Golang wait.Poll函數代碼示例

// Scale updates a deployment to a new size, with optional precondition check (if preconditions is not nil),
// optional retries (if retry is not nil), and then optionally waits for the status to reach desired count.
func (scaler *DeploymentScaler) Scale(namespace, name string, newSize uint, preconditions *ScalePrecondition, retry, waitForReplicas *RetryParams) error {
	if preconditions == nil {
		preconditions = &ScalePrecondition{-1, ""}
	}
	if retry == nil {
		// Make it try only once, immediately
		retry = &RetryParams{Interval: time.Millisecond, Timeout: time.Millisecond}
	}
	cond := ScaleCondition(scaler, preconditions, namespace, name, newSize, nil)
	if err := wait.Poll(retry.Interval, retry.Timeout, cond); err != nil {
		return err
	}
	if waitForReplicas != nil {
		deployment, err := scaler.c.Deployments(namespace).Get(name, metav1.GetOptions{})
		if err != nil {
			return err
		}
		err = wait.Poll(waitForReplicas.Interval, waitForReplicas.Timeout, client.DeploymentHasDesiredReplicas(scaler.c, deployment))
		if err == wait.ErrWaitTimeout {
			return fmt.Errorf("timed out waiting for %q to be synced", name)
		}
		return err
	}
	return nil
}

func checkTunnelsCorrect(t *testing.T, tunnelList *SSHTunnelList, addresses []string) {
	if err := wait.Poll(100*time.Millisecond, 2*time.Second, func() (bool, error) {
		return hasCorrectTunnels(tunnelList, addresses), nil
	}); err != nil {
		t.Errorf("Error waiting for tunnels to reach expected state: %v. Expected %v, had %v", err, addresses, tunnelList)
	}
}

func waitForReplicaSet(c *fedclientset.Clientset, namespace string, replicaSetName string, clusters map[string]*cluster) error {
	err := wait.Poll(10*time.Second, FederatedReplicaSetTimeout, func() (bool, error) {
		frs, err := c.ReplicaSets(namespace).Get(replicaSetName, metav1.GetOptions{})
		if err != nil {
			return false, err
		}
		specReplicas, statusReplicas := int32(0), int32(0)
		for _, cluster := range clusters {
			rs, err := cluster.ReplicaSets(namespace).Get(replicaSetName, metav1.GetOptions{})
			if err != nil && !errors.IsNotFound(err) {
				By(fmt.Sprintf("Failed getting replicaset: %q/%q/%q, err: %v", cluster.name, namespace, replicaSetName, err))
				return false, err
			}
			if err == nil {
				if !equivalentReplicaSet(frs, rs) {
					By(fmt.Sprintf("Replicaset meta or spec not match for cluster %q:\n    federation: %v\n    cluster: %v", cluster.name, frs, rs))
					return false, nil
				}
				specReplicas += *rs.Spec.Replicas
				statusReplicas += rs.Status.Replicas
			}
		}
		if statusReplicas == frs.Status.Replicas && specReplicas >= *frs.Spec.Replicas {
			return true, nil
		}
		By(fmt.Sprintf("Replicas not match, federation replicas: %v/%v, clusters replicas: %v/%v\n", *frs.Spec.Replicas, frs.Status.Replicas, specReplicas, statusReplicas))
		return false, nil
	})

	return err
}

// WaitForAttach runs on the node to detect if the volume (referenced by LUN) is attached. If attached, the device path is returned
func (attacher *azureDiskAttacher) WaitForAttach(spec *volume.Spec, lunStr string, timeout time.Duration) (string, error) {
	volumeSource, err := getVolumeSource(spec)
	if err != nil {
		return "", err
	}

	if len(lunStr) == 0 {
		return "", fmt.Errorf("WaitForAttach failed for Azure disk %q: lun is empty.", volumeSource.DiskName)
	}

	lun, err := strconv.Atoi(lunStr)
	if err != nil {
		return "", fmt.Errorf("WaitForAttach: wrong lun %q, err: %v", lunStr, err)
	}
	scsiHostRescan(&osIOHandler{})
	exe := exec.New()
	devicePath := ""

	err = wait.Poll(checkSleepDuration, timeout, func() (bool, error) {
		glog.V(4).Infof("Checking Azure disk %q(lun %s) is attached.", volumeSource.DiskName, lunStr)
		if devicePath, err = findDiskByLun(lun, &osIOHandler{}, exe); err == nil {
			glog.V(4).Infof("Successfully found attached Azure disk %q(lun %s, device path %s).", volumeSource.DiskName, lunStr, devicePath)
			return true, nil
		} else {
			//Log error, if any, and continue checking periodically
			glog.V(4).Infof("Error Stat Azure disk (%q) is attached: %v", volumeSource.DiskName, err)
			return false, nil
		}
	})
	return devicePath, err
}

