k8s.io/kubernetes@v1.31.0-alpha.0.0.20240520171757-56147500dadc/pkg/features/client_adapter.go (about)

     1  /*
     2  Copyright 2024 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package features
    18  
    19  import (
    20  	"fmt"
    21  
    22  	clientfeatures "k8s.io/client-go/features"
    23  	"k8s.io/component-base/featuregate"
    24  )
    25  
    26  // clientAdapter adapts a k8s.io/component-base/featuregate.MutableFeatureGate to client-go's
    27  // feature Gate and Registry interfaces. The component-base types Feature, FeatureSpec, and
    28  // prerelease, and the component-base prerelease constants, are duplicated by parallel types and
    29  // constants in client-go. The parallel types exist to allow the feature gate mechanism to be used
    30  // for client-go features without introducing a circular dependency between component-base and
    31  // client-go.
    32  type clientAdapter struct {
    33  	mfg featuregate.MutableFeatureGate
    34  }
    35  
    36  var _ clientfeatures.Gates = &clientAdapter{}
    37  
    38  func (a *clientAdapter) Enabled(name clientfeatures.Feature) bool {
    39  	return a.mfg.Enabled(featuregate.Feature(name))
    40  }
    41  
    42  var _ clientfeatures.Registry = &clientAdapter{}
    43  
    44  func (a *clientAdapter) Add(in map[clientfeatures.Feature]clientfeatures.FeatureSpec) error {
    45  	out := map[featuregate.Feature]featuregate.FeatureSpec{}
    46  	for name, spec := range in {
    47  		converted := featuregate.FeatureSpec{
    48  			Default:       spec.Default,
    49  			LockToDefault: spec.LockToDefault,
    50  		}
    51  		switch spec.PreRelease {
    52  		case clientfeatures.Alpha:
    53  			converted.PreRelease = featuregate.Alpha
    54  		case clientfeatures.Beta:
    55  			converted.PreRelease = featuregate.Beta
    56  		case clientfeatures.GA:
    57  			converted.PreRelease = featuregate.GA
    58  		case clientfeatures.Deprecated:
    59  			converted.PreRelease = featuregate.Deprecated
    60  		default:
    61  			// The default case implies programmer error.  The same set of prerelease
    62  			// constants must exist in both component-base and client-go, and each one
    63  			// must have a case here.
    64  			panic(fmt.Sprintf("unrecognized prerelease %q of feature %q", spec.PreRelease, name))
    65  		}
    66  		out[featuregate.Feature(name)] = converted
    67  	}
    68  	return a.mfg.Add(out)
    69  }