codegen + updated headers + refactoring after reviews

pkg/model/bootstrapscript.go

@@ -26,6 +26,7 @@ import (
 	"strconv"
 	"strings"
 
+	"k8s.io/apimachinery/pkg/util/errors"
 	"k8s.io/klog/v2"
 	"k8s.io/kops/pkg/apis/kops/model"
 	"k8s.io/kops/upup/pkg/fi/utils"
@@ -210,35 +211,40 @@ func (b *BootstrapScript) buildEnvironmentVariables(cluster *kops.Cluster) (map[
 	}
 
 	if cluster.Spec.GetCloudProvider() == kops.CloudProviderScaleway {
+		errList := []error(nil)
 
 		region, err := scw.ParseRegion(os.Getenv("SCW_DEFAULT_REGION"))
 		if err != nil {
-			return nil, fmt.Errorf("error parsing SCW_DEFAULT_REGION: %w", err)
+			errList = append(errList, fmt.Errorf("error parsing SCW_DEFAULT_REGION: %w", err))
 		}
-		env["SCW_DEFAULT_REGION"] = string(region)
-
 		zone, err := scw.ParseZone(os.Getenv("SCW_DEFAULT_ZONE"))
 		if err != nil {
-			return nil, fmt.Errorf("error parsing SCW_DEFAULT_ZONE: %w", err)
+			errList = append(errList, fmt.Errorf("error parsing SCW_DEFAULT_ZONE: %w", err))
 		}
-		env["SCW_DEFAULT_ZONE"] = string(zone)
 
+		// We make sure that the credentials env vars are defined
 		scwAccessKey := os.Getenv("SCW_ACCESS_KEY")
 		if scwAccessKey == "" {
-			return nil, fmt.Errorf("SCW_ACCESS_KEY has to be set as an environment variable")
+			errList = append(errList, fmt.Errorf("SCW_ACCESS_KEY has to be set as an environment variable"))
 		}
-		env["SCW_ACCESS_KEY"] = scwAccessKey
-
 		scwSecretKey := os.Getenv("SCW_SECRET_KEY")
 		if scwSecretKey == "" {
-			return nil, fmt.Errorf("SCW_SECRET_KEY has to be set as an environment variable")
+			errList = append(errList, fmt.Errorf("SCW_SECRET_KEY has to be set as an environment variable"))
 		}
-		env["SCW_SECRET_KEY"] = scwSecretKey
-
 		scwProjectID := os.Getenv("SCW_DEFAULT_PROJECT_ID")
 		if scwProjectID == "" {
-			return nil, fmt.Errorf("SCW_DEFAULT_PROJECT_ID has to be set as an environment variable")
+			errList = append(errList, fmt.Errorf("SCW_DEFAULT_PROJECT_ID has to be set as an environment variable"))
 		}
+
+		// In theory all these variables will have been checked in NewScwCloud already
+		if len(errList) != 0 {
+			return nil, errors.NewAggregate(errList)
+		}
+
+		env["SCW_DEFAULT_REGION"] = string(region)
+		env["SCW_DEFAULT_ZONE"] = string(zone)
+		env["SCW_ACCESS_KEY"] = scwAccessKey
+		env["SCW_SECRET_KEY"] = scwSecretKey
 		env["SCW_DEFAULT_PROJECT_ID"] = scwProjectID
 	}
 

pkg/model/scalewaymodel/context.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scalewaymodel
 
 import (

pkg/model/scalewaymodel/instances.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scalewaymodel
 
 import (

pkg/model/scalewaymodel/sshkey.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scalewaymodel
 
 import (

upup/pkg/fi/cloudup/scaleway/OWNERS

@@ -1,3 +1,3 @@
 # See the OWNERS docs at https://go.k8s.io/owners
 labels:
-- area/provider/scaleway
+- area/provider/scaleway

upup/pkg/fi/cloudup/scaleway/api_target.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scaleway
 
 import "k8s.io/kops/upup/pkg/fi"

upup/pkg/fi/cloudup/scaleway/cloud.go

@@ -25,6 +25,7 @@ import (
 	"github.com/scaleway/scaleway-sdk-go/api/instance/v1"
 	"github.com/scaleway/scaleway-sdk-go/scw"
 	v1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/util/errors"
 	"k8s.io/klog/v2"
 	kopsv "k8s.io/kops"
 	"k8s.io/kops/dnsprovider/pkg/dnsprovider"
@@ -44,23 +45,23 @@ const (
 type ScwCloud interface {
 	fi.Cloud
 
