vendor: revendor metrics-server, custom-metrics-apiserver

vendor/k8s.io/component-base/cli/flag/ciphersuites_flag.go

@@ -25,32 +25,61 @@ import (
 
 // ciphers maps strings into tls package cipher constants in
 // https://golang.org/pkg/crypto/tls/#pkg-constants
+// to be replaced by tls.CipherSuites() when the project migrates to go1.14.
 var ciphers = map[string]uint16{
-	"TLS_RSA_WITH_RC4_128_SHA":                tls.TLS_RSA_WITH_RC4_128_SHA,
 	"TLS_RSA_WITH_3DES_EDE_CBC_SHA":           tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
 	"TLS_RSA_WITH_AES_128_CBC_SHA":            tls.TLS_RSA_WITH_AES_128_CBC_SHA,
 	"TLS_RSA_WITH_AES_256_CBC_SHA":            tls.TLS_RSA_WITH_AES_256_CBC_SHA,
-	"TLS_RSA_WITH_AES_128_CBC_SHA256":         tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
 	"TLS_RSA_WITH_AES_128_GCM_SHA256":         tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
 	"TLS_RSA_WITH_AES_256_GCM_SHA384":         tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
-	"TLS_ECDHE_ECDSA_WITH_RC4_128_SHA":        tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
 	"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
 	"TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
-	"TLS_ECDHE_RSA_WITH_RC4_128_SHA":          tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA,
 	"TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA":     tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
 	"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA":      tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
 	"TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA":      tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
-	"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
-	"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
 	"TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
 	"TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
 	"TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384":   tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
 	"TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384": tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
 	"TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305":    tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
 	"TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305":  tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
+	"TLS_AES_128_GCM_SHA256":                  tls.TLS_AES_128_GCM_SHA256,
+	"TLS_CHACHA20_POLY1305_SHA256":            tls.TLS_CHACHA20_POLY1305_SHA256,
+	"TLS_AES_256_GCM_SHA384":                  tls.TLS_AES_256_GCM_SHA384,
 }
 
-func TLSCipherPossibleValues() []string {
+// to be replaced by tls.InsecureCipherSuites() when the project migrates to go1.14.
+var insecureCiphers = map[string]uint16{
+	"TLS_RSA_WITH_RC4_128_SHA":                tls.TLS_RSA_WITH_RC4_128_SHA,
+	"TLS_RSA_WITH_AES_128_CBC_SHA256":         tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
+	"TLS_ECDHE_ECDSA_WITH_RC4_128_SHA":        tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
+	"TLS_ECDHE_RSA_WITH_RC4_128_SHA":          tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+	"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
+	"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+}
+
+// InsecureTLSCiphers returns the cipher suites implemented by crypto/tls which have
+// security issues.
+func InsecureTLSCiphers() map[string]uint16 {
+	cipherKeys := make(map[string]uint16, len(insecureCiphers))
+	for k, v := range insecureCiphers {
+		cipherKeys[k] = v
+	}
+	return cipherKeys
+}
+
+// InsecureTLSCipherNames returns a list of cipher suite names implemented by crypto/tls
+// which have security issues.
+func InsecureTLSCipherNames() []string {
+	cipherKeys := sets.NewString()
+	for key := range insecureCiphers {
+		cipherKeys.Insert(key)
+	}
+	return cipherKeys.List()
+}
+
+// PreferredTLSCipherNames returns a list of cipher suite names implemented by crypto/tls.
+func PreferredTLSCipherNames() []string {
 	cipherKeys := sets.NewString()
 	for key := range ciphers {
 		cipherKeys.Insert(key)
@@ -58,13 +87,37 @@ func TLSCipherPossibleValues() []string {
 	return cipherKeys.List()
 }
 
+func allCiphers() map[string]uint16 {
+	acceptedCiphers := make(map[string]uint16, len(ciphers)+len(insecureCiphers))
+	for k, v := range ciphers {
+		acceptedCiphers[k] = v
+	}
+	for k, v := range insecureCiphers {
+		acceptedCiphers[k] = v
+	}
+	return acceptedCiphers
+}
+
+// TLSCipherPossibleValues returns all acceptable cipher suite names.
+// This is a combination of both InsecureTLSCipherNames() and PreferredTLSCipherNames().
+func TLSCipherPossibleValues() []string {
+	cipherKeys := sets.NewString()
+	acceptedCiphers := allCiphers()
+	for key := range acceptedCiphers {
+		cipherKeys.Insert(key)
+	}
+	return cipherKeys.List()
+}
+
+// TLSCipherSuites returns a list of cipher suite IDs from the cipher suite names passed.
 func TLSCipherSuites(cipherNames []string) ([]uint16, error) {
 	if len(cipherNames) == 0 {
 		return nil, nil
 	}
 	ciphersIntSlice := make([]uint16, 0)
+	possibleCiphers := allCiphers()
 	for _, cipher := range cipherNames {
-		intValue, ok := ciphers[cipher]
+		intValue, ok := possibleCiphers[cipher]
 		if !ok {
 			return nil, fmt.Errorf("Cipher suite %s not supported or doesn't exist", cipher)
 		}
@@ -80,6 +133,7 @@ var versions = map[string]uint16{
 	"VersionTLS13": tls.VersionTLS13,
 }
 
+// TLSPossibleVersions returns all acceptable values for TLS Version.
 func TLSPossibleVersions() []string {
 	versionsKeys := sets.NewString()
 	for key := range versions {
@@ -88,6 +142,7 @@ func TLSPossibleVersions() []string {
 	return versionsKeys.List()
 }
 
+// TLSVersion returns the TLS Version ID for the version name passed.
 func TLSVersion(versionName string) (uint16, error) {
 	if len(versionName) == 0 {
 		return DefaultTLSVersion(), nil
@@ -98,6 +153,7 @@ func TLSVersion(versionName string) (uint16, error) {
 	return 0, fmt.Errorf("unknown tls version %q", versionName)
 }
 
