rebase: update kubernetes to 1.30

updating kubernetes to 1.30 release

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/k8s.io/client-go/features/envvar.go

@@ -0,0 +1,138 @@
+/*
+Copyright 2024 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 features
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"sync"
+	"sync/atomic"
+
+	"k8s.io/apimachinery/pkg/util/naming"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/klog/v2"
+)
+
+// internalPackages are packages that ignored when creating a name for featureGates. These packages are in the common
+// call chains, so they'd be unhelpful as names.
+var internalPackages = []string{"k8s.io/client-go/features/envvar.go"}
+
+var _ Gates = &envVarFeatureGates{}
+
+// newEnvVarFeatureGates creates a feature gate that allows for registration
+// of features and checking if the features are enabled.
+//
+// On the first call to Enabled, the effective state of all known features is loaded from
+// environment variables. The environment variable read for a given feature is formed by
+// concatenating the prefix "KUBE_FEATURE_" with the feature's name.
+//
+// For example, if you have a feature named "MyFeature"
+// setting an environmental variable "KUBE_FEATURE_MyFeature"
+// will allow you to configure the state of that feature.
+//
+// Please note that environmental variables can only be set to the boolean value.
+// Incorrect values will be ignored and logged.
+func newEnvVarFeatureGates(features map[Feature]FeatureSpec) *envVarFeatureGates {
+	known := map[Feature]FeatureSpec{}
+	for name, spec := range features {
+		known[name] = spec
+	}
+
+	fg := &envVarFeatureGates{
+		callSiteName: naming.GetNameFromCallsite(internalPackages...),
+		known:        known,
+	}
+	fg.enabled.Store(map[Feature]bool{})
+
+	return fg
+}
+
+// envVarFeatureGates implements Gates and allows for feature registration.
+type envVarFeatureGates struct {
+	// callSiteName holds the name of the file
+	// that created this instance
+	callSiteName string
+
+	// readEnvVarsOnce guards reading environmental variables
+	readEnvVarsOnce sync.Once
+
+	// known holds known feature gates
+	known map[Feature]FeatureSpec
+
+	// enabled holds a map[Feature]bool
+	// with values explicitly set via env var
+	enabled atomic.Value
+
+	// readEnvVars holds the boolean value which
+	// indicates whether readEnvVarsOnce has been called.
+	readEnvVars atomic.Bool
+}
+
+// Enabled returns true if the key is enabled.  If the key is not known, this call will panic.
+func (f *envVarFeatureGates) Enabled(key Feature) bool {
+	if v, ok := f.getEnabledMapFromEnvVar()[key]; ok {
+		return v
+	}
+	if v, ok := f.known[key]; ok {
+		return v.Default
+	}
+	panic(fmt.Errorf("feature %q is not registered in FeatureGates %q", key, f.callSiteName))
+}
+
+// getEnabledMapFromEnvVar will fill the enabled map on the first call.
+// This is the only time a known feature can be set to a value
+// read from the corresponding environmental variable.
+func (f *envVarFeatureGates) getEnabledMapFromEnvVar() map[Feature]bool {
+	f.readEnvVarsOnce.Do(func() {
+		featureGatesState := map[Feature]bool{}
+		for feature, featureSpec := range f.known {
+			featureState, featureStateSet := os.LookupEnv(fmt.Sprintf("KUBE_FEATURE_%s", feature))
+			if !featureStateSet {
+				continue
+			}
+			boolVal, boolErr := strconv.ParseBool(featureState)
+			switch {
+			case boolErr != nil:
+				utilruntime.HandleError(fmt.Errorf("cannot set feature gate %q to %q, due to %v", feature, featureState, boolErr))
+			case featureSpec.LockToDefault:
+				if boolVal != featureSpec.Default {
+					utilruntime.HandleError(fmt.Errorf("cannot set feature gate %q to %q, feature is locked to %v", feature, featureState, featureSpec.Default))
+					break
+				}
+				featureGatesState[feature] = featureSpec.Default
+			default:
+				featureGatesState[feature] = boolVal
+			}
+		}
+		f.enabled.Store(featureGatesState)
+		f.readEnvVars.Store(true)
+
+		for feature, featureSpec := range f.known {
+			if featureState, ok := featureGatesState[feature]; ok {
+				klog.V(1).InfoS("Feature gate updated state", "feature", feature, "enabled", featureState)
+				continue
+			}
+			klog.V(1).InfoS("Feature gate default state", "feature", feature, "enabled", featureSpec.Default)
+		}
+	})
+	return f.enabled.Load().(map[Feature]bool)
+}
+
+func (f *envVarFeatureGates) hasAlreadyReadEnvVar() bool {
+	return f.readEnvVars.Load()
+}

