Golang Attributes.GetOperation方法代码示例

func (l *lifecycle) Admit(a admission.Attributes) (err error) {

	// prevent deletion of immortal namespaces
	if a.GetOperation() == admission.Delete && a.GetKind() == "Namespace" && l.immortalNamespaces.Has(a.GetName()) {
		return errors.NewForbidden(a.GetKind(), a.GetName(), fmt.Errorf("namespace can never be deleted"))
	}

	defaultVersion, kind, err := api.RESTMapper.VersionAndKindForResource(a.GetResource())
	if err != nil {
		return errors.NewInternalError(err)
	}
	mapping, err := api.RESTMapper.RESTMapping(kind, defaultVersion)
	if err != nil {
		return errors.NewInternalError(err)
	}
	if mapping.Scope.Name() != meta.RESTScopeNameNamespace {
		return nil
	}
	namespaceObj, exists, err := l.store.Get(&api.Namespace{
		ObjectMeta: api.ObjectMeta{
			Name:      a.GetNamespace(),
			Namespace: "",
		},
	})
	if err != nil {
		return errors.NewInternalError(err)
	}

	// refuse to operate on non-existent namespaces
	if !exists {
		// in case of latency in our caches, make a call direct to storage to verify that it truly exists or not
		namespaceObj, err = l.client.Namespaces().Get(a.GetNamespace())
		if err != nil {
			if errors.IsNotFound(err) {
				return err
			}
			return errors.NewInternalError(err)
		}
	}

	// ensure that we're not trying to create objects in terminating namespaces
	if a.GetOperation() == admission.Create {
		namespace := namespaceObj.(*api.Namespace)
		if namespace.Status.Phase != api.NamespaceTerminating {
			return nil
		}

		// TODO: This should probably not be a 403
		return admission.NewForbidden(a, fmt.Errorf("Unable to create new content in namespace %s because it is being terminated.", a.GetNamespace()))
	}

	return nil
}

func (q *quota) Admit(a admission.Attributes) (err error) {
	if a.GetSubresource() != "" {
		return nil
	}

	if a.GetOperation() == "DELETE" {
		return nil
	}

	key := &api.ResourceQuota{
		ObjectMeta: api.ObjectMeta{
			Namespace: a.GetNamespace(),
			Name:      "",
		},
	}

	// concurrent operations that modify quota tracked resources can cause a conflict when incrementing usage
	// as a result, we will attempt to increment quota usage per request up to numRetries limit
	// we fuzz each retry with an interval period to attempt to improve end-user experience during concurrent operations
	numRetries := 10
	interval := time.Duration(rand.Int63n(90)+int64(10)) * time.Millisecond

	items, err := q.indexer.Index("namespace", key)
	if err != nil {
		return admission.NewForbidden(a, fmt.Errorf("unable to %s %s at this time because there was an error enforcing quota", a.GetOperation(), a.GetResource()))
	}
	if len(items) == 0 {
		return nil
	}

	for i := range items {

		quota := items[i].(*api.ResourceQuota)

		for retry := 1; retry <= numRetries; retry++ {

			// we cannot modify the value directly in the cache, so we copy
			status := &api.ResourceQuotaStatus{
				Hard: api.ResourceList{},
				Used: api.ResourceList{},
			}
			for k, v := range quota.Status.Hard {
				status.Hard[k] = *v.Copy()
			}
			for k, v := range quota.Status.Used {
				status.Used[k] = *v.Copy()
			}

			dirty, err := IncrementUsage(a, status, q.client)
			if err != nil {
				return admission.NewForbidden(a, err)
			}

			if dirty {
				// construct a usage record
				usage := api.ResourceQuota{
					ObjectMeta: api.ObjectMeta{
						Name:            quota.Name,
						Namespace:       quota.Namespace,
						ResourceVersion: quota.ResourceVersion,
						Labels:          quota.Labels,
						Annotations:     quota.Annotations},
				}
				usage.Status = *status
				_, err = q.client.ResourceQuotas(usage.Namespace).UpdateStatus(&usage)
				if err == nil {
					break
				}

