[kubelet]: Sync label periodically

pkg/kubelet/kubelet_node_status.go

@@ -509,11 +509,30 @@ func (kl *Kubelet) tryUpdateNodeStatus(tryNumber int) error {
 		}
 	}
 
+	areRequiredLabelsNotPresent := false
+	osName, osLabelExists := node.Labels[v1.LabelOSStable]
+	if !osLabelExists || osName != goruntime.GOOS {
+		if len(node.Labels) == 0 {
+			node.Labels = make(map[string]string)
+		}
+		node.Labels[v1.LabelOSStable] = goruntime.GOOS
+		areRequiredLabelsNotPresent = true
+	}
+	// Set the arch if there is a mismatch
+	arch, archLabelExists := node.Labels[v1.LabelArchStable]
+	if !archLabelExists || arch != goruntime.GOARCH {
+		if len(node.Labels) == 0 {
+			node.Labels = make(map[string]string)
+		}
+		node.Labels[v1.LabelArchStable] = goruntime.GOARCH
+		areRequiredLabelsNotPresent = true
+	}
+
 	kl.setNodeStatus(node)
 
 	now := kl.clock.Now()
 	if now.Before(kl.lastStatusReportTime.Add(kl.nodeStatusReportFrequency)) {
-		if !podCIDRChanged && !nodeStatusHasChanged(&originalNode.Status, &node.Status) {
+		if !podCIDRChanged && !nodeStatusHasChanged(&originalNode.Status, &node.Status) && !areRequiredLabelsNotPresent {
 			// We must mark the volumes as ReportedInUse in volume manager's dsw even
 			// if no changes were made to the node status (no volumes were added or removed
 			// from the VolumesInUse list).

pkg/kubelet/kubelet_node_status_test.go

@@ -217,7 +217,7 @@ func TestUpdateNewNodeStatus(t *testing.T) {
 			kubelet.setCachedMachineInfo(machineInfo)
 
 			expectedNode := &v1.Node{
-				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 				Spec:       v1.NodeSpec{},
 				Status: v1.NodeStatus{
 					Conditions: []v1.NodeCondition{
@@ -395,7 +395,7 @@ func TestUpdateExistingNodeStatus(t *testing.T) {
 	kubelet.setCachedMachineInfo(machineInfo)
 
 	expectedNode := &v1.Node{
-		ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+		ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 		Spec:       v1.NodeSpec{},
 		Status: v1.NodeStatus{
 			Conditions: []v1.NodeCondition{
@@ -601,7 +601,7 @@ func TestUpdateNodeStatusWithRuntimeStateError(t *testing.T) {
 	kubelet.setCachedMachineInfo(machineInfo)
 
 	expectedNode := &v1.Node{
-		ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+		ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 		Spec:       v1.NodeSpec{},
 		Status: v1.NodeStatus{
 			Conditions: []v1.NodeCondition{
@@ -822,7 +822,7 @@ func TestUpdateNodeStatusWithLease(t *testing.T) {
 
 	now := metav1.NewTime(clock.Now()).Rfc3339Copy()
 	expectedNode := &v1.Node{
-		ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+		ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 		Spec:       v1.NodeSpec{},
 		Status: v1.NodeStatus{
 			Conditions: []v1.NodeCondition{
@@ -1033,13 +1033,13 @@ func TestUpdateNodeStatusAndVolumesInUseWithNodeLease(t *testing.T) {
 	}{
 		{
 			desc:         "no volumes and no update",
-			existingNode: &v1.Node{ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname}},
+			existingNode: &v1.Node{ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}}},
 		},
 		{
 			desc:            "volumes inuse on node and volumeManager",
 			existingVolumes: []v1.UniqueVolumeName{"vol1"},
 			existingNode: &v1.Node{
-				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 				Status: v1.NodeStatus{
 					VolumesInUse: []v1.UniqueVolumeName{"vol1"},
 				},
@@ -1054,14 +1054,14 @@ func TestUpdateNodeStatusAndVolumesInUseWithNodeLease(t *testing.T) {
 					VolumesInUse: []v1.UniqueVolumeName{"vol1"},
 				},
 			},
-			expectedNode: &v1.Node{ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname}},
+			expectedNode: &v1.Node{ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}}},
 		},
 		{
 			desc:            "volumes inuse in volumeManager but not on node",
 			existingVolumes: []v1.UniqueVolumeName{"vol1"},
 			existingNode:    &v1.Node{ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname}},
 			expectedNode: &v1.Node{
-				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 				Status: v1.NodeStatus{
 					VolumesInUse: []v1.UniqueVolumeName{"vol1"},
 				},
@@ -2819,7 +2819,7 @@ func TestUpdateNodeAddresses(t *testing.T) {
 				},
 			}
 			expectedNode := &v1.Node{
-				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname},
+				ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}},
 				Spec:       v1.NodeSpec{},
 				Status: v1.NodeStatus{
 					Addresses: test.After,

