Golang meta.ListAccessor函数代码示例

// UsageStats calculates latest observed usage stats for all objects
func (g *GenericEvaluator) UsageStats(options quota.UsageStatsOptions) (quota.UsageStats, error) {
	// default each tracked resource to zero
	result := quota.UsageStats{Used: api.ResourceList{}}
	for _, resourceName := range g.MatchedResourceNames {
		result.Used[resourceName] = resource.MustParse("0")
	}
	list, err := g.ListFuncByNamespace(options.Namespace, api.ListOptions{})
	if err != nil {
		return result, fmt.Errorf("%s: Failed to list %v: %v", g.Name, g.GroupKind(), err)
	}
	_, err = meta.ListAccessor(list)
	if err != nil {
		return result, fmt.Errorf("%s: Unable to understand list result, does not appear to be a list %#v", g.Name, list)
	}
	items, err := meta.ExtractList(list)
	if err != nil {
		return result, fmt.Errorf("%s: Unable to understand list result %#v (%v)", g.Name, list, err)
	}
	for _, item := range items {
		// need to verify that the item matches the set of scopes
		matchesScopes := true
		for _, scope := range options.Scopes {
			if !g.MatchesScope(scope, item) {
				matchesScopes = false
			}
		}
		// only count usage if there was a match
		if matchesScopes {
			result.Used = quota.Add(result.Used, g.Usage(item))
		}
	}
	return result, nil
}

// ListAndWatch first lists all items and get the resource version at the moment of call,
// and then use the resource version to watch.
// It returns error if ListAndWatch didn't even try to initialize watch.
func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
	glog.V(3).Infof("Listing and watching %v from %s", r.expectedType, r.name)
	var resourceVersion string
	resyncCh, cleanup := r.resyncChan()
	defer cleanup()

	// Explicitly set "0" as resource version - it's fine for the List()
	// to be served from cache and potentially be delayed relative to
	// etcd contents. Reflector framework will catch up via Watch() eventually.
	options := api.ListOptions{ResourceVersion: "0"}
	list, err := r.listerWatcher.List(options)
	if err != nil {
		return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err)
	}
	listMetaInterface, err := meta.ListAccessor(list)
	if err != nil {
		return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err)
	}
	resourceVersion = listMetaInterface.GetResourceVersion()
	items, err := meta.ExtractList(list)
	if err != nil {
		return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err)
	}
	if err := r.syncWith(items, resourceVersion); err != nil {
		return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err)
	}
	r.setLastSyncResourceVersion(resourceVersion)

	for {
		options := api.ListOptions{
			ResourceVersion: resourceVersion,
			// We want to avoid situations when resyncing is breaking the TCP connection
			// - see comment for 'timeoutForWatch()' for more details.
			TimeoutSeconds: r.timeoutForWatch(),
		}
		w, err := r.listerWatcher.Watch(options)
		if err != nil {
			switch err {
			case io.EOF:
				// watch closed normally
			case io.ErrUnexpectedEOF:
				glog.V(1).Infof("%s: Watch for %v closed with unexpected EOF: %v", r.name, r.expectedType, err)
			default:
				utilruntime.HandleError(fmt.Errorf("%s: Failed to watch %v: %v", r.name, r.expectedType, err))
			}
			// If this is "connection refused" error, it means that most likely apiserver is not responsive.
			// It doesn't make sense to re-list all objects because most likely we will be able to restart
			// watch where we ended.
			// If that's the case wait and resend watch request.
			if urlError, ok := err.(*url.Error); ok {
				if opError, ok := urlError.Err.(*net.OpError); ok {
					if errno, ok := opError.Err.(syscall.Errno); ok && errno == syscall.ECONNREFUSED {
						time.Sleep(time.Second)
						continue
					}
				}
			}
			return nil
		}
		if err := r.watchHandler(w, &resourceVersion, resyncCh, stopCh); err != nil {
			if err != errorResyncRequested && err != errorStopRequested {
				glog.Warningf("%s: watch of %v ended with: %v", r.name, r.expectedType, err)
			}
			return nil
		}
		if r.canForceResyncNow() {
			glog.V(4).Infof("%s: next resync planned for %#v, forcing now", r.name, r.nextResync)
			return nil
		}
	}
}

// ListAndWatch first lists all items and get the resource version at the moment of call,
// and then use the resource version to watch.
// It returns error if ListAndWatch didn't even try to initialize watch.
func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
	glog.V(3).Infof("Listing and watching %v from %s", r.expectedType, r.name)
	var resourceVersion string
	resyncCh, cleanup := r.resyncChan()
	defer cleanup()

