func (s *CustomColumnsPrinter) PrintObj(obj runtime.Object, out io.Writer) error {
	w := tabwriter.NewWriter(out, columnwidth, tabwidth, padding, padding_character, flags)

	if !s.NoHeaders {
		headers := make([]string, len(s.Columns))
		for ix := range s.Columns {
			headers[ix] = s.Columns[ix].Header
		}
		fmt.Fprintln(w, strings.Join(headers, "\t"))
	}
	parsers := make([]*jsonpath.JSONPath, len(s.Columns))
	for ix := range s.Columns {
		parsers[ix] = jsonpath.New(fmt.Sprintf("column%d", ix))
		if err := parsers[ix].Parse(s.Columns[ix].FieldSpec); err != nil {
			return err
		}
	}

	if meta.IsListType(obj) {
		objs, err := meta.ExtractList(obj)
		if err != nil {
			return err
		}
		for ix := range objs {
			if err := s.printOneObject(objs[ix], parsers, w); err != nil {
				return err
			}
		}
	} else {
		if err := s.printOneObject(obj, parsers, w); err != nil {
			return err
		}
	}
	return w.Flush()
}
Esempio n. 2
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func (s *SortingPrinter) PrintObj(obj runtime.Object, out io.Writer) error {
	if !meta.IsListType(obj) {
		return s.Delegate.PrintObj(obj, out)
	}

	if err := s.sortObj(obj); err != nil {
		return err
	}
	return s.Delegate.PrintObj(obj, out)
}
Esempio n. 3
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func (t *tracker) Add(obj runtime.Object) error {
	if meta.IsListType(obj) {
		return t.addList(obj, false)
	}

	objMeta, err := meta.Accessor(obj)
	if err != nil {
		return err
	}
	return t.add(obj, objMeta.GetNamespace(), false)
}
func TestIsList(t *testing.T) {
	tests := []struct {
		obj    runtime.Object
		isList bool
	}{
		{&api.PodList{}, true},
		{&api.Pod{}, false},
	}
	for _, item := range tests {
		if e, a := item.isList, meta.IsListType(item.obj); e != a {
			t.Errorf("%v: Expected %v, got %v", reflect.TypeOf(item.obj), e, a)
		}
	}
}
Esempio n. 5
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// RetrieveLatest updates the Object on each Info by invoking a standard client
// Get.
func RetrieveLatest(info *Info, err error) error {
	if err != nil {
		return err
	}
	if meta.IsListType(info.Object) {
		return fmt.Errorf("watch is only supported on individual resources and resource collections, but a list of resources is found")
	}
	if len(info.Name) == 0 {
		return nil
	}
	if info.Namespaced() && len(info.Namespace) == 0 {
		return fmt.Errorf("no namespace set on resource %s %q", info.Mapping.Resource, info.Name)
	}
	return info.Get()
}
Esempio n. 6
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// setListSelfLink sets the self link of a list to the base URL, then sets the self links
// on all child objects returned. Returns the number of items in the list.
func setListSelfLink(obj runtime.Object, req *restful.Request, namer ScopeNamer) (int, error) {
	if !meta.IsListType(obj) {
		return 0, nil
	}

	uri, err := namer.GenerateListLink(req)
	if err != nil {
		return 0, err
	}
	if err := namer.SetSelfLink(obj, uri); err != nil {
		glog.V(4).Infof("Unable to set self link on object: %v", err)
	}

	count := 0
	err = meta.EachListItem(obj, func(obj runtime.Object) error {
		count++
		return setSelfLink(obj, req, namer)
	})
	return count, err
}
Esempio n. 7
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func (t *tracker) List(gvk schema.GroupVersionKind, ns string) (runtime.Object, error) {
	// Heuristic for list kind: original kind + List suffix. Might
	// not always be true but this tracker has a pretty limited
	// understanding of the actual API model.
	listGVK := gvk
	listGVK.Kind = listGVK.Kind + "List"

	list, err := t.scheme.New(listGVK)
	if err != nil {
		return nil, err
	}

	if !meta.IsListType(list) {
		return nil, fmt.Errorf("%q is not a list type", listGVK.Kind)
	}

	t.lock.RLock()
	defer t.lock.RUnlock()

