Add ability to set DockerClusterSpec load balancer

We need the ability to set the repository and tag of the load balancer
to use. This adds a field to the DockerClusterSpec in the v1alpha4 API
to enable this.

Signed-off-by: Sean McGinnis <[email protected]>

test/infrastructure/docker/api/v1alpha3/conversion.go

@@ -0,0 +1,69 @@
+/*
+Copyright 2021 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 v1alpha3
+
+import (
+	apiconversion "k8s.io/apimachinery/pkg/conversion"
+	"sigs.k8s.io/cluster-api/test/infrastructure/docker/api/v1alpha4"
+	utilconversion "sigs.k8s.io/cluster-api/util/conversion"
+	"sigs.k8s.io/controller-runtime/pkg/conversion"
+)
+
+func (src *DockerCluster) ConvertTo(dstRaw conversion.Hub) error {
+	dst := dstRaw.(*v1alpha4.DockerCluster)
+
+	if err := Convert_v1alpha3_DockerCluster_To_v1alpha4_DockerCluster(src, dst, nil); err != nil {
+		return err
+	}
+
+	// Manually restore data.
+	restored := &v1alpha4.DockerCluster{}
+	if ok, err := utilconversion.UnmarshalData(src, restored); err != nil || !ok {
+		return err
+	}
+
+	if restored.Spec.LoadBalancer.ImageRepository != "" {
+		dst.Spec.LoadBalancer.ImageRepository = restored.Spec.LoadBalancer.ImageRepository
+	}
+
+	if restored.Spec.LoadBalancer.ImageTag != "" {
+		dst.Spec.LoadBalancer.ImageTag = restored.Spec.LoadBalancer.ImageTag
+	}
+
+	return nil
+}
+
+func (dst *DockerCluster) ConvertFrom(srcRaw conversion.Hub) error {
+	src := srcRaw.(*v1alpha4.DockerCluster)
+
+	if err := Convert_v1alpha4_DockerCluster_To_v1alpha3_DockerCluster(src, dst, nil); err != nil {
+		return err
+	}
+
+	// Preserve Hub data on down-conversion except for metadata
+	if err := utilconversion.MarshalData(src, dst); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Convert_v1alpha4_DockerClusterSpec_To_v1alpha3_DockerClusterSpec is an autogenerated conversion function.
+func Convert_v1alpha4_DockerClusterSpec_To_v1alpha3_DockerClusterSpec(in *v1alpha4.DockerClusterSpec, out *DockerClusterSpec, s apiconversion.Scope) error {
+	// DockerClusterSpec.LoadBalancer was added in v1alpha4, so automatic conversion is not possible
+	return autoConvert_v1alpha4_DockerClusterSpec_To_v1alpha3_DockerClusterSpec(in, out, s)
+}

test/infrastructure/docker/api/v1alpha4/conversion.go

@@ -0,0 +1,20 @@
+/*
+Copyright 2021 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 v1alpha4
+
+func (*DockerCluster) Hub()     {}
+func (*DockerClusterList) Hub() {}

test/infrastructure/docker/api/v1alpha4/dockercluster_types.go

@@ -42,6 +42,30 @@ type DockerClusterSpec struct {
 	// controllers to do what they will with the defined failure domains.
 	// +optional
 	FailureDomains clusterv1.FailureDomains `json:"failureDomains,omitempty"`
+
+	// LoadBalancer allows defining configurations for the cluster load balancer.
+	// +optional
+	LoadBalancer DockerLoadBalancer `json:"loadBalancer,omitempty"`
+}
+
+// DockerLoadBalancer allows defining configurations for the cluster load balancer.
+type DockerLoadBalancer struct {
+	// ImageMeta allows customizing the image used for the cluster load balancer.
+	ImageMeta `json:",inline"`
+}
+
+// ImageMeta allows customizing the image used for components that are not
+// originated from the Kubernetes/Kubernetes release process.
+type ImageMeta struct {
+	// ImageRepository sets the container registry to pull the haproxy image from.
+	// if not set, "kindest" will be used instead.
+	// +optional
+	ImageRepository string `json:"imageRepository,omitempty"`
+
+	// ImageTag allows to specify a tag for the haproxy image.
+	// if not set, "v20210715-a6da3463" will be used instead.
+	// +optional
+	ImageTag string `json:"imageTag,omitempty"`
 }
 
 // DockerClusterStatus defines the observed state of DockerCluster.

test/infrastructure/docker/config/crd/bases/infrastructure.cluster.x-k8s.io_dockerclusters.yaml

@@ -213,6 +213,19 @@ spec:
                   will simply copy these into the Status and allow the Cluster API
                   controllers to do what they will with the defined failure domains.
                 type: object
+              loadBalancer:
+                description: LoadBalancer allows defining configurations for the cluster
+                  load balancer.
+                properties:
+                  imageRepository:
+                    description: ImageRepository sets the container registry to pull
+                      the haproxy image from. if not set, "kindest" will be used instead.
+                    type: string
+                  imageTag:
+                    description: ImageTag allows to specify a tag for the haproxy
+                      image. if not set, "v20210715-a6da3463" will be used instead.
+                    type: string
+                type: object
             type: object
           status:
             description: DockerClusterStatus defines the observed state of DockerCluster.

test/infrastructure/docker/controllers/dockercluster_controller.go

@@ -73,7 +73,7 @@ func (r *DockerClusterReconciler) Reconcile(ctx context.Context, req ctrl.Reques
 	log = log.WithValues("cluster", cluster.Name)
 
