kubeadm: add means to create Node objects via the API client

cmd/kubeadm/app/phases/kubeconfig/kubeconfig_test.go

@@ -121,7 +121,7 @@ func TestGetKubeConfigSpecs(t *testing.T) {
 				organizations:  []string{kubeadmconstants.SystemPrivilegedGroup},
 			},
 			{
-				kubeConfigFile: kubeadmconstants.KubeletKubeConfigFileName,
+				kubeConfigFile: kubeadmconstants.KubeletBootstrapKubeConfigFileName,
 				clientName:     fmt.Sprintf("%s%s", kubeadmconstants.NodesUserPrefix, cfg.NodeRegistration.Name),
 				organizations:  []string{kubeadmconstants.NodesGroup},
 			},
@@ -557,8 +557,8 @@ func TestValidateKubeconfigsForExternalCA(t *testing.T) {
 		},
 		"some files don't exist": {
 			filesToWrite: map[string]*clientcmdapi.Config{
-				kubeadmconstants.AdminKubeConfigFileName:   config,
-				kubeadmconstants.KubeletKubeConfigFileName: config,
+				kubeadmconstants.AdminKubeConfigFileName:            config,
+				kubeadmconstants.KubeletBootstrapKubeConfigFileName: config,
 			},
 			initConfig:    initConfig,
 			expectedError: true,
@@ -566,7 +566,7 @@ func TestValidateKubeconfigsForExternalCA(t *testing.T) {
 		"some files have invalid CA": {
 			filesToWrite: map[string]*clientcmdapi.Config{
 				kubeadmconstants.AdminKubeConfigFileName:             config,
-				kubeadmconstants.KubeletKubeConfigFileName:           config,
+				kubeadmconstants.KubeletBootstrapKubeConfigFileName:  config,
 				kubeadmconstants.ControllerManagerKubeConfigFileName: configWithAnotherClusterCa,
 				kubeadmconstants.SchedulerKubeConfigFileName:         config,
 			},
@@ -576,7 +576,7 @@ func TestValidateKubeconfigsForExternalCA(t *testing.T) {
 		"some files have invalid Server Url": {
 			filesToWrite: map[string]*clientcmdapi.Config{
 				kubeadmconstants.AdminKubeConfigFileName:             config,
-				kubeadmconstants.KubeletKubeConfigFileName:           config,
+				kubeadmconstants.KubeletBootstrapKubeConfigFileName:  config,
 				kubeadmconstants.ControllerManagerKubeConfigFileName: config,
 				kubeadmconstants.SchedulerKubeConfigFileName:         configWithAnotherServerURL,
 			},
@@ -586,7 +586,7 @@ func TestValidateKubeconfigsForExternalCA(t *testing.T) {
 		"all files are valid": {
 			filesToWrite: map[string]*clientcmdapi.Config{
 				kubeadmconstants.AdminKubeConfigFileName:             config,
-				kubeadmconstants.KubeletKubeConfigFileName:           config,
+				kubeadmconstants.KubeletBootstrapKubeConfigFileName:  config,
 				kubeadmconstants.ControllerManagerKubeConfigFileName: config,
 				kubeadmconstants.SchedulerKubeConfigFileName:         config,
 			},

cmd/kubeadm/app/phases/markcontrolplane/BUILD

@@ -29,6 +29,7 @@ go_library(
         "//cmd/kubeadm/app/util/apiclient:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/klog:go_default_library",
     ],
 )
 

cmd/kubeadm/app/phases/markcontrolplane/markcontrolplane.go

@@ -19,14 +19,20 @@ package markcontrolplane
 import (
 	"fmt"
 
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/klog"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	"k8s.io/kubernetes/cmd/kubeadm/app/util/apiclient"
 )
 
 // MarkControlPlane taints the control-plane and sets the control-plane label
 func MarkControlPlane(client clientset.Interface, controlPlaneName string, taints []v1.Taint) error {
+	klog.V(1).Infof("[patchnode] Creating the Node API object %q if missing", controlPlaneName)
+	// See the comments for this function
+	if err := apiclient.EnsureNodeObject(client, controlPlaneName); err != nil {
+		return err
+	}
 
 	fmt.Printf("[mark-control-plane] Marking the node %s as control-plane by adding the label \"%s=''\"\n", controlPlaneName, constants.LabelNodeRoleMaster)
 

cmd/kubeadm/app/phases/markcontrolplane/markcontrolplane_test.go

@@ -24,7 +24,7 @@ import (
 	"net/http/httptest"
 	"testing"
 
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	clientset "k8s.io/client-go/kubernetes"
 	restclient "k8s.io/client-go/rest"
@@ -138,14 +138,9 @@ func TestMarkControlPlane(t *testing.T) {
 			s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
 				w.Header().Set("Content-Type", "application/json")
 
-				if req.URL.Path != "/api/v1/nodes/"+hostname {
-					t.Errorf("MarkControlPlane(%s): request for unexpected HTTP resource: %v", tc.name, req.URL.Path)
-					http.Error(w, "", http.StatusNotFound)
-					return
-				}
-
 				switch req.Method {
 				case "GET":
+				case "POST":
 				case "PATCH":
 					patchRequest = toString(req.Body)
 				default:

cmd/kubeadm/app/phases/patchnode/patchnode.go

@@ -17,7 +17,7 @@ limitations under the License.
 package patchnode
 
 import (
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/klog"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
@@ -26,9 +26,12 @@ import (
 
 // AnnotateCRISocket annotates the node with the given crisocket
 func AnnotateCRISocket(client clientset.Interface, nodeName string, criSocket string) error {
-
-	klog.V(1).Infof("[patchnode] Uploading the CRI Socket information %q to the Node API object %q as an annotation\n", criSocket, nodeName)
-
+	klog.V(1).Infof("[patchnode] Creating the Node API object %q if missing", nodeName)
+	// See the comments for this function
+	if err := apiclient.EnsureNodeObject(client, nodeName); err != nil {
+		return err
+	}
+	klog.V(1).Infof("[patchnode] Uploading the CRI Socket information %q to the Node API object %q as an annotation", criSocket, nodeName)
 	return apiclient.PatchNode(client, nodeName, func(n *v1.Node) {
 		annotateNodeWithCRISocket(n, criSocket)
 	})

cmd/kubeadm/app/util/apiclient/idempotency.go

@@ -285,6 +285,29 @@ func PatchNodeOnce(client clientset.Interface, nodeName string, patchFn func(*v1
 	}
 }
 
+// EnsureNodeObject creates a Node with the given name if the Node doesn't exist.
+// Adding a placeholder v1.LabelHostname label makes the object suitable for patching using PatchNodeOnce.
+//
+// Currently this function is used to make sure a Node object exists before patching it
+// during the "kubeadm init" phases. The creation of the Node object is delayed due to TLS boostrap
+// and instead of waiting for the object, we create it as a placeholder and patch it right away.
+// Later the same Node object is populated with dynamic values by the kubelet.
+func EnsureNodeObject(client clientset.Interface, nodeName string) error {
+	node := &v1.Node{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:   nodeName,
+			Labels: map[string]string{v1.LabelHostname: ""},
+		},
+	}
+	if _, err := client.CoreV1().Nodes().Create(node); err != nil {
+		if apierrors.IsAlreadyExists(err) {
+			return nil
+		}
+		return errors.Wrapf(err, "error creating Node %q", nodeName)
+	}
+	return nil
+}
+
 // PatchNode tries to patch a node using patchFn for the actual mutating logic.
 // Retries are provided by the wait package.
 func PatchNode(client clientset.Interface, nodeName string, patchFn func(*v1.Node)) error {