Make a change to visitor to allow it to accept an error, like Go's path walker

pkg/kubectl/cmd/annotation.go

@@ -166,16 +166,19 @@ func (o AnnotateOptions) RunAnnotate() error {
 	if err := r.Err(); err != nil {
 		return err
 	}
-	return r.Visit(func(info *resource.Info) error {
+	return r.Visit(func(info *resource.Info, err error) error {
-		_, err := cmdutil.UpdateObject(info, func(obj runtime.Object) error {
+		if err != nil {
+			return err
+		}
+		_, uErr := cmdutil.UpdateObject(info, func(obj runtime.Object) error {
 			err := o.updateAnnotations(obj)
 			if err != nil {
 				return err
 			}
 			return nil
 		})
-		if err != nil {
+		if uErr != nil {
-			return err
+			return uErr
 		}
 		return nil
 	})

pkg/kubectl/cmd/clusterinfo.go

@@ -68,7 +68,10 @@ func RunClusterInfo(factory *cmdutil.Factory, out io.Writer, cmd *cobra.Command)
 		SelectorParam("kubernetes.io/cluster-service=true").
 		ResourceTypeOrNameArgs(false, []string{"services"}...).
 		Latest()
-	b.Do().Visit(func(r *resource.Info) error {
+	b.Do().Visit(func(r *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		services := r.Object.(*api.ServiceList).Items
 		for _, service := range services {
 			var link string

pkg/kubectl/cmd/create.go

@@ -96,7 +96,10 @@ func RunCreate(f *cmdutil.Factory, cmd *cobra.Command, out io.Writer) error {
 	}
 
 	count := 0
-	err = r.Visit(func(info *resource.Info) error {
+	err = r.Visit(func(info *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		data, err := info.Mapping.Codec.Encode(info.Object)
 		if err != nil {
 			return cmdutil.AddSourceToErr("creating", info.Source, err)

pkg/kubectl/cmd/delete.go

@@ -132,7 +132,10 @@ func ReapResult(r *resource.Result, f *cmdutil.Factory, out io.Writer, isDefault
 	if ignoreNotFound {
 		r = r.IgnoreErrors(errors.IsNotFound)
 	}
-	err := r.Visit(func(info *resource.Info) error {
+	err := r.Visit(func(info *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		found++
 		reaper, err := f.Reaper(info.Mapping)
 		if err != nil {
@@ -166,7 +169,10 @@ func DeleteResult(r *resource.Result, out io.Writer, ignoreNotFound bool, shortO
 	if ignoreNotFound {
 		r = r.IgnoreErrors(errors.IsNotFound)
 	}
-	err := r.Visit(func(info *resource.Info) error {
+	err := r.Visit(func(info *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		found++
 		return deleteResource(info, out, shortOutput, mapper)
 	})

pkg/kubectl/cmd/get.go

@@ -205,7 +205,10 @@ func RunGet(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []string
 	}
 
 	// use the default printer for each object
-	return b.Do().Visit(func(r *resource.Info) error {
+	return b.Do().Visit(func(r *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		printer, err := f.PrinterForMapping(cmd, r.Mapping, allNamespaces)
 		if err != nil {
 			return err

pkg/kubectl/cmd/label.go

@@ -199,7 +199,10 @@ func RunLabel(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []stri
 	}
 
 	// TODO: support bulk generic output a la Get
-	return r.Visit(func(info *resource.Info) error {
+	return r.Visit(func(info *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		obj, err := cmdutil.UpdateObject(info, func(obj runtime.Object) error {
 			err := labelFunc(obj, overwrite, resourceVersion, labels, remove)
 			if err != nil {

pkg/kubectl/cmd/replace.go

@@ -115,7 +115,10 @@ func RunReplace(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []st
 		return err
 	}
 