// WaitForAuthorizationUpdate checks if the given user can perform the named verb and action.
// If policyCachePollTimeout is reached without the expected condition matching, an error is returned
func WaitForAuthorizationUpdate(c v1beta1authorization.SubjectAccessReviewsGetter, user, namespace, verb string, resource schema.GroupResource, allowed bool) error {
	review := &authorizationv1beta1.SubjectAccessReview{
		Spec: authorizationv1beta1.SubjectAccessReviewSpec{
			ResourceAttributes: &authorizationv1beta1.ResourceAttributes{
				Group:     resource.Group,
				Verb:      verb,
				Resource:  resource.Resource,
				Namespace: namespace,
			},
			User: user,
		},
	}
	err := wait.Poll(policyCachePollInterval, policyCachePollTimeout, func() (bool, error) {
		response, err := c.SubjectAccessReviews().Create(review)
		// GKE doesn't enable the SAR endpoint.  Without this endpoint, we cannot determine if the policy engine
		// has adjusted as expected.  In this case, simply wait one second and hope it's up to date
		if apierrors.IsNotFound(err) {
			fmt.Printf("SubjectAccessReview endpoint is missing\n")
			time.Sleep(1 * time.Second)
			return true, nil
		}
		if err != nil {
			return false, err
		}
		if response.Status.Allowed != allowed {
			return false, nil
		}
		return true, nil
	})
	return err
}

func TestMasterService(t *testing.T) {
	_, s := framework.RunAMaster(framework.NewIntegrationTestMasterConfig())
	defer s.Close()

	client := clientset.NewForConfigOrDie(&restclient.Config{Host: s.URL, ContentConfig: restclient.ContentConfig{GroupVersion: &api.Registry.GroupOrDie(api.GroupName).GroupVersion}})

	err := wait.Poll(time.Second, time.Minute, func() (bool, error) {
		svcList, err := client.Core().Services(api.NamespaceDefault).List(api.ListOptions{})
		if err != nil {
			t.Errorf("unexpected error: %v", err)
			return false, nil
		}
		found := false
		for i := range svcList.Items {
			if svcList.Items[i].Name == "kubernetes" {
				found = true
				break
			}
		}
		if found {
			ep, err := client.Core().Endpoints(api.NamespaceDefault).Get("kubernetes", metav1.GetOptions{})
			if err != nil {
				return false, nil
			}
			if countEndpoints(ep) == 0 {
				return false, fmt.Errorf("no endpoints for kubernetes service: %v", ep)
			}
			return true, nil
		}
		return false, nil
	})
	if err != nil {
		t.Errorf("unexpected error: %v", err)
	}
}

// Start starts resource collector and connects to the standalone Cadvisor pod
// then repeatedly runs collectStats.
func (r *ResourceCollector) Start() {
	// Get the cgroup container names for kubelet and docker
	kubeletContainer, err := getContainerNameForProcess(kubeletProcessName, "")
	dockerContainer, err := getContainerNameForProcess(dockerProcessName, dockerPidFile)
	if err == nil {
		systemContainers = map[string]string{
			stats.SystemContainerKubelet: kubeletContainer,
			stats.SystemContainerRuntime: dockerContainer,
		}
	} else {
		framework.Failf("Failed to get docker container name in test-e2e-node resource collector.")
	}

	wait.Poll(1*time.Second, 1*time.Minute, func() (bool, error) {
		var err error
		r.client, err = cadvisorclient.NewClient(fmt.Sprintf("http://localhost:%d/", cadvisorPort))
		if err == nil {
			return true, nil
		}
		return false, err
	})

