Golang deployment.GetAvailablePodsForRCs函数代码示例

// cleanupUnhealthyReplicas will scale down old rcs with unhealthy replicas, so that all unhealthy replicas will be deleted.
func (dc *DeploymentController) cleanupUnhealthyReplicas(oldRCs []*api.ReplicationController, deployment extensions.Deployment, maxCleanupCount int) (int, error) {
	sort.Sort(controller.ControllersByCreationTimestamp(oldRCs))
	// Safely scale down all old rcs with unhealthy replicas. ReplicationController/ReplicaSet will sort the pods in the order
	// such that not-ready < ready, unscheduled < scheduled, and pending < running. This ensures that unhealthy replicas will
	// been deleted first and won't increase unavailability.
	totalScaledDown := 0
	for _, targetRC := range oldRCs {
		if totalScaledDown >= maxCleanupCount {
			break
		}
		if targetRC.Spec.Replicas == 0 {
			// cannot scale down this RC.
			continue
		}
		readyPodCount, err := deploymentutil.GetAvailablePodsForRCs(dc.client, []*api.ReplicationController{targetRC}, 0)
		if err != nil {
			return totalScaledDown, fmt.Errorf("could not find available pods: %v", err)
		}
		if targetRC.Spec.Replicas == readyPodCount {
			// no unhealthy replicas found, no scaling required.
			continue
		}

		scaledDownCount := int(math.Min(float64(maxCleanupCount-totalScaledDown), float64(targetRC.Spec.Replicas-readyPodCount)))
		newReplicasCount := targetRC.Spec.Replicas - scaledDownCount
		_, err = dc.scaleRCAndRecordEvent(targetRC, newReplicasCount, deployment)
		if err != nil {
			return totalScaledDown, err
		}
		totalScaledDown += scaledDownCount
	}
	return totalScaledDown, nil
}

func (dc *DeploymentController) calculateStatus(allRCs []*api.ReplicationController, newRC *api.ReplicationController, deployment extensions.Deployment) (totalReplicas, updatedReplicas, availableReplicas, unavailableReplicas int, err error) {
	totalReplicas = deploymentutil.GetReplicaCountForRCs(allRCs)
	updatedReplicas = deploymentutil.GetReplicaCountForRCs([]*api.ReplicationController{newRC})
	minReadySeconds := deployment.Spec.MinReadySeconds
	availableReplicas, err = deploymentutil.GetAvailablePodsForRCs(dc.client, allRCs, minReadySeconds)
	if err != nil {
		err = fmt.Errorf("failed to count available pods: %v", err)
		return
	}
	unavailableReplicas = totalReplicas - availableReplicas
	return
}

// syncDeploymentStatus checks if the status is up-to-date and sync it if necessary
func (dc *DeploymentController) syncDeploymentStatus(allRCs []*api.ReplicationController, newRC *api.ReplicationController, deployment extensions.Deployment) error {
	totalReplicas := deploymentutil.GetReplicaCountForRCs(allRCs)
	updatedReplicas := deploymentutil.GetReplicaCountForRCs([]*api.ReplicationController{newRC})
	availablePods, err := deploymentutil.GetAvailablePodsForRCs(dc.client, allRCs, deployment.Spec.Strategy.RollingUpdate.MinReadySeconds)
	if err != nil {
		return fmt.Errorf("failed to count ready pods: %v", err)
	}
	if deployment.Status.Replicas != totalReplicas || deployment.Status.UpdatedReplicas != updatedReplicas || deployment.Status.AvailableReplicas != availablePods {
		return dc.updateDeploymentStatus(allRCs, newRC, deployment)
	}
	return nil
}