+// DefaultTLSVersion defines the default TLS Version.
 func DefaultTLSVersion() uint16 {
 	// Can't use SSLv3 because of POODLE and BEAST
 	// Can't use TLSv1.0 because of POODLE and BEAST using CBC cipher

vendor/k8s.io/component-base/cli/flag/ciphersuites_flag_114.go

@@ -0,0 +1,29 @@
+// +build go1.14
+
+/*
+Copyright 2020 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 flag
+
+import (
+	"crypto/tls"
+)
+
+func init() {
+	// support official IANA names as well on go1.14
+	ciphers["TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256"] = tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
+	ciphers["TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256"] = tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
+}

vendor/k8s.io/component-base/cli/flag/flags.go

@@ -21,7 +21,7 @@ import (
 	"strings"
 
 	"github.com/spf13/pflag"
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 // WordSepNormalizeFunc changes all flags that contain "_" separators
@@ -52,3 +52,10 @@ func InitFlags() {
 		klog.V(2).Infof("FLAG: --%s=%q", flag.Name, flag.Value)
 	})
 }
+
+// PrintFlags logs the flags in the flagset
+func PrintFlags(flags *pflag.FlagSet) {
+	flags.VisitAll(func(flag *pflag.Flag) {
+		klog.V(1).Infof("FLAG: --%s=%q", flag.Name, flag.Value)
+	})
+}

vendor/k8s.io/component-base/cli/flag/namedcertkey_flag.go

@@ -75,7 +75,7 @@ type NamedCertKeyArray struct {
 	changed bool
 }
 
-var _ flag.Value = &NamedCertKey{}
+var _ flag.Value = &NamedCertKeyArray{}
 
 // NewNamedKeyCertArray creates a new NamedCertKeyArray with the internal value
 // pointing to p.

vendor/k8s.io/component-base/featuregate/feature_gate.go

@@ -27,7 +27,7 @@ import (
 	"github.com/spf13/pflag"
 
 	"k8s.io/apimachinery/pkg/util/naming"
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 type Feature string

vendor/k8s.io/component-base/logs/OWNERS

@@ -0,0 +1,8 @@
+# See the OWNERS docs at https://go.k8s.io/owners
+
+approvers:
+- sig-instrumentation-approvers
+reviewers:
+- sig-instrumentation-reviewers
+labels:
+- sig/instrumentation

vendor/k8s.io/component-base/logs/json/json.go

@@ -0,0 +1,177 @@
+/*
+Copyright 2020 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 logs
+
+import (
+	"os"
+	"time"
+
+	"github.com/go-logr/logr"
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+)
+
+// Inspired from https://github.com/go-logr/zapr, some functions is copy from the repo.
+
+var (
+	// JSONLogger is global json log format logr
+	JSONLogger logr.Logger
+
+	// timeNow stubbed out for testing
+	timeNow = time.Now
+)
+
+// zapLogger is a logr.Logger that uses Zap to record log.
+type zapLogger struct {
+	// NB: this looks very similar to zap.SugaredLogger, but
+	// deals with our desire to have multiple verbosity levels.
+	l   *zap.Logger
+	lvl int
+}
+
+// implement logr.Logger
+var _ logr.Logger = &zapLogger{}
+
+// Enabled should always return true
+func (l *zapLogger) Enabled() bool {
+	return true
+}
+
+// Info write message to error level log
+func (l *zapLogger) Info(msg string, keysAndVals ...interface{}) {
+	entry := zapcore.Entry{
+		Time:    timeNow(),
+		Message: msg,
+	}
+	checkedEntry := l.l.Core().Check(entry, nil)
+	checkedEntry.Write(l.handleFields(keysAndVals)...)
+}
+
+// dPanic write message to DPanicLevel level log
+// we need implement this because unit test case need stub time.Now
+// otherwise the ts field always changed
+func (l *zapLogger) dPanic(msg string) {
+	entry := zapcore.Entry{
+		Level:   zapcore.DPanicLevel,
+		Time:    timeNow(),
+		Message: msg,
+	}
+	checkedEntry := l.l.Core().Check(entry, nil)
+	checkedEntry.Write(zap.Int("v", l.lvl))
+}
+
+// handleFields converts a bunch of arbitrary key-value pairs into Zap fields.  It takes
+// additional pre-converted Zap fields, for use with automatically attached fields, like
+// `error`.
+func (l *zapLogger) handleFields(args []interface{}, additional ...zap.Field) []zap.Field {
+	// a slightly modified version of zap.SugaredLogger.sweetenFields
+	if len(args) == 0 {
+		// fast-return if we have no suggared fields.
+		return append(additional, zap.Int("v", l.lvl))
+	}
+
+	// unlike Zap, we can be pretty sure users aren't passing structured
+	// fields (since logr has no concept of that), so guess that we need a
+	// little less space.
+	fields := make([]zap.Field, 0, len(args)/2+len(additional)+1)
+	fields = append(fields, zap.Int("v", l.lvl))
+	for i := 0; i < len(args)-1; i += 2 {
+		// check just in case for strongly-typed Zap fields, which is illegal (since
+		// it breaks implementation agnosticism), so we can give a better error message.
+		if _, ok := args[i].(zap.Field); ok {
+			l.dPanic("strongly-typed Zap Field passed to logr")
+			break
+		}
+
+		// process a key-value pair,
+		// ensuring that the key is a string
+		key, val := args[i], args[i+1]
+		keyStr, isString := key.(string)
+		if !isString {
+			// if the key isn't a string, stop logging
+			l.dPanic("non-string key argument passed to logging, ignoring all later arguments")
+			break
+		}
+
+		fields = append(fields, zap.Any(keyStr, val))
+	}
+
+	return append(fields, additional...)
+}
+
+// Error write log message to error level
+func (l *zapLogger) Error(err error, msg string, keysAndVals ...interface{}) {
+	entry := zapcore.Entry{
+		Level:   zapcore.ErrorLevel,
+		Time:    timeNow(),
+		Message: msg,
+	}
+	checkedEntry := l.l.Core().Check(entry, nil)
+	checkedEntry.Write(l.handleFields(keysAndVals, handleError(err))...)
+}
+
+// V return info logr.Logger  with specified level
+func (l *zapLogger) V(level int) logr.Logger {
+	return &zapLogger{
+		lvl: l.lvl + level,
+		l:   l.l,
+	}
+}
+
+// WithValues return logr.Logger with some keys And Values
+func (l *zapLogger) WithValues(keysAndValues ...interface{}) logr.Logger {
+	l.l = l.l.With(l.handleFields(keysAndValues)...)
+	return l
+}
+
+// WithName return logger Named with specified name
+func (l *zapLogger) WithName(name string) logr.Logger {
+	l.l = l.l.Named(name)
+	return l
+}
+
+// encoderConfig config zap encodetime format
+var encoderConfig = zapcore.EncoderConfig{
+	MessageKey: "msg",
+
+	TimeKey:    "ts",
+	EncodeTime: zapcore.EpochMillisTimeEncoder,
+}
+
+// NewJSONLogger creates a new json logr.Logger using the given Zap Logger to log.
+func NewJSONLogger(w zapcore.WriteSyncer) logr.Logger {
+	l, _ := zap.NewProduction()
+	if w == nil {
+		w = os.Stdout
+	}
+	log := l.WithOptions(zap.AddCallerSkip(1),
+		zap.WrapCore(
+			func(zapcore.Core) zapcore.Core {
+				return zapcore.NewCore(zapcore.NewJSONEncoder(encoderConfig), zapcore.AddSync(w), zapcore.DebugLevel)
+			}))
+	return &zapLogger{
+		l: log,
+	}
+}
+
+func handleError(err error) zap.Field {
+	return zap.NamedError("err", err)
+}
+
+func init() {
+	JSONLogger = NewJSONLogger(nil)
+}