	objs, ok := t.objects[gvk]
	if !ok {
		return list, nil
	}

	matchingObjs, err := filterByNamespaceAndName(objs, ns, "")
	if err != nil {
		return nil, err
	}
	if err := meta.SetList(list, matchingObjs); err != nil {
		return nil, err
	}
	if list, err = t.scheme.Copy(list); err != nil {
		return nil, err
	}
	return list, nil
}
Esempio n. 8
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// RunConvert implements the generic Convert command
func (o *ConvertOptions) RunConvert() error {
	r := o.builder.Do()
	err := r.Err()
	if err != nil {
		return err
	}

	singleItemImplied := false
	infos, err := r.IntoSingleItemImplied(&singleItemImplied).Infos()
	if err != nil {
		return err
	}

	if len(infos) == 0 {
		return fmt.Errorf("no objects passed to convert")
	}

	objects, err := resource.AsVersionedObject(infos, !singleItemImplied, o.outputVersion, o.encoder)
	if err != nil {
		return err
	}

	if meta.IsListType(objects) {
		_, items, err := cmdutil.FilterResourceList(objects, nil, nil)
		if err != nil {
			return err
		}
		filteredObj, err := cmdutil.ObjectListToVersionedObject(items, o.outputVersion)
		if err != nil {
			return err
		}
		return o.printer.PrintObj(filteredObj, o.out)
	}

	return o.printer.PrintObj(objects, o.out)
}
Esempio n. 9
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// Object returns a single object representing the output of a single visit to all
// found resources.  If the Builder was a singular context (expected to return a
// single resource by user input) and only a single resource was found, the resource
// will be returned as is.  Otherwise, the returned resources will be part of an
// api.List. The ResourceVersion of the api.List will be set only if it is identical
// across all infos returned.
func (r *Result) Object() (runtime.Object, error) {
	infos, err := r.Infos()
	if err != nil {
		return nil, err
	}

	versions := sets.String{}
	objects := []runtime.Object{}
	for _, info := range infos {
		if info.Object != nil {
			objects = append(objects, info.Object)
			versions.Insert(info.ResourceVersion)
		}
	}

	if len(objects) == 1 {
		if r.singleItemImplied {
			return objects[0], nil
		}
		// if the item is a list already, don't create another list
		if meta.IsListType(objects[0]) {
			return objects[0], nil
		}
	}

	version := ""
	if len(versions) == 1 {
		version = versions.List()[0]
	}
	return &api.List{
		ListMeta: metav1.ListMeta{
			ResourceVersion: version,
		},
		Items: objects,
	}, err
}
Esempio n. 10
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// ListResource returns a function that handles retrieving a list of resources from a rest.Storage object.
func ListResource(r rest.Lister, rw rest.Watcher, scope RequestScope, forceWatch bool, minRequestTimeout time.Duration) restful.RouteFunction {
	return func(req *restful.Request, res *restful.Response) {
		// For performance tracking purposes.
		trace := util.NewTrace("List " + req.Request.URL.Path)

		w := res.ResponseWriter

		namespace, err := scope.Namer.Namespace(req)
		if err != nil {
			scope.err(err, res.ResponseWriter, req.Request)
			return
		}

		// Watches for single objects are routed to this function.
		// Treat a /name parameter the same as a field selector entry.
		hasName := true
		_, name, err := scope.Namer.Name(req)
		if err != nil {
			hasName = false
		}

		ctx := scope.ContextFunc(req)
		ctx = request.WithNamespace(ctx, namespace)

		opts := api.ListOptions{}
		if err := scope.ParameterCodec.DecodeParameters(req.Request.URL.Query(), scope.Kind.GroupVersion(), &opts); err != nil {
			scope.err(err, res.ResponseWriter, req.Request)
			return
		}

