Zack Williams | e940c7a | 2019-08-21 14:25:39 -0700 | [diff] [blame] | 1 | /* |
| 2 | Copyright 2014 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 meta |
| 18 | |
| 19 | import ( |
| 20 | "fmt" |
| 21 | |
| 22 | "k8s.io/apimachinery/pkg/runtime/schema" |
| 23 | utilerrors "k8s.io/apimachinery/pkg/util/errors" |
| 24 | ) |
| 25 | |
| 26 | // FirstHitRESTMapper is a wrapper for multiple RESTMappers which returns the |
| 27 | // first successful result for the singular requests |
| 28 | type FirstHitRESTMapper struct { |
| 29 | MultiRESTMapper |
| 30 | } |
| 31 | |
| 32 | func (m FirstHitRESTMapper) String() string { |
| 33 | return fmt.Sprintf("FirstHitRESTMapper{\n\t%v\n}", m.MultiRESTMapper) |
| 34 | } |
| 35 | |
| 36 | func (m FirstHitRESTMapper) ResourceFor(resource schema.GroupVersionResource) (schema.GroupVersionResource, error) { |
| 37 | errors := []error{} |
| 38 | for _, t := range m.MultiRESTMapper { |
| 39 | ret, err := t.ResourceFor(resource) |
| 40 | if err == nil { |
| 41 | return ret, nil |
| 42 | } |
| 43 | errors = append(errors, err) |
| 44 | } |
| 45 | |
| 46 | return schema.GroupVersionResource{}, collapseAggregateErrors(errors) |
| 47 | } |
| 48 | |
| 49 | func (m FirstHitRESTMapper) KindFor(resource schema.GroupVersionResource) (schema.GroupVersionKind, error) { |
| 50 | errors := []error{} |
| 51 | for _, t := range m.MultiRESTMapper { |
| 52 | ret, err := t.KindFor(resource) |
| 53 | if err == nil { |
| 54 | return ret, nil |
| 55 | } |
| 56 | errors = append(errors, err) |
| 57 | } |
| 58 | |
| 59 | return schema.GroupVersionKind{}, collapseAggregateErrors(errors) |
| 60 | } |
| 61 | |
| 62 | // RESTMapping provides the REST mapping for the resource based on the |
| 63 | // kind and version. This implementation supports multiple REST schemas and |
| 64 | // return the first match. |
| 65 | func (m FirstHitRESTMapper) RESTMapping(gk schema.GroupKind, versions ...string) (*RESTMapping, error) { |
| 66 | errors := []error{} |
| 67 | for _, t := range m.MultiRESTMapper { |
| 68 | ret, err := t.RESTMapping(gk, versions...) |
| 69 | if err == nil { |
| 70 | return ret, nil |
| 71 | } |
| 72 | errors = append(errors, err) |
| 73 | } |
| 74 | |
| 75 | return nil, collapseAggregateErrors(errors) |
| 76 | } |
| 77 | |
| 78 | // collapseAggregateErrors returns the minimal errors. it handles empty as nil, handles one item in a list |
| 79 | // by returning the item, and collapses all NoMatchErrors to a single one (since they should all be the same) |
| 80 | func collapseAggregateErrors(errors []error) error { |
| 81 | if len(errors) == 0 { |
| 82 | return nil |
| 83 | } |
| 84 | if len(errors) == 1 { |
| 85 | return errors[0] |
| 86 | } |
| 87 | |
| 88 | allNoMatchErrors := true |
| 89 | for _, err := range errors { |
| 90 | allNoMatchErrors = allNoMatchErrors && IsNoMatchError(err) |
| 91 | } |
| 92 | if allNoMatchErrors { |
| 93 | return errors[0] |
| 94 | } |
| 95 | |
| 96 | return utilerrors.NewAggregate(errors) |
| 97 | } |