Add support for using an existing network for Hetzner

pkg/apis/kops/validation/legacy.go

@@ -92,6 +92,7 @@ func ValidateCluster(c *kops.Cluster, strict bool) field.ErrorList {
 			allErrs = append(allErrs, field.Forbidden(fieldSpec.Child("hetzner"), "only one cloudProvider option permitted"))
 		}
 		optionTaken = true
+		requiresNetworkCIDR = false
 		requiresSubnets = false
 		requiresSubnetCIDR = false
 	}

pkg/model/hetznermodel/network.go

@@ -34,16 +34,21 @@ func (b *NetworkModelBuilder) Build(c *fi.ModelBuilderContext) error {
 	network := &hetznertasks.Network{
 		Name:      fi.String(b.ClusterName()),
 		Lifecycle: b.Lifecycle,
-		Region:    b.Region,
-		IPRange:   b.Cluster.Spec.NetworkCIDR,
-		// TODO(hakman): Add support for additional subnets?
-		Subnets: []string{
-			b.Cluster.Spec.NetworkCIDR,
-		},
-		Labels: map[string]string{
-			hetzner.TagKubernetesClusterName: b.ClusterName(),
-		},
 	}
+
+	if b.Cluster.Spec.NetworkID == "" {
+		network.IPRange = b.Cluster.Spec.NetworkCIDR
+		network.Region = b.Region
+		network.Subnets = []string{
+			b.Cluster.Spec.NetworkCIDR,
+		}
+		network.Labels = map[string]string{
+			hetzner.TagKubernetesClusterName: b.ClusterName(),
+		}
+	} else {
+		network.ID = fi.String(b.Cluster.Spec.NetworkID)
+	}
+
 	c.AddTask(network)
 
 	return nil

upup/models/cloudup/resources/addons/hcloud-cloud-controller.addons.k8s.io/k8s-1.22.yaml.template

@@ -6,8 +6,8 @@ metadata:
   name: hcloud
   namespace: kube-system
 stringData:
-  token: {{ HCLOUD_TOKEN }}
-  network: {{ ClusterName }}
+  token: "{{ HCLOUD_TOKEN }}"
+  network: "{{ HCLOUD_NETWORK }}"
 ---
 apiVersion: v1
 kind: ServiceAccount

upup/pkg/fi/cloudup/hetznertasks/loadbalancer.go

@@ -199,6 +199,11 @@ func (_ *LoadBalancer) RenderHetzner(t *hetzner.HetznerAPITarget, a, e, changes
 			return fmt.Errorf("failed to find network for loadbalancer %q", fi.StringValue(e.Name))
 		}
 
+		networkID, err := strconv.Atoi(fi.StringValue(e.Network.ID))
+		if err != nil {
+			return fmt.Errorf("failed to convert network ID %q to int: %w", fi.StringValue(e.Network.ID), err)
+		}
+
 		opts := hcloud.LoadBalancerCreateOpts{
 			Name: fi.StringValue(e.Name),
 			LoadBalancerType: &hcloud.LoadBalancerType{
@@ -221,7 +226,7 @@ func (_ *LoadBalancer) RenderHetzner(t *hetzner.HetznerAPITarget, a, e, changes
 				},
 			},
 			Network: &hcloud.Network{
-				ID: fi.IntValue(e.Network.ID),
+				ID: networkID,
 			},
 		}
 

upup/pkg/fi/cloudup/hetznertasks/network.go

@@ -18,6 +18,7 @@ package hetznertasks
 
 import (
 	"context"
+	"fmt"
 	"net"
 	"strconv"
 	"time"
@@ -34,7 +35,7 @@ type Network struct {
 	Name      *string
 	Lifecycle fi.Lifecycle
 
-	ID      *int
+	ID      *string
 	Region  string
 	IPRange string
 	Subnets []string
@@ -45,41 +46,53 @@ type Network struct {
 var _ fi.CompareWithID = &Network{}
 
 func (v *Network) CompareWithID() *string {
-	return fi.String(strconv.Itoa(fi.IntValue(v.ID)))
+	return v.ID
 }
 
 func (v *Network) Find(c *fi.Context) (*Network, error) {
 	cloud := c.Cloud.(hetzner.HetznerCloud)
 	client := cloud.NetworkClient()
 
