Merge pull request #77819 from smarterclayton/client

Add a metadata client to client-go that can read PartialObjectMetadata

Kubernetes-commit: 024c7bd84f1e9a386778e14068f57c3b1e193565

metadata/interface.go

@@ -0,0 +1,47 @@
+/*
+Copyright 2016 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 metadata
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/watch"
+)
+
+// Interface allows a caller to get the metadata (in the form of PartialObjectMetadata objects)
+// from any Kubernetes compatible resource API.
+type Interface interface {
+	Resource(resource schema.GroupVersionResource) Getter
+}
+
+// ResourceInterface contains the set of methods that may be invoked on objects by their metadata.
+// Update is not supported by the server, but Patch can be used for the actions Update would handle.
+type ResourceInterface interface {
+	Delete(name string, options *metav1.DeleteOptions, subresources ...string) error
+	DeleteCollection(options *metav1.DeleteOptions, listOptions metav1.ListOptions) error
+	Get(name string, options metav1.GetOptions, subresources ...string) (*metav1.PartialObjectMetadata, error)
+	List(opts metav1.ListOptions) (*metav1.PartialObjectMetadataList, error)
+	Watch(opts metav1.ListOptions) (watch.Interface, error)
+	Patch(name string, pt types.PatchType, data []byte, options metav1.PatchOptions, subresources ...string) (*metav1.PartialObjectMetadata, error)
+}
+
+// Getter handles both namespaced and non-namespaced resource types consistently.
+type Getter interface {
+	Namespace(string) ResourceInterface
+	ResourceInterface
+}

metadata/metadata.go

@@ -0,0 +1,312 @@
+/*
+Copyright 2018 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 metadata
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"k8s.io/klog"
+
+	metainternalversion "k8s.io/apimachinery/pkg/apis/meta/internalversion"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/watch"
+	"k8s.io/client-go/rest"
+)
+
+var deleteScheme = runtime.NewScheme()
+var parameterScheme = runtime.NewScheme()
+var deleteOptionsCodec = serializer.NewCodecFactory(deleteScheme)
+var dynamicParameterCodec = runtime.NewParameterCodec(parameterScheme)
+
+var versionV1 = schema.GroupVersion{Version: "v1"}
+
+func init() {
+	metav1.AddToGroupVersion(parameterScheme, versionV1)
+	metav1.AddToGroupVersion(deleteScheme, versionV1)
+}
+
+// Client allows callers to retrieve the object metadata for any
+// Kubernetes-compatible API endpoint. The client uses the
+// meta.k8s.io/v1 PartialObjectMetadata resource to more efficiently
+// retrieve just the necessary metadata, but on older servers
+// (Kubernetes 1.14 and before) will retrieve the object and then
+// convert the metadata.
+type Client struct {
+	client *rest.RESTClient
+}
+
+var _ Interface = &Client{}
+
+// ConfigFor returns a copy of the provided config with the
+// appropriate metadata client defaults set.
+func ConfigFor(inConfig *rest.Config) *rest.Config {
+	config := rest.CopyConfig(inConfig)
+	config.AcceptContentTypes = "application/vnd.kubernetes.protobuf,application/json"
+	config.ContentType = "application/vnd.kubernetes.protobuf"
+	config.NegotiatedSerializer = metainternalversion.Codecs.WithoutConversion()
+	if config.UserAgent == "" {
+		config.UserAgent = rest.DefaultKubernetesUserAgent()
+	}
+	return config
+}
+
+// NewConfigOrDie creates a new metadata client for the given config and
+// panics if there is an error in the config.
+func NewConfigOrDie(c *rest.Config) Interface {
+	ret, err := NewForConfig(c)
+	if err != nil {
+		panic(err)
+	}
+	return ret
+}
+
+// NewForConfig creates a new metadata client that can retrieve object
+// metadata details about any Kubernetes object (core, aggregated, or custom
+// resource based) in the form of PartialObjectMetadata objects, or returns
+// an error.