pkg/kubelet/kubelet_test.go

@@ -22,6 +22,7 @@ import (
 	"io/ioutil"
 	"os"
 	"reflect"
+	goruntime "runtime"
 	"sort"
 	"strconv"
 	"testing"
@@ -30,6 +31,7 @@ import (
 	cadvisorapi "github.com/google/cadvisor/info/v1"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	core "k8s.io/client-go/testing"
 	"k8s.io/mount-utils"
 
 	v1 "k8s.io/api/core/v1"
@@ -858,6 +860,71 @@ func TestHandleNodeSelector(t *testing.T) {
 	checkPodStatus(t, kl, fittingPod, v1.PodPending)
 }
 
+// Tests that we handle not matching labels selector correctly by setting the failed status in status map.
+func TestHandleNodeSelectorBasedOnOS(t *testing.T) {
+	tests := []struct {
+		name        string
+		nodeLabels  map[string]string
+		podSelector map[string]string
+		podStatus   v1.PodPhase
+	}{
+		{
+			name:        "correct OS label, wrong pod selector, admission denied",
+			nodeLabels:  map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH},
+			podSelector: map[string]string{v1.LabelOSStable: "dummyOS"},
+			podStatus:   v1.PodFailed,
+		},
+		{
+			name:        "correct OS label, correct pod selector, admission denied",
+			nodeLabels:  map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH},
+			podSelector: map[string]string{v1.LabelOSStable: goruntime.GOOS},
+			podStatus:   v1.PodPending,
+		},
+		{
+			// Expect no patching to happen, label B should be preserved and can be used for nodeAffinity.
+			name:        "new node label, correct pod selector, admitted",
+			nodeLabels:  map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH, "key": "B"},
+			podSelector: map[string]string{"key": "B"},
+			podStatus:   v1.PodPending,
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			testKubelet := newTestKubelet(t, false /* controllerAttachDetachEnabled */)
+			defer testKubelet.Cleanup()
+			kl := testKubelet.kubelet
+			nodes := []*v1.Node{
+				{
+					ObjectMeta: metav1.ObjectMeta{Name: testKubeletHostname, Labels: test.nodeLabels},
+					Status: v1.NodeStatus{
+						Allocatable: v1.ResourceList{
+							v1.ResourcePods: *resource.NewQuantity(110, resource.DecimalSI),
+						},
+					},
+				},
+			}
+			kl.nodeLister = testNodeLister{nodes: nodes}
+
+			recorder := record.NewFakeRecorder(20)
+			nodeRef := &v1.ObjectReference{
+				Kind:      "Node",
+				Name:      string("testNode"),
+				UID:       types.UID("testNode"),
+				Namespace: "",
+			}
+			testClusterDNSDomain := "TEST"
+			kl.dnsConfigurer = dns.NewConfigurer(recorder, nodeRef, nil, nil, testClusterDNSDomain, "")
+
+			pod := podWithUIDNameNsSpec("123456789", "podA", "foo", v1.PodSpec{NodeSelector: test.podSelector})
+
+			kl.HandlePodAdditions([]*v1.Pod{pod})
+
+			// Check pod status stored in the status map.
+			checkPodStatus(t, kl, pod, test.podStatus)
+		})
+	}
+}
+
 // Tests that we handle exceeded resources correctly by setting the failed status in status map.
 func TestHandleMemExceeded(t *testing.T) {
 	testKubelet := newTestKubelet(t, false /* controllerAttachDetachEnabled */)
@@ -2291,6 +2358,97 @@ func TestPreInitRuntimeService(t *testing.T) {
 	}
 }
 
