Add e2enode.GetRandomReadySchedulableNode, replace some uses of framework.GetReadySchedulableNodesOrDie

For tests that want a single ready, schedulable node

test/e2e/apps/daemon_set.go

@@ -160,9 +160,9 @@ var _ = SIGDescribe("Daemon set [Serial]", func() {
 		framework.ExpectNoError(err, "error waiting for daemon pods to be running on no nodes")
 
 		ginkgo.By("Change node label to blue, check that daemon pod is launched.")
-		nodeList := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+		node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-		gomega.Expect(len(nodeList.Items)).To(gomega.BeNumerically(">", 0))
+		framework.ExpectNoError(err)
-		newNode, err := setDaemonSetNodeLabels(c, nodeList.Items[0].Name, nodeSelector)
+		newNode, err := setDaemonSetNodeLabels(c, node.Name, nodeSelector)
 		framework.ExpectNoError(err, "error setting labels on node")
 		daemonSetLabels, _ := separateDaemonSetNodeLabels(newNode.Labels)
 		framework.ExpectEqual(len(daemonSetLabels), 1)
@@ -173,7 +173,7 @@ var _ = SIGDescribe("Daemon set [Serial]", func() {
 
 		ginkgo.By("Update the node label to green, and wait for daemons to be unscheduled")
 		nodeSelector[daemonsetColorLabel] = "green"
-		greenNode, err := setDaemonSetNodeLabels(c, nodeList.Items[0].Name, nodeSelector)
+		greenNode, err := setDaemonSetNodeLabels(c, node.Name, nodeSelector)
 		framework.ExpectNoError(err, "error removing labels on node")
 		err = wait.PollImmediate(dsRetryPeriod, dsRetryTimeout, checkRunningOnNoNodes(f, ds))
 		framework.ExpectNoError(err, "error waiting for daemon pod to not be running on nodes")
@@ -223,9 +223,9 @@ var _ = SIGDescribe("Daemon set [Serial]", func() {
 		framework.ExpectNoError(err, "error waiting for daemon pods to be running on no nodes")
 
 		ginkgo.By("Change node label to blue, check that daemon pod is launched.")
-		nodeList := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+		node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-		gomega.Expect(len(nodeList.Items)).To(gomega.BeNumerically(">", 0))
+		framework.ExpectNoError(err)
-		newNode, err := setDaemonSetNodeLabels(c, nodeList.Items[0].Name, nodeSelector)
+		newNode, err := setDaemonSetNodeLabels(c, node.Name, nodeSelector)
 		framework.ExpectNoError(err, "error setting labels on node")
 		daemonSetLabels, _ := separateDaemonSetNodeLabels(newNode.Labels)
 		framework.ExpectEqual(len(daemonSetLabels), 1)
@@ -235,7 +235,7 @@ var _ = SIGDescribe("Daemon set [Serial]", func() {
 		framework.ExpectNoError(err)
 
 		ginkgo.By("Remove the node label and wait for daemons to be unscheduled")
-		_, err = setDaemonSetNodeLabels(c, nodeList.Items[0].Name, map[string]string{})
+		_, err = setDaemonSetNodeLabels(c, node.Name, map[string]string{})
 		framework.ExpectNoError(err, "error removing labels on node")
 		err = wait.PollImmediate(dsRetryPeriod, dsRetryTimeout, checkRunningOnNoNodes(f, ds))
 		framework.ExpectNoError(err, "error waiting for daemon pod to not be running on nodes")

test/e2e/apps/statefulset.go

@@ -34,6 +34,7 @@ import (
 	clientset "k8s.io/client-go/kubernetes"
 	watchtools "k8s.io/client-go/tools/watch"
 	"k8s.io/kubernetes/test/e2e/framework"
+	e2enode "k8s.io/kubernetes/test/e2e/framework/node"
 	e2epod "k8s.io/kubernetes/test/e2e/framework/pod"
 	e2epv "k8s.io/kubernetes/test/e2e/framework/pv"
 	e2eservice "k8s.io/kubernetes/test/e2e/framework/service"
@@ -679,8 +680,8 @@ var _ = SIGDescribe("StatefulSet", func() {
 			podName := "test-pod"
 			statefulPodName := ssName + "-0"
 			ginkgo.By("Looking for a node to schedule stateful set and pod")
-			nodes := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+			node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-			node := nodes.Items[0]
+			framework.ExpectNoError(err)
 
 			ginkgo.By("Creating pod with conflicting port in namespace " + f.Namespace.Name)
 			conflictingPort := v1.ContainerPort{HostPort: 21017, ContainerPort: 21017, Name: "conflict"}
@@ -699,7 +700,7 @@ var _ = SIGDescribe("StatefulSet", func() {
 					NodeName: node.Name,
 				},
 			}
-			pod, err := f.ClientSet.CoreV1().Pods(f.Namespace.Name).Create(pod)
+			pod, err = f.ClientSet.CoreV1().Pods(f.Namespace.Name).Create(pod)
 			framework.ExpectNoError(err)
 
 			ginkgo.By("Creating statefulset with conflicting port in namespace " + f.Namespace.Name)

test/e2e/cloud/nodes.go

@@ -43,8 +43,8 @@ var _ = SIGDescribe("[Feature:CloudProvider][Disruptive] Nodes", func() {
 	ginkgo.It("should be deleted on API server if it doesn't exist in the cloud provider", func() {
 		ginkgo.By("deleting a node on the cloud provider")
 