-	// TODO(hakman): Find using label selector
-	networks, err := client.All(context.TODO())
+	idOrName := fi.StringValue(v.Name)
+	if v.ID != nil {
+		idOrName = fi.StringValue(v.ID)
+	}
+
+	network, _, err := client.Get(context.TODO(), idOrName)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("failed to find network %q: %w", idOrName, err)
 	}
-
-	for _, network := range networks {
-		if network.Name == fi.StringValue(v.Name) {
-			matches := &Network{
-				Name:      fi.String(network.Name),
-				Lifecycle: v.Lifecycle,
-				ID:        fi.Int(network.ID),
-				IPRange:   network.IPRange.String(),
-				Labels:    network.Labels,
-			}
-			matches.Region = v.Region
-			for _, subnet := range network.Subnets {
-				if subnet.IPRange != nil {
-					matches.Region = string(subnet.NetworkZone)
-					matches.Subnets = append(matches.Subnets, subnet.IPRange.String())
-				}
-			}
-			v.ID = matches.ID
-			return matches, nil
+	if network == nil {
+		if v.ID != nil {
+			return nil, fmt.Errorf("failed to find network %q", idOrName)
 		}
+		return nil, nil
 	}
 
-	return nil, nil
+	matches := &Network{
+		Name:      v.Name,
+		Lifecycle: v.Lifecycle,
+		ID:        fi.String(strconv.Itoa(network.ID)),
+	}
+
+	if v.ID == nil {
+		matches.IPRange = network.IPRange.String()
+		matches.Labels = network.Labels
+		matches.Region = v.Region
+		for _, subnet := range network.Subnets {
+			if subnet.IPRange != nil {
+				matches.Region = string(subnet.NetworkZone)
+				matches.Subnets = append(matches.Subnets, subnet.IPRange.String())
+			}
+		}
+		// Make sure the ID is set (used by other tasks)
+		v.ID = matches.ID
+	} else {
+		// Make sure the ID is numerical
+		v.ID = matches.ID
+	}
+
+	return matches, nil
 }
 
 func (v *Network) Run(c *fi.Context) error {
@@ -138,7 +151,7 @@ func (_ *Network) RenderHetzner(t *hetzner.HetznerAPITarget, a, e, changes *Netw
 		if err != nil {
 			return err
 		}
-		e.ID = fi.Int(network.ID)
+		e.ID = fi.String(strconv.Itoa(network.ID))
 
 	} else {
 		var err error

upup/pkg/fi/cloudup/hetznertasks/servergroup.go

@@ -22,6 +22,7 @@ import (
 	"encoding/base64"
 	"fmt"
 	"math/rand"
+	"strconv"
 	"strings"
 
 	"github.com/hetznercloud/hcloud-go/hcloud"
@@ -205,6 +206,11 @@ func (_ *ServerGroup) RenderHetzner(t *hetzner.HetznerAPITarget, a, e, changes *
 	}
 	userDataHash := safeBytesHash(userDataBytes)
 
+	networkID, err := strconv.Atoi(fi.StringValue(e.Network.ID))
+	if err != nil {
+		return fmt.Errorf("failed to convert network ID %q to int: %w", fi.StringValue(e.Network.ID), err)
+	}
+
 	for i := 1; i <= expectedCount-actualCount; i++ {
 		// Append a random/unique ID to the node name
 		name := fmt.Sprintf("%s-%x", fi.StringValue(e.Name), rand.Int63())
@@ -214,7 +220,7 @@ func (_ *ServerGroup) RenderHetzner(t *hetzner.HetznerAPITarget, a, e, changes *
 			StartAfterCreate: fi.Bool(true),
 			Networks: []*hcloud.Network{
 				{
-					ID: fi.IntValue(e.Network.ID),
+					ID: networkID,
 				},
 			},
 			Location: &hcloud.Location{

upup/pkg/fi/cloudup/template_functions.go

@@ -173,6 +173,12 @@ func (tf *TemplateFunctions) AddTo(dest template.FuncMap, secretStore fi.SecretS
 	dest["HCLOUD_TOKEN"] = func() string {
 		return os.Getenv("HCLOUD_TOKEN")
 	}
+	dest["HCLOUD_NETWORK"] = func() string {
+		if cluster.Spec.NetworkID != "" {
+			return cluster.Spec.NetworkID
+		}
+		return cluster.Name
+	}
 
 	if featureflag.Spotinst.Enabled() {
 		if creds, err := spotinst.LoadCredentials(); err == nil {