 	// Create a helper for managing a docker container hosting the loadbalancer.
-	externalLoadBalancer, err := docker.NewLoadBalancer(cluster)
+	externalLoadBalancer, err := docker.NewLoadBalancer(cluster, dockerCluster)
 	if err != nil {
 		return ctrl.Result{}, errors.Wrapf(err, "failed to create helper for managing the externalLoadBalancer")
 	}

test/infrastructure/docker/controllers/dockermachine_controller.go

@@ -147,7 +147,7 @@ func (r *DockerMachineReconciler) Reconcile(ctx context.Context, req ctrl.Reques
 	// NB. the machine controller has to manage the cluster load balancer because the current implementation of the
 	// docker load balancer does not support auto-discovery of control plane nodes, so CAPD should take care of
 	// updating the cluster load balancer configuration when control plane machines are added/removed
-	externalLoadBalancer, err := docker.NewLoadBalancer(cluster)
+	externalLoadBalancer, err := docker.NewLoadBalancer(cluster, dockerCluster)
 	if err != nil {
 		return ctrl.Result{}, errors.Wrapf(err, "failed to create helper for managing the externalLoadBalancer")
 	}

test/infrastructure/docker/docker/loadbalancer.go

@@ -24,6 +24,7 @@ import (
 	"github.com/pkg/errors"
 	clusterv1 "sigs.k8s.io/cluster-api/api/v1alpha4"
 	"sigs.k8s.io/cluster-api/test/infrastructure/container"
+	"sigs.k8s.io/cluster-api/test/infrastructure/docker/api/v1alpha4"
 	"sigs.k8s.io/cluster-api/test/infrastructure/docker/docker/types"
 	"sigs.k8s.io/cluster-api/test/infrastructure/docker/third_party/forked/loadbalancer"
 	ctrl "sigs.k8s.io/controller-runtime"
@@ -37,13 +38,14 @@ type lbCreator interface {
 // LoadBalancer manages the load balancer for a specific docker cluster.
 type LoadBalancer struct {
 	name      string
+	image     string
 	container *types.Node
 	ipFamily  clusterv1.ClusterIPFamily
 	lbCreator lbCreator
 }
 
 // NewLoadBalancer returns a new helper for managing a docker loadbalancer with a given name.
-func NewLoadBalancer(cluster *clusterv1.Cluster) (*LoadBalancer, error) {
+func NewLoadBalancer(cluster *clusterv1.Cluster, dockerCluster *v1alpha4.DockerCluster) (*LoadBalancer, error) {
 	if cluster.Name == "" {
 		return nil, errors.New("create load balancer: cluster name is empty")
 	}
@@ -65,14 +67,37 @@ func NewLoadBalancer(cluster *clusterv1.Cluster) (*LoadBalancer, error) {
 		return nil, fmt.Errorf("create load balancer: %s", err)
 	}
 
+	image := getLoadBalancerImage(dockerCluster)
+
 	return &LoadBalancer{
 		name:      cluster.Name,
+		image:     image,
 		container: container,
 		ipFamily:  ipFamily,
 		lbCreator: &Manager{},
 	}, nil
 }
 
+// getLoadBalancerImage will return the image (e.g. "kindest/haproxy:2.1.1-alpine") to use for
+// the load balancer.
+func getLoadBalancerImage(dockerCluster *v1alpha4.DockerCluster) string {
+	// Check if a non-default image was provided
+	image := loadbalancer.Image
+	imageRepo := loadbalancer.DefaultImageRepository
+	imageTag := loadbalancer.DefaultImageTag
+
+	if dockerCluster != nil {
+		if dockerCluster.Spec.LoadBalancer.ImageRepository != "" {
+			imageRepo = dockerCluster.Spec.LoadBalancer.ImageRepository
+		}
+		if dockerCluster.Spec.LoadBalancer.ImageTag != "" {
+			imageTag = dockerCluster.Spec.LoadBalancer.ImageTag
+		}
+	}
+
+	return fmt.Sprintf("%s/%s:%s", imageRepo, image, imageTag)
+}
+
 // ContainerName is the name of the docker container with the load balancer.
 func (s *LoadBalancer) containerName() string {
 	return fmt.Sprintf("%s-lb", s.name)
@@ -94,7 +119,7 @@ func (s *LoadBalancer) Create(ctx context.Context) error {
 		s.container, err = s.lbCreator.CreateExternalLoadBalancerNode(
 			ctx,
 			s.containerName(),
-			loadbalancer.Image,
+			s.image,
 			s.name,
 			listenAddr,
 			0,

test/infrastructure/docker/third_party/forked/loadbalancer/const.go

@@ -16,8 +16,14 @@ limitations under the License.
 
 package loadbalancer
 
-// Image defines the loadbalancer image:tag
-const Image = "kindest/haproxy:v20210715-a6da3463"
+// Image defines the loadbalancer image name
+const Image = "haproxy"
+
+// DefaultImageRepository defines the loadbalancer image repository
+const DefaultImageRepository = "kindest"
+
+// DefaultImageTag defines the loadbalancer image tag
+const DefaultImageTag = "v20210715-a6da3463"
 
 // ConfigPath defines the path to the config file in the image
 const ConfigPath = "/usr/local/etc/haproxy/haproxy.cfg"