feat: add linode UUID as a metadata to each node

Makefile

@@ -64,9 +64,8 @@ imgname:
 	echo IMG=${IMG}
 
 .PHONY: docker-build
-# we cross compile the binary for linux, then build a container
-docker-build: build-linux
-	docker build . -t ${IMG}
+docker-build:
+	docker build --platform=linux/amd64 --tag=${IMG} .
 
 .PHONY: docker-push
 # must run the docker build before pushing the image

cloud/linode/annotations.go

@@ -0,0 +1,33 @@
+package linode
+
+const (
+	// annLinodeDefaultProtocol is the annotation used to specify the default protocol
+	// for Linode load balancers. Options are tcp, http and https. Defaults to tcp.
+	annLinodeDefaultProtocol      = "service.beta.kubernetes.io/linode-loadbalancer-default-protocol"
+	annLinodePortConfigPrefix     = "service.beta.kubernetes.io/linode-loadbalancer-port-"
+	annLinodeDefaultProxyProtocol = "service.beta.kubernetes.io/linode-loadbalancer-default-proxy-protocol"
+
+	annLinodeCheckPath       = "service.beta.kubernetes.io/linode-loadbalancer-check-path"
+	annLinodeCheckBody       = "service.beta.kubernetes.io/linode-loadbalancer-check-body"
+	annLinodeHealthCheckType = "service.beta.kubernetes.io/linode-loadbalancer-check-type"
+
+	annLinodeHealthCheckInterval = "service.beta.kubernetes.io/linode-loadbalancer-check-interval"
+	annLinodeHealthCheckTimeout  = "service.beta.kubernetes.io/linode-loadbalancer-check-timeout"
+	annLinodeHealthCheckAttempts = "service.beta.kubernetes.io/linode-loadbalancer-check-attempts"
+	annLinodeHealthCheckPassive  = "service.beta.kubernetes.io/linode-loadbalancer-check-passive"
+
+	// annLinodeThrottle is the annotation specifying the value of the Client Connection
+	// Throttle, which limits the number of subsequent new connections per second from the
+	// same client IP. Options are a number between 1-20, or 0 to disable. Defaults to 20.
+	annLinodeThrottle = "service.beta.kubernetes.io/linode-loadbalancer-throttle"
+
+	annLinodeLoadBalancerPreserve = "service.beta.kubernetes.io/linode-loadbalancer-preserve"
+	annLinodeNodeBalancerID       = "service.beta.kubernetes.io/linode-loadbalancer-nodebalancer-id"
+
+	annLinodeHostnameOnlyIngress = "service.beta.kubernetes.io/linode-loadbalancer-hostname-only-ingress"
+	annLinodeLoadBalancerTags    = "service.beta.kubernetes.io/linode-loadbalancer-tags"
+	annLinodeCloudFirewallID     = "service.beta.kubernetes.io/linode-loadbalancer-firewall-id"
+
+	annLinodeNodePrivateIP = "node.k8s.linode.com/private-ip"
+	annLinodeHostUUID      = "node.k8s.linode.com/host-uuid"
+)

cloud/linode/client.go

@@ -4,6 +4,8 @@ package linode
 
 import (
 	"context"
+	"net/url"
+	"regexp"
 
 	"github.com/linode/linodego"
 )
@@ -27,3 +29,33 @@ type Client interface {
 
 // linodego.Client implements Client
 var _ Client = (*linodego.Client)(nil)
+
+func newLinodeClient(token, ua, apiURL string) (*linodego.Client, error) {
+	linodeClient := linodego.NewClient(nil)
+	linodeClient.SetUserAgent(ua)
+	linodeClient.SetToken(token)
+
+	// Validate apiURL
+	parsedURL, err := url.Parse(apiURL)
+	if err != nil {
+		return nil, err
+	}
+
+	validatedURL := &url.URL{
+		Host:   parsedURL.Host,
+		Scheme: parsedURL.Scheme,
+	}
+
+	linodeClient.SetBaseURL(validatedURL.String())
+
+	version := ""
+	matches := regexp.MustCompile(`/v\d+`).FindAllString(parsedURL.Path, -1)
+
+	if len(matches) > 0 {
+		version = matches[len(matches)-1]
+	}
+
+	linodeClient.SetAPIVersion(version)
+
+	return &linodeClient, nil
+}

cloud/linode/cloud.go

@@ -16,6 +16,7 @@ const (
 	ProviderName   = "linode"
 	accessTokenEnv = "LINODE_API_TOKEN"
 	regionEnv      = "LINODE_REGION"
+	urlEnv         = "LINODE_URL"
 )
 