-	return r.Visit(func(info *resource.Info) error {
+	return r.Visit(func(info *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		data, err := info.Mapping.Codec.Encode(info.Object)
 		if err != nil {
 			return cmdutil.AddSourceToErr("replacing", info.Source, err)
@@ -196,7 +199,10 @@ func forceReplace(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, args []
 	}
 
 	count := 0
-	err = r.Visit(func(info *resource.Info) error {
+	err = r.Visit(func(info *resource.Info, err error) error {
+		if err != nil {
+			return err
+		}
 		data, err := info.Mapping.Codec.Encode(info.Object)
 		if err != nil {
 			return err

pkg/kubectl/resource/builder.go

@@ -133,7 +133,7 @@ func (b *Builder) URL(urls ...*url.URL) *Builder {
 // will be ignored (but logged at V(2)).
 func (b *Builder) Stdin() *Builder {
 	b.stream = true
-	b.paths = append(b.paths, FileVisitorForSTDIN(b.mapper, b.continueOnError, b.schema))
+	b.paths = append(b.paths, FileVisitorForSTDIN(b.mapper, b.schema))
 	return b
 }
 
@@ -143,7 +143,7 @@ func (b *Builder) Stdin() *Builder {
 // will be ignored (but logged at V(2)).
 func (b *Builder) Stream(r io.Reader, name string) *Builder {
 	b.stream = true
-	b.paths = append(b.paths, NewStreamVisitor(r, b.mapper, name, b.continueOnError, b.schema))
+	b.paths = append(b.paths, NewStreamVisitor(r, b.mapper, name, b.schema))
 	return b
 }
 
@@ -164,7 +164,7 @@ func (b *Builder) Path(paths ...string) *Builder {
 			continue
 		}
 
-		visitors, err := ExpandPathsToFileVisitors(b.mapper, p, false, []string{".json", ".stdin", ".yaml", ".yml"}, b.continueOnError, b.schema)
+		visitors, err := ExpandPathsToFileVisitors(b.mapper, p, false, []string{".json", ".stdin", ".yaml", ".yml"}, b.schema)
 		if err != nil {
 			b.errs = append(b.errs, fmt.Errorf("error reading %q: %v", p, err))
 		}

pkg/kubectl/resource/builder_test.go

@@ -162,7 +162,10 @@ type testVisitor struct {
 	Infos     []*Info
 }
 
-func (v *testVisitor) Handle(info *Info) error {
+func (v *testVisitor) Handle(info *Info, err error) error {
+	if err != nil {
+		return err
+	}
 	v.Infos = append(v.Infos, info)
 	return v.InjectErr
 }
@@ -649,7 +652,7 @@ func TestContinueOnErrorVisitor(t *testing.T) {
 		Do()
 	count := 0
 	testErr := fmt.Errorf("test error")
-	err := req.Visit(func(_ *Info) error {
+	err := req.Visit(func(_ *Info, _ error) error {
 		count++
 		if count > 1 {
 			return testErr
@@ -872,40 +875,6 @@ func TestLatest(t *testing.T) {
 	}
 }
 
-func TestIgnoreStreamErrors(t *testing.T) {
-	pods, svc := testData()
-
-	r, w := io.Pipe()
-	go func() {
-		defer w.Close()
-		w.Write([]byte(`{}`))
-		w.Write([]byte(runtime.EncodeOrDie(latest.Codec, &pods.Items[0])))
-	}()
-
-	r2, w2 := io.Pipe()
-	go func() {
-		defer w2.Close()
-		w2.Write([]byte(`{}`))
-		w2.Write([]byte(runtime.EncodeOrDie(latest.Codec, &svc.Items[0])))
-	}()
-
-	b := NewBuilder(latest.RESTMapper, api.Scheme, fakeClient()).
-		ContinueOnError(). // TODO: order seems bad, but allows clients to determine what they want...
-		Stream(r, "1").Stream(r2, "2")
-
-	test := &testVisitor{}
-	singular := false
-
-	err := b.Do().IntoSingular(&singular).Visit(test.Handle)
-	if err != nil || singular || len(test.Infos) != 2 {
-		t.Fatalf("unexpected response: %v %t %#v", err, singular, test.Infos)
-	}
-
-	if !api.Semantic.DeepDerivative([]runtime.Object{&pods.Items[0], &svc.Items[0]}, test.Objects()) {
-		t.Errorf("unexpected visited objects: %#v", test.Objects())
-	}
-}
-
 func TestReceiveMultipleErrors(t *testing.T) {
 	pods, svc := testData()
 
