Update to kube v1.17

Signed-off-by: Humble Chirammal <hchiramm@redhat.com>

vendor/k8s.io/apiserver/pkg/util/webhook/client.go

@@ -0,0 +1,224 @@
+/*
+Copyright 2017 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 webhook
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net"
+	"net/url"
+	"strconv"
+
+	"github.com/hashicorp/golang-lru"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	utilerrors "k8s.io/apimachinery/pkg/util/errors"
+	"k8s.io/client-go/rest"
+)
+
+const (
+	defaultCacheSize = 200
+)
+
+// ClientConfig defines parameters required for creating a hook client.
+type ClientConfig struct {
+	Name     string
+	URL      string
+	CABundle []byte
+	Service  *ClientConfigService
+}
+
+// ClientConfigService defines service discovery parameters of the webhook.
+type ClientConfigService struct {
+	Name      string
+	Namespace string
+	Path      string
+	Port      int32
+}
+
+// ClientManager builds REST clients to talk to webhooks. It caches the clients
+// to avoid duplicate creation.
+type ClientManager struct {
+	authInfoResolver     AuthenticationInfoResolver
+	serviceResolver      ServiceResolver
+	negotiatedSerializer runtime.NegotiatedSerializer
+	cache                *lru.Cache
+}
+
+// NewClientManager creates a clientManager.
+func NewClientManager(gvs []schema.GroupVersion, addToSchemaFuncs ...func(s *runtime.Scheme) error) (ClientManager, error) {
+	cache, err := lru.New(defaultCacheSize)
+	if err != nil {
+		return ClientManager{}, err
+	}
+	hookScheme := runtime.NewScheme()
+	for _, addToSchemaFunc := range addToSchemaFuncs {
+		if err := addToSchemaFunc(hookScheme); err != nil {
+			return ClientManager{}, err
+		}
+	}
+	return ClientManager{
+		cache: cache,
+		negotiatedSerializer: serializer.NegotiatedSerializerWrapper(runtime.SerializerInfo{
+			Serializer: serializer.NewCodecFactory(hookScheme).LegacyCodec(gvs...),
+		}),
+	}, nil
+}
+
+// SetAuthenticationInfoResolverWrapper sets the
+// AuthenticationInfoResolverWrapper.
+func (cm *ClientManager) SetAuthenticationInfoResolverWrapper(wrapper AuthenticationInfoResolverWrapper) {
+	if wrapper != nil {
+		cm.authInfoResolver = wrapper(cm.authInfoResolver)
+	}
+}
+
+// SetAuthenticationInfoResolver sets the AuthenticationInfoResolver.
+func (cm *ClientManager) SetAuthenticationInfoResolver(resolver AuthenticationInfoResolver) {
+	cm.authInfoResolver = resolver
+}
+
+// SetServiceResolver sets the ServiceResolver.
+func (cm *ClientManager) SetServiceResolver(sr ServiceResolver) {
+	if sr != nil {
+		cm.serviceResolver = sr
+	}
+}
+
+// Validate checks if ClientManager is properly set up.
+func (cm *ClientManager) Validate() error {
+	var errs []error
+	if cm.negotiatedSerializer == nil {
+		errs = append(errs, fmt.Errorf("the clientManager requires a negotiatedSerializer"))
+	}
+	if cm.serviceResolver == nil {
+		errs = append(errs, fmt.Errorf("the clientManager requires a serviceResolver"))
+	}
+	if cm.authInfoResolver == nil {
+		errs = append(errs, fmt.Errorf("the clientManager requires an authInfoResolver"))
+	}
+	return utilerrors.NewAggregate(errs)
+}
+
+// HookClient get a RESTClient from the cache, or constructs one based on the
+// webhook configuration.