+func NewForConfig(inConfig *rest.Config) (Interface, error) {
+	config := ConfigFor(inConfig)
+	// for serializing the options
+	config.GroupVersion = &schema.GroupVersion{}
+	config.APIPath = "/this-value-should-never-be-sent"
+
+	restClient, err := rest.RESTClientFor(config)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Client{client: restClient}, nil
+}
+
+type client struct {
+	client    *Client
+	namespace string
+	resource  schema.GroupVersionResource
+}
+
+// Resource returns an interface that can access cluster or namespace
+// scoped instances of resource.
+func (c *Client) Resource(resource schema.GroupVersionResource) Getter {
+	return &client{client: c, resource: resource}
+}
+
+// Namespace returns an interface that can access namespace-scoped instances of the
+// provided resource.
+func (c *client) Namespace(ns string) ResourceInterface {
+	ret := *c
+	ret.namespace = ns
+	return &ret
+}
+
+// Delete removes the provided resource from the server.
+func (c *client) Delete(name string, opts *metav1.DeleteOptions, subresources ...string) error {
+	if len(name) == 0 {
+		return fmt.Errorf("name is required")
+	}
+	if opts == nil {
+		opts = &metav1.DeleteOptions{}
+	}
+	deleteOptionsByte, err := runtime.Encode(deleteOptionsCodec.LegacyCodec(schema.GroupVersion{Version: "v1"}), opts)
+	if err != nil {
+		return err
+	}
+
+	result := c.client.client.
+		Delete().
+		AbsPath(append(c.makeURLSegments(name), subresources...)...).
+		Body(deleteOptionsByte).
+		Do()
+	return result.Error()
+}
+
+// DeleteCollection triggers deletion of all resources in the specified scope (namespace or cluster).
+func (c *client) DeleteCollection(opts *metav1.DeleteOptions, listOptions metav1.ListOptions) error {
+	if opts == nil {
+		opts = &metav1.DeleteOptions{}
+	}
+	deleteOptionsByte, err := runtime.Encode(deleteOptionsCodec.LegacyCodec(schema.GroupVersion{Version: "v1"}), opts)
+	if err != nil {
+		return err
+	}
+
+	result := c.client.client.
+		Delete().
+		AbsPath(c.makeURLSegments("")...).
+		Body(deleteOptionsByte).
+		SpecificallyVersionedParams(&listOptions, dynamicParameterCodec, versionV1).
+		Do()
+	return result.Error()
+}
+
+// Get returns the resource with name from the specified scope (namespace or cluster).
+func (c *client) Get(name string, opts metav1.GetOptions, subresources ...string) (*metav1.PartialObjectMetadata, error) {
+	if len(name) == 0 {
+		return nil, fmt.Errorf("name is required")
+	}
+	result := c.client.client.Get().AbsPath(append(c.makeURLSegments(name), subresources...)...).
+		SetHeader("Accept", "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json").
+		SpecificallyVersionedParams(&opts, dynamicParameterCodec, versionV1).
+		Do()
+	if err := result.Error(); err != nil {
+		return nil, err
+	}
+	obj, err := result.Get()
+	if runtime.IsNotRegisteredError(err) {
+		klog.V(5).Infof("Unable to retrieve PartialObjectMetadata: %#v", err)
+		rawBytes, err := result.Raw()
+		if err != nil {
+			return nil, err
+		}
+		var partial metav1.PartialObjectMetadata
+		if err := json.Unmarshal(rawBytes, &partial); err != nil {
+			return nil, fmt.Errorf("unable to decode returned object as PartialObjectMetadata: %v", err)
+		}
+		if !isLikelyObjectMetadata(&partial) {
+			return nil, fmt.Errorf("object does not appear to match the ObjectMeta schema: %#v", partial)
+		}
+		partial.TypeMeta = metav1.TypeMeta{}
+		return &partial, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	partial, ok := obj.(*metav1.PartialObjectMetadata)
+	if !ok {
+		return nil, fmt.Errorf("unexpected object, expected PartialObjectMetadata but got %T", obj)
+	}
+	return partial, nil
+}
+
+// List returns all resources within the specified scope (namespace or cluster).