+	ClusterName(tags []string) string
+	DNS() (dnsprovider.Interface, error)
+	ProviderID() kops.CloudProviderID
 	Region() string
 	Zone() string
-	ProviderID() kops.CloudProviderID
-	DNS() (dnsprovider.Interface, error)
-	ClusterName(tags []string) string
 
 	AccountService() *account.API
 	InstanceService() *instance.API
 
-	GetApiIngressStatus(cluster *kops.Cluster) ([]fi.ApiIngressStatus, error)
-	FindClusterStatus(cluster *kops.Cluster) (*kops.ClusterStatus, error)
-	GetCloudGroups(cluster *kops.Cluster, instancegroups []*kops.InstanceGroup, warnUnmatched bool, nodes []v1.Node) (map[string]*cloudinstances.CloudInstanceGroup, error)
 	DeleteGroup(group *cloudinstances.CloudInstanceGroup) error
-	FindVPCInfo(id string) (*fi.VPCInfo, error)
-	DetachInstance(instance *cloudinstances.CloudInstance) error
-	DeregisterInstance(instance *cloudinstances.CloudInstance) error
 	DeleteInstance(i *cloudinstances.CloudInstance) error
+	DeregisterInstance(instance *cloudinstances.CloudInstance) error
+	DetachInstance(instance *cloudinstances.CloudInstance) error
+	FindClusterStatus(cluster *kops.Cluster) (*kops.ClusterStatus, error)
+	FindVPCInfo(id string) (*fi.VPCInfo, error)
+	GetApiIngressStatus(cluster *kops.Cluster) ([]fi.ApiIngressStatus, error)
+	GetCloudGroups(cluster *kops.Cluster, instancegroups []*kops.InstanceGroup, warnUnmatched bool, nodes []v1.Node) (map[string]*cloudinstances.CloudInstanceGroup, error)
 
 	GetClusterServers(clusterName string, serverName *string) ([]*instance.Server, error)
 	GetClusterVolumes(clusterName string) ([]*instance.Volume, error)
@@ -86,31 +87,37 @@ type scwCloudImplementation struct {
 // NewScwCloud returns a Cloud with a Scaleway Client using the env vars SCW_ACCESS_KEY, SCW_SECRET_KEY,
 // SCW_DEFAULT_PROJECT_ID, SCW_DEFAULT_REGION and SCW_DEFAULT_ZONE
 func NewScwCloud(tags map[string]string) (ScwCloud, error) {
+	errList := []error(nil)
+
 	region, err := scw.ParseRegion(os.Getenv("SCW_DEFAULT_REGION"))
 	if err != nil {
-		return nil, fmt.Errorf("error parsing SCW_DEFAULT_REGION: %w", err)
+		errList = append(errList, fmt.Errorf("error parsing SCW_DEFAULT_REGION: %w", err))
 	}
 	zone, err := scw.ParseZone(os.Getenv("SCW_DEFAULT_ZONE"))
 	if err != nil {
-		return nil, fmt.Errorf("error parsing SCW_DEFAULT_ZONE: %w", err)
+		errList = append(errList, fmt.Errorf("error parsing SCW_DEFAULT_ZONE: %w", err))
 	}
 