vendor/k8s.io/client-go/features/features.go

@@ -0,0 +1,143 @@
+/*
+Copyright 2024 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 features
+
+import (
+	"errors"
+
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"sync/atomic"
+)
+
+// NOTE: types Feature, FeatureSpec, prerelease (and its values)
+// were duplicated from the component-base repository
+//
+// for more information please refer to https://docs.google.com/document/d/1g9BGCRw-7ucUxO6OtCWbb3lfzUGA_uU9178wLdXAIfs
+
+const (
+	// Values for PreRelease.
+	Alpha = prerelease("ALPHA")
+	Beta  = prerelease("BETA")
+	GA    = prerelease("")
+
+	// Deprecated
+	Deprecated = prerelease("DEPRECATED")
+)
+
+type prerelease string
+
+type Feature string
+
+type FeatureSpec struct {
+	// Default is the default enablement state for the feature
+	Default bool
+	// LockToDefault indicates that the feature is locked to its default and cannot be changed
+	LockToDefault bool
+	// PreRelease indicates the maturity level of the feature
+	PreRelease prerelease
+}
+
+// Gates indicates whether a given feature is enabled or not.
+type Gates interface {
+	// Enabled returns true if the key is enabled.
+	Enabled(key Feature) bool
+}
+
+// Registry represents an external feature gates registry.
+type Registry interface {
+	// Add adds existing feature gates to the provided registry.
+	//
+	// As of today, this method is used by AddFeaturesToExistingFeatureGates and
+	// ReplaceFeatureGates to take control of the features exposed by this library.
+	Add(map[Feature]FeatureSpec) error
+}
+
+// FeatureGates returns the feature gates exposed by this library.
+//
+// By default, only the default features gates will be returned.
+// The default implementation allows controlling the features
+// via environmental variables.
+// For example, if you have a feature named "MyFeature"
+// setting an environmental variable "KUBE_FEATURE_MyFeature"
+// will allow you to configure the state of that feature.
+//
+// Please note that the actual set of the feature gates
+// might be overwritten by calling ReplaceFeatureGates method.
+func FeatureGates() Gates {
+	return featureGates.Load().(*featureGatesWrapper).Gates
+}
+
+// AddFeaturesToExistingFeatureGates adds the default feature gates to the provided registry.
+// Usually this function is combined with ReplaceFeatureGates to take control of the
+// features exposed by this library.
+func AddFeaturesToExistingFeatureGates(registry Registry) error {
+	return registry.Add(defaultKubernetesFeatureGates)
+}
+
+// ReplaceFeatureGates overwrites the default implementation of the feature gates
+// used by this library.
+//
+// Useful for binaries that would like to have full control of the features
+// exposed by this library, such as allowing consumers of a binary
+// to interact with the features via a command line flag.
+//
+// For example:
+//
+//	// first, register client-go's features to your registry.
+//	clientgofeaturegate.AddFeaturesToExistingFeatureGates(utilfeature.DefaultMutableFeatureGate)
+//	// then replace client-go's feature gates implementation with your implementation
+//	clientgofeaturegate.ReplaceFeatureGates(utilfeature.DefaultMutableFeatureGate)
+func ReplaceFeatureGates(newFeatureGates Gates) {
+	if replaceFeatureGatesWithWarningIndicator(newFeatureGates) {
+		utilruntime.HandleError(errors.New("the default feature gates implementation has already been used and now it's being overwritten. This might lead to unexpected behaviour. Check your initialization order"))
+	}
+}
+
+func replaceFeatureGatesWithWarningIndicator(newFeatureGates Gates) bool {
+	shouldProduceWarning := false
+
+	if defaultFeatureGates, ok := FeatureGates().(*envVarFeatureGates); ok {
+		if defaultFeatureGates.hasAlreadyReadEnvVar() {
+			shouldProduceWarning = true
+		}
+	}
+	wrappedFeatureGates := &featureGatesWrapper{newFeatureGates}
+	featureGates.Store(wrappedFeatureGates)
+
+	return shouldProduceWarning
+}
+
+func init() {
+	envVarGates := newEnvVarFeatureGates(defaultKubernetesFeatureGates)
+
+	wrappedFeatureGates := &featureGatesWrapper{envVarGates}
+	featureGates.Store(wrappedFeatureGates)
+}
+
+// featureGatesWrapper a thin wrapper to satisfy featureGates variable (atomic.Value).
+// That is, all calls to Store for a given Value must use values of the same concrete type.
+type featureGatesWrapper struct {
+	Gates
+}
+
+var (
+	// featureGates is a shared global FeatureGates.
+	//
+	// Top-level commands/options setup that needs to modify this feature gates
+	// should use AddFeaturesToExistingFeatureGates followed by ReplaceFeatureGates.
+	featureGates = &atomic.Value{}
+)

vendor/k8s.io/client-go/features/known_features.go

@@ -0,0 +1,54 @@
+/*
+Copyright 2024 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 features
+
+const (
+	// Every feature gate should add method here following this template:
+	//
+	// // owner: @username
+	// // alpha: v1.4
+	// MyFeature featuregate.Feature = "MyFeature"
+	//
+	// Feature gates should be listed in alphabetical, case-sensitive
+	// (upper before any lower case character) order. This reduces the risk
+	// of code conflicts because changes are more likely to be scattered
+	// across the file.
+
+	// owner: @p0lyn0mial
+	// beta: v1.30
+	//
+	// Allow the client to get a stream of individual items instead of chunking from the server.
+	//
+	// NOTE:
+	//  The feature is disabled in Beta by default because
+	//  it will only be turned on for selected control plane component(s).
+	WatchListClient Feature = "WatchListClient"
+
+	// owner: @nilekhc
+	// alpha: v1.30
+	InformerResourceVersion Feature = "InformerResourceVersion"
+)
+
+// defaultKubernetesFeatureGates consists of all known Kubernetes-specific feature keys.
+//
+// To add a new feature, define a key for it above and add it here.
+// After registering with the binary, the features are, by default, controllable using environment variables.
+// For more details, please see envVarFeatureGates implementation.
+var defaultKubernetesFeatureGates = map[Feature]FeatureSpec{
+	WatchListClient:         {Default: false, PreRelease: Beta},
+	InformerResourceVersion: {Default: false, PreRelease: Alpha},
+}