+func (cm *ClientManager) HookClient(cc ClientConfig) (*rest.RESTClient, error) {
+	ccWithNoName := cc
+	ccWithNoName.Name = ""
+	cacheKey, err := json.Marshal(ccWithNoName)
+	if err != nil {
+		return nil, err
+	}
+	if client, ok := cm.cache.Get(string(cacheKey)); ok {
+		return client.(*rest.RESTClient), nil
+	}
+
+	complete := func(cfg *rest.Config) (*rest.RESTClient, error) {
+		// Avoid client-side rate limiting talking to the webhook backend.
+		// Rate limiting should happen when deciding how many requests to serve.
+		cfg.QPS = -1
+
+		// Combine CAData from the config with any existing CA bundle provided
+		if len(cfg.TLSClientConfig.CAData) > 0 {
+			cfg.TLSClientConfig.CAData = append(cfg.TLSClientConfig.CAData, '\n')
+		}
+		cfg.TLSClientConfig.CAData = append(cfg.TLSClientConfig.CAData, cc.CABundle...)
+
+		// Use http/1.1 instead of http/2.
+		// This is a workaround for http/2-enabled clients not load-balancing concurrent requests to multiple backends.
+		// See http://issue.k8s.io/75791 for details.
+		cfg.NextProtos = []string{"http/1.1"}
+
+		cfg.ContentConfig.NegotiatedSerializer = cm.negotiatedSerializer
+		cfg.ContentConfig.ContentType = runtime.ContentTypeJSON
+		client, err := rest.UnversionedRESTClientFor(cfg)
+		if err == nil {
+			cm.cache.Add(string(cacheKey), client)
+		}
+		return client, err
+	}
+
+	if cc.Service != nil {
+		port := cc.Service.Port
+		if port == 0 {
+			// Default to port 443 if no service port is specified
+			port = 443
+		}
+
+		restConfig, err := cm.authInfoResolver.ClientConfigForService(cc.Service.Name, cc.Service.Namespace, int(port))
+		if err != nil {
+			return nil, err
+		}
+		cfg := rest.CopyConfig(restConfig)
+		serverName := cc.Service.Name + "." + cc.Service.Namespace + ".svc"
+
+		host := net.JoinHostPort(serverName, strconv.Itoa(int(port)))
+		cfg.Host = "https://" + host
+		cfg.APIPath = cc.Service.Path
+		// Set the server name if not already set
+		if len(cfg.TLSClientConfig.ServerName) == 0 {
+			cfg.TLSClientConfig.ServerName = serverName
+		}
+
+		delegateDialer := cfg.Dial
+		if delegateDialer == nil {
+			var d net.Dialer
+			delegateDialer = d.DialContext
+		}
+		cfg.Dial = func(ctx context.Context, network, addr string) (net.Conn, error) {
+			if addr == host {
+				u, err := cm.serviceResolver.ResolveEndpoint(cc.Service.Namespace, cc.Service.Name, port)
+				if err != nil {
+					return nil, err
+				}
+				addr = u.Host
+			}
+			return delegateDialer(ctx, network, addr)
+		}
+
+		return complete(cfg)
+	}
+
+	if cc.URL == "" {
+		return nil, &ErrCallingWebhook{WebhookName: cc.Name, Reason: errors.New("webhook configuration must have either service or URL")}
+	}
+
+	u, err := url.Parse(cc.URL)
+	if err != nil {
+		return nil, &ErrCallingWebhook{WebhookName: cc.Name, Reason: fmt.Errorf("Unparsable URL: %v", err)}
+	}
+
+	hostPort := u.Host
+	if len(u.Port()) == 0 {
+		// Default to port 443 if no port is specified
+		hostPort = net.JoinHostPort(hostPort, "443")
+	}
+
+	restConfig, err := cm.authInfoResolver.ClientConfigFor(hostPort)
+	if err != nil {
+		return nil, err
+	}
+
+	cfg := rest.CopyConfig(restConfig)
+	cfg.Host = u.Scheme + "://" + u.Host
+	cfg.APIPath = u.Path
+
+	return complete(cfg)
+}