@@ -931,7 +900,7 @@ func TestReceiveMultipleErrors(t *testing.T) {
 	singular := false
 
 	err := b.Do().IntoSingular(&singular).Visit(test.Handle)
-	if err == nil || singular || len(test.Infos) != 0 {
+	if err == nil || singular || len(test.Infos) != 2 {
 		t.Fatalf("unexpected response: %v %t %#v", err, singular, test.Infos)
 	}
 

pkg/kubectl/resource/result.go

@@ -98,7 +98,10 @@ func (r *Result) Infos() ([]*Info, error) {
 	}
 
 	infos := []*Info{}
-	err := r.visitor.Visit(func(info *Info) error {
+	err := r.visitor.Visit(func(info *Info, err error) error {
+		if err != nil {
+			return err
+		}
 		infos = append(infos, info)
 		return nil
 	})

pkg/kubectl/resource/selector.go

@@ -68,7 +68,7 @@ func (r *Selector) Visit(fn VisitorFunc) error {
 		Object:          list,
 		ResourceVersion: resourceVersion,
 	}
-	return fn(info)
+	return fn(info, nil)
 }
 
 func (r *Selector) Watch(resourceVersion string) (watch.Interface, error) {

pkg/kubectl/resource/visitor.go

@@ -26,8 +26,6 @@ import (
 	"os"
 	"path/filepath"
 
-	"github.com/golang/glog"
-
 	"k8s.io/kubernetes/pkg/api/meta"
 	"k8s.io/kubernetes/pkg/api/validation"
 	"k8s.io/kubernetes/pkg/runtime"
@@ -39,14 +37,16 @@ import (
 const constSTDINstr string = "STDIN"
 
 // Visitor lets clients walk a list of resources.
-// TODO: we should rethink how we handle errors in the visit loop
-// (See http://pr.k8s.io/9357#issuecomment-109600305)
 type Visitor interface {
 	Visit(VisitorFunc) error
 }
 
-// VisitorFunc implements the Visitor interface for a matching function
+// VisitorFunc implements the Visitor interface for a matching function.
-type VisitorFunc func(*Info) error
+// If there was a problem walking a list of resources, the incoming error
+// will describe the problem and the function can decide how to handle that error.
+// A nil returned indicates to accept an error to continue loops even when errors happen.
+// This is useful for ignoring certain kinds of errors or aggregating errors in some way.
+type VisitorFunc func(*Info, error) error
 
 // Watchable describes a resource that can be watched for changes that occur on the server,
 // beginning after the provided resource version.
@@ -96,7 +96,7 @@ func NewInfo(client RESTClient, mapping *meta.RESTMapping, namespace, name strin
 
 // Visit implements Visitor
 func (i *Info) Visit(fn VisitorFunc) error {
-	return fn(i)
+	return fn(i, nil)
 }
 
 // Get retrieves the object from the Namespace and Name fields
@@ -180,8 +180,12 @@ type EagerVisitorList []Visitor
 func (l EagerVisitorList) Visit(fn VisitorFunc) error {
 	errs := []error(nil)
 	for i := range l {
-		if err := l[i].Visit(func(info *Info) error {
+		if err := l[i].Visit(func(info *Info, err error) error {
-			if err := fn(info); err != nil {
+			if err != nil {
+				errs = append(errs, err)
+				return nil
+			}
+			if err := fn(info, nil); err != nil {
 				errs = append(errs, err)
 			}
 			return nil
@@ -234,7 +238,7 @@ func (v *URLVisitor) Visit(fn VisitorFunc) error {
 	if err != nil {
 		return err
 	}
-	return fn(info)
+	return fn(info, nil)
 }
 
 // DecoratedVisitor will invoke the decorators in order prior to invoking the visitor function
@@ -256,13 +260,16 @@ func NewDecoratedVisitor(v Visitor, fn ...VisitorFunc) Visitor {
 
