Merge pull request #67406 from freehan/pod-ready

Automatic merge from submit-queue (batch tested with PRs 67031, 67406). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Pod Ready++ cont

```release-note
Turn on PodReadinessGate by default
```

ref: https://github.com/kubernetes/community/blob/master/keps/sig-network/0007-pod-ready%2B%2B.md

pkg/features/kube_features.go

@@ -397,7 +397,7 @@ var defaultKubernetesFeatureGates = map[utilfeature.Feature]utilfeature.FeatureS
 	VolumeSubpath:                               {Default: true, PreRelease: utilfeature.GA},
 	BalanceAttachedNodeVolumes:                  {Default: false, PreRelease: utilfeature.Alpha},
 	DynamicProvisioningScheduling:               {Default: false, PreRelease: utilfeature.Alpha},
-	PodReadinessGates:                           {Default: false, PreRelease: utilfeature.Beta},
+	PodReadinessGates:                           {Default: true, PreRelease: utilfeature.Beta},
 	VolumeSubpathEnvExpansion:                   {Default: false, PreRelease: utilfeature.Alpha},
 	KubeletPluginsWatcher:                       {Default: false, PreRelease: utilfeature.Alpha},
 	ResourceQuotaScopeSelectors:                 {Default: true, PreRelease: utilfeature.Beta},

test/e2e/common/BUILD

@@ -52,6 +52,7 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/labels:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/types:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/intstr:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/uuid:go_default_library",

test/e2e/common/pods.go

@@ -39,6 +39,7 @@ import (
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
+	"k8s.io/apimachinery/pkg/types"
 	imageutils "k8s.io/kubernetes/test/utils/image"
 )
 
@@ -46,6 +47,10 @@ var (
 	buildBackOffDuration = time.Minute
 	syncLoopFrequency    = 10 * time.Second
 	maxBackOffTolerance  = time.Duration(1.3 * float64(kubelet.MaxContainerBackOff))
+	// maxReadyStatusUpdateTolerance specifies the latency that allows kubelet to update pod status.
+	// When kubelet is under heavy load (tests may be parallelized), the delay may be longer, hence
+	// causing tests to be flaky.
+	maxReadyStatusUpdateTolerance = 10 * time.Second
 )
 
 // testHostIP tests that a pod gets a host IP
@@ -694,4 +699,64 @@ var _ = framework.KubeDescribe("Pods", func() {
 			framework.Failf("expected %s back-off got=%s on delay2", kubelet.MaxContainerBackOff, delay2)
 		}
 	})
+
+	// TODO(freehan): label the test to be [NodeConformance] after tests are proven to be stable.
+	It("should support pod readiness gates [NodeFeature:PodReadinessGate]", func() {
+		podName := "pod-ready"
+		readinessGate1 := "k8s.io/test-condition1"
+		readinessGate2 := "k8s.io/test-condition2"
+		patchStatusFmt := `{"status":{"conditions":[{"type":%q, "status":%q}]}}`
+		pod := &v1.Pod{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:   podName,
+				Labels: map[string]string{"test": "pod-readiness-gate"},
+			},
+			Spec: v1.PodSpec{
+				Containers: []v1.Container{
+					{
+						Name:    "pod-readiness-gate",
+						Image:   imageutils.GetE2EImage(imageutils.BusyBox),
+						Command: []string{"/bin/sh", "-c", "echo container is alive; sleep 10000"},
+					},
+				},
+				ReadinessGates: []v1.PodReadinessGate{
+					{ConditionType: v1.PodConditionType(readinessGate1)},
+					{ConditionType: v1.PodConditionType(readinessGate2)},
+				},
+			},
+		}
+
+		validatePodReadiness := func(expectReady bool) {
+			Expect(wait.Poll(time.Second, maxReadyStatusUpdateTolerance, func() (bool, error) {
+				podReady := podClient.PodIsReady(podName)
+				res := expectReady == podReady
+				if !res {
+					framework.Logf("Expect the Ready condition of pod %q to be %v, but got %v", podName, expectReady, podReady)
+				}
+				return res, nil
+			})).NotTo(HaveOccurred())
+		}
+
+		By("submitting the pod to kubernetes")
+		podClient.CreateSync(pod)
+		Expect(podClient.PodIsReady(podName)).To(BeFalse(), "Expect pod's Ready condition to be false initially.")
+
+		By(fmt.Sprintf("patching pod status with condition %q to true", readinessGate1))
+		_, err := podClient.Patch(podName, types.StrategicMergePatchType, []byte(fmt.Sprintf(patchStatusFmt, readinessGate1, "True")), "status")
+		Expect(err).NotTo(HaveOccurred())
+		// Sleep for 10 seconds.
+		time.Sleep(maxReadyStatusUpdateTolerance)
+		Expect(podClient.PodIsReady(podName)).To(BeFalse(), "Expect pod's Ready condition to be false with only one condition in readinessGates equal to True")
+
+		By(fmt.Sprintf("patching pod status with condition %q to true", readinessGate2))
+		_, err = podClient.Patch(podName, types.StrategicMergePatchType, []byte(fmt.Sprintf(patchStatusFmt, readinessGate2, "True")), "status")
+		Expect(err).NotTo(HaveOccurred())
+		validatePodReadiness(true)
+
+		By(fmt.Sprintf("patching pod status with condition %q to false", readinessGate1))
+		_, err = podClient.Patch(podName, types.StrategicMergePatchType, []byte(fmt.Sprintf(patchStatusFmt, readinessGate1, "False")), "status")
+		Expect(err).NotTo(HaveOccurred())
+		validatePodReadiness(false)
+
+	})
 })

test/e2e/framework/pods.go

@@ -30,6 +30,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/wait"
 	v1core "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/kubernetes/pkg/api/legacyscheme"
+	podutil "k8s.io/kubernetes/pkg/api/v1/pod"
 	"k8s.io/kubernetes/pkg/kubelet/events"
 	"k8s.io/kubernetes/pkg/kubelet/sysctl"
 
@@ -259,3 +260,9 @@ func (c *PodClient) MatchContainerOutput(name string, containerName string, expe
 	}
 	return nil
 }
+
+func (c *PodClient) PodIsReady(name string) bool {
+	pod, err := c.Get(name, metav1.GetOptions{})
+	ExpectNoError(err)
+	return podutil.IsPodReady(pod)
+}