 	c, err := compute.NewVirtualMachineScaleSetVMsClient(subscriptionID, cred, nil)
 	if err != nil {

upup/pkg/fi/cloudup/azuretasks/testing.go

@@ -463,6 +463,13 @@ func (c *MockVMScaleSetVMsClient) List(ctx context.Context, resourceGroupName, v
 	return l, nil
 }
 
+// Delete deletes a VM Scale Set VMs.
+func (c *MockVMScaleSetVMsClient) Delete(ctx context.Context, resourceGroupName, vmssName, instanceID string) error {
+	// Ignore resourceGroupName and vmssName for simplicity.
+	delete(c.VMs, instanceID)
+	return nil
+}
+
 // MockDisksClient is a mock implementation of disk client.
 type MockDisksClient struct {
 	Disks map[string]*compute.Disk