 	// We make sure that the credentials env vars are defined
 	scwAccessKey := os.Getenv("SCW_ACCESS_KEY")
 	if scwAccessKey == "" {
-		return nil, fmt.Errorf("SCW_ACCESS_KEY has to be set as an environment variable")
+		errList = append(errList, fmt.Errorf("SCW_ACCESS_KEY has to be set as an environment variable"))
 	}
 	scwSecretKey := os.Getenv("SCW_SECRET_KEY")
 	if scwSecretKey == "" {
-		return nil, fmt.Errorf("SCW_SECRET_KEY has to be set as an environment variable")
+		errList = append(errList, fmt.Errorf("SCW_SECRET_KEY has to be set as an environment variable"))
 	}
 	scwProjectID := os.Getenv("SCW_DEFAULT_PROJECT_ID")
 	if scwProjectID == "" {
-		return nil, fmt.Errorf("SCW_DEFAULT_PROJECT_ID has to be set as an environment variable")
+		errList = append(errList, fmt.Errorf("SCW_DEFAULT_PROJECT_ID has to be set as an environment variable"))
+	}
+
+	if len(errList) != 0 {
+		return nil, errors.NewAggregate(errList)
 	}
 
 	scwClient, err := scw.NewClient(
-		scw.WithUserAgent("kubernetes-kops/"+kopsv.Version),
+		scw.WithUserAgent(KopsUserAgentPrefix+kopsv.Version),
 		scw.WithEnv(),
 	)
 	if err != nil {
@@ -127,14 +134,6 @@ func NewScwCloud(tags map[string]string) (ScwCloud, error) {
 	}, nil
 }
 
-func (s *scwCloudImplementation) Region() string {
-	return string(s.region)
-}
-
-func (s *scwCloudImplementation) Zone() string {
-	return string(s.zone)
-}
-
 func (s *scwCloudImplementation) ClusterName(tags []string) string {
 	for _, tag := range tags {
 		if strings.HasPrefix(tag, TagClusterName) {
@@ -144,13 +143,21 @@ func (s *scwCloudImplementation) ClusterName(tags []string) string {
 	return ""
 }
 
+func (s *scwCloudImplementation) DNS() (dnsprovider.Interface, error) {
+	klog.V(8).Infof("Scaleway DNS is not implemented yet")
+	return nil, fmt.Errorf("DNS is not implemented yet for Scaleway")
+}
+
 func (s *scwCloudImplementation) ProviderID() kops.CloudProviderID {
 	return kops.CloudProviderScaleway
 }
 
-func (s *scwCloudImplementation) DNS() (dnsprovider.Interface, error) {
+func (s *scwCloudImplementation) Region() string {
-	//TODO(Mia-Cross) implement me
+	return string(s.region)
-	panic("Scaleway doesn't have a DNS yet")
+}
+
+func (s *scwCloudImplementation) Zone() string {
+	return string(s.zone)
 }
 
 func (s *scwCloudImplementation) AccountService() *account.API {
@@ -161,10 +168,15 @@ func (s *scwCloudImplementation) InstanceService() *instance.API {
 	return s.instanceAPI
 }
 
-// FindVPCInfo is not implemented yet, it's only here to satisfy the fi.Cloud interface
+func (s *scwCloudImplementation) DeleteGroup(group *cloudinstances.CloudInstanceGroup) error {
-func (s *scwCloudImplementation) FindVPCInfo(id string) (*fi.VPCInfo, error) {
+	toDelete := append(group.NeedUpdate, group.Ready...)
-	klog.V(8).Info("FindVPCInfo is not implemented yet for Scaleway")
+	for _, cloudInstance := range toDelete {
-	return nil, fmt.Errorf("scaleway cloud provider does not support VPC at this time")
+		err := s.DeleteInstance(cloudInstance)
+		if err != nil {
+			return fmt.Errorf("error deleting group %q: %w", group.HumanName, err)
+		}
+	}
+	return nil
 }
 
 func (s *scwCloudImplementation) DeleteInstance(i *cloudinstances.CloudInstance) error {
@@ -189,24 +201,30 @@ func (s *scwCloudImplementation) DeleteInstance(i *cloudinstances.CloudInstance)
 }
 
