diff options
Diffstat (limited to 'vendor/k8s.io/client-go/discovery/discovery_client.go')
| -rw-r--r-- | vendor/k8s.io/client-go/discovery/discovery_client.go | 455 |
1 files changed, 455 insertions, 0 deletions
diff --git a/vendor/k8s.io/client-go/discovery/discovery_client.go b/vendor/k8s.io/client-go/discovery/discovery_client.go new file mode 100644 index 000000000..011dd9ecf --- /dev/null +++ b/vendor/k8s.io/client-go/discovery/discovery_client.go @@ -0,0 +1,455 @@ +/* +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/emicklei/go-restful-swagger12" + + "github.com/go-openapi/loads" + "github.com/go-openapi/spec" + "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" + "k8s.io/client-go/pkg/api/v1" + 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 + SwaggerSchemaInterface + OpenAPISchemaInterface +} + +// CachedDiscoveryInterface is a DiscoveryInterface with cache invalidation and freshness. +type CachedDiscoveryInterface interface { + DiscoveryInterface + // Fresh returns true if no cached data was used that had been retrieved before the instantiation. + 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) +} + +// SwaggerSchemaInterface has a method to retrieve the swagger schema. +type SwaggerSchemaInterface interface { + // SwaggerSchema retrieves and parses the swagger API schema the server supports. + SwaggerSchema(version schema.GroupVersion) (*swagger.ApiDeclaration, 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() (*spec.Swagger, 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 +} + +// SwaggerSchema retrieves and parses the swagger API schema the server supports. +// TODO: Replace usages with Open API. Tracked in https://github.com/kubernetes/kubernetes/issues/44589 +func (d *DiscoveryClient) SwaggerSchema(version schema.GroupVersion) (*swagger.ApiDeclaration, error) { + if version.Empty() { + return nil, fmt.Errorf("groupVersion cannot be empty") + } + + groupList, err := d.ServerGroups() + if err != nil { + return nil, err + } + groupVersions := metav1.ExtractGroupVersions(groupList) + // This check also takes care the case that kubectl is newer than the running endpoint + if stringDoesntExistIn(version.String(), groupVersions) { + return nil, fmt.Errorf("API version: %v is not supported by the server. Use one of: %v", version, groupVersions) + } + var path string + if len(d.LegacyPrefix) > 0 && version == v1.SchemeGroupVersion { + path = "/swaggerapi" + d.LegacyPrefix + "/" + version.Version + } else { + path = "/swaggerapi/apis/" + version.Group + "/" + version.Version + } + + body, err := d.restClient.Get().AbsPath(path).Do().Raw() + if err != nil { + return nil, err + } + var schema swagger.ApiDeclaration + err = json.Unmarshal(body, &schema) + if err != nil { + return nil, fmt.Errorf("got '%s': %v", string(body), err) + } + return &schema, nil +} + +// OpenAPISchema fetches the open api schema using a rest client and parses the json. +// Warning: this is very expensive (~1.2s) +func (d *DiscoveryClient) OpenAPISchema() (*spec.Swagger, error) { + data, err := d.restClient.Get().AbsPath("/swagger.json").Do().Raw() + if err != nil { + return nil, err + } + msg := json.RawMessage(data) + doc, err := loads.Analyzed(msg, "") + if err != nil { + return nil, err + } + return doc.Spec(), err +} + +// 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 +} + +// NewDiscoveryClientForConfig 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 + +} + +// New creates 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 +} |