vendor files

vendor/k8s.io/client-go/discovery/discovery_client.go

@@ -0,0 +1,414 @@
+/*
+Copyright 2015 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 discovery
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/url"
+	"sort"
+	"strings"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/googleapis/gnostic/OpenAPIv2"
+
+	"k8s.io/apimachinery/pkg/api/errors"
+	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/version"
+	"k8s.io/client-go/kubernetes/scheme"
+	restclient "k8s.io/client-go/rest"
+)
+
+// defaultRetries is the number of times a resource discovery is repeated if an api group disappears on the fly (e.g. ThirdPartyResources).
+const defaultRetries = 2
+
+// DiscoveryInterface holds the methods that discover server-supported API groups,
+// versions and resources.
+type DiscoveryInterface interface {
+	RESTClient() restclient.Interface
+	ServerGroupsInterface
+	ServerResourcesInterface
+	ServerVersionInterface
+	OpenAPISchemaInterface
+}
+
+// CachedDiscoveryInterface is a DiscoveryInterface with cache invalidation and freshness.
+type CachedDiscoveryInterface interface {
+	DiscoveryInterface
+	// Fresh is supposed to tell the caller whether or not to retry if the cache
+	// fails to find something (false = retry, true = no need to retry).
+	//
+	// TODO: this needs to be revisited, this interface can't be locked properly
+	// and doesn't make a lot of sense.
+	Fresh() bool
+	// Invalidate enforces that no cached data is used in the future that is older than the current time.
+	Invalidate()
+}
+
+// ServerGroupsInterface has methods for obtaining supported groups on the API server
+type ServerGroupsInterface interface {
+	// ServerGroups returns the supported groups, with information like supported versions and the
+	// preferred version.
+	ServerGroups() (*metav1.APIGroupList, error)
+}
+
+// ServerResourcesInterface has methods for obtaining supported resources on the API server
+type ServerResourcesInterface interface {
+	// ServerResourcesForGroupVersion returns the supported resources for a group and version.
+	ServerResourcesForGroupVersion(groupVersion string) (*metav1.APIResourceList, error)
+	// ServerResources returns the supported resources for all groups and versions.
+	ServerResources() ([]*metav1.APIResourceList, error)
+	// ServerPreferredResources returns the supported resources with the version preferred by the
+	// server.
+	ServerPreferredResources() ([]*metav1.APIResourceList, error)
+	// ServerPreferredNamespacedResources returns the supported namespaced resources with the
+	// version preferred by the server.
+	ServerPreferredNamespacedResources() ([]*metav1.APIResourceList, error)
+}
+
+// ServerVersionInterface has a method for retrieving the server's version.
+type ServerVersionInterface interface {
+	// ServerVersion retrieves and parses the server's version (git version).
+	ServerVersion() (*version.Info, error)
+}
+
+// OpenAPISchemaInterface has a method to retrieve the open API schema.
+type OpenAPISchemaInterface interface {
+	// OpenAPISchema retrieves and parses the swagger API schema the server supports.
+	OpenAPISchema() (*openapi_v2.Document, error)
+}
+
+// DiscoveryClient implements the functions that discover server-supported API groups,
+// versions and resources.
+type DiscoveryClient struct {
+	restClient restclient.Interface
+
+	LegacyPrefix string
+}
+
+// Convert metav1.APIVersions to metav1.APIGroup. APIVersions is used by legacy v1, so
+// group would be "".
+func apiVersionsToAPIGroup(apiVersions *metav1.APIVersions) (apiGroup metav1.APIGroup) {
+	groupVersions := []metav1.GroupVersionForDiscovery{}
+	for _, version := range apiVersions.Versions {
+		groupVersion := metav1.GroupVersionForDiscovery{
+			GroupVersion: version,
+			Version:      version,
+		}
+		groupVersions = append(groupVersions, groupVersion)
+	}
+	apiGroup.Versions = groupVersions
+	// There should be only one groupVersion returned at /api
+	apiGroup.PreferredVersion = groupVersions[0]
+	return
+}
+
+// ServerGroups returns the supported groups, with information like supported versions and the
+// preferred version.