 func (s *scwCloudImplementation) DeregisterInstance(i *cloudinstances.CloudInstance) error {
-	//TODO(Mia-Cross) implement me
+	klog.V(8).Infof("Scaleway DeregisterInstance is not implemented yet")
-	panic("implement me")
+	return fmt.Errorf("DeregisterInstance is not implemented yet for Scaleway")
-}
-
-func (s *scwCloudImplementation) DeleteGroup(group *cloudinstances.CloudInstanceGroup) error {
-	toDelete := append(group.NeedUpdate, group.Ready...)
-	for _, cloudInstance := range toDelete {
-		err := s.DeleteInstance(cloudInstance)
-		if err != nil {
-			return fmt.Errorf("error deleting group %q: %w", group.HumanName, err)
-		}
-	}
-	return nil
 }
 
 func (s *scwCloudImplementation) DetachInstance(i *cloudinstances.CloudInstance) error {
-	//TODO(Mia-Cross) implement me
+	klog.V(8).Infof("Scaleway DetachInstance is not implemented yet")
-	panic("implement me")
+	return fmt.Errorf("DetachInstance is not implemented yet for Scaleway")
+}
+
+// FindClusterStatus was used before etcd-manager to check the etcd cluster status and prevent unsupported changes.
+func (s *scwCloudImplementation) FindClusterStatus(cluster *kops.Cluster) (*kops.ClusterStatus, error) {
+	klog.V(8).Info("Scaleway FindClusterStatus is not implemented")
+	return nil, nil
+}
+
+// FindVPCInfo is not implemented yet, it's only here to satisfy the fi.Cloud interface
+func (s *scwCloudImplementation) FindVPCInfo(id string) (*fi.VPCInfo, error) {
+	klog.V(8).Info("Scaleway doesn't have a VPC yet so FindVPCInfo is not implemented")
+	return nil, fmt.Errorf("FindVPCInfo is not implemented yet for Scaleway")
+}
+
+func (s *scwCloudImplementation) GetApiIngressStatus(cluster *kops.Cluster) ([]fi.ApiIngressStatus, error) {
+	klog.V(8).Info("Scaleway doesn't have load-balancers yet so GetApiIngressStatus is not implemented")
+	return nil, fmt.Errorf("GetApiIngressStatus is not implemented yet for Scaleway")
 }
 
 func (s *scwCloudImplementation) GetCloudGroups(cluster *kops.Cluster, instancegroups []*kops.InstanceGroup, warnUnmatched bool, nodes []v1.Node) (map[string]*cloudinstances.CloudInstanceGroup, error) {
@@ -219,24 +237,18 @@ func (s *scwCloudImplementation) GetCloudGroups(cluster *kops.Cluster, instanceg
 		return nil, fmt.Errorf("failed to find server groups: %w", err)
 	}
 
-	for igName, serverGroup := range serverGroups {
+	for _, ig := range instancegroups {
-		var instanceGroup *kops.InstanceGroup
+		serverGroup, ok := serverGroups[ig.Name]
-		for _, ig := range instancegroups {
+		if !ok {
-			if igName == ig.Name {
-				instanceGroup = ig
-				break
-			}
-		}
-		if instanceGroup == nil {
 			if warnUnmatched {
-				klog.Warningf("Server group %q has no corresponding instance group", igName)
+				klog.Warningf("Server group %q has no corresponding instance group", ig.Name)
 			}
 			continue
 		}
 
-		groups[instanceGroup.Name], err = buildCloudGroup(instanceGroup, serverGroup, nodeMap)
+		groups[ig.Name], err = buildCloudGroup(ig, serverGroup, nodeMap)
 		if err != nil {
-			return nil, fmt.Errorf("failed to build cloud group for instance group %q: %w", instanceGroup.Name, err)
+			return nil, fmt.Errorf("failed to build cloud group for instance group %q: %w", ig.Name, err)
 		}
 	}
 
@@ -295,16 +307,6 @@ func buildCloudGroup(ig *kops.InstanceGroup, sg []*instance.Server, nodeMap map[
 	return cloudInstanceGroup, nil
 }
 
