Ejemplo n.º 1
0
// 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 := v1.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)
	cancelCh := make(chan struct{})
	defer close(cancelCh)
	go func() {
		for {
			select {
			case <-resyncCh:
			case <-stopCh:
				return
			case <-cancelCh:
				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 = v1.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
		}
	}
}
Ejemplo n.º 2
0
// 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...)
}
Ejemplo n.º 3
0
// 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 := api.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
}
Ejemplo n.º 4
0
// RunGet implements the generic Get command
// TODO: convert all direct flag accessors to a struct and pass that instead of cmd
func RunGet(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args []string, options *GetOptions) error {
	if len(options.Raw) > 0 {
		restClient, err := f.RESTClient()
		if err != nil {
			return err
		}

		stream, err := restClient.Get().RequestURI(options.Raw).Stream()
		if err != nil {
			return err
		}
		defer stream.Close()

		_, err = io.Copy(out, stream)
		if err != nil && err != io.EOF {
			return err
		}
		return nil
	}

	selector := cmdutil.GetFlagString(cmd, "selector")
	allNamespaces := cmdutil.GetFlagBool(cmd, "all-namespaces")
	showKind := cmdutil.GetFlagBool(cmd, "show-kind")
	mapper, typer, err := f.UnstructuredObject()
	if err != nil {
		return err
	}
	filterFuncs := f.DefaultResourceFilterFunc()
	filterOpts := f.DefaultResourceFilterOptions(cmd, allNamespaces)

	cmdNamespace, enforceNamespace, err := f.DefaultNamespace()
	if err != nil {
		return err
	}

	if allNamespaces {
		enforceNamespace = false
	}

	if len(args) == 0 && cmdutil.IsFilenameEmpty(options.Filenames) {
		fmt.Fprint(errOut, "You must specify the type of resource to get. ", valid_resources)

		fullCmdName := cmd.Parent().CommandPath()
		usageString := "Required resource not specified."
		if len(fullCmdName) > 0 && cmdutil.IsSiblingCommandExists(cmd, "explain") {
			usageString = fmt.Sprintf("%s\nUse \"%s explain <resource>\" for a detailed description of that resource (e.g. %[2]s explain pods).", usageString, fullCmdName)
		}

		return cmdutil.UsageError(cmd, usageString)
	}

	argsHasNames, err := resource.HasNames(args)
	if err != nil {
		return err
	}

	// always show resources when getting by name or filename, or if the output
	// is machine-consumable, or if multiple resource kinds were requested.
	if len(options.Filenames) > 0 || argsHasNames || cmdutil.OutputsRawFormat(cmd) {
		if !cmd.Flag("show-all").Changed {
			cmd.Flag("show-all").Value.Set("true")
		}
	}
	export := cmdutil.GetFlagBool(cmd, "export")

	// handle watch separately since we cannot watch multiple resource types
	isWatch, isWatchOnly := cmdutil.GetFlagBool(cmd, "watch"), cmdutil.GetFlagBool(cmd, "watch-only")
	if isWatch || isWatchOnly {
		r := resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.UnstructuredClientForMapping), unstructured.UnstructuredJSONScheme).
			NamespaceParam(cmdNamespace).DefaultNamespace().AllNamespaces(allNamespaces).
			FilenameParam(enforceNamespace, &options.FilenameOptions).
			SelectorParam(selector).
			ExportParam(export).
			ResourceTypeOrNameArgs(true, args...).
			SingleResourceType().
			Latest().
			Do()
		err := r.Err()
		if err != nil {
			return err
		}
		infos, err := r.Infos()
		if err != nil {
			return err
		}
		if len(infos) != 1 {
			return i18n.Errorf("watch is only supported on individual resources and resource collections - %d resources were found", len(infos))
		}
		info := infos[0]
		mapping := info.ResourceMapping()
		printer, err := f.PrinterForMapping(cmd, mapping, allNamespaces)
		if err != nil {
			return err
		}
		obj, err := r.Object()
		if err != nil {
			return err
		}

		// watching from resourceVersion 0, starts the watch at ~now and
		// will return an initial watch event.  Starting form ~now, rather
		// the rv of the object will insure that we start the watch from
		// inside the watch window, which the rv of the object might not be.
		rv := "0"
		isList := meta.IsListType(obj)
		if isList {
			// the resourceVersion of list objects is ~now but won't return
			// an initial watch event
			rv, err = mapping.MetadataAccessor.ResourceVersion(obj)
			if err != nil {
				return err
			}
		}

		// print the current object
		filteredResourceCount := 0
		if !isWatchOnly {
			if err := printer.PrintObj(obj, out); err != nil {
				return fmt.Errorf("unable to output the provided object: %v", err)
			}
			filteredResourceCount++
			cmdutil.PrintFilterCount(filteredResourceCount, mapping.Resource, filterOpts)
		}

		// print watched changes
		w, err := r.Watch(rv)
		if err != nil {
			return err
		}

		first := true
		filteredResourceCount = 0
		intr := interrupt.New(nil, w.Stop)
		intr.Run(func() error {
			_, err := watch.Until(0, w, func(e watch.Event) (bool, error) {
				if !isList && first {
					// drop the initial watch event in the single resource case
					first = false
					return false, nil
				}
				err := printer.PrintObj(e.Object, out)
				if err != nil {
					return false, err
				}
				filteredResourceCount++
				cmdutil.PrintFilterCount(filteredResourceCount, mapping.Resource, filterOpts)
				return false, nil
			})
			return err
		})
		return nil
	}