+func (c *client) List(opts metav1.ListOptions) (*metav1.PartialObjectMetadataList, error) {
+	result := c.client.client.Get().AbsPath(c.makeURLSegments("")...).
+		SetHeader("Accept", "application/vnd.kubernetes.protobuf;as=PartialObjectMetadataList;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadataList;g=meta.k8s.io;v=v1,application/json").
+		SpecificallyVersionedParams(&opts, dynamicParameterCodec, versionV1).
+		Do()
+	if err := result.Error(); err != nil {
+		return nil, err
+	}
+	obj, err := result.Get()
+	if runtime.IsNotRegisteredError(err) {
+		klog.V(5).Infof("Unable to retrieve PartialObjectMetadataList: %#v", err)
+		rawBytes, err := result.Raw()
+		if err != nil {
+			return nil, err
+		}
+		var partial metav1.PartialObjectMetadataList
+		if err := json.Unmarshal(rawBytes, &partial); err != nil {
+			return nil, fmt.Errorf("unable to decode returned object as PartialObjectMetadataList: %v", err)
+		}
+		partial.TypeMeta = metav1.TypeMeta{}
+		return &partial, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	partial, ok := obj.(*metav1.PartialObjectMetadataList)
+	if !ok {
+		return nil, fmt.Errorf("unexpected object, expected PartialObjectMetadata but got %T", obj)
+	}
+	return partial, nil
+}
+
+// Watch finds all changes to the resources in the specified scope (namespace or cluster).
+func (c *client) Watch(opts metav1.ListOptions) (watch.Interface, error) {
+	var timeout time.Duration
+	if opts.TimeoutSeconds != nil {
+		timeout = time.Duration(*opts.TimeoutSeconds) * time.Second
+	}
+	opts.Watch = true
+	return c.client.client.Get().
+		AbsPath(c.makeURLSegments("")...).
+		SetHeader("Accept", "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json").
+		SpecificallyVersionedParams(&opts, dynamicParameterCodec, versionV1).
+		Timeout(timeout).
+		Watch()
+}
+
+// Patch modifies the named resource in the specified scope (namespace or cluster).
+func (c *client) Patch(name string, pt types.PatchType, data []byte, opts metav1.PatchOptions, subresources ...string) (*metav1.PartialObjectMetadata, error) {
+	if len(name) == 0 {
+		return nil, fmt.Errorf("name is required")
+	}
+	result := c.client.client.
+		Patch(pt).
+		AbsPath(append(c.makeURLSegments(name), subresources...)...).
+		Body(data).
+		SetHeader("Accept", "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json").
+		SpecificallyVersionedParams(&opts, dynamicParameterCodec, versionV1).
+		Do()
+	if err := result.Error(); err != nil {
+		return nil, err
+	}
+	obj, err := result.Get()
+	if runtime.IsNotRegisteredError(err) {
+		rawBytes, err := result.Raw()
+		if err != nil {
+			return nil, err
+		}
+		var partial metav1.PartialObjectMetadata
+		if err := json.Unmarshal(rawBytes, &partial); err != nil {
+			return nil, fmt.Errorf("unable to decode returned object as PartialObjectMetadata: %v", err)
+		}
+		if !isLikelyObjectMetadata(&partial) {
+			return nil, fmt.Errorf("object does not appear to match the ObjectMeta schema")
+		}
+		partial.TypeMeta = metav1.TypeMeta{}
+		return &partial, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	partial, ok := obj.(*metav1.PartialObjectMetadata)
+	if !ok {
+		return nil, fmt.Errorf("unexpected object, expected PartialObjectMetadata but got %T", obj)
+	}
+	return partial, nil
+}
+
+func (c *client) makeURLSegments(name string) []string {
+	url := []string{}
+	if len(c.resource.Group) == 0 {
+		url = append(url, "api")
+	} else {
+		url = append(url, "apis", c.resource.Group)
+	}
+	url = append(url, c.resource.Version)
+
+	if len(c.namespace) > 0 {