func (d *DeploymentController) reconcileOldRCs(allRCs []*api.ReplicationController, oldRCs []*api.ReplicationController, newRC *api.ReplicationController, deployment extensions.Deployment) (bool, error) {
	oldPodsCount := deploymentutil.GetReplicaCountForRCs(oldRCs)
	if oldPodsCount == 0 {
		// Cant scale down further
		return false, nil
	}
	maxUnavailable, isPercent, err := util.GetIntOrPercentValue(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable)
	if err != nil {
		return false, fmt.Errorf("invalid value for MaxUnavailable: %v", err)
	}
	if isPercent {
		maxUnavailable = util.GetValueFromPercent(maxUnavailable, deployment.Spec.Replicas)
	}
	// Check if we can scale down.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	minReadySeconds := deployment.Spec.Strategy.RollingUpdate.MinReadySeconds
	// Find the number of ready pods.
	readyPodCount, err := deploymentutil.GetAvailablePodsForRCs(d.client, allRCs, minReadySeconds)
	if err != nil {
		return false, fmt.Errorf("could not find available pods: %v", err)
	}

	if readyPodCount <= minAvailable {
		// Cannot scale down.
		return false, nil
	}
	totalScaleDownCount := readyPodCount - minAvailable
	for _, targetRC := range oldRCs {
		if totalScaleDownCount == 0 {
			// No further scaling required.
			break
		}
		if targetRC.Spec.Replicas == 0 {
			// cannot scale down this RC.
			continue
		}
		// Scale down.
		scaleDownCount := int(math.Min(float64(targetRC.Spec.Replicas), float64(totalScaleDownCount)))
		newReplicasCount := targetRC.Spec.Replicas - scaleDownCount
		_, err = d.scaleRCAndRecordEvent(targetRC, newReplicasCount, deployment)
		if err != nil {
			return false, err
		}
		totalScaleDownCount -= scaleDownCount
	}
	return true, err
}

// scaleDownOldRCsForRollingUpdate scales down old rcs when deployment strategy is "RollingUpdate".
// Need check maxUnavailable to ensure availability
func (dc *DeploymentController) scaleDownOldRCsForRollingUpdate(allRCs []*api.ReplicationController, oldRCs []*api.ReplicationController, deployment extensions.Deployment) (int, error) {
	maxUnavailable, isPercent, err := util.GetIntOrPercentValue(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable)
	if err != nil {
		return 0, fmt.Errorf("invalid value for MaxUnavailable: %v", err)
	}
	if isPercent {
		maxUnavailable = util.GetValueFromPercent(maxUnavailable, deployment.Spec.Replicas)
	}
	// Check if we can scale down.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	minReadySeconds := deployment.Spec.MinReadySeconds
	// Find the number of ready pods.
	readyPodCount, err := deploymentutil.GetAvailablePodsForRCs(dc.client, allRCs, minReadySeconds)
	if err != nil {
		return 0, fmt.Errorf("could not find available pods: %v", err)
	}
	if readyPodCount <= minAvailable {
		// Cannot scale down.
		return 0, nil
	}

	sort.Sort(controller.ControllersByCreationTimestamp(oldRCs))

	totalScaledDown := 0
	totalScaleDownCount := readyPodCount - minAvailable
	for _, targetRC := range oldRCs {
		if totalScaledDown >= totalScaleDownCount {
			// No further scaling required.
			break
		}
		if targetRC.Spec.Replicas == 0 {
			// cannot scale down this RC.
			continue
		}
		// Scale down.
		scaleDownCount := int(math.Min(float64(targetRC.Spec.Replicas), float64(totalScaleDownCount-totalScaledDown)))
		newReplicasCount := targetRC.Spec.Replicas - scaleDownCount
		_, err = dc.scaleRCAndRecordEvent(targetRC, newReplicasCount, deployment)
		if err != nil {
			return totalScaledDown, err
		}

		totalScaledDown += scaleDownCount
	}

	return totalScaledDown, nil
}

func (dc *DeploymentController) updateDeploymentStatus(allRCs []*api.ReplicationController, newRC *api.ReplicationController, deployment extensions.Deployment) error {
	totalReplicas := deploymentutil.GetReplicaCountForRCs(allRCs)
	updatedReplicas := deploymentutil.GetReplicaCountForRCs([]*api.ReplicationController{newRC})
	availablePods, err := deploymentutil.GetAvailablePodsForRCs(dc.client, allRCs, deployment.Spec.Strategy.RollingUpdate.MinReadySeconds)
	if err != nil {
		return fmt.Errorf("failed to count ready pods: %v", err)
	}
	newDeployment := deployment
	// TODO: Reconcile this with API definition. API definition talks about ready pods, while this just computes created pods.
	newDeployment.Status = extensions.DeploymentStatus{
		Replicas:            totalReplicas,
		UpdatedReplicas:     updatedReplicas,
		AvailableReplicas:   availablePods,
		UnavailableReplicas: totalReplicas - availablePods,
	}
	_, err = dc.expClient.Deployments(deployment.ObjectMeta.Namespace).UpdateStatus(&newDeployment)
	return err
}