	Expect(r.client).NotTo(BeNil(), "cadvisor client not ready")

	r.request = &cadvisorapiv2.RequestOptions{IdType: "name", Count: 1, Recursive: false}
	r.stopCh = make(chan struct{})

	oldStatsMap := make(map[string]*cadvisorapiv2.ContainerStats)
	go wait.Until(func() { r.collectStats(oldStatsMap) }, r.pollingInterval, r.stopCh)
}

func waitForDeployment(c *fedclientset.Clientset, namespace string, deploymentName string, clusters map[string]*cluster) error {
	err := wait.Poll(10*time.Second, FederatedDeploymentTimeout, func() (bool, error) {
		fdep, err := c.Deployments(namespace).Get(deploymentName, metav1.GetOptions{})
		if err != nil {
			return false, err
		}
		specReplicas, statusReplicas := int32(0), int32(0)
		for _, cluster := range clusters {
			dep, err := cluster.Deployments(namespace).Get(deploymentName, metav1.GetOptions{})
			if err != nil && !errors.IsNotFound(err) {
				By(fmt.Sprintf("Failed getting deployment: %q/%q/%q, err: %v", cluster.name, namespace, deploymentName, err))
				return false, err
			}
			if err == nil {
				if !verifyDeployment(fdep, dep) {
					By(fmt.Sprintf("Deployment meta or spec not match for cluster %q:\n    federation: %v\n    cluster: %v", cluster.name, fdep, dep))
					return false, nil
				}
				specReplicas += *dep.Spec.Replicas
				statusReplicas += dep.Status.Replicas
			}
		}
		if statusReplicas == fdep.Status.Replicas && specReplicas >= *fdep.Spec.Replicas {
			return true, nil
		}
		By(fmt.Sprintf("Replicas not match, federation replicas: %v/%v, clusters replicas: %v/%v\n", *fdep.Spec.Replicas, fdep.Status.Replicas, specReplicas, statusReplicas))
		return false, nil
	})

	return err
}

func Rename(c coreclient.ReplicationControllersGetter, rc *api.ReplicationController, newName string) error {
	oldName := rc.Name
	rc.Name = newName
	rc.ResourceVersion = ""
	// First delete the oldName RC and orphan its pods.
	trueVar := true
	err := c.ReplicationControllers(rc.Namespace).Delete(oldName, &api.DeleteOptions{OrphanDependents: &trueVar})
	if err != nil && !errors.IsNotFound(err) {
		return err
	}
	err = wait.Poll(5*time.Second, 60*time.Second, func() (bool, error) {
		_, err := c.ReplicationControllers(rc.Namespace).Get(oldName, metav1.GetOptions{})
		if err == nil {
			return false, nil
		} else if errors.IsNotFound(err) {
			return true, nil
		} else {
			return false, err
		}
	})
	if err != nil {
		return err
	}
	// Then create the same RC with the new name.
	_, err = c.ReplicationControllers(rc.Namespace).Create(rc)
	if err != nil {
		return err
	}
	return nil
}

func (reaper *DaemonSetReaper) Stop(namespace, name string, timeout time.Duration, gracePeriod *api.DeleteOptions) error {
	ds, err := reaper.client.DaemonSets(namespace).Get(name, metav1.GetOptions{})
	if err != nil {
		return err
	}

	// We set the nodeSelector to a random label. This label is nearly guaranteed
	// to not be set on any node so the DameonSetController will start deleting
	// daemon pods. Once it's done deleting the daemon pods, it's safe to delete
	// the DaemonSet.
	ds.Spec.Template.Spec.NodeSelector = map[string]string{
		string(uuid.NewUUID()): string(uuid.NewUUID()),
	}
	// force update to avoid version conflict
	ds.ResourceVersion = ""

	if ds, err = reaper.client.DaemonSets(namespace).Update(ds); err != nil {
		return err
	}

	// Wait for the daemon set controller to kill all the daemon pods.
	if err := wait.Poll(reaper.pollInterval, reaper.timeout, func() (bool, error) {
		updatedDS, err := reaper.client.DaemonSets(namespace).Get(name, metav1.GetOptions{})
		if err != nil {
			return false, nil
		}

		return updatedDS.Status.CurrentNumberScheduled+updatedDS.Status.NumberMisscheduled == 0, nil
	}); err != nil {
		return err
	}

	return reaper.client.DaemonSets(namespace).Delete(name, nil)
}

// waitForNPods tries to list pods using c until it finds expect of them,
// returning their names if it can do so before timeout.
func waitForNPods(ps *testutils.PodStore, expect int, timeout time.Duration) ([]string, error) {
	// Loop until we find expect pods or timeout is passed.
	var pods []*v1.Pod
	var errLast error
	found := wait.Poll(framework.Poll, timeout, func() (bool, error) {
		allPods := ps.List()
		pods := filterIrrelevantPods(allPods)
		if len(pods) != expect {
			errLast = fmt.Errorf("expected to find %d pods but found only %d", expect, len(pods))
			framework.Logf("Error getting pods: %v", errLast)
			return false, nil
		}
		return true, nil
	}) == nil
	// Extract the names of all found pods.
	podNames := make([]string, len(pods))
	for i, p := range pods {
		podNames[i] = p.ObjectMeta.Name
	}
	if !found {
		return podNames, fmt.Errorf("couldn't find %d pods within %v; last error: %v",
			expect, timeout, errLast)
	}
	return podNames, nil
}

