k8s.io/apiserver@v0.31.1/pkg/apis/apiserver/load/load.go (about)

     1  /*
     2  Copyright 2023 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 load
    18  
    19  import (
    20  	"fmt"
    21  	"io"
    22  	"os"
    23  
    24  	"k8s.io/apimachinery/pkg/runtime"
    25  	"k8s.io/apimachinery/pkg/runtime/serializer"
    26  	api "k8s.io/apiserver/pkg/apis/apiserver"
    27  	"k8s.io/apiserver/pkg/apis/apiserver/install"
    28  	externalapi "k8s.io/apiserver/pkg/apis/apiserver/v1alpha1"
    29  )
    30  
    31  var (
    32  	scheme = runtime.NewScheme()
    33  	codecs = serializer.NewCodecFactory(scheme, serializer.EnableStrict)
    34  )
    35  
    36  func init() {
    37  	install.Install(scheme)
    38  }
    39  
    40  func LoadFromFile(file string) (*api.AuthorizationConfiguration, error) {
    41  	data, err := os.ReadFile(file)
    42  	if err != nil {
    43  		return nil, err
    44  	}
    45  	return LoadFromData(data)
    46  }
    47  
    48  func LoadFromReader(reader io.Reader) (*api.AuthorizationConfiguration, error) {
    49  	if reader == nil {
    50  		// no reader specified, use default config
    51  		return LoadFromData(nil)
    52  	}
    53  
    54  	data, err := io.ReadAll(reader)
    55  	if err != nil {
    56  		return nil, err
    57  	}
    58  	return LoadFromData(data)
    59  }
    60  
    61  func LoadFromData(data []byte) (*api.AuthorizationConfiguration, error) {
    62  	if len(data) == 0 {
    63  		// no config provided, return default
    64  		externalConfig := &externalapi.AuthorizationConfiguration{}
    65  		scheme.Default(externalConfig)
    66  		internalConfig := &api.AuthorizationConfiguration{}
    67  		if err := scheme.Convert(externalConfig, internalConfig, nil); err != nil {
    68  			return nil, err
    69  		}
    70  		return internalConfig, nil
    71  	}
    72  
    73  	decodedObj, err := runtime.Decode(codecs.UniversalDecoder(), data)
    74  	if err != nil {
    75  		return nil, err
    76  	}
    77  	configuration, ok := decodedObj.(*api.AuthorizationConfiguration)
    78  	if !ok {
    79  		return nil, fmt.Errorf("expected AuthorizationConfiguration, got %T", decodedObj)
    80  	}
    81  	return configuration, nil
    82  }