-func (s *scwCloudImplementation) FindClusterStatus(cluster *kops.Cluster) (*kops.ClusterStatus, error) {
-	klog.V(8).Info("FindClusterStatus is not implemented yet for Scaleway")
-	return nil, nil
-}
-
-func (s *scwCloudImplementation) GetApiIngressStatus(cluster *kops.Cluster) ([]fi.ApiIngressStatus, error) {
-	//TODO(Mia-Cross) implement me
-	panic("implement me")
-}
-
 func (s *scwCloudImplementation) GetClusterServers(clusterName string, serverName *string) ([]*instance.Server, error) {
 	request := &instance.ListServersRequest{
 		Zone: s.zone,
@@ -372,14 +374,12 @@ func (s *scwCloudImplementation) DeleteServer(server *instance.Server) error {
 	if err != nil {
 		return fmt.Errorf("delete server %s: error deleting instance: %w", server.ID, err)
 	}
-	for {
+	_, err = s.instanceAPI.WaitForServer(&instance.WaitForServerRequest{
-		_, err := s.instanceAPI.GetServer(&instance.GetServerRequest{
+		ServerID: server.ID,
-			Zone:     s.zone,
+		Zone:     s.zone,
-			ServerID: server.ID,
+	})
-		})
+	if !is404Error(err) {
-		if is404Error(err) {
+		return fmt.Errorf("delete server %s: error waiting for instance after deletion: %w", server.ID, err)
-			break
-		}
 	}
 
 	// We delete the volumes that were attached to the server (including etcd volumes)
@@ -404,5 +404,14 @@ func (s *scwCloudImplementation) DeleteVolume(volume *instance.Volume) error {
 	if err != nil {
 		return fmt.Errorf("failed to delete volume %s: %w", volume.ID, err)
 	}
+
+	_, err = s.instanceAPI.WaitForVolume(&instance.WaitForVolumeRequest{
+		VolumeID: volume.ID,
+		Zone:     s.zone,
+	})
+	if !is404Error(err) {
+		return fmt.Errorf("delete server %s: error waiting for volume after deletion: %w", volume.ID, err)
+	}
+
 	return nil
 }

upup/pkg/fi/cloudup/scaleway/utils.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scaleway
 
 import (

upup/pkg/fi/cloudup/scalewaytasks/OWNERS

@@ -1,3 +1,3 @@
 # See the OWNERS docs at https://go.k8s.io/owners
 labels:
-- area/provider/scaleway
+- area/provider/scaleway

upup/pkg/fi/cloudup/scalewaytasks/instance.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scalewaytasks
 
 import (
@@ -59,59 +75,37 @@ func (s *Instance) Run(c *fi.Context) error {
 	return fi.DefaultDeltaRunMethod(s, c)
 }
 
-func (_ *Instance) RenderScw(c *fi.Context, a, e, changes *Instance) error {
+func (_ *Instance) RenderScw(c *fi.Context, actual, expected, changes *Instance) error {
 	cloud := c.Cloud.(scaleway.ScwCloud)
 	instanceService := cloud.InstanceService()
-	zone := scw.Zone(fi.StringValue(e.Zone))
+	zone := scw.Zone(fi.StringValue(expected.Zone))
 
-	userData, err := fi.ResourceAsBytes(*e.UserData)
+	userData, err := fi.ResourceAsBytes(*expected.UserData)
 	if err != nil {
 		return fmt.Errorf("error rendering instances: %w", err)
 	}
 
-	var newInstanceCount int
+	newInstanceCount := expected.Count
-	if a == nil {
+	if actual != nil {
-		newInstanceCount = e.Count
+		if expected.Count == actual.Count {
-	} else {
-		expectedCount := e.Count
-		actualCount := a.Count
-
-		if expectedCount == actualCount {
 			return nil
 		}
-
+		newInstanceCount = expected.Count - actual.Count
-		if actualCount > expectedCount {
-			igInstances, err := cloud.GetClusterServers(cloud.ClusterName(a.Tags), a.Name)
-			if err != nil {
-				return fmt.Errorf("error deleting instance: %w", err)
-			}
-			for _, igInstance := range igInstances {
-				err = cloud.DeleteServer(igInstance)
-				if err != nil {
-					return fmt.Errorf("error deleting instance of group %s: %w", igInstance.Name, err)
-				}
-				actualCount--
-				if expectedCount == actualCount {
-					break
-				}
-			}
-		}
-
-		newInstanceCount = expectedCount - actualCount
 	}
 