	r := resource.NewBuilder(mapper, typer, resource.ClientMapperFunc(f.UnstructuredClientForMapping), unstructured.UnstructuredJSONScheme).
		NamespaceParam(cmdNamespace).DefaultNamespace().AllNamespaces(allNamespaces).
		FilenameParam(enforceNamespace, &options.FilenameOptions).
		SelectorParam(selector).
		ExportParam(export).
		ResourceTypeOrNameArgs(true, args...).
		ContinueOnError().
		Latest().
		Flatten().
		Do()
	err = r.Err()
	if err != nil {
		return err
	}

	printer, generic, err := cmdutil.PrinterForCommand(cmd)
	if err != nil {
		return err
	}

	if generic {
		// we flattened the data from the builder, so we have individual items, but now we'd like to either:
		// 1. if there is more than one item, combine them all into a single list
		// 2. if there is a single item and that item is a list, leave it as its specific list
		// 3. if there is a single item and it is not a a list, leave it as a single item
		var errs []error
		singleItemImplied := false
		infos, err := r.IntoSingleItemImplied(&singleItemImplied).Infos()
		if err != nil {
			if singleItemImplied {
				return err
			}
			errs = append(errs, err)
		}
		if len(infos) == 0 && len(errs) == 0 {
			outputEmptyListWarning(errOut)
		}

		res := ""
		if len(infos) > 0 {
			res = infos[0].ResourceMapping().Resource
		}

		var obj runtime.Object
		if !singleItemImplied || len(infos) > 1 {
			// we have more than one item, so coerce all items into a list
			list := &unstructured.UnstructuredList{
				Object: map[string]interface{}{
					"kind":       "List",
					"apiVersion": "v1",
					"metadata":   map[string]interface{}{},
				},
			}
			for _, info := range infos {
				list.Items = append(list.Items, info.Object.(*unstructured.Unstructured))
			}
			obj = list
		} else {
			obj = infos[0].Object
		}

		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 := &unstructured.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.(*unstructured.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()
	infos, err := r.Infos()
	if err != nil {
		allErrs = append(allErrs, err)
	}
	if len(infos) == 0 && len(allErrs) == 0 {
		outputEmptyListWarning(errOut)
	}

	objs := make([]runtime.Object, len(infos))
	for ix := range infos {
		objs[ix] = infos[ix].Object
	}

	sorting, err := cmd.Flags().GetString("sort-by")
	if err != nil {
		return err
	}
	var sorter *kubectl.RuntimeSort
	if len(sorting) > 0 && len(objs) > 1 {
		// TODO: questionable
		if sorter, err = kubectl.SortObjects(f.Decoder(true), objs, sorting); err != nil {
			return err
		}
	}

	// use the default printer for each object
	printer = nil
	var lastMapping *meta.RESTMapping
	w := kubectl.GetNewTabWriter(out)
	filteredResourceCount := 0

	if resource.MultipleTypesRequested(args) || cmdutil.MustPrintWithKinds(objs, infos, sorter) {
		showKind = true
	}

	for ix := range objs {
		var mapping *meta.RESTMapping
		var original runtime.Object
		if sorter != nil {
			mapping = infos[sorter.OriginalPosition(ix)].Mapping
			original = infos[sorter.OriginalPosition(ix)].Object
		} else {
			mapping = infos[ix].Mapping
			original = infos[ix].Object
		}
		if printer == nil || lastMapping == nil || mapping == nil || mapping.Resource != lastMapping.Resource {
			if printer != nil {
				w.Flush()
				cmdutil.PrintFilterCount(filteredResourceCount, lastMapping.Resource, filterOpts)
			}
			printer, err = f.PrinterForMapping(cmd, mapping, allNamespaces)
			if err != nil {
				if !errs.Has(err.Error()) {
					errs.Insert(err.Error())
					allErrs = append(allErrs, err)
				}
				continue
			}

			// add linebreak between resource groups (if there is more than one)
			// skip linebreak above first resource group
			noHeaders := cmdutil.GetFlagBool(cmd, "no-headers")
			if lastMapping != nil && !noHeaders {
				fmt.Fprintf(errOut, "%s\n", "")
			}

			lastMapping = mapping
		}

		// try to convert before apply filter func
		decodedObj, _ := kubectl.DecodeUnknownObject(original)

		// filter objects if filter has been defined for current object
		if isFiltered, err := filterFuncs.Filter(decodedObj, filterOpts); isFiltered {
			if err == nil {
				filteredResourceCount++
				continue
			}
			if !errs.Has(err.Error()) {
				errs.Insert(err.Error())
				allErrs = append(allErrs, err)
			}
		}

		if resourcePrinter, found := printer.(*kubectl.HumanReadablePrinter); found {
			resourceName := resourcePrinter.GetResourceKind()
			if mapping != nil {
				if resourceName == "" {
					resourceName = mapping.Resource
				}
				if alias, ok := kubectl.ResourceShortFormFor(mapping.Resource); ok {
					resourceName = alias
				} else if resourceName == "" {
					resourceName = "none"
				}
			} else {
				resourceName = "none"
			}

			if showKind {
				resourcePrinter.EnsurePrintWithKind(resourceName)
			}

			if err := printer.PrintObj(decodedObj, w); err != nil {
				if !errs.Has(err.Error()) {
					errs.Insert(err.Error())
					allErrs = append(allErrs, err)
				}
			}
			continue
		}
		if err := printer.PrintObj(decodedObj, w); err != nil {
			if !errs.Has(err.Error()) {
				errs.Insert(err.Error())
				allErrs = append(allErrs, err)
			}
			continue
		}
	}
	w.Flush()
	if printer != nil && lastMapping != nil {
		cmdutil.PrintFilterCount(filteredResourceCount, lastMapping.Resource, filterOpts)
	}
	return utilerrors.NewAggregate(allErrs)
}