+		url = append(url, "namespaces", c.namespace)
+	}
+	url = append(url, c.resource.Resource)
+
+	if len(name) > 0 {
+		url = append(url, name)
+	}
+
+	return url
+}
+
+func isLikelyObjectMetadata(meta *metav1.PartialObjectMetadata) bool {
+	return len(meta.UID) > 0 || !meta.CreationTimestamp.IsZero() || len(meta.Name) > 0 || len(meta.GenerateName) > 0
+}

metadata/metadata_test.go

@@ -0,0 +1,243 @@
+/*
+Copyright 2019 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 metadata
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"reflect"
+	"strings"
+	"testing"
+
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/util/diff"
+	"k8s.io/client-go/rest"
+)
+
+func TestClient(t *testing.T) {
+	gvr := schema.GroupVersionResource{Group: "group", Version: "v1", Resource: "resource"}
+
+	writeJSON := func(t *testing.T, w http.ResponseWriter, obj runtime.Object) {
+		data, err := json.Marshal(obj)
+		if err != nil {
+			t.Fatal(err)
+		}
+		w.Header().Set("Content-Type", "application/json")
+		if _, err := w.Write(data); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	testCases := []struct {
+		name    string
+		handler func(t *testing.T, w http.ResponseWriter, req *http.Request)
+		want    func(t *testing.T, client *Client)
+	}{
+		{
+			name: "GET is able to convert a JSON object to PartialObjectMetadata",
+			handler: func(t *testing.T, w http.ResponseWriter, req *http.Request) {
+				if req.Header.Get("Accept") != "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json" {
+					t.Fatal(req.Header.Get("Accept"))
+				}
+				if req.Method != "GET" && req.URL.String() != "/apis/group/v1/namespaces/ns/resource/name" {
+					t.Fatal(req.URL.String())
+				}
+				writeJSON(t, w, &corev1.Pod{
+					TypeMeta: metav1.TypeMeta{
+						Kind:       "Pod",
+						APIVersion: "v1",
+					},
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "name",
+						Namespace: "ns",
+					},
+				})
+			},
+			want: func(t *testing.T, client *Client) {
+				obj, err := client.Resource(gvr).Namespace("ns").Get("name", metav1.GetOptions{})
+				if err != nil {
+					t.Fatal(err)
+				}
+				expect := &metav1.PartialObjectMetadata{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "name",
+						Namespace: "ns",
+					},
+				}
+				if !reflect.DeepEqual(expect, obj) {
+					t.Fatal(diff.ObjectReflectDiff(expect, obj))
+				}
+			},
+		},
+
+		{
+			name: "LIST is able to convert a JSON object to PartialObjectMetadata",
+			handler: func(t *testing.T, w http.ResponseWriter, req *http.Request) {
+				if req.Header.Get("Accept") != "application/vnd.kubernetes.protobuf;as=PartialObjectMetadataList;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadataList;g=meta.k8s.io;v=v1,application/json" {
+					t.Fatal(req.Header.Get("Accept"))
+				}
+				if req.Method != "GET" && req.URL.String() != "/apis/group/v1/namespaces/ns/resource" {
+					t.Fatal(req.URL.String())
+				}
+				writeJSON(t, w, &corev1.PodList{
+					TypeMeta: metav1.TypeMeta{
+						Kind:       "PodList",
+						APIVersion: "v1",
+					},
+					ListMeta: metav1.ListMeta{
+						ResourceVersion: "253",
+					},
+					Items: []corev1.Pod{
+						{
+							TypeMeta: metav1.TypeMeta{
+								Kind:       "Pod",
+								APIVersion: "v1",
+							},
+							ObjectMeta: metav1.ObjectMeta{
+								Name:      "name",
+								Namespace: "ns",
+							},
+						},
+					},
+				})
+			},
+			want: func(t *testing.T, client *Client) {
+				objs, err := client.Resource(gvr).Namespace("ns").List(metav1.ListOptions{})
+				if err != nil {
+					t.Fatal(err)
+				}