// Set expectationsCheck to false to bypass expectations check when testing
func (dc *DeploymentController) reconcileOldRCs(allRCs []*api.ReplicationController, oldRCs []*api.ReplicationController, newRC *api.ReplicationController, deployment extensions.Deployment, expectationsCheck bool) (bool, error) {
	oldPodsCount := deploymentutil.GetReplicaCountForRCs(oldRCs)
	if oldPodsCount == 0 {
		// Cant scale down further
		return false, nil
	}
	maxUnavailable, isPercent, err := util.GetIntOrPercentValue(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable)
	if err != nil {
		return false, fmt.Errorf("invalid value for MaxUnavailable: %v", err)
	}
	if isPercent {
		maxUnavailable = util.GetValueFromPercent(maxUnavailable, deployment.Spec.Replicas)
	}
	// Check if we can scale down.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	minReadySeconds := deployment.Spec.Strategy.RollingUpdate.MinReadySeconds
	// Check the expectations of deployment before counting available pods
	dKey, err := controller.KeyFunc(&deployment)
	if err != nil {
		return false, fmt.Errorf("Couldn't get key for deployment %#v: %v", deployment, err)
	}
	if expectationsCheck && !dc.podExpectations.SatisfiedExpectations(dKey) {
		glog.V(4).Infof("Pod expectations not met yet before reconciling old RCs\n")
		return false, nil
	}
	// Find the number of ready pods.
	readyPodCount, err := deploymentutil.GetAvailablePodsForRCs(dc.client, allRCs, minReadySeconds)
	if err != nil {
		return false, fmt.Errorf("could not find available pods: %v", err)
	}

	if readyPodCount <= minAvailable {
		// Cannot scale down.
		return false, nil
	}
	totalScaleDownCount := readyPodCount - minAvailable
	totalScaledDown := 0
	for _, targetRC := range oldRCs {
		if totalScaleDownCount == 0 {
			// No further scaling required.
			break
		}
		if targetRC.Spec.Replicas == 0 {
			// cannot scale down this RC.
			continue
		}
		// Scale down.
		scaleDownCount := int(math.Min(float64(targetRC.Spec.Replicas), float64(totalScaleDownCount)))
		newReplicasCount := targetRC.Spec.Replicas - scaleDownCount
		_, err = dc.scaleRCAndRecordEvent(targetRC, newReplicasCount, deployment)
		if err != nil {
			return false, err
		}
		totalScaledDown += scaleDownCount
		totalScaleDownCount -= scaleDownCount
	}
	// Expect to see old rcs scaled down by exactly totalScaledDownCount (sum of scaleDownCount) replicas.
	dKey, err = controller.KeyFunc(&deployment)
	if err != nil {
		return false, fmt.Errorf("Couldn't get key for deployment %#v: %v", deployment, err)
	}
	if expectationsCheck {
		dc.podExpectations.ExpectDeletions(dKey, totalScaledDown)
	}
	return true, err
}

// Set expectationsCheck to false to bypass expectations check when testing
func (dc *DeploymentController) reconcileOldRCs(allRCs []*api.ReplicationController, oldRCs []*api.ReplicationController, newRC *api.ReplicationController, deployment extensions.Deployment, expectationsCheck bool) (bool, error) {
	oldPodsCount := deploymentutil.GetReplicaCountForRCs(oldRCs)
	if oldPodsCount == 0 {
		// Can't scale down further
		return false, nil
	}