				// we have concurrent requests to update quota, so look to retry if needed
				if retry == numRetries {
					return admission.NewForbidden(a, fmt.Errorf("unable to %s %s at this time because there are too many concurrent requests to increment quota", a.GetOperation(), a.GetResource()))
				}
				time.Sleep(interval)
				// manually get the latest quota
				quota, err = q.client.ResourceQuotas(usage.Namespace).Get(quota.Name)
				if err != nil {
					return admission.NewForbidden(a, err)
				}
			}
		}
	}
	return nil
}

// IncrementUsage updates the supplied ResourceQuotaStatus object based on the incoming operation
// Return true if the usage must be recorded prior to admitting the new resource
// Return an error if the operation should not pass admission control
func IncrementUsage(a admission.Attributes, status *api.ResourceQuotaStatus, client client.Interface) (bool, error) {
	var errs []error
	dirty := true
	set := map[api.ResourceName]bool{}
	for k := range status.Hard {
		set[k] = true
	}
	obj := a.GetObject()
	// handle max counts for each kind of resource (pods, services, replicationControllers, etc.)
	if a.GetOperation() == admission.Create {
		resourceName := resourceToResourceName[a.GetResource()]
		hard, hardFound := status.Hard[resourceName]
		if hardFound {
			used, usedFound := status.Used[resourceName]
			if !usedFound {
				return false, fmt.Errorf("quota usage stats are not yet known, unable to admit resource until an accurate count is completed.")
			}
			if used.Value() >= hard.Value() {
				errs = append(errs, fmt.Errorf("limited to %s %s", hard.String(), resourceName))
				dirty = false
			} else {
				status.Used[resourceName] = *resource.NewQuantity(used.Value()+int64(1), resource.DecimalSI)
			}
		}
	}

	if a.GetResource() == "pods" {
		for _, resourceName := range []api.ResourceName{api.ResourceMemory, api.ResourceCPU} {

			// ignore tracking the resource if it's not in the quota document
			if !set[resourceName] {
				continue
			}

			hard, hardFound := status.Hard[resourceName]
			if !hardFound {
				continue
			}

			// if we do not yet know how much of the current resource is used, we cannot accept any request
			used, usedFound := status.Used[resourceName]
			if !usedFound {
				return false, fmt.Errorf("unable to admit pod until quota usage stats are calculated.")
			}

			// the amount of resource being requested, or an error if it does not make a request that is tracked
			pod := obj.(*api.Pod)
			delta, err := resourcequotacontroller.PodRequests(pod, resourceName)

			if err != nil {
				return false, fmt.Errorf("must make a non-zero request for %s since it is tracked by quota.", resourceName)
			}

			// if this operation is an update, we need to find the delta usage from the previous state
			if a.GetOperation() == admission.Update {
				oldPod, err := client.Pods(a.GetNamespace()).Get(pod.Name)
				if err != nil {
					return false, err
				}

				// if the previous version of the resource made a resource request, we need to subtract the old request
				// from the current to get the actual resource request delta.  if the previous version of the pod
				// made no request on the resource, then we get an err value.  we ignore the err value, and delta
				// will just be equal to the total resource request on the pod since there is nothing to subtract.
				oldRequest, err := resourcequotacontroller.PodRequests(oldPod, resourceName)
				if err == nil {
					err = delta.Sub(*oldRequest)
					if err != nil {
						return false, err
					}
				}
			}

			newUsage := used.Copy()
			newUsage.Add(*delta)

			// make the most precise comparison possible
			newUsageValue := newUsage.Value()
			hardUsageValue := hard.Value()
			if newUsageValue <= resource.MaxMilliValue && hardUsageValue <= resource.MaxMilliValue {
				newUsageValue = newUsage.MilliValue()
				hardUsageValue = hard.MilliValue()
			}

			if newUsageValue > hardUsageValue {
				errs = append(errs, fmt.Errorf("unable to admit pod without exceeding quota for resource %s:  limited to %s but require %s to succeed.", resourceName, hard.String(), newUsage.String()))
				dirty = false
			} else {
				status.Used[resourceName] = *newUsage
			}

		}
	}

	return dirty, errors.NewAggregate(errs)
}