vendor/k8s.io/component-base/logs/logs.go

@@ -24,7 +24,7 @@ import (
 
 	"github.com/spf13/pflag"
 	"k8s.io/apimachinery/pkg/util/wait"
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 const logFlushFreqFlagName = "log-flush-frequency"

vendor/k8s.io/component-base/logs/options.go

@@ -0,0 +1,126 @@
+/*
+Copyright 2020 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 logs
+
+import (
+	"flag"
+	"fmt"
+	"strings"
+
+	"github.com/go-logr/logr"
+	"github.com/spf13/pflag"
+
+	"k8s.io/klog/v2"
+)
+
+const (
+	logFormatFlagName = "logging-format"
+	defaultLogFormat  = "text"
+)
+
+// List of logs (k8s.io/klog + k8s.io/component-base/logs) flags supported by all logging formats
+var supportedLogsFlags = map[string]struct{}{
+	"v": {},
+	// TODO: support vmodule after 1.19 Alpha
+}
+
+// Options has klog format parameters
+type Options struct {
+	LogFormat string
+}
+
+// NewOptions return new klog options
+func NewOptions() *Options {
+	return &Options{
+		LogFormat: defaultLogFormat,
+	}
+}
+
+// Validate verifies if any unsupported flag is set
+// for non-default logging format
+func (o *Options) Validate() []error {
+	errs := []error{}
+	if o.LogFormat != defaultLogFormat {
+		allFlags := unsupportedLoggingFlags()
+		for _, fname := range allFlags {
+			if flagIsSet(fname) {
+				errs = append(errs, fmt.Errorf("non-default logging format doesn't honor flag: %s", fname))
+			}
+		}
+	}
+	if _, err := o.Get(); err != nil {
+		errs = append(errs, fmt.Errorf("unsupported log format: %s", o.LogFormat))
+	}
+	return errs
+}
+
+func flagIsSet(name string) bool {
+	f := flag.Lookup(name)
+	if f != nil {
+		return f.DefValue != f.Value.String()
+	}
+	pf := pflag.Lookup(name)
+	if pf != nil {
+		return pf.DefValue != pf.Value.String()
+	}
+	panic("failed to lookup unsupported log flag")
+}
+
+// AddFlags add logging-format flag
+func (o *Options) AddFlags(fs *pflag.FlagSet) {
+	unsupportedFlags := fmt.Sprintf("--%s", strings.Join(unsupportedLoggingFlags(), ", --"))
+	formats := fmt.Sprintf(`"%s"`, strings.Join(logRegistry.List(), `", "`))
+	fs.StringVar(&o.LogFormat, logFormatFlagName, defaultLogFormat, fmt.Sprintf("Sets the log format. Permitted formats: %s.\nNon-default formats don't honor these flags: %s.\nNon-default choices are currently alpha and subject to change without warning.", formats, unsupportedFlags))
+
+	// No new log formats should be added after generation is of flag options
+	logRegistry.Freeze()
+}
+
+// Apply set klog logger from LogFormat type
+func (o *Options) Apply() {
+	// if log format not exists, use nil loggr
+	loggr, _ := o.Get()
+	klog.SetLogger(loggr)
+}
+
+// Get logger with LogFormat field
+func (o *Options) Get() (logr.Logger, error) {
+	return logRegistry.Get(o.LogFormat)
+}
+
+func unsupportedLoggingFlags() []string {
+	allFlags := []string{}
+
+	// k8s.io/klog flags
+	fs := &flag.FlagSet{}
+	klog.InitFlags(fs)
+	fs.VisitAll(func(flag *flag.Flag) {
+		if _, found := supportedLogsFlags[flag.Name]; !found {
+			allFlags = append(allFlags, flag.Name)
+		}
+	})
+
+	// k8s.io/component-base/logs flags
+	pfs := &pflag.FlagSet{}
+	AddFlags(pfs)
+	pfs.VisitAll(func(flag *pflag.Flag) {
+		if _, found := supportedLogsFlags[flag.Name]; !found {
+			allFlags = append(allFlags, flag.Name)
+		}
+	})
+	return allFlags
+}