 // Options is a configuration object for this cloudprovider implementation.
@@ -52,28 +53,37 @@ func newCloud() (cloudprovider.Interface, error) {
 		return nil, fmt.Errorf("%s must be set in the environment (use a k8s secret)", regionEnv)
 	}
 
-	linodeClient := linodego.NewClient(nil)
-	linodeClient.SetToken(apiToken)
+	url := os.Getenv(urlEnv)
+	ua := fmt.Sprintf("linode-cloud-controller-manager %s", linodego.DefaultUserAgent)
+
+	linodeClient, err := newLinodeClient(apiToken, ua, url)
+	if err != nil {
+		return nil, fmt.Errorf("client was not created succesfully: %w", err)
+	}
+
 	if Options.LinodeGoDebug {
 		linodeClient.SetDebug(true)
 	}
-	linodeClient.SetUserAgent(fmt.Sprintf("linode-cloud-controller-manager %s", linodego.DefaultUserAgent))
 
 	// Return struct that satisfies cloudprovider.Interface
 	return &linodeCloud{
-		client:        &linodeClient,
-		instances:     newInstances(&linodeClient),
-		loadbalancers: newLoadbalancers(&linodeClient, region),
+		client:        linodeClient,
+		instances:     newInstances(linodeClient),
+		loadbalancers: newLoadbalancers(linodeClient, region),
 	}, nil
 }
 
 func (c *linodeCloud) Initialize(clientBuilder cloudprovider.ControllerClientBuilder, stopCh <-chan struct{}) {
 	kubeclient := clientBuilder.ClientOrDie("linode-shared-informers")
 	sharedInformer := informers.NewSharedInformerFactory(kubeclient, 0)
 	serviceInformer := sharedInformer.Core().V1().Services()
+	nodeInformer := sharedInformer.Core().V1().Nodes()
 
 	serviceController := newServiceController(c.loadbalancers.(*loadbalancers), serviceInformer)
 	go serviceController.Run(stopCh)
+
+	nodeController := newNodeController(kubeclient, c.client, nodeInformer)
+	go nodeController.Run(stopCh)
 }
 
 func (c *linodeCloud) LoadBalancer() (cloudprovider.LoadBalancer, bool) {

cloud/linode/instances.go

@@ -52,7 +52,7 @@ type instances struct {
 	nodeCache *nodeCache
 }
 
-func newInstances(client Client) cloudprovider.InstancesV2 {
+func newInstances(client Client) *instances {
 	var timeout int
 	if raw, ok := os.LookupEnv("LINODE_INSTANCE_CACHE_TTL"); ok {
 		timeout, _ = strconv.Atoi(raw)

cloud/linode/loadbalancers.go

@@ -24,37 +24,6 @@ import (
 	"github.com/linode/linodego"
 )
 
-const (
-	// annLinodeDefaultProtocol is the annotation used to specify the default protocol
-	// for Linode load balancers. Options are tcp, http and https. Defaults to tcp.
-	annLinodeDefaultProtocol      = "service.beta.kubernetes.io/linode-loadbalancer-default-protocol"
-	annLinodePortConfigPrefix     = "service.beta.kubernetes.io/linode-loadbalancer-port-"
-	annLinodeDefaultProxyProtocol = "service.beta.kubernetes.io/linode-loadbalancer-default-proxy-protocol"
-
-	annLinodeCheckPath       = "service.beta.kubernetes.io/linode-loadbalancer-check-path"
-	annLinodeCheckBody       = "service.beta.kubernetes.io/linode-loadbalancer-check-body"
-	annLinodeHealthCheckType = "service.beta.kubernetes.io/linode-loadbalancer-check-type"
-
-	annLinodeHealthCheckInterval = "service.beta.kubernetes.io/linode-loadbalancer-check-interval"
-	annLinodeHealthCheckTimeout  = "service.beta.kubernetes.io/linode-loadbalancer-check-timeout"
-	annLinodeHealthCheckAttempts = "service.beta.kubernetes.io/linode-loadbalancer-check-attempts"
-	annLinodeHealthCheckPassive  = "service.beta.kubernetes.io/linode-loadbalancer-check-passive"
-
-	// annLinodeThrottle is the annotation specifying the value of the Client Connection
-	// Throttle, which limits the number of subsequent new connections per second from the
-	// same client IP. Options are a number between 1-20, or 0 to disable. Defaults to 20.
-	annLinodeThrottle = "service.beta.kubernetes.io/linode-loadbalancer-throttle"
-
-	annLinodeLoadBalancerPreserve = "service.beta.kubernetes.io/linode-loadbalancer-preserve"
-	annLinodeNodeBalancerID       = "service.beta.kubernetes.io/linode-loadbalancer-nodebalancer-id"
-
-	annLinodeHostnameOnlyIngress = "service.beta.kubernetes.io/linode-loadbalancer-hostname-only-ingress"
-	annLinodeLoadBalancerTags    = "service.beta.kubernetes.io/linode-loadbalancer-tags"
-	annLinodeCloudFirewallID     = "service.beta.kubernetes.io/linode-loadbalancer-firewall-id"
-
-	annLinodeNodePrivateIP = "node.k8s.linode.com/private-ip"
-)
-
 var errNoNodesAvailable = errors.New("no nodes available for nodebalancer")
 
