1. update clientset, deepcopy using code-generator

2. add a dummy file tools.go to force "go mod vendor" to see
code-generator as dependencies
3. add a script to update CRD
4. add a README to document CRD updating steps
run go mod tidy
update README

vendor/k8s.io/client-go/rest/config.go

@@ -211,6 +211,12 @@ type TLSClientConfig struct {
 	// CAData holds PEM-encoded bytes (typically read from a root certificates bundle).
 	// CAData takes precedence over CAFile
 	CAData []byte
+
+	// NextProtos is a list of supported application level protocols, in order of preference.
+	// Used to populate tls.Config.NextProtos.
+	// To indicate to the server http/1.1 is preferred over http/2, set to ["http/1.1", "h2"] (though the server is free to ignore that preference).
+	// To use only http/1.1, set to ["http/1.1"].
+	NextProtos []string
 }
 
 var _ fmt.Stringer = TLSClientConfig{}
@@ -236,6 +242,7 @@ func (c TLSClientConfig) String() string {
 		CertData:   c.CertData,
 		KeyData:    c.KeyData,
 		CAData:     c.CAData,
+		NextProtos: c.NextProtos,
 	}
 	// Explicitly mark non-empty credential fields as redacted.
 	if len(cc.CertData) != 0 {
@@ -262,6 +269,9 @@ type ContentConfig struct {
 	GroupVersion *schema.GroupVersion
 	// NegotiatedSerializer is used for obtaining encoders and decoders for multiple
 	// supported media types.
+	//
+	// TODO: NegotiatedSerializer will be phased out as internal clients are removed
+	//   from Kubernetes.
 	NegotiatedSerializer runtime.NegotiatedSerializer
 }
 
@@ -276,14 +286,6 @@ func RESTClientFor(config *Config) (*RESTClient, error) {
 	if config.NegotiatedSerializer == nil {
 		return nil, fmt.Errorf("NegotiatedSerializer is required when initializing a RESTClient")
 	}
-	qps := config.QPS
-	if config.QPS == 0.0 {
-		qps = DefaultQPS
-	}
-	burst := config.Burst
-	if config.Burst == 0 {
-		burst = DefaultBurst
-	}
 
 	baseURL, versionedAPIPath, err := defaultServerUrlFor(config)
 	if err != nil {
@@ -303,7 +305,33 @@ func RESTClientFor(config *Config) (*RESTClient, error) {
 		}
 	}
 
-	return NewRESTClient(baseURL, versionedAPIPath, config.ContentConfig, qps, burst, config.RateLimiter, httpClient)
+	rateLimiter := config.RateLimiter
+	if rateLimiter == nil {
+		qps := config.QPS
+		if config.QPS == 0.0 {
+			qps = DefaultQPS
+		}
+		burst := config.Burst
+		if config.Burst == 0 {
+			burst = DefaultBurst
+		}
+		if qps > 0 {
+			rateLimiter = flowcontrol.NewTokenBucketRateLimiter(qps, burst)
+		}
+	}
+
+	var gv schema.GroupVersion
+	if config.GroupVersion != nil {
+		gv = *config.GroupVersion
+	}
+	clientContent := ClientContentConfig{
+		AcceptContentTypes: config.AcceptContentTypes,
+		ContentType:        config.ContentType,
+		GroupVersion:       gv,
+		Negotiator:         runtime.NewClientNegotiator(config.NegotiatedSerializer, gv),
+	}
+
+	return NewRESTClient(baseURL, versionedAPIPath, clientContent, rateLimiter, httpClient)
 }
 
 // UnversionedRESTClientFor is the same as RESTClientFor, except that it allows
@@ -331,13 +359,33 @@ func UnversionedRESTClientFor(config *Config) (*RESTClient, error) {
 		}
 	}
 
-	versionConfig := config.ContentConfig
-	if versionConfig.GroupVersion == nil {
-		v := metav1.SchemeGroupVersion
-		versionConfig.GroupVersion = &v
+	rateLimiter := config.RateLimiter
+	if rateLimiter == nil {
+		qps := config.QPS
+		if config.QPS == 0.0 {
+			qps = DefaultQPS
+		}
+		burst := config.Burst
+		if config.Burst == 0 {
+			burst = DefaultBurst
+		}
+		if qps > 0 {
+			rateLimiter = flowcontrol.NewTokenBucketRateLimiter(qps, burst)
+		}
 	}
 
-	return NewRESTClient(baseURL, versionedAPIPath, versionConfig, config.QPS, config.Burst, config.RateLimiter, httpClient)
+	gv := metav1.SchemeGroupVersion
+	if config.GroupVersion != nil {
+		gv = *config.GroupVersion
+	}
+	clientContent := ClientContentConfig{
+		AcceptContentTypes: config.AcceptContentTypes,
+		ContentType:        config.ContentType,
+		GroupVersion:       gv,
+		Negotiator:         runtime.NewClientNegotiator(config.NegotiatedSerializer, gv),
+	}
+
+	return NewRESTClient(baseURL, versionedAPIPath, clientContent, rateLimiter, httpClient)
 }
 
 // SetKubernetesDefaults sets default values on the provided client config for accessing the
@@ -503,6 +551,7 @@ func AnonymousClientConfig(config *Config) *Config {
 			ServerName: config.ServerName,
 			CAFile:     config.TLSClientConfig.CAFile,
 			CAData:     config.TLSClientConfig.CAData,
+			NextProtos: config.TLSClientConfig.NextProtos,
 		},
 		RateLimiter:        config.RateLimiter,
 		UserAgent:          config.UserAgent,
@@ -541,6 +590,7 @@ func CopyConfig(config *Config) *Config {
 			CertData:   config.TLSClientConfig.CertData,
 			KeyData:    config.TLSClientConfig.KeyData,
 			CAData:     config.TLSClientConfig.CAData,
+			NextProtos: config.TLSClientConfig.NextProtos,
 		},
 		UserAgent:          config.UserAgent,
 		DisableCompression: config.DisableCompression,