sigs.k8s.io/cluster-api@v1.7.1/internal/contract/references.go (about)

     1  /*
     2  Copyright 2021 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 contract
    18  
    19  import (
    20  	"strings"
    21  
    22  	"github.com/pkg/errors"
    23  	corev1 "k8s.io/api/core/v1"
    24  	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
    25  	"k8s.io/klog/v2"
    26  )
    27  
    28  // Ref provide a helper struct for working with references in Unstructured objects.
    29  type Ref struct {
    30  	path Path
    31  }
    32  
    33  // Path returns the path of the reference.
    34  func (r *Ref) Path() Path {
    35  	return r.path
    36  }
    37  
    38  // Get gets the reference value from the Unstructured object.
    39  func (r *Ref) Get(obj *unstructured.Unstructured) (*corev1.ObjectReference, error) {
    40  	return GetNestedRef(obj, r.path...)
    41  }
    42  
    43  // Set sets the reference value in the Unstructured object.
    44  func (r *Ref) Set(obj, refObj *unstructured.Unstructured) error {
    45  	return SetNestedRef(obj, refObj, r.path...)
    46  }
    47  
    48  // GetNestedRef returns the ref value from a nested field in an Unstructured object.
    49  func GetNestedRef(obj *unstructured.Unstructured, fields ...string) (*corev1.ObjectReference, error) {
    50  	ref := &corev1.ObjectReference{}
    51  	if v, ok, err := unstructured.NestedString(obj.UnstructuredContent(), append(fields, "apiVersion")...); ok && err == nil {
    52  		ref.APIVersion = v
    53  	} else {
    54  		return nil, errors.Errorf("failed to get %s.apiVersion from %s", strings.Join(fields, "."), obj.GetKind())
    55  	}
    56  	if v, ok, err := unstructured.NestedString(obj.UnstructuredContent(), append(fields, "kind")...); ok && err == nil {
    57  		ref.Kind = v
    58  	} else {
    59  		return nil, errors.Errorf("failed to get %s.kind from %s", strings.Join(fields, "."), obj.GetKind())
    60  	}
    61  	if v, ok, err := unstructured.NestedString(obj.UnstructuredContent(), append(fields, "name")...); ok && err == nil {
    62  		ref.Name = v
    63  	} else {
    64  		return nil, errors.Errorf("failed to get %s.name from %s", strings.Join(fields, "."), obj.GetKind())
    65  	}
    66  	if v, ok, err := unstructured.NestedString(obj.UnstructuredContent(), append(fields, "namespace")...); ok && err == nil {
    67  		ref.Namespace = v
    68  	} else {
    69  		return nil, errors.Errorf("failed to get %s.namespace from %s", strings.Join(fields, "."), obj.GetKind())
    70  	}
    71  	return ref, nil
    72  }
    73  
    74  // SetNestedRef sets the value of a nested field in an Unstructured to a reference to the refObj provided.
    75  func SetNestedRef(obj, refObj *unstructured.Unstructured, fields ...string) error {
    76  	ref := map[string]interface{}{
    77  		"kind":       refObj.GetKind(),
    78  		"namespace":  refObj.GetNamespace(),
    79  		"name":       refObj.GetName(),
    80  		"apiVersion": refObj.GetAPIVersion(),
    81  	}
    82  	if err := unstructured.SetNestedField(obj.UnstructuredContent(), ref, fields...); err != nil {
    83  		return errors.Wrapf(err, "failed to set object reference on object %v %s",
    84  			obj.GroupVersionKind(), klog.KObj(obj))
    85  	}
    86  	return nil
    87  }
    88  
    89  // ObjToRef returns a reference to the given object.
    90  // Note: This function only operates on Unstructured instead of client.Object
    91  // because it is only safe to assume for Unstructured that the GVK is set.
    92  func ObjToRef(obj *unstructured.Unstructured) *corev1.ObjectReference {
    93  	gvk := obj.GetObjectKind().GroupVersionKind()
    94  	return &corev1.ObjectReference{
    95  		Kind:       gvk.Kind,
    96  		APIVersion: gvk.GroupVersion().String(),
    97  		Namespace:  obj.GetNamespace(),
    98  		Name:       obj.GetName(),
    99  	}
   100  }