 type lbNotFoundError struct {

cloud/linode/node_controller.go

@@ -0,0 +1,124 @@
+package linode
+
+import (
+	"context"
+	"net/http"
+	"time"
+
+	"github.com/appscode/go/wait"
+	"github.com/linode/linodego"
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	v1informers "k8s.io/client-go/informers/core/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/tools/cache"
+	"k8s.io/client-go/util/workqueue"
+	"k8s.io/klog/v2"
+)
+
+type nodeController struct {
+	client     Client
+	instances  *instances
+	kubeclient kubernetes.Interface
+	informer   v1informers.NodeInformer
+
+	queue workqueue.DelayingInterface
+}
+
+func newNodeController(kubeclient kubernetes.Interface, client Client, informer v1informers.NodeInformer) *nodeController {
+	return &nodeController{
+		client:     client,
+		instances:  newInstances(client),
+		kubeclient: kubeclient,
+		informer:   informer,
+		queue:      workqueue.NewDelayingQueue(),
+	}
+}
+
+func (s *nodeController) Run(stopCh <-chan struct{}) {
+	s.informer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
+		AddFunc: func(obj interface{}) {
+			node, ok := obj.(*v1.Node)
+			if !ok {
+				return
+			}
+
+			klog.Infof("NodeController will handle newly created node (%s) metadata", node.Name)
+			s.queue.Add(node)
+		},
+		UpdateFunc: func(_, new interface{}) {
+			node, ok := new.(*v1.Node)
+			if !ok {
+				return
+			}
+
+			klog.Infof("NodeController will handle updated node (%s) metadata", node.Name)
+			s.queue.Add(node)
+		},
+	})
+
+	go wait.Until(s.worker, time.Second, stopCh)
+	s.informer.Informer().Run(stopCh)
+}
+
+// worker runs a worker thread that dequeues new or modified nodes and processes
+// metadata (host UUID) on each of them.
+func (s *nodeController) worker() {
+	for s.processNext() {
+	}
+}
+
+func (s *nodeController) processNext() bool {
+	key, quit := s.queue.Get()
+	if quit {
+		return false
+	}
+	defer s.queue.Done(key)
+
+	node, ok := key.(*v1.Node)
+	if !ok {
+		klog.Errorf("expected dequeued key to be of type *v1.Node but got %T", node)
+		return true
+	}
+
+	err := s.handleNodeAdded(context.TODO(), node)
+	switch deleteErr := err.(type) {
+	case nil:
+		break
+
+	case *linodego.Error:
+		if deleteErr.Code >= http.StatusInternalServerError || deleteErr.Code == http.StatusTooManyRequests {
+			klog.Errorf("failed to add metadata for node (%s); retrying in 1 minute: %s", node.Name, err)
+			s.queue.AddAfter(node, retryInterval)
+		}
+
+	default:
+		klog.Errorf("failed to add metadata for node (%s); will not retry: %s", node.Name, err)
+	}
+	return true
+}
+
+func (s *nodeController) handleNodeAdded(ctx context.Context, node *v1.Node) error {
+	klog.Infof("NodeController handling node (%s) addition", node.Name)
+
+	linode, err := s.instances.lookupLinode(ctx, node)
+	if err != nil {
+		klog.Infof("instance lookup error: %s", err.Error())
+		return err
+	}
+
+	uuid, ok := node.Labels[annLinodeHostUUID]
+	if ok && uuid == linode.HostUUID {
+		return nil
+	}
+
+	node.Labels[annLinodeHostUUID] = linode.HostUUID
+
+	_, err = s.kubeclient.CoreV1().Nodes().Update(ctx, node, metav1.UpdateOptions{})
+	if err != nil {
+		klog.Infof("node update error: %s", err.Error())
+		return err
+	}
+
+	return nil
+}