-		nodeDeleteCandidates := framework.GetReadySchedulableNodesOrDie(c)
+		nodeToDelete, err := e2enode.GetRandomReadySchedulableNode(c)
-		nodeToDelete := nodeDeleteCandidates.Items[0]
+		framework.ExpectNoError(err)
 
 		origNodes, err := e2enode.GetReadyNodesIncludingTainted(c)
 		if err != nil {
@@ -55,7 +55,7 @@ var _ = SIGDescribe("[Feature:CloudProvider][Disruptive] Nodes", func() {
 
 		framework.Logf("Original number of ready nodes: %d", len(origNodes.Items))
 
-		err = framework.DeleteNodeOnCloudProvider(&nodeToDelete)
+		err = framework.DeleteNodeOnCloudProvider(nodeToDelete)
 		if err != nil {
 			framework.Failf("failed to delete node %q, err: %q", nodeToDelete.Name, err)
 		}

test/e2e/common/node_lease.go

@@ -41,9 +41,9 @@ var _ = framework.KubeDescribe("NodeLease", func() {
 	f := framework.NewDefaultFramework("node-lease-test")
 
 	ginkgo.BeforeEach(func() {
-		nodes := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+		node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-		gomega.Expect(len(nodes.Items)).NotTo(gomega.BeZero())
+		framework.ExpectNoError(err)
-		nodeName = nodes.Items[0].ObjectMeta.Name
+		nodeName = node.Name
 	})
 
 	ginkgo.Context("when the NodeLease feature is enabled", func() {

test/e2e/framework/node/resource.go

@@ -371,6 +371,16 @@ func GetBoundedReadySchedulableNodes(c clientset.Interface, maxNodes int) (nodes
 	return nodes, nil
 }
 
+// GetRandomReadySchedulableNode gets a single randomly-selected node which is available for
+// running pods on. If there are no available nodes it will return an error.
+func GetRandomReadySchedulableNode(c clientset.Interface) (*v1.Node, error) {
+	nodes, err := GetReadySchedulableNodes(c)
+	if err != nil {
+		return nil, err
+	}
+	return &nodes.Items[rand.Intn(len(nodes.Items))], nil
+}
+
 // GetReadyNodesIncludingTainted returns all ready nodes, even those which are tainted.
 // There are cases when we care about tainted nodes
 // E.g. in tests related to nodes with gpu we care about nodes despite

test/e2e/instrumentation/monitoring/BUILD

@@ -39,6 +39,7 @@ go_library(
         "//test/e2e/framework/config:go_default_library",
         "//test/e2e/framework/gpu:go_default_library",
         "//test/e2e/framework/metrics:go_default_library",
+        "//test/e2e/framework/node:go_default_library",
         "//test/e2e/framework/pod:go_default_library",
         "//test/e2e/instrumentation/common:go_default_library",
         "//test/e2e/scheduling:go_default_library",

test/e2e/instrumentation/monitoring/metrics_grabber.go

@@ -23,6 +23,7 @@ import (
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/kubernetes/test/e2e/framework"
 	"k8s.io/kubernetes/test/e2e/framework/metrics"
+	e2enode "k8s.io/kubernetes/test/e2e/framework/node"
 	instrumentation "k8s.io/kubernetes/test/e2e/instrumentation/common"
 
 	gin "github.com/onsi/ginkgo"
@@ -51,9 +52,9 @@ var _ = instrumentation.SIGDescribe("MetricsGrabber", func() {
 
 	gin.It("should grab all metrics from a Kubelet.", func() {
 		gin.By("Proxying to Node through the API server")
-		nodes := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+		node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-		gom.Expect(nodes.Items).NotTo(gom.BeEmpty())
+		framework.ExpectNoError(err)
-		response, err := grabber.GrabFromKubelet(nodes.Items[0].Name)
+		response, err := grabber.GrabFromKubelet(node.Name)
 		framework.ExpectNoError(err)
 		gom.Expect(response).NotTo(gom.BeEmpty())
 	})

test/e2e/lifecycle/kubelet_security.go

@@ -39,9 +39,9 @@ var _ = SIGDescribe("Ports Security Check [Feature:KubeletSecurity]", func() {
 	var nodeName string
 
 	ginkgo.BeforeEach(func() {
-		nodes := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+		var err error
-		gomega.Expect(len(nodes.Items)).NotTo(gomega.BeZero())
+		node, err = e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-		node = &nodes.Items[0]
+		framework.ExpectNoError(err)
 		nodeName = node.Name
 	})
 

test/e2e/network/proxy.go

@@ -33,6 +33,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/net"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/kubernetes/test/e2e/framework"
+	e2enode "k8s.io/kubernetes/test/e2e/framework/node"
 	testutils "k8s.io/kubernetes/test/utils"
 	imageutils "k8s.io/kubernetes/test/utils/image"
 