	// Check the expectations of deployment before reconciling
	dKey, err := controller.KeyFunc(&deployment)
	if err != nil {
		return false, fmt.Errorf("Couldn't get key for deployment %#v: %v", deployment, err)
	}
	if expectationsCheck && !dc.podExpectations.SatisfiedExpectations(dKey) {
		glog.V(4).Infof("Pod expectations not met yet before reconciling old RCs\n")
		return false, nil
	}

	minReadySeconds := deployment.Spec.MinReadySeconds
	allPodsCount := deploymentutil.GetReplicaCountForRCs(allRCs)
	newRCAvailablePodCount, err := deploymentutil.GetAvailablePodsForRCs(dc.client, []*api.ReplicationController{newRC}, minReadySeconds)
	if err != nil {
		return false, fmt.Errorf("could not find available pods: %v", err)
	}

	maxUnavailable, isPercent, err := util.GetIntOrPercentValue(&deployment.Spec.Strategy.RollingUpdate.MaxUnavailable)
	if err != nil {
		return false, fmt.Errorf("invalid value for MaxUnavailable: %v", err)
	}
	if isPercent {
		maxUnavailable = util.GetValueFromPercent(maxUnavailable, deployment.Spec.Replicas)
	}

	// Check if we can scale down. We can scale down in the following 2 cases:
	// * Some old rcs have unhealthy replicas, we could safely scale down those unhealthy replicas since that won't further
	//  increase unavailability.
	// * New rc has scaled up and it's replicas becomes ready, then we can scale down old rcs in a further step.
	//
	// maxScaledDown := allPodsCount - minAvailable - newRCPodsUnavailable
	// take into account not only maxUnavailable and any surge pods that have been created, but also unavailable pods from
	// the newRC, so that the unavailable pods from the newRC would not make us scale down old RCs in a further step(that will
	// increase unavailability).
	//
	// Concrete example:
	//
	// * 10 replicas
	// * 2 maxUnavailable (absolute number, not percent)
	// * 3 maxSurge (absolute number, not percent)
	//
	// case 1:
	// * Deployment is updated, newRC is created with 3 replicas, oldRC is scaled down to 8, and newRC is scaled up to 5.
	// * The new RC pods crashloop and never become available.
	// * allPodsCount is 13. minAvailable is 8. newRCPodsUnavailable is 5.
	// * A node fails and causes one of the oldRC pods to become unavailable. However, 13 - 8 - 5 = 0, so the oldRC won't be scaled down.
	// * The user notices the crashloop and does kubectl rollout undo to rollback.
	// * newRCPodsUnavailable is 1, since we rolled back to the good RC, so maxScaledDown = 13 - 8 - 1 = 4. 4 of the crashlooping pods will be scaled down.
	// * The total number of pods will then be 9 and the newRC can be scaled up to 10.
	//
	// case 2:
	// Same example, but pushing a new pod template instead of rolling back (aka "roll over"):
	// * The new RC created must start with 0 replicas because allPodsCount is already at 13.
	// * However, newRCPodsUnavailable would also be 0, so the 2 old RCs could be scaled down by 5 (13 - 8 - 0), which would then
	// allow the new RC to be scaled up by 5.
	minAvailable := deployment.Spec.Replicas - maxUnavailable
	newRCUnavailablePodCount := newRC.Spec.Replicas - newRCAvailablePodCount
	maxScaledDown := allPodsCount - minAvailable - newRCUnavailablePodCount
	if maxScaledDown <= 0 {
		return false, nil
	}

	// Clean up unhealthy replicas first, otherwise unhealthy replicas will block deployment
	// and cause timeout. See https://github.com/kubernetes/kubernetes/issues/16737
	cleanupCount, err := dc.cleanupUnhealthyReplicas(oldRCs, deployment, maxScaledDown)
	if err != nil {
		return false, nil
	}

	// Scale down old rcs, need check maxUnavailable to ensure we can scale down
	scaledDownCount, err := dc.scaleDownOldRCsForRollingUpdate(allRCs, oldRCs, deployment)
	if err != nil {
		return false, nil
	}

	totalScaledDown := cleanupCount + scaledDownCount
	if expectationsCheck {
		dc.podExpectations.ExpectDeletions(dKey, totalScaledDown)
	}

	return totalScaledDown > 0, nil
}