+	// If newInstanceCount > 0, we need to create new instances for this group
 	for i := 0; i < newInstanceCount; i++ {
 
 		// We create the instance
 		srv, err := instanceService.CreateServer(&instance.CreateServerRequest{
 			Zone:           zone,
-			Name:           fi.StringValue(e.Name),
+			Name:           fi.StringValue(expected.Name),
-			CommercialType: fi.StringValue(e.CommercialType),
+			CommercialType: fi.StringValue(expected.CommercialType),
-			Image:          fi.StringValue(e.Image),
+			Image:          fi.StringValue(expected.Image),
-			Tags:           e.Tags,
+			Tags:           expected.Tags,
 		})
 		if err != nil {
-			return fmt.Errorf("error creating instance of group %q: %w", fi.StringValue(e.Name), err)
+			return fmt.Errorf("error creating instance of group %q: %w", fi.StringValue(expected.Name), err)
 		}
 
 		// We wait for the instance to be ready
@@ -120,7 +114,7 @@ func (_ *Instance) RenderScw(c *fi.Context, a, e, changes *Instance) error {
 			Zone:     zone,
 		})
 		if err != nil {
-			return fmt.Errorf("error waiting for instance %s of group %q: %w", srv.Server.ID, fi.StringValue(e.Name), err)
+			return fmt.Errorf("error waiting for instance %s of group %q: %w", srv.Server.ID, fi.StringValue(expected.Name), err)
 		}
 
 		// We load the cloud-init script in the instance user data
@@ -131,7 +125,7 @@ func (_ *Instance) RenderScw(c *fi.Context, a, e, changes *Instance) error {
 			Content:  bytes.NewBuffer(userData),
 		})
 		if err != nil {
-			return fmt.Errorf("error setting 'cloud-init' in user-data for instance %s of group %q: %w", srv.Server.ID, fi.StringValue(e.Name), err)
+			return fmt.Errorf("error setting 'cloud-init' in user-data for instance %s of group %q: %w", srv.Server.ID, fi.StringValue(expected.Name), err)
 		}
 
 		// We start the instance
@@ -141,7 +135,7 @@ func (_ *Instance) RenderScw(c *fi.Context, a, e, changes *Instance) error {
 			Action:   instance.ServerActionPoweron,
 		})
 		if err != nil {
-			return fmt.Errorf("error powering on instance %s of group %q: %w", srv.Server.ID, fi.StringValue(e.Name), err)
+			return fmt.Errorf("error powering on instance %s of group %q: %w", srv.Server.ID, fi.StringValue(expected.Name), err)
 		}
 
 		// We wait for the instance to be ready
@@ -150,15 +144,31 @@ func (_ *Instance) RenderScw(c *fi.Context, a, e, changes *Instance) error {
 			Zone:     zone,
 		})
 		if err != nil {
-			return fmt.Errorf("error waiting for instance %s of group %q: %w", srv.Server.ID, fi.StringValue(e.Name), err)
+			return fmt.Errorf("error waiting for instance %s of group %q: %w", srv.Server.ID, fi.StringValue(expected.Name), err)
+		}
+	}
+
+	// If newInstanceCount < 0, we need to delete instances of this group
+	for i := 0; i > expected.Count; i-- {
+
+		igInstances, err := cloud.GetClusterServers(cloud.ClusterName(actual.Tags), actual.Name)
+		if err != nil {
+			return fmt.Errorf("error deleting instance: %w", err)
+		}
+
+		for _, igInstance := range igInstances {
+			err = cloud.DeleteServer(igInstance)
+			if err != nil {
+				return fmt.Errorf("error deleting instance of group %s: %w", igInstance.Name, err)
+			}
 		}
 	}
 