		// transform fields
		// TODO: DecodeParametersInto should do this.
		if opts.FieldSelector != nil {
			fn := func(label, value string) (newLabel, newValue string, err error) {
				return scope.Convertor.ConvertFieldLabel(scope.Kind.GroupVersion().String(), scope.Kind.Kind, label, value)
			}
			if opts.FieldSelector, err = opts.FieldSelector.Transform(fn); err != nil {
				// TODO: allow bad request to set field causes based on query parameters
				err = errors.NewBadRequest(err.Error())
				scope.err(err, res.ResponseWriter, req.Request)
				return
			}
		}

		if hasName {
			// metadata.name is the canonical internal name.
			// SelectionPredicate will notice that this is
			// a request for a single object and optimize the
			// storage query accordingly.
			nameSelector := fields.OneTermEqualSelector("metadata.name", name)
			if opts.FieldSelector != nil && !opts.FieldSelector.Empty() {
				// It doesn't make sense to ask for both a name
				// and a field selector, since just the name is
				// sufficient to narrow down the request to a
				// single object.
				scope.err(errors.NewBadRequest("both a name and a field selector provided; please provide one or the other."), res.ResponseWriter, req.Request)
				return
			}
			opts.FieldSelector = nameSelector
		}

		if (opts.Watch || forceWatch) && rw != nil {
			watcher, err := rw.Watch(ctx, &opts)
			if err != nil {
				scope.err(err, res.ResponseWriter, req.Request)
				return
			}
			// TODO: Currently we explicitly ignore ?timeout= and use only ?timeoutSeconds=.
			timeout := time.Duration(0)
			if opts.TimeoutSeconds != nil {
				timeout = time.Duration(*opts.TimeoutSeconds) * time.Second
			}
			if timeout == 0 && minRequestTimeout > 0 {
				timeout = time.Duration(float64(minRequestTimeout) * (rand.Float64() + 1.0))
			}
			serveWatch(watcher, scope, req, res, timeout)
			return
		}

		// Log only long List requests (ignore Watch).
		defer trace.LogIfLong(500 * time.Millisecond)
		trace.Step("About to List from storage")
		result, err := r.List(ctx, &opts)
		if err != nil {
			scope.err(err, res.ResponseWriter, req.Request)
			return
		}
		trace.Step("Listing from storage done")
		numberOfItems, err := setListSelfLink(result, req, scope.Namer)
		if err != nil {
			scope.err(err, res.ResponseWriter, req.Request)
			return
		}
		trace.Step("Self-linking done")
		// Ensure empty lists return a non-nil items slice
		if numberOfItems == 0 && meta.IsListType(result) {
			if err := meta.SetList(result, []runtime.Object{}); err != nil {
				scope.err(err, res.ResponseWriter, req.Request)
				return
			}
		}
		responsewriters.WriteObject(http.StatusOK, scope.Kind.GroupVersion(), scope.Serializer, result, w, req.Request)
		trace.Step(fmt.Sprintf("Writing http response done (%d items)", numberOfItems))
	}
}
Esempio n. 11
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func visitToPatch(
	originalObj runtime.Object,
	updates *resource.Info,
	mapper meta.RESTMapper,
	resourceMapper *resource.Mapper,
	encoder runtime.Encoder,
	out, errOut io.Writer,
	defaultVersion schema.GroupVersion,
	results *editResults,
	file string,
) error {

	patchVisitor := resource.NewFlattenListVisitor(updates, resourceMapper)
	err := patchVisitor.Visit(func(info *resource.Info, incomingErr error) error {
		currOriginalObj := originalObj

		// if we're editing a list, then navigate the list to find the item that we're currently trying to edit
		if meta.IsListType(originalObj) {
			currOriginalObj = nil
			editObjUID, err := meta.NewAccessor().UID(info.Object)
			if err != nil {
				return err
			}

			listItems, err := meta.ExtractList(originalObj)
			if err != nil {
				return err
			}

			// iterate through the list to find the item with the matching UID
			for i := range listItems {
				originalObjUID, err := meta.NewAccessor().UID(listItems[i])
				if err != nil {
					return err
				}
				if editObjUID == originalObjUID {
					currOriginalObj = listItems[i]
					break
				}
			}
			if currOriginalObj == nil {
				return fmt.Errorf("no original object found for %#v", info.Object)
			}

		}

		originalSerialization, err := runtime.Encode(encoder, currOriginalObj)
		if err != nil {
			return err
		}
		editedSerialization, err := runtime.Encode(encoder, info.Object)
		if err != nil {
			return err
		}