// WaitFor waits for some minimum number of pods to be verified, according to the PodStateVerification
// definition.
func (cl *ClusterVerification) WaitFor(atLeast int, timeout time.Duration) ([]v1.Pod, error) {
	pods := []v1.Pod{}
	var returnedErr error

	err := wait.Poll(1*time.Second, timeout, func() (bool, error) {
		pods, returnedErr = cl.podState.filter(cl.client, cl.namespace)

		// Failure
		if returnedErr != nil {
			Logf("Cutting polling short: We got an error from the pod filtering layer.")
			// stop polling if the pod filtering returns an error.  that should never happen.
			// it indicates, for example, that the client is broken or something non-pod related.
			return false, returnedErr
		}
		Logf("Found %v / %v", len(pods), atLeast)

		// Success
		if len(pods) >= atLeast {
			return true, nil
		}
		// Keep trying...
		return false, nil
	})
	Logf("WaitFor completed with timeout %v.  Pods found = %v out of %v", timeout, len(pods), atLeast)
	return pods, err
}

// Wait till the passFunc confirms that the object it expects to see is in the store.
// Used to observe reflected events.
func waitForReflection(t *testing.T, s cache.Store, key string, passFunc func(n interface{}) bool) error {
	nodes := []*v1.Node{}
	err := wait.Poll(time.Millisecond*100, wait.ForeverTestTimeout, func() (bool, error) {
		if n, _, err := s.GetByKey(key); err == nil && passFunc(n) {
			return true, nil
		} else {
			if err != nil {
				t.Errorf("Unexpected error: %v", err)
			} else {
				if n == nil {
					nodes = append(nodes, nil)
				} else {
					nodes = append(nodes, n.(*v1.Node))
				}
			}
			return false, nil
		}
	})
	if err != nil {
		t.Logf("Logging consecutive node versions received from store:")
		for i, n := range nodes {
			t.Logf("%d: %#v", i, n)
		}
	}
	return err
}

// MigTemplate (GCE-only) returns the name of the MIG template that the
// nodes of the cluster use.
func MigTemplate() (string, error) {
	var errLast error
	var templ string
	key := "instanceTemplate"
	if wait.Poll(Poll, SingleCallTimeout, func() (bool, error) {
		// TODO(mikedanese): make this hit the compute API directly instead of
		// shelling out to gcloud.
		// An `instance-groups managed describe` call outputs what we want to stdout.
		output, _, err := retryCmd("gcloud", "compute", "instance-groups", "managed",
			fmt.Sprintf("--project=%s", TestContext.CloudConfig.ProjectID),
			"describe",
			fmt.Sprintf("--zone=%s", TestContext.CloudConfig.Zone),
			TestContext.CloudConfig.NodeInstanceGroup)
		if err != nil {
			errLast = fmt.Errorf("gcloud compute instance-groups managed describe call failed with err: %v", err)
			return false, nil
		}

		// The 'describe' call probably succeeded; parse the output and try to
		// find the line that looks like "instanceTemplate: url/to/<templ>" and
		// return <templ>.
		if val := ParseKVLines(output, key); len(val) > 0 {
			url := strings.Split(val, "/")
			templ = url[len(url)-1]
			Logf("MIG group %s using template: %s", TestContext.CloudConfig.NodeInstanceGroup, templ)
			return true, nil
		}
		errLast = fmt.Errorf("couldn't find %s in output to get MIG template. Output: %s", key, output)
		return false, nil
	}) != nil {
		return "", fmt.Errorf("MigTemplate() failed with last error: %v", errLast)
	}
	return templ, nil
}

func waitForUpdatedNodeWithTimeout(nodeHandler *testutil.FakeNodeHandler, number int, timeout time.Duration) error {
	return wait.Poll(nodePollInterval, timeout, func() (bool, error) {
		if len(nodeHandler.GetUpdatedNodesCopy()) >= number {
			return true, nil
		}
		return false, nil
	})
}