 	return nil
 }
 
-func (_ *Instance) CheckChanges(a, e, changes *Instance) error {
+func (_ *Instance) CheckChanges(actual, expected, changes *Instance) error {
-	if a != nil {
+	if actual != nil {
 		if changes.Name != nil {
 			return fi.CannotChangeField("Name")
 		}
@@ -172,16 +182,16 @@ func (_ *Instance) CheckChanges(a, e, changes *Instance) error {
 			return fi.CannotChangeField("Image")
 		}
 	} else {
-		if e.Name == nil {
+		if expected.Name == nil {
 			return fi.RequiredField("Name")
 		}
-		if e.Zone == nil {
+		if expected.Zone == nil {
 			return fi.RequiredField("Zone")
 		}
-		if e.CommercialType == nil {
+		if expected.CommercialType == nil {
 			return fi.RequiredField("CommercialType")
 		}
-		if e.Image == nil {
+		if expected.Image == nil {
 			return fi.RequiredField("Image")
 		}
 	}

upup/pkg/fi/cloudup/scalewaytasks/instance_fitask.go

@@ -0,0 +1,52 @@
+//go:build !ignore_autogenerated
+// +build !ignore_autogenerated
+
+/*
+Copyright 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.
+*/
+
+// Code generated by fitask. DO NOT EDIT.
+
+package scalewaytasks
+
+import (
+	"k8s.io/kops/upup/pkg/fi"
+)
+
+// Instance
+
+var _ fi.HasLifecycle = &Instance{}
+
+// GetLifecycle returns the Lifecycle of the object, implementing fi.HasLifecycle
+func (o *Instance) GetLifecycle() fi.Lifecycle {
+	return o.Lifecycle
+}
+
+// SetLifecycle sets the Lifecycle of the object, implementing fi.SetLifecycle
+func (o *Instance) SetLifecycle(lifecycle fi.Lifecycle) {
+	o.Lifecycle = lifecycle
+}
+
+var _ fi.HasName = &Instance{}
+
+// GetName returns the Name of the object, implementing fi.HasName
+func (o *Instance) GetName() *string {
+	return o.Name
+}
+
+// String is the stringer function for the task, producing readable output using fi.TaskAsString
+func (o *Instance) String() string {
+	return fi.TaskAsString(o)
+}

upup/pkg/fi/cloudup/scalewaytasks/sshkey.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2022 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 scalewaytasks
 
 import (
@@ -46,25 +62,25 @@ func (s *SSHKey) Find(c *fi.Context) (*SSHKey, error) {
 
 	klog.V(2).Infof("found matching SSH key named %q", *s.Name)
 	k := keysResp.SSHKeys[0]
-	actual := &SSHKey{
+	sshKey := &SSHKey{
 		ID:                 fi.String(k.ID),
 		Name:               fi.String(k.Name),
 		KeyPairFingerPrint: fi.String(k.Fingerprint),
 	}
 
 	// Avoid spurious changes
-	if strings.Contains(fi.StringValue(actual.KeyPairFingerPrint), fi.StringValue(s.KeyPairFingerPrint)) {
+	if strings.Contains(fi.StringValue(sshKey.KeyPairFingerPrint), fi.StringValue(s.KeyPairFingerPrint)) {
 		klog.V(2).Infof("SSH key fingerprints match; assuming public keys match")
-		actual.PublicKey = s.PublicKey
+		sshKey.PublicKey = s.PublicKey
-		actual.KeyPairFingerPrint = s.KeyPairFingerPrint
+		sshKey.KeyPairFingerPrint = s.KeyPairFingerPrint
 	} else {
-		klog.V(2).Infof("Computed SSH key fingerprint mismatch: %q %q", fi.StringValue(s.KeyPairFingerPrint), fi.StringValue(actual.KeyPairFingerPrint))
+		klog.V(2).Infof("Computed SSH key fingerprint mismatch: %q %q", fi.StringValue(s.KeyPairFingerPrint), fi.StringValue(sshKey.KeyPairFingerPrint))
 	}
 
 	// Ignore "system" fields
-	actual.Lifecycle = s.Lifecycle
+	sshKey.Lifecycle = s.Lifecycle
 