		// compute the patch on a per-item basis
		// use strategic merge to create a patch
		originalJS, err := yaml.ToJSON(originalSerialization)
		if err != nil {
			return err
		}
		editedJS, err := yaml.ToJSON(editedSerialization)
		if err != nil {
			return err
		}

		if reflect.DeepEqual(originalJS, editedJS) {
			// no edit, so just skip it.
			cmdutil.PrintSuccess(mapper, false, out, info.Mapping.Resource, info.Name, false, "skipped")
			return nil
		}

		preconditions := []strategicpatch.PreconditionFunc{strategicpatch.RequireKeyUnchanged("apiVersion"),
			strategicpatch.RequireKeyUnchanged("kind"), strategicpatch.RequireMetadataKeyUnchanged("name")}
		patch, err := strategicpatch.CreateTwoWayMergePatch(originalJS, editedJS, currOriginalObj, preconditions...)
		if err != nil {
			glog.V(4).Infof("Unable to calculate diff, no merge is possible: %v", err)
			if strategicpatch.IsPreconditionFailed(err) {
				return fmt.Errorf("%s", "At least one of apiVersion, kind and name was changed")
			}
			return err
		}

		results.version = defaultVersion
		patched, err := resource.NewHelper(info.Client, info.Mapping).Patch(info.Namespace, info.Name, types.StrategicMergePatchType, patch)
		if err != nil {
			fmt.Fprintln(out, results.addError(err, info))
			return nil
		}
		info.Refresh(patched, true)
		cmdutil.PrintSuccess(mapper, false, out, info.Mapping.Resource, info.Name, false, "edited")
		return nil
	})
	return err
}
Esempio n. 12
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func runEdit(f cmdutil.Factory, out, errOut io.Writer, cmd *cobra.Command, args []string, options *resource.FilenameOptions, editMode EditMode) error {
	o, err := getPrinter(cmd)
	if err != nil {
		return err
	}

	mapper, resourceMapper, r, cmdNamespace, err := getMapperAndResult(f, args, options, editMode)
	if err != nil {
		return err
	}

	clientConfig, err := f.ClientConfig()
	if err != nil {
		return err
	}

	encoder := f.JSONEncoder()
	defaultVersion, err := cmdutil.OutputVersion(cmd, clientConfig.GroupVersion)
	if err != nil {
		return err
	}

	normalEditInfos, err := r.Infos()
	if err != nil {
		return err
	}

	var (
		windowsLineEndings = cmdutil.GetFlagBool(cmd, "windows-line-endings")
		edit               = editor.NewDefaultEditor(f.EditorEnvs())
	)

	editFn := func(info *resource.Info, err error) error {
		var (
			results  = editResults{}
			original = []byte{}
			edited   = []byte{}
			file     string
		)

		containsError := false
		var infos []*resource.Info
		for {
			switch editMode {
			case NormalEditMode:
				infos = normalEditInfos
			case EditBeforeCreateMode:
				infos = []*resource.Info{info}
			default:
				err = fmt.Errorf("Not supported edit mode %q", editMode)
			}
			originalObj, err := resource.AsVersionedObject(infos, false, defaultVersion, encoder)
			if err != nil {
				return err
			}

			objToEdit := originalObj

			// generate the file to edit
			buf := &bytes.Buffer{}
			var w io.Writer = buf
			if windowsLineEndings {
				w = crlf.NewCRLFWriter(w)
			}

			if o.addHeader {
				results.header.writeTo(w)
			}

			if !containsError {
				if err := o.printer.PrintObj(objToEdit, w); err != nil {
					return preservedFile(err, results.file, errOut)
				}
				original = buf.Bytes()
			} else {
				// In case of an error, preserve the edited file.
				// Remove the comments (header) from it since we already
				// have included the latest header in the buffer above.
				buf.Write(manualStrip(edited))
			}

			// launch the editor
			editedDiff := edited
			edited, file, err = edit.LaunchTempFile(fmt.Sprintf("%s-edit-", filepath.Base(os.Args[0])), o.ext, buf)
			if err != nil {
				return preservedFile(err, results.file, errOut)
			}
			if editMode == NormalEditMode || containsError {
				if bytes.Equal(stripComments(editedDiff), stripComments(edited)) {
					// Ugly hack right here. We will hit this either (1) when we try to
					// save the same changes we tried to save in the previous iteration
					// which means our changes are invalid or (2) when we exit the second
					// time. The second case is more usual so we can probably live with it.
					// TODO: A less hacky fix would be welcome :)
					return preservedFile(fmt.Errorf("%s", "Edit cancelled, no valid changes were saved."), file, errOut)
				}
			}

