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(feat) Add auto-discovery in k8s | Adarsh

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This commit is contained in:
Adarsh K Kumar
2020-10-30 21:00:03 +05:30
parent d76caeeb35
commit 81e6e0b188
1170 changed files with 441034 additions and 14 deletions
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508
vendor/k8s.io/client-go/discovery/discovery_client.go generated vendored Normal file
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/*
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"
"sync"
"time"
"github.com/golang/protobuf/proto"
openapi_v2 "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"
utilruntime "k8s.io/apimachinery/pkg/util/runtime"
"k8s.io/apimachinery/pkg/version"
"k8s.io/client-go/kubernetes/scheme"
restclient "k8s.io/client-go/rest"
)
const (
// defaultRetries is the number of times a resource discovery is repeated if an api group disappears on the fly (e.g. ThirdPartyResources).
defaultRetries = 2
// protobuf mime type
mimePb = "application/com.github.proto-openapi.spec.v2@v1.0+protobuf"
// defaultTimeout is the maximum amount of time per request when no timeout has been set on a RESTClient.
// Defaults to 32s in order to have a distinguishable length of time, relative to other timeouts that exist.
defaultTimeout = 32 * time.Second
)
// 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.
// Note that If the ServerResourcesForGroupVersion method returns a cache miss
// error, the user needs to explicitly call Invalidate to clear the cache,
// otherwise the same cache miss error will be returned next time.
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 that is older than the current time
// is used.
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.
//
// The returned resource list might be non-nil with partial results even in the case of
// non-nil error.
//
// Deprecated: use ServerGroupsAndResources instead.
ServerResources() ([]*metav1.APIResourceList, error)
// ServerResources returns the supported groups and resources for all groups and versions.
//
// The returned group and resource lists might be non-nil with partial results even in the
// case of non-nil error.
ServerGroupsAndResources() ([]*metav1.APIGroup, []*metav1.APIResourceList, error)
// ServerPreferredResources returns the supported resources with the version preferred by the
// server.
//
// The returned group and resource lists might be non-nil with partial results even in the
// case of non-nil error.
ServerPreferredResources() ([]*metav1.APIResourceList, error)
// ServerPreferredNamespacedResources returns the supported namespaced resources with the
// version preferred by the server.
//
// The returned resource list might be non-nil with partial results even in the case of
// non-nil error.
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{}
}
// prepend the group retrieved from /api to the list if not empty
if len(v.Versions) != 0 {
apiGroupList.Groups = append([]metav1.APIGroup{apiGroup}, apiGroupList.Groups...)
}
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.
// Deprecated: use ServerGroupsAndResources instead.
func (d *DiscoveryClient) ServerResources() ([]*metav1.APIResourceList, error) {
_, rs, err := d.ServerGroupsAndResources()
return rs, err
}
// ServerGroupsAndResources returns the supported resources for all groups and versions.
func (d *DiscoveryClient) ServerGroupsAndResources() ([]*metav1.APIGroup, []*metav1.APIResourceList, error) {
return withRetries(defaultRetries, func() ([]*metav1.APIGroup, []*metav1.APIResourceList, error) {
return ServerGroupsAndResources(d)
})
}
// 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
}
// ServerResources uses the provided discovery interface to look up supported resources for all groups and versions.
// Deprecated: use ServerGroupsAndResources instead.
func ServerResources(d DiscoveryInterface) ([]*metav1.APIResourceList, error) {
_, rs, err := ServerGroupsAndResources(d)
return rs, err
}
func ServerGroupsAndResources(d DiscoveryInterface) ([]*metav1.APIGroup, []*metav1.APIResourceList, error) {
sgs, err := d.ServerGroups()
if sgs == nil {
return nil, nil, err
}
resultGroups := []*metav1.APIGroup{}
for i := range sgs.Groups {
resultGroups = append(resultGroups, &sgs.Groups[i])
}
groupVersionResources, failedGroups := fetchGroupVersionResources(d, sgs)
// order results by group/version discovery order
result := []*metav1.APIResourceList{}
for _, apiGroup := range sgs.Groups {
for _, version := range apiGroup.Versions {
gv := schema.GroupVersion{Group: apiGroup.Name, Version: version.Version}
if resources, ok := groupVersionResources[gv]; ok {
result = append(result, resources)
}
}
}
if len(failedGroups) == 0 {
return resultGroups, result, nil
}
return resultGroups, result, &ErrGroupDiscoveryFailed{Groups: failedGroups}
}
// ServerPreferredResources uses the provided discovery interface to look up preferred resources
func ServerPreferredResources(d DiscoveryInterface) ([]*metav1.APIResourceList, error) {
serverGroupList, err := d.ServerGroups()
if err != nil {
return nil, err
}
groupVersionResources, failedGroups := fetchGroupVersionResources(d, serverGroupList)
result := []*metav1.APIResourceList{}
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, ok := groupVersionResources[groupVersion]
if !ok {
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}
}
// fetchServerResourcesForGroupVersions uses the discovery client to fetch the resources for the specified groups in parallel.