vendor/k8s.io/component-base/logs/registry.go

@@ -0,0 +1,106 @@
+/*
+Copyright 2020 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 logs
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/go-logr/logr"
+	json "k8s.io/component-base/logs/json"
+)
+
+const (
+	jsonLogFormat = "json"
+)
+
+var logRegistry = NewLogFormatRegistry()
+
+// LogFormatRegistry store klog format registry
+type LogFormatRegistry struct {
+	registry map[string]logr.Logger
+	frozen   bool
+}
+
+// NewLogFormatRegistry return new init LogFormatRegistry struct
+func NewLogFormatRegistry() *LogFormatRegistry {
+	return &LogFormatRegistry{
+		registry: make(map[string]logr.Logger),
+		frozen:   false,
+	}
+}
+
+// Register new log format registry to global logRegistry
+func (lfr *LogFormatRegistry) Register(name string, logger logr.Logger) error {
+	if lfr.frozen {
+		return fmt.Errorf("log format is frozen, unable to register log format")
+	}
+	if _, ok := lfr.registry[name]; ok {
+		return fmt.Errorf("log format: %s already exists", name)
+	}
+	lfr.registry[name] = logger
+	return nil
+}
+
+// Get specified log format logger
+func (lfr *LogFormatRegistry) Get(name string) (logr.Logger, error) {
+	re, ok := lfr.registry[name]
+	if !ok {
+		return nil, fmt.Errorf("log format: %s does not exists", name)
+	}
+	return re, nil
+}
+
+// Set specified log format logger
+func (lfr *LogFormatRegistry) Set(name string, logger logr.Logger) error {
+	if lfr.frozen {
+		return fmt.Errorf("log format is frozen, unable to set log format")
+	}
+
+	lfr.registry[name] = logger
+	return nil
+}
+
+// Delete specified log format logger
+func (lfr *LogFormatRegistry) Delete(name string) error {
+	if lfr.frozen {
+		return fmt.Errorf("log format is frozen, unable to delete log format")
+	}
+
+	delete(lfr.registry, name)
+	return nil
+}
+
+// List names of registered log formats (sorted)
+func (lfr *LogFormatRegistry) List() []string {
+	formats := make([]string, 0, len(lfr.registry))
+	for f := range lfr.registry {
+		formats = append(formats, f)
+	}
+	sort.Strings(formats)
+	return formats
+}
+
+// Freeze freezes the log format registry
+func (lfr *LogFormatRegistry) Freeze() {
+	lfr.frozen = true
+}
+func init() {
+	// Text format is default klog format
+	logRegistry.Register(defaultLogFormat, nil)
+	logRegistry.Register(jsonLogFormat, json.JSONLogger)
+}

vendor/k8s.io/component-base/metrics/counter.go

@@ -45,6 +45,14 @@ func NewCounter(opts *CounterOpts) *Counter {
 	return kc
 }
 
+// Reset resets the underlying prometheus Counter to start counting from 0 again
+func (c *Counter) Reset() {
+	if !c.IsCreated() {
+		return
+	}
+	c.setPrometheusCounter(prometheus.NewCounter(c.CounterOpts.toPromCounterOpts()))
+}
+
 // setPrometheusCounter sets the underlying CounterMetric object, i.e. the thing that does the measurement.
 func (c *Counter) setPrometheusCounter(counter prometheus.Counter) {
 	c.CounterMetric = counter

vendor/k8s.io/component-base/metrics/desc.go

@@ -23,7 +23,7 @@ import (
 	"github.com/blang/semver"
 	"github.com/prometheus/client_golang/prometheus"
 
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 // Desc is a prometheus.Desc extension.

vendor/k8s.io/component-base/metrics/http.go

@@ -17,6 +17,7 @@ limitations under the License.
 package metrics
 
 import (
+	"io"
 	"net/http"
 
 	"github.com/prometheus/client_golang/prometheus/promhttp"
@@ -61,3 +62,16 @@ func (ho *HandlerOpts) toPromhttpHandlerOpts() promhttp.HandlerOpts {
 func HandlerFor(reg Gatherer, opts HandlerOpts) http.Handler {
 	return promhttp.HandlerFor(reg, opts.toPromhttpHandlerOpts())
 }
+
+// HandlerWithReset return an http.Handler with Reset
+func HandlerWithReset(reg KubeRegistry, opts HandlerOpts) http.Handler {
+	defaultHandler := promhttp.HandlerFor(reg, opts.toPromhttpHandlerOpts())
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodDelete {
+			reg.Reset()
+			io.WriteString(w, "metrics reset\n")
+			return
+		}
+		defaultHandler.ServeHTTP(w, r)
+	})
+}

vendor/k8s.io/component-base/metrics/legacyregistry/registry.go

@@ -29,6 +29,18 @@ var (
 	defaultRegistry = metrics.NewKubeRegistry()
 	// DefaultGatherer exposes the global registry gatherer
 	DefaultGatherer metrics.Gatherer = defaultRegistry
+	// Reset calls reset on the global registry
+	Reset = defaultRegistry.Reset
+	// MustRegister registers registerable metrics but uses the global registry.
+	MustRegister = defaultRegistry.MustRegister
+	// RawMustRegister registers prometheus collectors but uses the global registry, this
+	// bypasses the metric stability framework
+	//
+	// Deprecated
+	RawMustRegister = defaultRegistry.RawMustRegister
+
+	// Register registers a collectable metric but uses the global registry
+	Register = defaultRegistry.Register
 )
 
 func init() {
@@ -46,23 +58,12 @@ func Handler() http.Handler {
 	return promhttp.InstrumentMetricHandler(prometheus.DefaultRegisterer, promhttp.HandlerFor(defaultRegistry, promhttp.HandlerOpts{}))
 }
 
-// Register registers a collectable metric but uses the global registry
-func Register(c metrics.Registerable) error {
-	err := defaultRegistry.Register(c)
-	return err
-}
-
-// MustRegister registers registerable metrics but uses the global registry.
-func MustRegister(cs ...metrics.Registerable) {
-	defaultRegistry.MustRegister(cs...)
-}
-
-// RawMustRegister registers prometheus collectors but uses the global registry, this
-// bypasses the metric stability framework
-//
-// Deprecated
-func RawMustRegister(cs ...prometheus.Collector) {
-	defaultRegistry.RawMustRegister(cs...)
+// HandlerWithReset returns an HTTP handler for the DefaultGatherer but invokes
+// registry reset if the http method is DELETE.
+func HandlerWithReset() http.Handler {
+	return promhttp.InstrumentMetricHandler(
+		prometheus.DefaultRegisterer,
+		metrics.HandlerWithReset(defaultRegistry, metrics.HandlerOpts{}))
 }
 
 // CustomRegister registers a custom collector but uses the global registry.

vendor/k8s.io/component-base/metrics/metric.go

@@ -23,7 +23,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	dto "github.com/prometheus/client_model/go"
 