+func TestSyncLabels(t *testing.T) {
+	tests := []struct {
+		name             string
+		existingNode     *v1.Node
+		isPatchingNeeded bool
+	}{
+		{
+			name:             "no labels",
+			existingNode:     &v1.Node{ObjectMeta: metav1.ObjectMeta{Labels: map[string]string{}}},
+			isPatchingNeeded: true,
+		},
+		{
+			name:             "wrong labels",
+			existingNode:     &v1.Node{ObjectMeta: metav1.ObjectMeta{Labels: map[string]string{v1.LabelOSStable: "dummyOS", v1.LabelArchStable: "dummyArch"}}},
+			isPatchingNeeded: true,
+		},
+		{
+			name:             "correct labels",
+			existingNode:     &v1.Node{ObjectMeta: metav1.ObjectMeta{Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: goruntime.GOARCH}}},
+			isPatchingNeeded: false,
+		},
+		{
+			name:             "partially correct labels",
+			existingNode:     &v1.Node{ObjectMeta: metav1.ObjectMeta{Labels: map[string]string{v1.LabelOSStable: goruntime.GOOS, v1.LabelArchStable: "dummyArch"}}},
+			isPatchingNeeded: true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			testKubelet := newTestKubelet(t, false)
+			defer testKubelet.Cleanup()
+			kl := testKubelet.kubelet
+			kubeClient := testKubelet.fakeKubeClient
+
+			test.existingNode.Name = string(kl.nodeName)
+
+			kl.nodeLister = testNodeLister{nodes: []*v1.Node{test.existingNode}}
+			go func() { kl.syncNodeStatus() }()
+
+			err := retryWithExponentialBackOff(
+				100*time.Millisecond,
+				func() (bool, error) {
+					var savedNode *v1.Node
+					if test.isPatchingNeeded {
+						actions := kubeClient.Actions()
+						if len(actions) == 0 {
+							t.Logf("No action yet")
+							return false, nil
+						}
+						action := actions[1]
+						if action.GetVerb() == "patch" {
+							patchAction := action.(core.PatchActionImpl)
+							var err error
+							savedNode, err = applyNodeStatusPatch(test.existingNode, patchAction.GetPatch())
+							if err != nil {
+								t.Logf("node patching failed, %v", err)
+								return false, nil
+							}
+						}
+					} else {
+						savedNode = test.existingNode
+					}
+					val, ok := savedNode.Labels[v1.LabelOSStable]
+					if !ok {
+						t.Logf("expected kubernetes.io/os label to be present")
+						return false, nil
+					}
+					if val != goruntime.GOOS {
+						t.Logf("expected kubernetes.io/os to match runtime.GOOS but got %v", val)
+						return false, nil
+					}
+					val, ok = savedNode.Labels[v1.LabelArchStable]
+					if !ok {
+						t.Logf("expected kubernetes.io/arch label to be present")
+						return false, nil
+					}
+					if val != goruntime.GOARCH {
+						t.Logf("expected kubernetes.io/arch to match runtime.GOARCH but got %v", val)
+						return false, nil
+					}
+					return true, nil
+				},
+			)
+			if err != nil {
+				t.Fatalf("expected labels to be reconciled but it failed with %v", err)
+			}
+		})
+	}
+}
+
 func waitForVolumeUnmount(
 	volumeManager kubeletvolume.VolumeManager,
 	pod *v1.Pod) error {

pkg/util/node/node.go

@@ -251,7 +251,7 @@ func PatchNodeCIDRs(c clientset.Interface, node types.NodeName, cidrs []string)
 	return nil
 }
 
-// PatchNodeStatus patches node status.
+// PatchNodeStatus patches node status along with objectmetadata
 func PatchNodeStatus(c v1core.CoreV1Interface, nodeName types.NodeName, oldNode *v1.Node, newNode *v1.Node) (*v1.Node, []byte, error) {
 	patchBytes, err := preparePatchBytesforNodeStatus(nodeName, oldNode, newNode)
 	if err != nil {
@@ -265,6 +265,7 @@ func PatchNodeStatus(c v1core.CoreV1Interface, nodeName types.NodeName, oldNode
 	return updatedNode, patchBytes, nil
 }
 
+// preparePatchBytesforNodeStatus updates the node objectmetadata and status
 func preparePatchBytesforNodeStatus(nodeName types.NodeName, oldNode *v1.Node, newNode *v1.Node) ([]byte, error) {
 	oldData, err := json.Marshal(oldNode)
 	if err != nil {