1/*
2Copyright 2019 The Kubernetes Authors.
3
4Licensed under the Apache License, Version 2.0 (the "License");
5you may not use this file except in compliance with the License.
6You may obtain a copy of the License at
7
8    http://www.apache.org/licenses/LICENSE-2.0
9
10Unless required by applicable law or agreed to in writing, software
11distributed under the License is distributed on an "AS IS" BASIS,
12WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13See the License for the specific language governing permissions and
14limitations under the License.
15*/
16
17package defaulting
18
19import (
20	structuralschema "k8s.io/apiextensions-apiserver/pkg/apiserver/schema"
21	"k8s.io/apimachinery/pkg/runtime"
22)
23
24// isNonNullalbeNull returns true if the item is nil AND it's nullable
25func isNonNullableNull(x interface{}, s *structuralschema.Structural) bool {
26	return x == nil && s != nil && s.Generic.Nullable == false
27}
28
29// Default does defaulting of x depending on default values in s.
30// Default values from s are deep-copied.
31//
32// PruneNonNullableNullsWithoutDefaults has left the non-nullable nulls
33// that have a default here.
34func Default(x interface{}, s *structuralschema.Structural) {
35	if s == nil {
36		return
37	}
38
39	switch x := x.(type) {
40	case map[string]interface{}:
41		for k, prop := range s.Properties {
42			if prop.Default.Object == nil {
43				continue
44			}
45			if _, found := x[k]; !found || isNonNullableNull(x[k], &prop) {
46				x[k] = runtime.DeepCopyJSONValue(prop.Default.Object)
47			}
48		}
49		for k := range x {
50			if prop, found := s.Properties[k]; found {
51				Default(x[k], &prop)
52			} else if s.AdditionalProperties != nil {
53				if isNonNullableNull(x[k], s.AdditionalProperties.Structural) {
54					x[k] = runtime.DeepCopyJSONValue(s.AdditionalProperties.Structural.Default.Object)
55				}
56				Default(x[k], s.AdditionalProperties.Structural)
57			}
58		}
59	case []interface{}:
60		for i := range x {
61			if isNonNullableNull(x[i], s.Items) {
62				x[i] = runtime.DeepCopyJSONValue(s.Items.Default.Object)
63			}
64			Default(x[i], s.Items)
65		}
66	default:
67		// scalars, do nothing
68	}
69}
70