+func (d *DiscoveryClient) ServerGroups() (apiGroupList *metav1.APIGroupList, err error) {
+	// Get the groupVersions exposed at /api
+	v := &metav1.APIVersions{}
+	err = d.restClient.Get().AbsPath(d.LegacyPrefix).Do().Into(v)
+	apiGroup := metav1.APIGroup{}
+	if err == nil && len(v.Versions) != 0 {
+		apiGroup = apiVersionsToAPIGroup(v)
+	}
+	if err != nil && !errors.IsNotFound(err) && !errors.IsForbidden(err) {
+		return nil, err
+	}
+
+	// Get the groupVersions exposed at /apis
+	apiGroupList = &metav1.APIGroupList{}
+	err = d.restClient.Get().AbsPath("/apis").Do().Into(apiGroupList)
+	if err != nil && !errors.IsNotFound(err) && !errors.IsForbidden(err) {
+		return nil, err
+	}
+	// to be compatible with a v1.0 server, if it's a 403 or 404, ignore and return whatever we got from /api
+	if err != nil && (errors.IsNotFound(err) || errors.IsForbidden(err)) {
+		apiGroupList = &metav1.APIGroupList{}
+	}
+
+	// append the group retrieved from /api to the list if not empty
+	if len(v.Versions) != 0 {
+		apiGroupList.Groups = append(apiGroupList.Groups, apiGroup)
+	}
+	return apiGroupList, nil
+}
+
+// ServerResourcesForGroupVersion returns the supported resources for a group and version.
+func (d *DiscoveryClient) ServerResourcesForGroupVersion(groupVersion string) (resources *metav1.APIResourceList, err error) {
+	url := url.URL{}
+	if len(groupVersion) == 0 {
+		return nil, fmt.Errorf("groupVersion shouldn't be empty")
+	}
+	if len(d.LegacyPrefix) > 0 && groupVersion == "v1" {
+		url.Path = d.LegacyPrefix + "/" + groupVersion
+	} else {
+		url.Path = "/apis/" + groupVersion
+	}
+	resources = &metav1.APIResourceList{
+		GroupVersion: groupVersion,
+	}
+	err = d.restClient.Get().AbsPath(url.String()).Do().Into(resources)
+	if err != nil {
+		// ignore 403 or 404 error to be compatible with an v1.0 server.
+		if groupVersion == "v1" && (errors.IsNotFound(err) || errors.IsForbidden(err)) {
+			return resources, nil
+		}
+		return nil, err
+	}
+	return resources, nil
+}
+
+// serverResources returns the supported resources for all groups and versions.
+func (d *DiscoveryClient) serverResources() ([]*metav1.APIResourceList, error) {
+	apiGroups, err := d.ServerGroups()
+	if err != nil {
+		return nil, err
+	}
+
+	result := []*metav1.APIResourceList{}
+	failedGroups := make(map[schema.GroupVersion]error)
+
+	for _, apiGroup := range apiGroups.Groups {
+		for _, version := range apiGroup.Versions {
+			gv := schema.GroupVersion{Group: apiGroup.Name, Version: version.Version}
+			resources, err := d.ServerResourcesForGroupVersion(version.GroupVersion)
+			if err != nil {
+				// TODO: maybe restrict this to NotFound errors
+				failedGroups[gv] = err
+				continue
+			}
+
+			result = append(result, resources)
+		}
+	}
+
+	if len(failedGroups) == 0 {
+		return result, nil
+	}
+
+	return result, &ErrGroupDiscoveryFailed{Groups: failedGroups}
+}
+
+// ServerResources returns the supported resources for all groups and versions.
+func (d *DiscoveryClient) ServerResources() ([]*metav1.APIResourceList, error) {
+	return withRetries(defaultRetries, d.serverResources)
+}
+
+// ErrGroupDiscoveryFailed is returned if one or more API groups fail to load.
