1/*
2Copyright 2020 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 structuralschema "k8s.io/apiextensions-apiserver/pkg/apiserver/schema"
20
21func isNonNullableNonDefaultableNull(x interface{}, s *structuralschema.Structural) bool {
22	return x == nil && s != nil && s.Generic.Nullable == false && s.Default.Object == nil
23}
24
25func getSchemaForField(field string, s *structuralschema.Structural) *structuralschema.Structural {
26	if s == nil {
27		return nil
28	}
29	schema, ok := s.Properties[field]
30	if ok {
31		return &schema
32	}
33	if s.AdditionalProperties != nil {
34		return s.AdditionalProperties.Structural
35	}
36	return nil
37}
38
39// PruneNonNullableNullsWithoutDefaults removes non-nullable
40// non-defaultable null values from object.
41//
42// Non-nullable nulls that have a default are left alone here and will
43// be defaulted later.
44func PruneNonNullableNullsWithoutDefaults(x interface{}, s *structuralschema.Structural) {
45	switch x := x.(type) {
46	case map[string]interface{}:
47		for k, v := range x {
48			schema := getSchemaForField(k, s)
49			if isNonNullableNonDefaultableNull(v, schema) {
50				delete(x, k)
51			} else {
52				PruneNonNullableNullsWithoutDefaults(v, schema)
53			}
54		}
55	case []interface{}:
56		var schema *structuralschema.Structural
57		if s != nil {
58			schema = s.Items
59		}
60		for i := range x {
61			PruneNonNullableNullsWithoutDefaults(x[i], schema)
62		}
63	default:
64		// scalars, do nothing
65	}
66}
67