 // Visit implements Visitor
 func (v DecoratedVisitor) Visit(fn VisitorFunc) error {
-	return v.visitor.Visit(func(info *Info) error {
+	return v.visitor.Visit(func(info *Info, err error) error {
+		if err != nil {
+			return err
+		}
 		for i := range v.decorators {
-			if err := v.decorators[i](info); err != nil {
+			if err := v.decorators[i](info, nil); err != nil {
 				return err
 			}
 		}
-		return fn(info)
+		return fn(info, nil)
 	})
 }
 
@@ -281,8 +288,12 @@ type ContinueOnErrorVisitor struct {
 // not being visited.
 func (v ContinueOnErrorVisitor) Visit(fn VisitorFunc) error {
 	errs := []error{}
-	err := v.Visitor.Visit(func(info *Info) error {
+	err := v.Visitor.Visit(func(info *Info, err error) error {
-		if err := fn(info); err != nil {
+		if err != nil {
+			errs = append(errs, err)
+			return nil
+		}
+		if err := fn(info, nil); err != nil {
 			errs = append(errs, err)
 		}
 		return nil
@@ -314,13 +325,16 @@ func NewFlattenListVisitor(v Visitor, mapper *Mapper) Visitor {
 }
 
 func (v FlattenListVisitor) Visit(fn VisitorFunc) error {
-	return v.Visitor.Visit(func(info *Info) error {
+	return v.Visitor.Visit(func(info *Info, err error) error {
+		if err != nil {
+			return err
+		}
 		if info.Object == nil {
-			return fn(info)
+			return fn(info, nil)
 		}
 		items, err := runtime.ExtractList(info.Object)
 		if err != nil {
-			return fn(info)
+			return fn(info, nil)
 		}
 		if errs := runtime.DecodeList(items, struct {
 			runtime.ObjectTyper
@@ -336,7 +350,7 @@ func (v FlattenListVisitor) Visit(fn VisitorFunc) error {
 			if len(info.ResourceVersion) != 0 {
 				item.ResourceVersion = info.ResourceVersion
 			}
-			if err := fn(item); err != nil {
+			if err := fn(item, nil); err != nil {
 				return err
 			}
 		}
@@ -358,17 +372,17 @@ func ignoreFile(path string, extensions []string) bool {
 }
 
 // FileVisitorForSTDIN return a special FileVisitor just for STDIN
-func FileVisitorForSTDIN(mapper *Mapper, ignoreErrors bool, schema validation.Schema) Visitor {
+func FileVisitorForSTDIN(mapper *Mapper, schema validation.Schema) Visitor {
 	return &FileVisitor{
 		Path:          constSTDINstr,
-		StreamVisitor: NewStreamVisitor(nil, mapper, constSTDINstr, ignoreErrors, schema),
+		StreamVisitor: NewStreamVisitor(nil, mapper, constSTDINstr, schema),
 	}
 }
 
 // ExpandPathsToFileVisitors will return a slice of FileVisitors that will handle files from the provided path.
 // After FileVisitors open the files, they will pass a io.Reader to a StreamVisitor to do the reading. (stdin
 // is also taken care of). Paths argument also accepts a single file, and will return a single visitor
-func ExpandPathsToFileVisitors(mapper *Mapper, paths string, recursive bool, extensions []string, ignoreErrors bool, schema validation.Schema) ([]Visitor, error) {
+func ExpandPathsToFileVisitors(mapper *Mapper, paths string, recursive bool, extensions []string, schema validation.Schema) ([]Visitor, error) {
 	var visitors []Visitor
 	err := filepath.Walk(paths, func(path string, fi os.FileInfo, err error) error {
 		if err != nil {
@@ -388,7 +402,7 @@ func ExpandPathsToFileVisitors(mapper *Mapper, paths string, recursive bool, ext
 
 		visitor := &FileVisitor{
 			Path:          path,
-			StreamVisitor: NewStreamVisitor(nil, mapper, path, ignoreErrors, schema),
+			StreamVisitor: NewStreamVisitor(nil, mapper, path, schema),
 		}
 
 		visitors = append(visitors, visitor)
@@ -433,17 +447,15 @@ type StreamVisitor struct {
 	*Mapper
 