+				if objs.GetResourceVersion() != "253" {
+					t.Fatal(objs)
+				}
+				expect := []metav1.PartialObjectMetadata{
+					{
+						TypeMeta: metav1.TypeMeta{
+							Kind:       "Pod",
+							APIVersion: "v1",
+						},
+						ObjectMeta: metav1.ObjectMeta{
+							Name:      "name",
+							Namespace: "ns",
+						},
+					},
+				}
+				if !reflect.DeepEqual(expect, objs.Items) {
+					t.Fatal(diff.ObjectReflectDiff(expect, objs.Items))
+				}
+			},
+		},
+
+		{
+			name: "GET fails if the object is JSON and has no kind",
+			handler: func(t *testing.T, w http.ResponseWriter, req *http.Request) {
+				if req.Header.Get("Accept") != "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json" {
+					t.Fatal(req.Header.Get("Accept"))
+				}
+				if req.Method != "GET" && req.URL.String() != "/apis/group/v1/namespaces/ns/resource/name" {
+					t.Fatal(req.URL.String())
+				}
+				writeJSON(t, w, &corev1.Pod{
+					TypeMeta: metav1.TypeMeta{},
+					ObjectMeta: metav1.ObjectMeta{
+						UID: "123",
+					},
+				})
+			},
+			want: func(t *testing.T, client *Client) {
+				obj, err := client.Resource(gvr).Namespace("ns").Get("name", metav1.GetOptions{})
+				if err == nil || !runtime.IsMissingKind(err) {
+					t.Fatal(err)
+				}
+				if obj != nil {
+					t.Fatal(obj)
+				}
+			},
+		},
+
+		{
+			name: "GET fails if the object is JSON and has no apiVersion",
+			handler: func(t *testing.T, w http.ResponseWriter, req *http.Request) {
+				if req.Header.Get("Accept") != "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json" {
+					t.Fatal(req.Header.Get("Accept"))
+				}
+				if req.Method != "GET" && req.URL.String() != "/apis/group/v1/namespaces/ns/resource/name" {
+					t.Fatal(req.URL.String())
+				}
+				writeJSON(t, w, &corev1.Pod{
+					TypeMeta: metav1.TypeMeta{
+						Kind: "Pod",
+					},
+					ObjectMeta: metav1.ObjectMeta{
+						UID: "123",
+					},
+				})
+			},
+			want: func(t *testing.T, client *Client) {
+				obj, err := client.Resource(gvr).Namespace("ns").Get("name", metav1.GetOptions{})
+				if err == nil || !runtime.IsMissingVersion(err) {
+					t.Fatal(err)
+				}
+				if obj != nil {
+					t.Fatal(obj)
+				}
+			},
+		},
+
+		{
+			name: "GET fails if the object is JSON and not clearly metadata",
+			handler: func(t *testing.T, w http.ResponseWriter, req *http.Request) {
+				if req.Header.Get("Accept") != "application/vnd.kubernetes.protobuf;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json;as=PartialObjectMetadata;g=meta.k8s.io;v=v1,application/json" {
+					t.Fatal(req.Header.Get("Accept"))
+				}
+				if req.Method != "GET" && req.URL.String() != "/apis/group/v1/namespaces/ns/resource/name" {
+					t.Fatal(req.URL.String())
+				}
+				writeJSON(t, w, &corev1.Pod{
+					TypeMeta: metav1.TypeMeta{
+						Kind:       "Pod",
+						APIVersion: "v1",
+					},
+					ObjectMeta: metav1.ObjectMeta{},
+				})
+			},
+			want: func(t *testing.T, client *Client) {
+				obj, err := client.Resource(gvr).Namespace("ns").Get("name", metav1.GetOptions{})
+				if err == nil || !strings.Contains(err.Error(), "object does not appear to match the ObjectMeta schema") {
+					t.Fatal(err)
+				}
+				if obj != nil {
+					t.Fatal(obj)
+				}
+			},
+		},
+	}
+
+	for _, tt := range testCases {
+		t.Run(tt.name, func(t *testing.T) {
+			s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { tt.handler(t, w, req) }))
+			defer s.Close()
+
+			cfg := ConfigFor(&rest.Config{Host: s.URL})
+			client := NewConfigOrDie(cfg).(*Client)
+			tt.want(t, client)
+		})
+	}
+}