			// cleanup any file from the previous pass
			if len(results.file) > 0 {
				os.Remove(results.file)
			}
			glog.V(4).Infof("User edited:\n%s", string(edited))

			// Apply validation
			schema, err := f.Validator(cmdutil.GetFlagBool(cmd, "validate"), cmdutil.GetFlagString(cmd, "schema-cache-dir"))
			if err != nil {
				return preservedFile(err, file, errOut)
			}
			err = schema.ValidateBytes(stripComments(edited))
			if err != nil {
				results = editResults{
					file: file,
				}
				containsError = true
				fmt.Fprintln(out, results.addError(errors.NewInvalid(api.Kind(""), "", field.ErrorList{field.Invalid(nil, "The edited file failed validation", fmt.Sprintf("%v", err))}), infos[0]))
				continue
			}

			// Compare content without comments
			if bytes.Equal(stripComments(original), stripComments(edited)) {
				os.Remove(file)
				fmt.Fprintln(errOut, "Edit cancelled, no changes made.")
				return nil
			}

			lines, err := hasLines(bytes.NewBuffer(edited))
			if err != nil {
				return preservedFile(err, file, errOut)
			}
			if !lines {
				os.Remove(file)
				fmt.Fprintln(errOut, "Edit cancelled, saved file was empty.")
				return nil
			}

			results = editResults{
				file: file,
			}

			// parse the edited file
			updates, err := resourceMapper.InfoForData(edited, "edited-file")
			if err != nil {
				// syntax error
				containsError = true
				results.header.reasons = append(results.header.reasons, editReason{head: fmt.Sprintf("The edited file had a syntax error: %v", err)})
				continue
			}
			// not a syntax error as it turns out...
			containsError = false

			namespaceVisitor := resource.NewFlattenListVisitor(updates, resourceMapper)
			// need to make sure the original namespace wasn't changed while editing
			if err = namespaceVisitor.Visit(resource.RequireNamespace(cmdNamespace)); err != nil {
				return preservedFile(err, file, errOut)
			}

			// iterate through all items to apply annotations
			mutatedObjects, err := visitAnnotation(cmd, f, updates, resourceMapper, encoder)
			if err != nil {
				return preservedFile(err, file, errOut)
			}

			// if we mutated a list in the visitor, persist the changes on the overall object
			if meta.IsListType(updates.Object) {
				meta.SetList(updates.Object, mutatedObjects)
			}

			switch editMode {
			case NormalEditMode:
				err = visitToPatch(originalObj, updates, mapper, resourceMapper, encoder, out, errOut, defaultVersion, &results, file)
			case EditBeforeCreateMode:
				err = visitToCreate(updates, mapper, resourceMapper, out, errOut, defaultVersion, &results, file)
			default:
				err = fmt.Errorf("Not supported edit mode %q", editMode)
			}
			if err != nil {
				return preservedFile(err, results.file, errOut)
			}

			// Handle all possible errors
			//
			// 1. retryable: propose kubectl replace -f
			// 2. notfound: indicate the location of the saved configuration of the deleted resource
			// 3. invalid: retry those on the spot by looping ie. reloading the editor
			if results.retryable > 0 {
				fmt.Fprintf(errOut, "You can run `%s replace -f %s` to try this update again.\n", filepath.Base(os.Args[0]), file)
				return cmdutil.ErrExit
			}
			if results.notfound > 0 {
				fmt.Fprintf(errOut, "The edits you made on deleted resources have been saved to %q\n", file)
				return cmdutil.ErrExit
			}

			if len(results.edit) == 0 {
				if results.notfound == 0 {
					os.Remove(file)
				} else {
					fmt.Fprintf(out, "The edits you made on deleted resources have been saved to %q\n", file)
				}
				return nil
			}

			if len(results.header.reasons) > 0 {
				containsError = true
			}
		}
	}

	switch editMode {
	// If doing normal edit we cannot use Visit because we need to edit a list for convenience. Ref: #20519
	case NormalEditMode:
		return editFn(nil, nil)
	// If doing an edit before created, we don't want a list and instead want the normal behavior as kubectl create.
	case EditBeforeCreateMode:
		return r.Visit(editFn)
	default:
		return fmt.Errorf("Not supported edit mode %q", editMode)
	}
}
Esempio n. 13
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// 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)
}