	// Explicitly set "0" as resource version - it's fine for the List()
	// to be served from cache and potentially be delayed relative to
	// etcd contents. Reflector framework will catch up via Watch() eventually.
	options := api.ListOptions{ResourceVersion: "0"}
	list, err := r.listerWatcher.List(options)
	if err != nil {
		return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err)
	}
	listMetaInterface, err := meta.ListAccessor(list)
	if err != nil {
		return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err)
	}
	resourceVersion = listMetaInterface.GetResourceVersion()
	items, err := meta.ExtractList(list)
	if err != nil {
		return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err)
	}
	if err := r.syncWith(items, resourceVersion); err != nil {
		return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err)
	}
	r.setLastSyncResourceVersion(resourceVersion)

	resyncerrc := make(chan error, 1)
	go func() {
		for {
			select {
			case <-resyncCh:
			case <-stopCh:
				return
			}
			glog.V(4).Infof("%s: forcing resync", r.name)
			if err := r.store.Resync(); err != nil {
				resyncerrc <- err
				return
			}
			cleanup()
			resyncCh, cleanup = r.resyncChan()
		}
	}()

	for {
		timemoutseconds := int64(minWatchTimeout.Seconds() * (rand.Float64() + 1.0))
		options = api.ListOptions{
			ResourceVersion: resourceVersion,
			// We want to avoid situations of hanging watchers. Stop any wachers that do not
			// receive any events within the timeout window.
			TimeoutSeconds: &timemoutseconds,
		}

		w, err := r.listerWatcher.Watch(options)
		if err != nil {
			switch err {
			case io.EOF:
				// watch closed normally
			case io.ErrUnexpectedEOF:
				glog.V(1).Infof("%s: Watch for %v closed with unexpected EOF: %v", r.name, r.expectedType, err)
			default:
				utilruntime.HandleError(fmt.Errorf("%s: Failed to watch %v: %v", r.name, r.expectedType, err))
			}
			// If this is "connection refused" error, it means that most likely apiserver is not responsive.
			// It doesn't make sense to re-list all objects because most likely we will be able to restart
			// watch where we ended.
			// If that's the case wait and resend watch request.
			if urlError, ok := err.(*url.Error); ok {
				if opError, ok := urlError.Err.(*net.OpError); ok {
					if errno, ok := opError.Err.(syscall.Errno); ok && errno == syscall.ECONNREFUSED {
						time.Sleep(time.Second)
						continue
					}
				}
			}
			return nil
		}

		if err := r.watchHandler(w, &resourceVersion, resyncerrc, stopCh); err != nil {
			if err != errorStopRequested {
				glog.Warningf("%s: watch of %v ended with: %v", r.name, r.expectedType, err)
			}
			return nil
		}
	}
}

// TODO: check for watch expired error and retry watch from latest point?  Same issue exists for Until.
func ListWatchUntil(timeout time.Duration, lw ListerWatcher, conditions ...watch.ConditionFunc) (*watch.Event, error) {
	if len(conditions) == 0 {
		return nil, nil
	}

	list, err := lw.List(v1.ListOptions{})
	if err != nil {
		return nil, err
	}
	initialItems, err := meta.ExtractList(list)
	if err != nil {
		return nil, err
	}

	// use the initial items as simulated "adds"
	var lastEvent *watch.Event
	currIndex := 0
	passedConditions := 0
	for _, condition := range conditions {
		// check the next condition against the previous event and short circuit waiting for the next watch
		if lastEvent != nil {
			done, err := condition(*lastEvent)
			if err != nil {
				return lastEvent, err
			}
			if done {
				passedConditions = passedConditions + 1
				continue
			}
		}

	ConditionSucceeded:
		for currIndex < len(initialItems) {
			lastEvent = &watch.Event{Type: watch.Added, Object: initialItems[currIndex]}
			currIndex++

			done, err := condition(*lastEvent)
			if err != nil {
				return lastEvent, err
			}
			if done {
				passedConditions = passedConditions + 1
				break ConditionSucceeded
			}
		}
	}
	if passedConditions == len(conditions) {
		return lastEvent, nil
	}
	remainingConditions := conditions[passedConditions:]

	metaObj, err := meta.ListAccessor(list)
	if err != nil {
		return nil, err
	}
	currResourceVersion := metaObj.GetResourceVersion()

	watchInterface, err := lw.Watch(v1.ListOptions{ResourceVersion: currResourceVersion})
	if err != nil {
		return nil, err
	}

	return watch.Until(timeout, watchInterface, remainingConditions...)
}

// GetReference returns an ObjectReference which refers to the given
// object, or an error if the object doesn't follow the conventions
// that would allow this.
// TODO: should take a meta.Interface see http://issue.k8s.io/7127
func GetReference(obj runtime.Object) (*ObjectReference, error) {
	if obj == nil {
		return nil, ErrNilObject
	}
	if ref, ok := obj.(*ObjectReference); ok {
		// Don't make a reference to a reference.
		return ref, nil
	}

	gvk := obj.GetObjectKind().GroupVersionKind()