func fetchGroupVersionResources(d DiscoveryInterface, apiGroups *metav1.APIGroupList) (map[schema.GroupVersion]*metav1.APIResourceList, map[schema.GroupVersion]error) {
groupVersionResources := make(map[schema.GroupVersion]*metav1.APIResourceList)
failedGroups := make(map[schema.GroupVersion]error)
wg := &sync.WaitGroup{}
resultLock := &sync.Mutex{}
for _, apiGroup := range apiGroups.Groups {
for _, version := range apiGroup.Versions {
groupVersion := schema.GroupVersion{Group: apiGroup.Name, Version: version.Version}
wg.Add(1)
go func() {
defer wg.Done()
defer utilruntime.HandleCrash()
apiResourceList, err := d.ServerResourcesForGroupVersion(groupVersion.String())
// lock to record results
resultLock.Lock()
defer resultLock.Unlock()
if err != nil {
// TODO: maybe restrict this to NotFound errors
failedGroups[groupVersion] = err
}
if apiResourceList != nil {
// even in case of error, some fallback might have been returned
groupVersionResources[groupVersion] = apiResourceList
}
}()
}
}
wg.Wait()
return groupVersionResources, failedGroups
}
// ServerPreferredResources returns the supported resources with the version preferred by the
// server.
func (d *DiscoveryClient) ServerPreferredResources() ([]*metav1.APIResourceList, error) {
_, rs, err := withRetries(defaultRetries, func() ([]*metav1.APIGroup, []*metav1.APIResourceList, error) {
rs, err := ServerPreferredResources(d)
return nil, rs, err
})
return rs, err
}
// ServerPreferredNamespacedResources returns the supported namespaced resources with the
// version preferred by the server.
func (d *DiscoveryClient) ServerPreferredNamespacedResources() ([]*metav1.APIResourceList, error) {
return ServerPreferredNamespacedResources(d)
}
// ServerPreferredNamespacedResources uses the provided discovery interface to look up preferred namespaced resources
func ServerPreferredNamespacedResources(d DiscoveryInterface) ([]*metav1.APIResourceList, error) {
all, err := ServerPreferredResources(d)
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("unable to parse the server version: %v", 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("/openapi/v2").SetHeader("Accept", mimePb).Do().Raw()
if err != nil {
if errors.IsForbidden(err) || errors.IsNotFound(err) || errors.IsNotAcceptable(err) {
// single endpoint not found/registered in old server, try to fetch old endpoint
// TODO: remove this when kubectl/client-go don't work with 1.9 server
data, err = d.restClient.Get().AbsPath("/swagger-2.0.0.pb-v1").Do().Raw()
if err != nil {
return nil, err
}
} else {
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.APIGroup, []*metav1.APIResourceList, error)) ([]*metav1.APIGroup, []*metav1.APIResourceList, error) {
var result []*metav1.APIResourceList
var resultGroups []*metav1.APIGroup
var err error
for i := 0; i < maxRetries; i++ {
resultGroups, result, err = f()
if err == nil {
return resultGroups, result, nil
}
if _, ok := err.(*ErrGroupDiscoveryFailed); !ok {
return nil, nil, err
}
}
return resultGroups, result, err
}
func setDiscoveryDefaults(config *restclient.Config) error {
config.APIPath = ""
config.GroupVersion = nil
if config.Timeout == 0 {
config.Timeout = defaultTimeout
}
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"}
}
// RESTClient returns a RESTClient that is used to communicate
// with API server by this client implementation.