+type ErrGroupDiscoveryFailed struct {
+	// Groups is a list of the groups that failed to load and the error cause
+	Groups map[schema.GroupVersion]error
+}
+
+// Error implements the error interface
+func (e *ErrGroupDiscoveryFailed) Error() string {
+	var groups []string
+	for k, v := range e.Groups {
+		groups = append(groups, fmt.Sprintf("%s: %v", k, v))
+	}
+	sort.Strings(groups)
+	return fmt.Sprintf("unable to retrieve the complete list of server APIs: %s", strings.Join(groups, ", "))
+}
+
+// IsGroupDiscoveryFailedError returns true if the provided error indicates the server was unable to discover
+// a complete list of APIs for the client to use.
+func IsGroupDiscoveryFailedError(err error) bool {
+	_, ok := err.(*ErrGroupDiscoveryFailed)
+	return err != nil && ok
+}
+
+// serverPreferredResources returns the supported resources with the version preferred by the server.
+func (d *DiscoveryClient) serverPreferredResources() ([]*metav1.APIResourceList, error) {
+	serverGroupList, err := d.ServerGroups()
+	if err != nil {
+		return nil, err
+	}
+
+	result := []*metav1.APIResourceList{}
+	failedGroups := make(map[schema.GroupVersion]error)
+
+	grVersions := map[schema.GroupResource]string{}                         // selected version of a GroupResource
+	grApiResources := map[schema.GroupResource]*metav1.APIResource{}        // selected APIResource for a GroupResource
+	gvApiResourceLists := map[schema.GroupVersion]*metav1.APIResourceList{} // blueprint for a APIResourceList for later grouping
+
+	for _, apiGroup := range serverGroupList.Groups {
+		for _, version := range apiGroup.Versions {
+			groupVersion := schema.GroupVersion{Group: apiGroup.Name, Version: version.Version}
+			apiResourceList, err := d.ServerResourcesForGroupVersion(version.GroupVersion)
+			if err != nil {
+				// TODO: maybe restrict this to NotFound errors
+				failedGroups[groupVersion] = err
+				continue
+			}
+
+			// create empty list which is filled later in another loop
+			emptyApiResourceList := metav1.APIResourceList{
+				GroupVersion: version.GroupVersion,
+			}
+			gvApiResourceLists[groupVersion] = &emptyApiResourceList
+			result = append(result, &emptyApiResourceList)
+
+			for i := range apiResourceList.APIResources {
+				apiResource := &apiResourceList.APIResources[i]
+				if strings.Contains(apiResource.Name, "/") {
+					continue
+				}
+				gv := schema.GroupResource{Group: apiGroup.Name, Resource: apiResource.Name}
+				if _, ok := grApiResources[gv]; ok && version.Version != apiGroup.PreferredVersion.Version {
+					// only override with preferred version
+					continue
+				}
+				grVersions[gv] = version.Version
+				grApiResources[gv] = apiResource
+			}
+		}
+	}
+
+	// group selected APIResources according to GroupVersion into APIResourceLists
+	for groupResource, apiResource := range grApiResources {
+		version := grVersions[groupResource]
+		groupVersion := schema.GroupVersion{Group: groupResource.Group, Version: version}
+		apiResourceList := gvApiResourceLists[groupVersion]
+		apiResourceList.APIResources = append(apiResourceList.APIResources, *apiResource)
+	}
+
+	if len(failedGroups) == 0 {
+		return result, nil
+	}
+
+	return result, &ErrGroupDiscoveryFailed{Groups: failedGroups}
+}
+
+// ServerPreferredResources returns the supported resources with the version preferred by the
+// server.
+func (d *DiscoveryClient) ServerPreferredResources() ([]*metav1.APIResourceList, error) {
+	return withRetries(defaultRetries, d.serverPreferredResources)
+}
+
+// ServerPreferredNamespacedResources returns the supported namespaced resources with the
+// version preferred by the server.