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 /*

vendor/k8s.io/component-base/metrics/options.go

@@ -0,0 +1,79 @@
+/*
+Copyright 2019 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 metrics
+
+import (
+	"fmt"
+
+	"github.com/blang/semver"
+	"github.com/spf13/pflag"
+
+	"k8s.io/component-base/version"
+)
+
+// Options has all parameters needed for exposing metrics from components
+type Options struct {
+	ShowHiddenMetricsForVersion string
+}
+
+// NewOptions returns default metrics options
+func NewOptions() *Options {
+	return &Options{}
+}
+
+// Validate validates metrics flags options.
+func (o *Options) Validate() []error {
+	err := validateShowHiddenMetricsVersion(parseVersion(version.Get()), o.ShowHiddenMetricsForVersion)
+	if err != nil {
+		return []error{err}
+	}
+
+	return nil
+}
+
+// AddFlags adds flags for exposing component metrics.
+func (o *Options) AddFlags(fs *pflag.FlagSet) {
+	if o != nil {
+		o = NewOptions()
+	}
+	fs.StringVar(&o.ShowHiddenMetricsForVersion, "show-hidden-metrics-for-version", o.ShowHiddenMetricsForVersion,
+		"The previous version for which you want to show hidden metrics. "+
+			"Only the previous minor version is meaningful, other values will not be allowed. "+
+			"The format is <major>.<minor>, e.g.: '1.16'. "+
+			"The purpose of this format is make sure you have the opportunity to notice if the next release hides additional metrics, "+
+			"rather than being surprised when they are permanently removed in the release after that.")
+}
+
+// Apply applies parameters into global configuration of metrics.
+func (o *Options) Apply() {
+	if o != nil && len(o.ShowHiddenMetricsForVersion) > 0 {
+		SetShowHidden()
+	}
+}
+
+func validateShowHiddenMetricsVersion(currentVersion semver.Version, targetVersionStr string) error {
+	if targetVersionStr == "" {
+		return nil
+	}
+
+	validVersionStr := fmt.Sprintf("%d.%d", currentVersion.Major, currentVersion.Minor-1)
+	if targetVersionStr != validVersionStr {
+		return fmt.Errorf("--show-hidden-metrics-for-version must be omitted or have the value '%v'. Only the previous minor version is allowed", validVersionStr)
+	}
+
+	return nil
+}

vendor/k8s.io/component-base/metrics/opts.go

@@ -125,7 +125,7 @@ func (o *GaugeOpts) annotateStabilityLevel() {
 
 // convenience function to allow easy transformation to the prometheus
 // counterpart. This will do more once we have a proper label abstraction
-func (o GaugeOpts) toPromGaugeOpts() prometheus.GaugeOpts {
+func (o *GaugeOpts) toPromGaugeOpts() prometheus.GaugeOpts {
 	return prometheus.GaugeOpts{
 		Namespace:   o.Namespace,
 		Subsystem:   o.Subsystem,
@@ -169,7 +169,7 @@ func (o *HistogramOpts) annotateStabilityLevel() {
 
 // convenience function to allow easy transformation to the prometheus
 // counterpart. This will do more once we have a proper label abstraction
-func (o HistogramOpts) toPromHistogramOpts() prometheus.HistogramOpts {
+func (o *HistogramOpts) toPromHistogramOpts() prometheus.HistogramOpts {
 	return prometheus.HistogramOpts{
 		Namespace:   o.Namespace,
 		Subsystem:   o.Subsystem,
@@ -224,7 +224,7 @@ var (
 
 // convenience function to allow easy transformation to the prometheus
 // counterpart. This will do more once we have a proper label abstraction
-func (o SummaryOpts) toPromSummaryOpts() prometheus.SummaryOpts {
+func (o *SummaryOpts) toPromSummaryOpts() prometheus.SummaryOpts {
 	// we need to retain existing quantile behavior for backwards compatibility,
 	// so let's do what prometheus used to do prior to v1.
 	objectives := o.Objectives

vendor/k8s.io/component-base/metrics/processstarttime.go

@@ -22,7 +22,7 @@ import (
 
 	"github.com/prometheus/procfs"
 
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 var processStartTime = NewGaugeVec(

vendor/k8s.io/component-base/metrics/registry.go

@@ -51,19 +51,6 @@ func shouldHide(currentVersion *semver.Version, deprecatedVersion *semver.Versio
 	return false
 }
 
-func validateShowHiddenMetricsVersion(currentVersion semver.Version, targetVersionStr string) error {
-	if targetVersionStr == "" {
-		return nil
-	}
-
-	validVersionStr := fmt.Sprintf("%d.%d", currentVersion.Major, currentVersion.Minor-1)
-	if targetVersionStr != validVersionStr {
-		return fmt.Errorf("--show-hidden-metrics-for-version must be omitted or have the value '%v'. Only the previous minor version is allowed", validVersionStr)
-	}
-
-	return nil
-}
-
 // ValidateShowHiddenMetricsVersion checks invalid version for which show hidden metrics.
 func ValidateShowHiddenMetricsVersion(v string) []error {
 	err := validateShowHiddenMetricsVersion(parseVersion(version.Get()), v)
@@ -110,17 +97,30 @@ type Registerable interface {
 	FQName() string
 }
 
+type resettable interface {
+	Reset()
+}
+
 // KubeRegistry is an interface which implements a subset of prometheus.Registerer and
 // prometheus.Gatherer interfaces
 type KubeRegistry interface {
 	// Deprecated
 	RawMustRegister(...prometheus.Collector)
+	// CustomRegister is our internal variant of Prometheus registry.Register
 	CustomRegister(c StableCollector) error
+	// CustomMustRegister is our internal variant of Prometheus registry.MustRegister
 	CustomMustRegister(cs ...StableCollector)
+	// Register conforms to Prometheus registry.Register
 	Register(Registerable) error
+	// MustRegister conforms to Prometheus registry.MustRegister
 	MustRegister(...Registerable)
+	// Unregister conforms to Prometheus registry.Unregister
 	Unregister(collector Collector) bool
+	// Gather conforms to Prometheus gatherer.Gather
 	Gather() ([]*dto.MetricFamily, error)
+	// Reset invokes the Reset() function on all items in the registry
+	// which are added as resettables.
+	Reset()
 }
 
 // kubeRegistry is a wrapper around a prometheus registry-type object. Upon initialization
@@ -133,6 +133,8 @@ type kubeRegistry struct {
 	stableCollectors     []StableCollector       // stores all stable collector
 	hiddenCollectorsLock sync.RWMutex
 	stableCollectorsLock sync.RWMutex
+	resetLock            sync.RWMutex
+	resettables          []resettable
 }
 