func (d *DiscoveryClient) RESTClient() restclient.Interface {
if d == nil {
return nil
}
return d.restClient
}

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/*
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 discovery provides ways to discover server-supported
// API groups, versions and resources.
package discovery

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/*
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 discovery
import (
"fmt"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/runtime/schema"
"k8s.io/apimachinery/pkg/util/sets"
apimachineryversion "k8s.io/apimachinery/pkg/version"
)
// MatchesServerVersion queries the server to compares the build version
// (git hash) of the client with the server's build version. It returns an error
// if it failed to contact the server or if the versions are not an exact match.
func MatchesServerVersion(clientVersion apimachineryversion.Info, client DiscoveryInterface) error {
sVer, err := client.ServerVersion()
if err != nil {
return fmt.Errorf("couldn't read version from server: %v", err)
}
// GitVersion includes GitCommit and GitTreeState, but best to be safe?
if clientVersion.GitVersion != sVer.GitVersion || clientVersion.GitCommit != sVer.GitCommit || clientVersion.GitTreeState != sVer.GitTreeState {
return fmt.Errorf("server version (%#v) differs from client version (%#v)", sVer, clientVersion)
}
return nil
}
// ServerSupportsVersion returns an error if the server doesn't have the required version
func ServerSupportsVersion(client DiscoveryInterface, requiredGV schema.GroupVersion) error {
groups, err := client.ServerGroups()
if err != nil {
// This is almost always a connection error, and higher level code should treat this as a generic error,
// not a negotiation specific error.
return err
}
versions := metav1.ExtractGroupVersions(groups)
serverVersions := sets.String{}
for _, v := range versions {
serverVersions.Insert(v)
}
if serverVersions.Has(requiredGV.String()) {
return nil
}
// If the server supports no versions, then we should pretend it has the version because of old servers.
// This can happen because discovery fails due to 403 Forbidden errors
if len(serverVersions) == 0 {
return nil
}
return fmt.Errorf("server does not support API version %q", requiredGV)
}
// GroupVersionResources converts APIResourceLists to the GroupVersionResources.
func GroupVersionResources(rls []*metav1.APIResourceList) (map[schema.GroupVersionResource]struct{}, error) {
gvrs := map[schema.GroupVersionResource]struct{}{}
for _, rl := range rls {
gv, err := schema.ParseGroupVersion(rl.GroupVersion)
if err != nil {
return nil, err
}
for i := range rl.APIResources {
gvrs[schema.GroupVersionResource{Group: gv.Group, Version: gv.Version, Resource: rl.APIResources[i].Name}] = struct{}{}
}
}
return gvrs, nil
}
// FilteredBy filters by the given predicate. Empty APIResourceLists are dropped.
func FilteredBy(pred ResourcePredicate, rls []*metav1.APIResourceList) []*metav1.APIResourceList {
result := []*metav1.APIResourceList{}
for _, rl := range rls {
filtered := *rl
filtered.APIResources = nil
for i := range rl.APIResources {
if pred.Match(rl.GroupVersion, &rl.APIResources[i]) {
filtered.APIResources = append(filtered.APIResources, rl.APIResources[i])
}
}
if filtered.APIResources != nil {
result = append(result, &filtered)
}
}
return result
}
// ResourcePredicate has a method to check if a resource matches a given condition.
type ResourcePredicate interface {
Match(groupVersion string, r *metav1.APIResource) bool
}
// ResourcePredicateFunc returns true if it matches a resource based on a custom condition.
type ResourcePredicateFunc func(groupVersion string, r *metav1.APIResource) bool
// Match is a wrapper around ResourcePredicateFunc.
func (fn ResourcePredicateFunc) Match(groupVersion string, r *metav1.APIResource) bool {
return fn(groupVersion, r)
}
// SupportsAllVerbs is a predicate matching a resource iff all given verbs are supported.
type SupportsAllVerbs struct {
Verbs []string
}
// Match checks if a resource contains all the given verbs.
func (p SupportsAllVerbs) Match(groupVersion string, r *metav1.APIResource) bool {
return sets.NewString([]string(r.Verbs)...).HasAll(p.Verbs...)
}