k8s.io/apiserver@v0.31.1/pkg/admission/plugin/webhook/config/kubeconfig.go (about)

     1  /*
     2  Copyright 2017 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 config
    18  
    19  import (
    20  	"fmt"
    21  	"io"
    22  	"path"
    23  
    24  	"k8s.io/apimachinery/pkg/runtime"
    25  	"k8s.io/apimachinery/pkg/runtime/serializer"
    26  	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
    27  	"k8s.io/apimachinery/pkg/util/validation/field"
    28  	"k8s.io/apiserver/pkg/admission/plugin/webhook/config/apis/webhookadmission"
    29  	"k8s.io/apiserver/pkg/admission/plugin/webhook/config/apis/webhookadmission/v1"
    30  	"k8s.io/apiserver/pkg/admission/plugin/webhook/config/apis/webhookadmission/v1alpha1"
    31  )
    32  
    33  var (
    34  	scheme = runtime.NewScheme()
    35  	codecs = serializer.NewCodecFactory(scheme)
    36  )
    37  
    38  func init() {
    39  	utilruntime.Must(webhookadmission.AddToScheme(scheme))
    40  	utilruntime.Must(v1.AddToScheme(scheme))
    41  	utilruntime.Must(v1alpha1.AddToScheme(scheme))
    42  }
    43  
    44  // LoadConfig extract the KubeConfigFile from configFile
    45  func LoadConfig(configFile io.Reader) (string, error) {
    46  	var kubeconfigFile string
    47  	if configFile != nil {
    48  		// we have a config so parse it.
    49  		data, err := io.ReadAll(configFile)
    50  		if err != nil {
    51  			return "", err
    52  		}
    53  		decoder := codecs.UniversalDecoder()
    54  		decodedObj, err := runtime.Decode(decoder, data)
    55  		if err != nil {
    56  			return "", err
    57  		}
    58  		config, ok := decodedObj.(*webhookadmission.WebhookAdmission)
    59  		if !ok {
    60  			return "", fmt.Errorf("unexpected type: %T", decodedObj)
    61  		}
    62  
    63  		if !path.IsAbs(config.KubeConfigFile) {
    64  			return "", field.Invalid(field.NewPath("kubeConfigFile"), config.KubeConfigFile, "must be an absolute file path")
    65  		}
    66  
    67  		kubeconfigFile = config.KubeConfigFile
    68  	}
    69  	return kubeconfigFile, nil
    70  }