 // Register registers a new Collector to be included in metrics
@@ -142,11 +144,11 @@ type kubeRegistry struct {
 // uniqueness criteria described in the documentation of metric.Desc.
 func (kr *kubeRegistry) Register(c Registerable) error {
 	if c.Create(&kr.version) {
+		defer kr.addResettable(c)
 		return kr.PromRegistry.Register(c)
 	}
 
 	kr.trackHiddenCollector(c)
-
 	return nil
 }
 
@@ -158,6 +160,7 @@ func (kr *kubeRegistry) MustRegister(cs ...Registerable) {
 	for _, c := range cs {
 		if c.Create(&kr.version) {
 			metrics = append(metrics, c)
+			kr.addResettable(c)
 		} else {
 			kr.trackHiddenCollector(c)
 		}
@@ -168,7 +171,7 @@ func (kr *kubeRegistry) MustRegister(cs ...Registerable) {
 // CustomRegister registers a new custom collector.
 func (kr *kubeRegistry) CustomRegister(c StableCollector) error {
 	kr.trackStableCollectors(c)
-
+	defer kr.addResettable(c)
 	if c.Create(&kr.version, c) {
 		return kr.PromRegistry.Register(c)
 	}
@@ -180,14 +183,13 @@ func (kr *kubeRegistry) CustomRegister(c StableCollector) error {
 // error.
 func (kr *kubeRegistry) CustomMustRegister(cs ...StableCollector) {
 	kr.trackStableCollectors(cs...)
-
 	collectors := make([]prometheus.Collector, 0, len(cs))
 	for _, c := range cs {
 		if c.Create(&kr.version, c) {
+			kr.addResettable(c)
 			collectors = append(collectors, c)
 		}
 	}
-
 	kr.PromRegistry.MustRegister(collectors...)
 }
 
@@ -198,6 +200,19 @@ func (kr *kubeRegistry) CustomMustRegister(cs ...StableCollector) {
 // Deprecated
 func (kr *kubeRegistry) RawMustRegister(cs ...prometheus.Collector) {
 	kr.PromRegistry.MustRegister(cs...)
+	for _, c := range cs {
+		kr.addResettable(c)
+	}
+}
+
+// addResettable will automatically add our metric to our reset
+// list if it satisfies the interface
+func (kr *kubeRegistry) addResettable(i interface{}) {
+	kr.resetLock.Lock()
+	defer kr.resetLock.Unlock()
+	if resettable, ok := i.(resettable); ok {
+		kr.resettables = append(kr.resettables, resettable)
+	}
 }
 
 // Unregister unregisters the Collector that equals the Collector passed
@@ -279,6 +294,15 @@ func (kr *kubeRegistry) enableHiddenStableCollectors() {
 	kr.CustomMustRegister(cs...)
 }
 
+// Reset invokes Reset on all metrics that are resettable.
+func (kr *kubeRegistry) Reset() {
+	kr.resetLock.RLock()
+	defer kr.resetLock.RUnlock()
+	for _, r := range kr.resettables {
+		r.Reset()
+	}
+}
+
 // BuildVersion is a helper function that can be easily mocked.
 var BuildVersion = version.Get
 
@@ -287,6 +311,7 @@ func newKubeRegistry(v apimachineryversion.Info) *kubeRegistry {
 		PromRegistry:     prometheus.NewRegistry(),
 		version:          parseVersion(v),
 		hiddenCollectors: make(map[string]Registerable),
+		resettables:      make([]resettable, 0),
 	}
 
 	registriesLock.Lock()
@@ -300,6 +325,5 @@ func newKubeRegistry(v apimachineryversion.Info) *kubeRegistry {
 // pre-registered.
 func NewKubeRegistry() KubeRegistry {
 	r := newKubeRegistry(BuildVersion())
-
 	return r
 }

vendor/k8s.io/component-base/metrics/testutil/metrics.go

@@ -43,8 +43,8 @@ type Metrics map[string]model.Samples
 
 // Equal returns true if all metrics are the same as the arguments.
 func (m *Metrics) Equal(o Metrics) bool {
-	leftKeySet := []string{}
-	rightKeySet := []string{}
+	var leftKeySet []string
+	var rightKeySet []string
 	for k := range *m {
 		leftKeySet = append(leftKeySet, k)
 	}
@@ -92,6 +92,15 @@ func ParseMetrics(data string, output *Metrics) error {
 	}
 }
 
+// TextToMetricFamilies reads 'in' as the simple and flat text-based exchange
+// format and creates MetricFamily proto messages. It returns the MetricFamily
+// proto messages in a map where the metric names are the keys, along with any
+// error encountered.
+func TextToMetricFamilies(in io.Reader) (map[string]*dto.MetricFamily, error) {
+	var textParser expfmt.TextParser
+	return textParser.TextToMetricFamilies(in)
+}
+
 // ExtractMetricSamples parses the prometheus metric samples from the input string.
 func ExtractMetricSamples(metricsBlob string) ([]*model.Sample, error) {
 	dec := expfmt.NewDecoder(strings.NewReader(metricsBlob), expfmt.FmtText)
@@ -114,7 +123,7 @@ func ExtractMetricSamples(metricsBlob string) ([]*model.Sample, error) {
 	}
 }
 
-// PrintSample returns formated representation of metric Sample
+// PrintSample returns formatted representation of metric Sample
 func PrintSample(sample *model.Sample) string {
 	buf := make([]string, 0)
 	// Id is a VERY special label. For 'normal' container it's useless, but it's necessary
@@ -198,22 +207,22 @@ func GetHistogramFromGatherer(gatherer metrics.Gatherer, metricName string) (His
 		return Histogram{}, err
 	}
 	for _, mFamily := range m {
-		if mFamily.Name != nil && *mFamily.Name == metricName {
+		if mFamily.GetName() == metricName {
 			metricFamily = mFamily
 			break
 		}
 	}
 
 	if metricFamily == nil {
-		return Histogram{}, fmt.Errorf("Metric %q not found", metricName)
+		return Histogram{}, fmt.Errorf("metric %q not found", metricName)
 	}
 
 	if metricFamily.GetMetric() == nil {
-		return Histogram{}, fmt.Errorf("Metric %q is empty", metricName)
+		return Histogram{}, fmt.Errorf("metric %q is empty", metricName)
 	}
 
 	if len(metricFamily.GetMetric()) == 0 {
-		return Histogram{}, fmt.Errorf("Metric %q is empty", metricName)
+		return Histogram{}, fmt.Errorf("metric %q is empty", metricName)
 	}
 
 	return Histogram{
@@ -253,6 +262,10 @@ func bucketQuantile(q float64, buckets []bucket) float64 {
 		return buckets[0].upperBound * (rank / buckets[0].count)
 	}
 