+func (d *DiscoveryClient) ServerPreferredNamespacedResources() ([]*metav1.APIResourceList, error) {
+	all, err := d.ServerPreferredResources()
+	return FilteredBy(ResourcePredicateFunc(func(groupVersion string, r *metav1.APIResource) bool {
+		return r.Namespaced
+	}), all), err
+}
+
+// ServerVersion retrieves and parses the server's version (git version).
+func (d *DiscoveryClient) ServerVersion() (*version.Info, error) {
+	body, err := d.restClient.Get().AbsPath("/version").Do().Raw()
+	if err != nil {
+		return nil, err
+	}
+	var info version.Info
+	err = json.Unmarshal(body, &info)
+	if err != nil {
+		return nil, fmt.Errorf("got '%s': %v", string(body), err)
+	}
+	return &info, nil
+}
+
+// OpenAPISchema fetches the open api schema using a rest client and parses the proto.
+func (d *DiscoveryClient) OpenAPISchema() (*openapi_v2.Document, error) {
+	data, err := d.restClient.Get().AbsPath("/swagger-2.0.0.pb-v1").Do().Raw()
+	if err != nil {
+		return nil, err
+	}
+	document := &openapi_v2.Document{}
+	err = proto.Unmarshal(data, document)
+	if err != nil {
+		return nil, err
+	}
+	return document, nil
+}
+
+// withRetries retries the given recovery function in case the groups supported by the server change after ServerGroup() returns.
+func withRetries(maxRetries int, f func() ([]*metav1.APIResourceList, error)) ([]*metav1.APIResourceList, error) {
+	var result []*metav1.APIResourceList
+	var err error
+	for i := 0; i < maxRetries; i++ {
+		result, err = f()
+		if err == nil {
+			return result, nil
+		}
+		if _, ok := err.(*ErrGroupDiscoveryFailed); !ok {
+			return nil, err
+		}
+	}
+	return result, err
+}
+
+func setDiscoveryDefaults(config *restclient.Config) error {
+	config.APIPath = ""
+	config.GroupVersion = nil
+	codec := runtime.NoopEncoder{Decoder: scheme.Codecs.UniversalDecoder()}
+	config.NegotiatedSerializer = serializer.NegotiatedSerializerWrapper(runtime.SerializerInfo{Serializer: codec})
+	if len(config.UserAgent) == 0 {
+		config.UserAgent = restclient.DefaultKubernetesUserAgent()
+	}
+	return nil
+}
+
+// NewDiscoveryClientForConfig creates a new DiscoveryClient for the given config. This client
+// can be used to discover supported resources in the API server.
+func NewDiscoveryClientForConfig(c *restclient.Config) (*DiscoveryClient, error) {
+	config := *c
+	if err := setDiscoveryDefaults(&config); err != nil {
+		return nil, err
+	}
+	client, err := restclient.UnversionedRESTClientFor(&config)
+	return &DiscoveryClient{restClient: client, LegacyPrefix: "/api"}, err
+}
+
+// NewDiscoveryClientForConfigOrDie creates a new DiscoveryClient for the given config. If
+// there is an error, it panics.
+func NewDiscoveryClientForConfigOrDie(c *restclient.Config) *DiscoveryClient {
+	client, err := NewDiscoveryClientForConfig(c)
+	if err != nil {
+		panic(err)
+	}
+	return client
+
+}
+
+// NewDiscoveryClient returns  a new DiscoveryClient for the given RESTClient.
+func NewDiscoveryClient(c restclient.Interface) *DiscoveryClient {
+	return &DiscoveryClient{restClient: c, LegacyPrefix: "/api"}
+}
+
+func stringDoesntExistIn(str string, slice []string) bool {
+	for _, s := range slice {
+		if s == str {
+			return false
+		}
+	}
+	return true
+}
+
+// RESTClient returns a RESTClient that is used to communicate
+// with API server by this client implementation.
+func (c *DiscoveryClient) RESTClient() restclient.Interface {
+	if c == nil {
+		return nil
+	}
+	return c.restClient
+}