summaryrefslogtreecommitdiff
path: root/vendor/k8s.io/apimachinery/pkg/util/strategicpatch/meta.go
blob: c31de15e7aa33294d6c14bf5e7b221c375fcf5ea (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
/*
Copyright 2017 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 strategicpatch

import (
	"errors"
	"fmt"
	"reflect"

	"k8s.io/apimachinery/pkg/util/mergepatch"
	forkedjson "k8s.io/apimachinery/third_party/forked/golang/json"
	openapi "k8s.io/kube-openapi/pkg/util/proto"
)

type PatchMeta struct {
	patchStrategies []string
	patchMergeKey   string
}

func (pm PatchMeta) GetPatchStrategies() []string {
	if pm.patchStrategies == nil {
		return []string{}
	}
	return pm.patchStrategies
}

func (pm PatchMeta) SetPatchStrategies(ps []string) {
	pm.patchStrategies = ps
}

func (pm PatchMeta) GetPatchMergeKey() string {
	return pm.patchMergeKey
}

func (pm PatchMeta) SetPatchMergeKey(pmk string) {
	pm.patchMergeKey = pmk
}

type LookupPatchMeta interface {
	// LookupPatchMetadataForStruct gets subschema and the patch metadata (e.g. patch strategy and merge key) for map.
	LookupPatchMetadataForStruct(key string) (LookupPatchMeta, PatchMeta, error)
	// LookupPatchMetadataForSlice get subschema and the patch metadata for slice.
	LookupPatchMetadataForSlice(key string) (LookupPatchMeta, PatchMeta, error)
	// Get the type name of the field
	Name() string
}

type PatchMetaFromStruct struct {
	T reflect.Type
}

func NewPatchMetaFromStruct(dataStruct interface{}) (PatchMetaFromStruct, error) {
	t, err := getTagStructType(dataStruct)
	return PatchMetaFromStruct{T: t}, err
}

var _ LookupPatchMeta = PatchMetaFromStruct{}

func (s PatchMetaFromStruct) LookupPatchMetadataForStruct(key string) (LookupPatchMeta, PatchMeta, error) {
	fieldType, fieldPatchStrategies, fieldPatchMergeKey, err := forkedjson.LookupPatchMetadataForStruct(s.T, key)
	if err != nil {
		return nil, PatchMeta{}, err
	}

	return PatchMetaFromStruct{T: fieldType},
		PatchMeta{
			patchStrategies: fieldPatchStrategies,
			patchMergeKey:   fieldPatchMergeKey,
		}, nil
}

func (s PatchMetaFromStruct) LookupPatchMetadataForSlice(key string) (LookupPatchMeta, PatchMeta, error) {
	subschema, patchMeta, err := s.LookupPatchMetadataForStruct(key)
	if err != nil {
		return nil, PatchMeta{}, err
	}
	elemPatchMetaFromStruct := subschema.(PatchMetaFromStruct)
	t := elemPatchMetaFromStruct.T

	var elemType reflect.Type
	switch t.Kind() {
	// If t is an array or a slice, get the element type.
	// If element is still an array or a slice, return an error.
	// Otherwise, return element type.
	case reflect.Array, reflect.Slice:
		elemType = t.Elem()
		if elemType.Kind() == reflect.Array || elemType.Kind() == reflect.Slice {
			return nil, PatchMeta{}, errors.New("unexpected slice of slice")
		}
	// If t is an pointer, get the underlying element.
	// If the underlying element is neither an array nor a slice, the pointer is pointing to a slice,
	// e.g. https://github.com/kubernetes/kubernetes/blob/bc22e206c79282487ea0bf5696d5ccec7e839a76/staging/src/k8s.io/apimachinery/pkg/util/strategicpatch/patch_test.go#L2782-L2822
	// If the underlying element is either an array or a slice, return its element type.
	case reflect.Ptr:
		t = t.Elem()
		if t.Kind() == reflect.Array || t.Kind() == reflect.Slice {
			t = t.Elem()
		}
		elemType = t
	default:
		return nil, PatchMeta{}, fmt.Errorf("expected slice or array type, but got: %s", s.T.Kind().String())
	}

	return PatchMetaFromStruct{T: elemType}, patchMeta, nil
}

func (s PatchMetaFromStruct) Name() string {
	return s.T.Kind().String()
}

func getTagStructType(dataStruct interface{}) (reflect.Type, error) {
	if dataStruct == nil {
		return nil, mergepatch.ErrBadArgKind(struct{}{}, nil)
	}

	t := reflect.TypeOf(dataStruct)
	// Get the underlying type for pointers
	if t.Kind() == reflect.Ptr {
		t = t.Elem()
	}

	if t.Kind() != reflect.Struct {
		return nil, mergepatch.ErrBadArgKind(struct{}{}, dataStruct)
	}

	return t, nil
}

func GetTagStructTypeOrDie(dataStruct interface{}) reflect.Type {
	t, err := getTagStructType(dataStruct)
	if err != nil {
		panic(err)
	}
	return t
}

type PatchMetaFromOpenAPI struct {
	Schema openapi.Schema
}

func NewPatchMetaFromOpenAPI(s openapi.Schema) PatchMetaFromOpenAPI {
	return PatchMetaFromOpenAPI{Schema: s}
}

var _ LookupPatchMeta = PatchMetaFromOpenAPI{}

func (s PatchMetaFromOpenAPI) LookupPatchMetadataForStruct(key string) (LookupPatchMeta, PatchMeta, error) {
	if s.Schema == nil {
		return nil, PatchMeta{}, nil
	}
	kindItem := NewKindItem(key, s.Schema.GetPath())
	s.Schema.Accept(kindItem)

	err := kindItem.Error()
	if err != nil {
		return nil, PatchMeta{}, err
	}
	return PatchMetaFromOpenAPI{Schema: kindItem.subschema},
		kindItem.patchmeta, nil
}

func (s PatchMetaFromOpenAPI) LookupPatchMetadataForSlice(key string) (LookupPatchMeta, PatchMeta, error) {
	if s.Schema == nil {
		return nil, PatchMeta{}, nil
	}
	sliceItem := NewSliceItem(key, s.Schema.GetPath())
	s.Schema.Accept(sliceItem)

	err := sliceItem.Error()
	if err != nil {
		return nil, PatchMeta{}, err
	}
	return PatchMetaFromOpenAPI{Schema: sliceItem.subschema},
		sliceItem.patchmeta, nil
}

func (s PatchMetaFromOpenAPI) Name() string {
	schema := s.Schema
	return schema.GetName()
}