+	if b == len(buckets)-1 && math.IsInf(buckets[b].upperBound, 1) {
+		return buckets[len(buckets)-2].upperBound
+	}
+
 	// linear approximation of b-th bucket
 	brank := rank - buckets[b-1].count
 	bSize := buckets[b].upperBound - buckets[b-1].upperBound
@@ -264,24 +277,30 @@ func bucketQuantile(q float64, buckets []bucket) float64 {
 // Quantile computes q-th quantile of a cumulative histogram.
 // It's expected the histogram is valid (by calling Validate)
 func (hist *Histogram) Quantile(q float64) float64 {
-	buckets := []bucket{}
+	var buckets []bucket
 
 	for _, bckt := range hist.Bucket {
 		buckets = append(buckets, bucket{
-			count:      float64(*bckt.CumulativeCount),
-			upperBound: *bckt.UpperBound,
+			count:      float64(bckt.GetCumulativeCount()),
+			upperBound: bckt.GetUpperBound(),
 		})
 	}
 
-	// bucketQuantile expects the upper bound of the last bucket to be +inf
-	// buckets[len(buckets)-1].upperBound = math.Inf(+1)
+	if len(buckets) == 0 || buckets[len(buckets)-1].upperBound != math.Inf(+1) {
+		// The list of buckets in dto.Histogram doesn't include the final +Inf bucket, so we
+		// add it here for the reset of the samples.
+		buckets = append(buckets, bucket{
+			count:      float64(hist.GetSampleCount()),
+			upperBound: math.Inf(+1),
+		})
+	}
 
 	return bucketQuantile(q, buckets)
 }
 
 // Average computes histogram's average value
 func (hist *Histogram) Average() float64 {
-	return *hist.SampleSum / float64(*hist.SampleCount)
+	return hist.GetSampleSum() / float64(hist.GetSampleCount())
 }
 
 // Clear clears all fields of the wrapped histogram
@@ -301,11 +320,11 @@ func (hist *Histogram) Clear() {
 
 // Validate makes sure the wrapped histogram has all necessary fields set and with valid values.
 func (hist *Histogram) Validate() error {
-	if hist.SampleCount == nil || *hist.SampleCount == 0 {
+	if hist.SampleCount == nil || hist.GetSampleCount() == 0 {
 		return fmt.Errorf("nil or empty histogram SampleCount")
 	}
 
-	if hist.SampleSum == nil || *hist.SampleSum == 0 {
+	if hist.SampleSum == nil || hist.GetSampleSum() == 0 {
 		return fmt.Errorf("nil or empty histogram SampleSum")
 	}
 
@@ -313,7 +332,7 @@ func (hist *Histogram) Validate() error {
 		if bckt == nil {
 			return fmt.Errorf("empty histogram bucket")
 		}
-		if bckt.UpperBound == nil || *bckt.UpperBound < 0 {
+		if bckt.UpperBound == nil || bckt.GetUpperBound() < 0 {
 			return fmt.Errorf("nil or negative histogram bucket UpperBound")
 		}
 	}
@@ -325,7 +344,7 @@ func (hist *Histogram) Validate() error {
 func GetGaugeMetricValue(m metrics.GaugeMetric) (float64, error) {
 	metricProto := &dto.Metric{}
 	if err := m.Write(metricProto); err != nil {
-		return 0, fmt.Errorf("Error writing m: %v", err)
+		return 0, fmt.Errorf("error writing m: %v", err)
 	}
 	return metricProto.Gauge.GetValue(), nil
 }
@@ -334,7 +353,7 @@ func GetGaugeMetricValue(m metrics.GaugeMetric) (float64, error) {
 func GetCounterMetricValue(m metrics.CounterMetric) (float64, error) {
 	metricProto := &dto.Metric{}
 	if err := m.(metrics.Metric).Write(metricProto); err != nil {
-		return 0, fmt.Errorf("Error writing m: %v", err)
+		return 0, fmt.Errorf("error writing m: %v", err)
 	}
 	return metricProto.Counter.GetValue(), nil
 }
@@ -343,7 +362,29 @@ func GetCounterMetricValue(m metrics.CounterMetric) (float64, error) {
 func GetHistogramMetricValue(m metrics.ObserverMetric) (float64, error) {
 	metricProto := &dto.Metric{}
 	if err := m.(metrics.Metric).Write(metricProto); err != nil {
-		return 0, fmt.Errorf("Error writing m: %v", err)
+		return 0, fmt.Errorf("error writing m: %v", err)
 	}
 	return metricProto.Histogram.GetSampleSum(), nil
 }
+
+// LabelsMatch returns true if metric has all expected labels otherwise false
+func LabelsMatch(metric *dto.Metric, labelFilter map[string]string) bool {
+	metricLabels := map[string]string{}
+
+	for _, labelPair := range metric.Label {
+		metricLabels[labelPair.GetName()] = labelPair.GetValue()
+	}
+
+	// length comparison then match key to values in the maps
+	if len(labelFilter) > len(metricLabels) {
+		return false
+	}
+
+	for labelName, labelValue := range labelFilter {
+		if value, ok := metricLabels[labelName]; !ok || value != labelValue {
+			return false
+		}
+	}
+
+	return true
+}