@@ -287,23 +288,16 @@ func truncate(b []byte, maxLen int) []byte {
 	return b2
 }
 
-func pickNode(cs clientset.Interface) (string, error) {
-	// TODO: investigate why it doesn't work on master Node.
-	nodes := framework.GetReadySchedulableNodesOrDie(cs)
-	if len(nodes.Items) == 0 {
-		return "", fmt.Errorf("no nodes exist, can't test node proxy")
-	}
-	return nodes.Items[0].Name, nil
-}
-
 func nodeProxyTest(f *framework.Framework, prefix, nodeDest string) {
-	node, err := pickNode(f.ClientSet)
+	// TODO: investigate why it doesn't work on master Node.
+	node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
 	framework.ExpectNoError(err)
+
 	// TODO: Change it to test whether all requests succeeded when requests
 	// not reaching Kubelet issue is debugged.
 	serviceUnavailableErrors := 0
 	for i := 0; i < proxyAttempts; i++ {
-		_, status, d, err := doProxy(f, prefix+node+nodeDest, i)
+		_, status, d, err := doProxy(f, prefix+node.Name+nodeDest, i)
 		if status == http.StatusServiceUnavailable {
 			framework.Logf("ginkgo.Failed proxying node logs due to service unavailable: %v", err)
 			time.Sleep(time.Second)

test/e2e/node/mount_propagation.go

@@ -23,6 +23,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/kubernetes/test/e2e/framework"
+	e2enode "k8s.io/kubernetes/test/e2e/framework/node"
 	e2essh "k8s.io/kubernetes/test/e2e/framework/ssh"
 	imageutils "k8s.io/kubernetes/test/utils/image"
 
@@ -85,9 +86,8 @@ var _ = SIGDescribe("Mount propagation", func() {
 		// propagated to the right places.
 
 		// Pick a node where all pods will run.
-		nodes := framework.GetReadySchedulableNodesOrDie(f.ClientSet)
+		node, err := e2enode.GetRandomReadySchedulableNode(f.ClientSet)
-		framework.ExpectNotEqual(len(nodes.Items), 0, "No available nodes for scheduling")
+		framework.ExpectNoError(err)
-		node := &nodes.Items[0]
 
 		// Fail the test if the namespace is not set. We expect that the
 		// namespace is unique and we might delete user data if it's not.
@@ -139,7 +139,7 @@ var _ = SIGDescribe("Mount propagation", func() {
 		// The host mounts one tmpfs to testdir/host and puts a file there so we
 		// can check mount propagation from the host to pods.
 		cmd := fmt.Sprintf("sudo mkdir %[1]q/host; sudo mount -t tmpfs e2e-mount-propagation-host %[1]q/host; echo host > %[1]q/host/file", hostDir)
-		err := e2essh.IssueSSHCommand(cmd, framework.TestContext.Provider, node)
+		err = e2essh.IssueSSHCommand(cmd, framework.TestContext.Provider, node)
 		framework.ExpectNoError(err)
 
 		defer func() {

test/e2e/scalability/load.go

@@ -59,6 +59,7 @@ import (
 	"k8s.io/kubernetes/pkg/apis/extensions"
 	"k8s.io/kubernetes/test/e2e/framework"
 	e2emetrics "k8s.io/kubernetes/test/e2e/framework/metrics"
+	e2enode "k8s.io/kubernetes/test/e2e/framework/node"
 	"k8s.io/kubernetes/test/e2e/framework/timer"
 	testutils "k8s.io/kubernetes/test/utils"
 
@@ -158,14 +159,14 @@ var _ = SIGDescribe("Load capacity", func() {
 		clientset = f.ClientSet
 
 		ns = f.Namespace.Name
-		nodes := framework.GetReadySchedulableNodesOrDie(clientset)
+
-		nodeCount = len(nodes.Items)
+		_, err := e2enode.GetRandomReadySchedulableNode(clientset)
-		gomega.Expect(nodeCount).NotTo(gomega.BeZero())
+		framework.ExpectNoError(err)
 
 		// Terminating a namespace (deleting the remaining objects from it - which
 		// generally means events) can affect the current run. Thus we wait for all
 		// terminating namespace to be finally deleted before starting this test.
-		err := framework.CheckTestingNSDeletedExcept(clientset, ns)
+		err = framework.CheckTestingNSDeletedExcept(clientset, ns)
 		framework.ExpectNoError(err)
 
 		framework.ExpectNoError(e2emetrics.ResetMetrics(clientset))