vendor files

vendor/k8s.io/kubernetes/pkg/kubectl/resource/result.go

@@ -0,0 +1,241 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resource
+
+import (
+	"fmt"
+	"reflect"
+
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/meta"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	utilerrors "k8s.io/apimachinery/pkg/util/errors"
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/apimachinery/pkg/watch"
+)
+
+// ErrMatchFunc can be used to filter errors that may not be true failures.
+type ErrMatchFunc func(error) bool
+
+// Result contains helper methods for dealing with the outcome of a Builder.
+type Result struct {
+	err     error
+	visitor Visitor
+
+	sources            []Visitor
+	singleItemImplied  bool
+	targetsSingleItems bool
+
+	mapper       *Mapper
+	ignoreErrors []utilerrors.Matcher
+
+	// populated by a call to Infos
+	info []*Info
+}
+
+// withError allows a fluent style for internal result code.
+func (r *Result) withError(err error) *Result {
+	r.err = err
+	return r
+}
+
+// TargetsSingleItems returns true if any of the builder arguments pointed
+// to non-list calls (if the user explicitly asked for any object by name).
+// This includes directories, streams, URLs, and resource name tuples.
+func (r *Result) TargetsSingleItems() bool {
+	return r.targetsSingleItems
+}
+
+// IgnoreErrors will filter errors that occur when by visiting the result
+// (but not errors that occur by creating the result in the first place),
+// eliminating any that match fns. This is best used in combination with
+// Builder.ContinueOnError(), where the visitors accumulate errors and return
+// them after visiting as a slice of errors. If no errors remain after
+// filtering, the various visitor methods on Result will return nil for
+// err.
+func (r *Result) IgnoreErrors(fns ...ErrMatchFunc) *Result {
+	for _, fn := range fns {
+		r.ignoreErrors = append(r.ignoreErrors, utilerrors.Matcher(fn))
+	}
+	return r
+}
+
+// Mapper returns a copy of the builder's mapper.
+func (r *Result) Mapper() *Mapper {
+	return r.mapper
+}
+
+// Err returns one or more errors (via a util.ErrorList) that occurred prior
+// to visiting the elements in the visitor. To see all errors including those
+// that occur during visitation, invoke Infos().
+func (r *Result) Err() error {
+	return r.err
+}
+
+// Visit implements the Visitor interface on the items described in the Builder.
+// Note that some visitor sources are not traversable more than once, or may
+// return different results.  If you wish to operate on the same set of resources
+// multiple times, use the Infos() method.
+func (r *Result) Visit(fn VisitorFunc) error {
+	if r.err != nil {
+		return r.err
+	}
+	err := r.visitor.Visit(fn)
+	return utilerrors.FilterOut(err, r.ignoreErrors...)
+}
+
+// IntoSingleItemImplied sets the provided boolean pointer to true if the Builder input
+// implies a single item, or multiple.
+func (r *Result) IntoSingleItemImplied(b *bool) *Result {
+	*b = r.singleItemImplied
+	return r
+}
+
+// Infos returns an array of all of the resource infos retrieved via traversal.
+// Will attempt to traverse the entire set of visitors only once, and will return
+// a cached list on subsequent calls.
+func (r *Result) Infos() ([]*Info, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.info != nil {
+		return r.info, nil
+	}
+
+	infos := []*Info{}
+	err := r.visitor.Visit(func(info *Info, err error) error {
+		if err != nil {
+			return err
+		}
+		infos = append(infos, info)
+		return nil
+	})
+	err = utilerrors.FilterOut(err, r.ignoreErrors...)
+
+	r.info, r.err = infos, err
+	return infos, err
+}
+
+// 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
+// v1.List. The ResourceVersion of the v1.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 toV1List(objects, version), err
+}
+
+// Compile time check to enforce that list implements the necessary interface
+var _ metav1.ListInterface = &v1.List{}
+var _ metav1.ListMetaAccessor = &v1.List{}
+
+// toV1List takes a slice of Objects + their version, and returns
+// a v1.List Object containing the objects in the Items field
+func toV1List(objects []runtime.Object, version string) runtime.Object {
+	raw := []runtime.RawExtension{}
+	for _, o := range objects {
+		raw = append(raw, runtime.RawExtension{Object: o})
+	}
+	return &v1.List{
+		ListMeta: metav1.ListMeta{
+			ResourceVersion: version,
+		},
+		Items: raw,
+	}
+}
+
+// ResourceMapping returns a single meta.RESTMapping representing the
+// resources located by the builder, or an error if more than one
+// mapping was found.
+func (r *Result) ResourceMapping() (*meta.RESTMapping, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	mappings := map[string]*meta.RESTMapping{}
+	for i := range r.sources {
+		m, ok := r.sources[i].(ResourceMapping)
+		if !ok {
+			return nil, fmt.Errorf("a resource mapping could not be loaded from %v", reflect.TypeOf(r.sources[i]))
+		}
+		mapping := m.ResourceMapping()
+		mappings[mapping.Resource] = mapping
+	}
+	if len(mappings) != 1 {
+		return nil, fmt.Errorf("expected only a single resource type")
+	}
+	for _, mapping := range mappings {
+		return mapping, nil
+	}
+	return nil, nil
+}
+
+// Watch retrieves changes that occur on the server to the specified resource.
+// It currently supports watching a single source - if the resource source
+// (selectors or pure types) can be watched, they will be, otherwise the list
+// will be visited (equivalent to the Infos() call) and if there is a single
+// resource present, it will be watched, otherwise an error will be returned.
+func (r *Result) Watch(resourceVersion string) (watch.Interface, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if len(r.sources) != 1 {
+		return nil, fmt.Errorf("you may only watch a single resource or type of resource at a time")
+	}
+	w, ok := r.sources[0].(Watchable)
+	if !ok {
+		info, err := r.Infos()
+		if err != nil {
+			return nil, err
+		}
+		if len(info) != 1 {
+			return nil, fmt.Errorf("watch is only supported on individual resources and resource collections - %d resources were found", len(info))
+		}
+		return info[0].Watch(resourceVersion)
+	}
+	return w.Watch(resourceVersion)
+}