vendor/k8s.io/component-base/metrics/testutil/promlint.go

@@ -0,0 +1,161 @@
+/*
+Copyright 2020 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 testutil
+
+import (
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus/testutil/promlint"
+)
+
+// exceptionMetrics is an exception list of metrics which violates promlint rules.
+//
+// The original entries come from the existing metrics when we introduce promlint.
+// We setup this list for allow and not fail on the current violations.
+// Generally speaking, you need to fix the problem for a new metric rather than add it into the list.
+var exceptionMetrics = []string{
+	// k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/server/egressselector
+	"apiserver_egress_dialer_dial_failure_count", // counter metrics should have "_total" suffix
+
+	// k8s.io/apiserver/pkg/util/flowcontrol/fairqueuing/queueset
+	"apiserver_flowcontrol_current_inqueue_requests",   // label names should be written in 'snake_case' not 'camelCase',
+	"apiserver_flowcontrol_current_executing_requests", // label names should be written in 'snake_case' not 'camelCase'
+	"apiserver_flowcontrol_rejected_requests_total",    // label names should be written in 'snake_case' not 'camelCase'
+
+	// k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/server/healthz
+	"apiserver_request_total", // label names should be written in 'snake_case' not 'camelCase'
+
+	// k8s.io/kubernetes/vendor/k8s.io/apiserver/pkg/endpoints/filters
+	"authenticated_user_requests", // counter metrics should have "_total" suffix
+	"authentication_attempts",     // counter metrics should have "_total" suffix
+
+	// kube-apiserver
+	"aggregator_openapi_v2_regeneration_count",
+	"apiserver_admission_step_admission_duration_seconds_summary",
+	"apiserver_current_inflight_requests",
+	"apiserver_longrunning_gauge",
+	"get_token_count",
+	"get_token_fail_count",
+	"ssh_tunnel_open_count",
+	"ssh_tunnel_open_fail_count",
+
+	// kube-controller-manager
+	"attachdetach_controller_forced_detaches",
+	"authenticated_user_requests",
+	"authentication_attempts",
+	"get_token_count",
+	"get_token_fail_count",
+	"node_collector_evictions_number",
+
+	// k8s.io/kubernetes/pkg/kubelet/server/stats
+	// The two metrics have been deprecated and will be removed in release v1.20+.
+	"container_cpu_usage_seconds_total", // non-counter metrics should not have "_total" suffix
+	"node_cpu_usage_seconds_total",      // non-counter metrics should not have "_total" suffix
+}
+
+// A Problem is an issue detected by a Linter.
+type Problem promlint.Problem
+
+func (p *Problem) String() string {
+	return fmt.Sprintf("%s:%s", p.Metric, p.Text)
+}
+
+// A Linter is a Prometheus metrics linter.  It identifies issues with metric
+// names, types, and metadata, and reports them to the caller.
+type Linter struct {
+	promLinter *promlint.Linter
+}
+
+// Lint performs a linting pass, returning a slice of Problems indicating any
+// issues found in the metrics stream.  The slice is sorted by metric name
+// and issue description.
+func (l *Linter) Lint() ([]Problem, error) {
+	promProblems, err := l.promLinter.Lint()
+	if err != nil {
+		return nil, err
+	}
+
+	// Ignore problems those in exception list
+	problems := make([]Problem, 0, len(promProblems))
+	for i := range promProblems {
+		if !l.shouldIgnore(promProblems[i].Metric) {
+			problems = append(problems, Problem(promProblems[i]))
+		}
+	}
+
+	return problems, nil
+}
+
+// shouldIgnore returns true if metric in the exception list, otherwise returns false.
+func (l *Linter) shouldIgnore(metricName string) bool {
+	for i := range exceptionMetrics {
+		if metricName == exceptionMetrics[i] {
+			return true
+		}
+	}
+
+	return false
+}
+
+// NewPromLinter creates a new Linter that reads an input stream of Prometheus metrics.
+// Only the text exposition format is supported.
+func NewPromLinter(r io.Reader) *Linter {
+	return &Linter{
+		promLinter: promlint.New(r),
+	}
+}
+
+func mergeProblems(problems []Problem) string {
+	var problemsMsg []string
+
+	for index := range problems {
+		problemsMsg = append(problemsMsg, problems[index].String())
+	}
+
+	return strings.Join(problemsMsg, ",")
+}
+
+// shouldIgnore returns true if metric in the exception list, otherwise returns false.
+func shouldIgnore(metricName string) bool {
+	for i := range exceptionMetrics {
+		if metricName == exceptionMetrics[i] {
+			return true
+		}
+	}
+
+	return false
+}
+
+// getLintError will ignore the metrics in exception list and converts lint problem to error.
+func getLintError(problems []promlint.Problem) error {
+	var filteredProblems []Problem
+	for _, problem := range problems {
+		if shouldIgnore(problem.Metric) {
+			continue
+		}
+
+		filteredProblems = append(filteredProblems, Problem(problem))
+	}
+
+	if len(filteredProblems) == 0 {
+		return nil
+	}
+
+	return fmt.Errorf("lint error: %s", mergeProblems(filteredProblems))
+}

vendor/k8s.io/component-base/metrics/testutil/testutil.go

@@ -30,6 +30,14 @@ import (
 // pedantic Registry. It then does the same as GatherAndCompare, gathering the
 // metrics from the pedantic Registry.
 func CollectAndCompare(c metrics.Collector, expected io.Reader, metricNames ...string) error {
+	lintProblems, err := testutil.CollectAndLint(c, metricNames...)
+	if err != nil {
+		return err
+	}
+	if err := getLintError(lintProblems); err != nil {
+		return err
+	}
+
 	return testutil.CollectAndCompare(c, expected, metricNames...)
 }
 
@@ -38,6 +46,14 @@ func CollectAndCompare(c metrics.Collector, expected io.Reader, metricNames ...s
 // exposition format. If any metricNames are provided, only metrics with those
 // names are compared.
 func GatherAndCompare(g metrics.Gatherer, expected io.Reader, metricNames ...string) error {
+	lintProblems, err := testutil.GatherAndLint(g, metricNames...)
+	if err != nil {
+		return err
+	}
+	if err := getLintError(lintProblems); err != nil {
+		return err
+	}
+
 	return testutil.GatherAndCompare(g, expected, metricNames...)
 }
 

vendor/k8s.io/component-base/metrics/version.go

@@ -25,7 +25,7 @@ var (
 			Help:           "A metric with a constant '1' value labeled by major, minor, git version, git commit, git tree state, build date, Go version, and compiler from which Kubernetes was built, and platform on which it is running.",
 			StabilityLevel: ALPHA,
 		},
-		[]string{"major", "minor", "gitVersion", "gitCommit", "gitTreeState", "buildDate", "goVersion", "compiler", "platform"},
+		[]string{"major", "minor", "git_version", "git_commit", "git_tree_state", "build_date", "go_version", "compiler", "platform"},
 	)
 )