-	return actual, nil
+	return sshKey, nil
 }
 
 func (s *SSHKey) Run(c *fi.Context) error {
@@ -84,8 +100,8 @@ func (s *SSHKey) Run(c *fi.Context) error {
 	return fi.DefaultDeltaRunMethod(s, c)
 }
 
-func (s *SSHKey) CheckChanges(a, e, changes *SSHKey) error {
+func (s *SSHKey) CheckChanges(actual, expected, changes *SSHKey) error {
-	if a != nil {
+	if actual != nil {
 		if changes.Name != nil {
 			return fi.CannotChangeField("Name")
 		}
@@ -93,12 +109,12 @@ func (s *SSHKey) CheckChanges(a, e, changes *SSHKey) error {
 	return nil
 }
 
-func (*SSHKey) RenderScw(c *fi.Context, a, e, changes *SSHKey) error {
+func (*SSHKey) RenderScw(c *fi.Context, actual, expected, changes *SSHKey) error {
 	cloud := c.Cloud.(scaleway.ScwCloud)
 
-	if a == nil {
+	if actual == nil {
 
-		name := fi.StringValue(e.Name)
+		name := fi.StringValue(expected.Name)
 		if name == "" {
 			return fi.RequiredField("Name")
 		}
@@ -107,8 +123,8 @@ func (*SSHKey) RenderScw(c *fi.Context, a, e, changes *SSHKey) error {
 		keyArgs := &account.CreateSSHKeyRequest{
 			Name: name,
 		}
-		if e.PublicKey != nil {
+		if expected.PublicKey != nil {
-			d, err := fi.ResourceAsString(*e.PublicKey)
+			d, err := fi.ResourceAsString(*expected.PublicKey)
 			if err != nil {
 				return fmt.Errorf("error rendering SSH public key: %w", err)
 			}
@@ -119,14 +135,14 @@ func (*SSHKey) RenderScw(c *fi.Context, a, e, changes *SSHKey) error {
 		if err != nil {
 			return fmt.Errorf("error creating SSH keypair: %w", err)
 		}
-		e.KeyPairFingerPrint = fi.String(key.Fingerprint)
+		expected.KeyPairFingerPrint = fi.String(key.Fingerprint)
 		klog.V(2).Infof("Created a new SSH keypair, id=%q fingerprint=%q", key.ID, key.Fingerprint)
 
 		return nil
 	}
 
-	e.KeyPairFingerPrint = a.KeyPairFingerPrint
+	expected.KeyPairFingerPrint = actual.KeyPairFingerPrint
-	klog.V(2).Infof("Using an existing SSH keypair, fingerprint=%q", fi.StringValue(e.KeyPairFingerPrint))
+	klog.V(2).Infof("Using an existing SSH keypair, fingerprint=%q", fi.StringValue(expected.KeyPairFingerPrint))
 
 	return nil
 }

upup/pkg/fi/cloudup/scalewaytasks/sshkey_fitask.go

@@ -0,0 +1,52 @@
+//go:build !ignore_autogenerated
+// +build !ignore_autogenerated
+
+/*
+Copyright 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.
+*/
+
+// Code generated by fitask. DO NOT EDIT.
+
+package scalewaytasks
+
+import (
+	"k8s.io/kops/upup/pkg/fi"
+)
+
+// SSHKey
+
+var _ fi.HasLifecycle = &SSHKey{}
+
+// GetLifecycle returns the Lifecycle of the object, implementing fi.HasLifecycle
+func (o *SSHKey) GetLifecycle() fi.Lifecycle {
+	return o.Lifecycle
+}
+
+// SetLifecycle sets the Lifecycle of the object, implementing fi.SetLifecycle
+func (o *SSHKey) SetLifecycle(lifecycle fi.Lifecycle) {
+	o.Lifecycle = lifecycle
+}
+
+var _ fi.HasName = &SSHKey{}
+
+// GetName returns the Name of the object, implementing fi.HasName
+func (o *SSHKey) GetName() *string {
+	return o.Name
+}
+
+// String is the stringer function for the task, producing readable output using fi.TaskAsString
+func (o *SSHKey) String() string {
+	return fi.TaskAsString(o)
+}