 	Source string
-	IgnoreErrors bool
 	Schema validation.Schema
 }
 
 // NewStreamVisitor is a helper function that is useful when we want to change the fields of the struct but keep calls the same.
-func NewStreamVisitor(r io.Reader, mapper *Mapper, source string, ignoreErrors bool, schema validation.Schema) *StreamVisitor {
+func NewStreamVisitor(r io.Reader, mapper *Mapper, source string, schema validation.Schema) *StreamVisitor {
 	return &StreamVisitor{
 		Reader: r,
 		Mapper: mapper,
 		Source: source,
-		IgnoreErrors: ignoreErrors,
 		Schema: schema,
 	}
 }
@@ -468,20 +480,21 @@ func (v *StreamVisitor) Visit(fn VisitorFunc) error {
 		}
 		info, err := v.InfoForData(ext.RawJSON, v.Source)
 		if err != nil {
-			if v.IgnoreErrors {
+			if fnErr := fn(info, err); fnErr != nil {
-				fmt.Fprintf(os.Stderr, "error: could not read an encoded object: %v\n", err)
+				return fnErr
-				glog.V(4).Infof("Unreadable: %s", string(ext.RawJSON))
+			}
 			continue
 		}
-			return err
+		if err := fn(info, nil); err != nil {
-		}
-		if err := fn(info); err != nil {
 			return err
 		}
 	}
 }
 
-func UpdateObjectNamespace(info *Info) error {
+func UpdateObjectNamespace(info *Info, err error) error {
+	if err != nil {
+		return err
+	}
 	if info.Object != nil {
 		return info.Mapping.MetadataAccessor.SetNamespace(info.Object, info.Namespace)
 	}
@@ -489,10 +502,13 @@ func UpdateObjectNamespace(info *Info) error {
 }
 
 // FilterNamespace omits the namespace if the object is not namespace scoped
-func FilterNamespace(info *Info) error {
+func FilterNamespace(info *Info, err error) error {
+	if err != nil {
+		return err
+	}
 	if !info.Namespaced() {
 		info.Namespace = ""
-		UpdateObjectNamespace(info)
+		UpdateObjectNamespace(info, nil)
 	}
 	return nil
 }
@@ -500,13 +516,16 @@ func FilterNamespace(info *Info) error {
 // SetNamespace ensures that every Info object visited will have a namespace
 // set. If info.Object is set, it will be mutated as well.
 func SetNamespace(namespace string) VisitorFunc {
-	return func(info *Info) error {
+	return func(info *Info, err error) error {
+		if err != nil {
+			return err
+		}
 		if !info.Namespaced() {
 			return nil
 		}
 		if len(info.Namespace) == 0 {
 			info.Namespace = namespace
-			UpdateObjectNamespace(info)
+			UpdateObjectNamespace(info, nil)
 		}
 		return nil
 	}
@@ -517,13 +536,16 @@ func SetNamespace(namespace string) VisitorFunc {
 // value, returns an error. This is intended to guard against administrators
 // accidentally operating on resources outside their namespace.
 func RequireNamespace(namespace string) VisitorFunc {
-	return func(info *Info) error {
+	return func(info *Info, err error) error {
+		if err != nil {
+			return err
+		}
 		if !info.Namespaced() {
 			return nil
 		}
 		if len(info.Namespace) == 0 {
 			info.Namespace = namespace
-			UpdateObjectNamespace(info)
+			UpdateObjectNamespace(info, nil)
 			return nil
 		}
 		if info.Namespace != namespace {
@@ -535,7 +557,10 @@ func RequireNamespace(namespace string) VisitorFunc {
 
 // RetrieveLatest updates the Object on each Info by invoking a standard client
 // Get.
-func RetrieveLatest(info *Info) error {
+func RetrieveLatest(info *Info, err error) error {
+	if err != nil {
+		return err
+	}
 	if len(info.Name) == 0 {
 		return nil
 	}
@@ -552,7 +577,10 @@ func RetrieveLatest(info *Info) error {
 }
 
 // RetrieveLazy updates the object if it has not been loaded yet.
-func RetrieveLazy(info *Info) error {
+func RetrieveLazy(info *Info, err error) error {
+	if err != nil {
+		return err
+	}
 	if info.Object == nil {
 		return info.Get()
 	}