fix node provider race condition

cmd/virtual-kubelet/root/root.go

@@ -162,7 +162,8 @@ func runRootCommand(ctx context.Context, s *provider.Store, c *Opts) error {
 		networkReadyChan := liqoProvider.GetNetworkReadyChan()
 
 		liqoNodeProvider, err := liqonodeprovider.NewLiqoNodeProvider(c.NodeName, advName, c.ForeignClusterId,
-			c.KubeletNamespace, podProviderStopper, networkReadyChan, nil, c.LiqoInformerResyncPeriod, c.UseNewAuth)
+			c.KubeletNamespace, pNode, podProviderStopper, networkReadyChan, nil, c.LiqoInformerResyncPeriod,
+			c.UseNewAuth)
 		if err != nil {
 			klog.Fatal(err)
 		}

pkg/utils/maps.go

@@ -0,0 +1,20 @@
+package utils
+
+// MergeMaps merges two maps.
+func MergeMaps(m1, m2 map[string]string) map[string]string {
+	if m1 == nil {
+		return m2
+	}
+	for k, v := range m2 {
+		m1[k] = v
+	}
+	return m1
+}
+
+// SubMaps removes elements of m2 from m1.
+func SubMaps(m1, m2 map[string]string) map[string]string {
+	for k := range m2 {
+		delete(m1, k)
+	}
+	return m1
+}

pkg/virtualKubelet/liqoNodeProvider/nodeProvider.go

@@ -15,6 +15,9 @@ type LiqoNodeProvider struct {
 	client    kubernetes.Interface
 	dynClient dynamic.Interface
 
+	node      *corev1.Node
+	oldLabels map[string]string
+
 	nodeName         string
 	advName          string
 	foreignClusterID string

pkg/virtualKubelet/liqoNodeProvider/nodeProvider_test.go

@@ -10,10 +10,12 @@ import (
 	. "github.com/onsi/ginkgo/extensions/table"
 	. "github.com/onsi/gomega"
 	v1 "k8s.io/api/core/v1"
+
 	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/client-go/dynamic"
 	"k8s.io/client-go/kubernetes"
 
@@ -65,14 +67,14 @@ var _ = Describe("NodeProvider", func() {
 				Name: nodeName,
 			},
 		}
-		_, err = client.CoreV1().Nodes().Create(ctx, node, metav1.CreateOptions{})
+		node, err = client.CoreV1().Nodes().Create(ctx, node, metav1.CreateOptions{})
 		Expect(err).To(BeNil())
 
 		podStopper = make(chan struct{}, 1)
 		networkStopper = make(chan struct{}, 1)
 		nodeChan = make(chan *v1.Node, 10)
 
-		nodeProvider, err = NewLiqoNodeProvider(nodeName, advName, foreignClusterID, kubeletNamespace, podStopper, networkStopper, cluster.GetCfg(), 0, false)
+		nodeProvider, err = NewLiqoNodeProvider(nodeName, advName, foreignClusterID, kubeletNamespace, node, podStopper, networkStopper, cluster.GetCfg(), 0, false)
 		Expect(err).To(BeNil())
 
 		nodeProvider.NotifyNodeStatus(ctx, func(node *v1.Node) {
@@ -309,4 +311,75 @@ var _ = Describe("NodeProvider", func() {
 		}),
 	)
 
+	It("Labels patch", func() {
+
+		By("Add labels")
+
+		labels := map[string]string{
+			"test1": "value1",
+			"test2": "value2",
+		}
+
+		patch, err := nodeProvider.getLabelsPatch(labels)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(patch).ToNot(BeNil())
+
+		client := kubernetes.NewForConfigOrDie(cluster.GetCfg())
+		node, err := client.CoreV1().Nodes().Patch(context.TODO(),
+			nodeName, types.JSONPatchType, patch, metav1.PatchOptions{})
+		Expect(err).ToNot(HaveOccurred())
+
+		nodeLabels := node.GetLabels()
+		v, ok := nodeLabels["test1"]
+		Expect(ok).To(BeTrue())
+		Expect(v).To(Equal("value1"))
+		v, ok = nodeLabels["test2"]
+		Expect(ok).To(BeTrue())
+		Expect(v).To(Equal("value2"))
+
+		By("Update labels")
+
+		labels = map[string]string{
+			"test1": "value3",
+			"test2": "value4",
+		}
+
+		patch, err = nodeProvider.getLabelsPatch(labels)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(patch).ToNot(BeNil())
+
+		node, err = client.CoreV1().Nodes().Patch(context.TODO(),
+			nodeName, types.JSONPatchType, patch, metav1.PatchOptions{})
+		Expect(err).ToNot(HaveOccurred())
+
+		nodeLabels = node.GetLabels()
+		v, ok = nodeLabels["test1"]
+		Expect(ok).To(BeTrue())
+		Expect(v).To(Equal("value3"))
+		v, ok = nodeLabels["test2"]
+		Expect(ok).To(BeTrue())
+		Expect(v).To(Equal("value4"))
+
+		By("Delete labels")
+
+		labels = map[string]string{
+			"test1": "value3",
+		}
+
+		patch, err = nodeProvider.getLabelsPatch(labels)
+		Expect(err).ToNot(HaveOccurred())
+		Expect(patch).ToNot(BeNil())
+
+		node, err = client.CoreV1().Nodes().Patch(context.TODO(),
+			nodeName, types.JSONPatchType, patch, metav1.PatchOptions{})
+		Expect(err).ToNot(HaveOccurred())
+
+		nodeLabels = node.GetLabels()
+		v, ok = nodeLabels["test1"]
+		Expect(ok).To(BeTrue())
+		Expect(v).To(Equal("value3"))
+		_, ok = nodeLabels["test2"]
+		Expect(ok).To(BeFalse())
+	})
+
 })