	// if the object referenced is actually persisted, we can just get kind from meta
	// if we are building an object reference to something not yet persisted, we should fallback to scheme
	kind := gvk.Kind
	if len(kind) == 0 {
		// TODO: this is wrong
		gvks, _, err := Scheme.ObjectKinds(obj)
		if err != nil {
			return nil, err
		}
		kind = gvks[0].Kind
	}

	// An object that implements only List has enough metadata to build a reference
	var listMeta meta.List
	objectMeta, err := meta.Accessor(obj)
	if err != nil {
		listMeta, err = meta.ListAccessor(obj)
		if err != nil {
			return nil, err
		}
	} else {
		listMeta = objectMeta
	}

	// if the object referenced is actually persisted, we can also get version from meta
	version := gvk.GroupVersion().String()
	if len(version) == 0 {
		selfLink := listMeta.GetSelfLink()
		if len(selfLink) == 0 {
			return nil, ErrNoSelfLink
		}
		selfLinkUrl, err := url.Parse(selfLink)
		if err != nil {
			return nil, err
		}
		// example paths: /<prefix>/<version>/*
		parts := strings.Split(selfLinkUrl.Path, "/")
		if len(parts) < 3 {
			return nil, fmt.Errorf("unexpected self link format: '%v'; got version '%v'", selfLink, version)
		}
		version = parts[2]
	}

	// only has list metadata
	if objectMeta == nil {
		return &ObjectReference{
			Kind:            kind,
			APIVersion:      version,
			ResourceVersion: listMeta.GetResourceVersion(),
		}, nil
	}

	return &ObjectReference{
		Kind:            kind,
		APIVersion:      version,
		Name:            objectMeta.GetName(),
		Namespace:       objectMeta.GetNamespace(),
		UID:             objectMeta.GetUID(),
		ResourceVersion: objectMeta.GetResourceVersion(),
	}, nil
}

//.........这里部分代码省略.........
		var obj runtime.Object
		if singular {
			obj = infos[0].Object
		} else {
			// we have more than one item, so coerce all items into a list
			list := &runtime.UnstructuredList{
				Object: map[string]interface{}{
					"kind":       "List",
					"apiVersion": "v1",
					"metadata":   map[string]interface{}{},
				},
			}
			for _, info := range infos {
				list.Items = append(list.Items, info.Object.(*runtime.Unstructured))
			}
			obj = list
		}

		isList := meta.IsListType(obj)
		if isList {
			filteredResourceCount, items, err := cmdutil.FilterResourceList(obj, filterFuncs, filterOpts)
			if err != nil {
				return err
			}

			// take the filtered items and create a new list for display
			list := &runtime.UnstructuredList{
				Object: map[string]interface{}{
					"kind":       "List",
					"apiVersion": "v1",
					"metadata":   map[string]interface{}{},
				},
			}
			if listMeta, err := meta.ListAccessor(obj); err == nil {
				list.Object["selfLink"] = listMeta.GetSelfLink()
				list.Object["resourceVersion"] = listMeta.GetResourceVersion()
			}

			for _, item := range items {
				list.Items = append(list.Items, item.(*runtime.Unstructured))
			}
			if err := printer.PrintObj(list, out); err != nil {
				errs = append(errs, err)
			}

			cmdutil.PrintFilterCount(filteredResourceCount, res, filterOpts)
			return utilerrors.Reduce(utilerrors.Flatten(utilerrors.NewAggregate(errs)))
		}

		filteredResourceCount := 0
		if isFiltered, err := filterFuncs.Filter(obj, filterOpts); !isFiltered {
			if err != nil {
				glog.V(2).Infof("Unable to filter resource: %v", err)
			} else if err := printer.PrintObj(obj, out); err != nil {
				errs = append(errs, err)
			}
		} else if isFiltered {
			filteredResourceCount++
		}

		cmdutil.PrintFilterCount(filteredResourceCount, res, filterOpts)
		return utilerrors.Reduce(utilerrors.Flatten(utilerrors.NewAggregate(errs)))
	}

	allErrs := []error{}
	errs := sets.NewString()