Scott Baker | e7144bc | 2019-10-01 14:16:47 -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 | /* |
| 18 | Package auth defines a file format for holding authentication |
| 19 | information needed by clients of Kubernetes. Typically, |
| 20 | a Kubernetes cluster will put auth info for the admin in a known |
| 21 | location when it is created, and will (soon) put it in a known |
| 22 | location within a Container's file tree for Containers that |
| 23 | need access to the Kubernetes API. |
| 24 | |
| 25 | Having a defined format allows: |
| 26 | - clients to be implemented in multiple languages |
| 27 | - applications which link clients to be portable across |
| 28 | clusters with different authentication styles (e.g. |
| 29 | some may use SSL Client certs, others may not, etc) |
| 30 | - when the format changes, applications only |
| 31 | need to update this code. |
| 32 | |
| 33 | The file format is json, marshalled from a struct authcfg.Info. |
| 34 | |
| 35 | Clinet libraries in other languages should use the same format. |
| 36 | |
| 37 | It is not intended to store general preferences, such as default |
| 38 | namespace, output options, etc. CLIs (such as kubectl) and UIs should |
| 39 | develop their own format and may wish to inline the authcfg.Info type. |
| 40 | |
| 41 | The authcfg.Info is just a file format. It is distinct from |
| 42 | client.Config which holds options for creating a client.Client. |
| 43 | Helper functions are provided in this package to fill in a |
| 44 | client.Client from an authcfg.Info. |
| 45 | |
| 46 | Example: |
| 47 | |
| 48 | import ( |
| 49 | "pkg/client" |
| 50 | "pkg/client/auth" |
| 51 | ) |
| 52 | |
| 53 | info, err := auth.LoadFromFile(filename) |
| 54 | if err != nil { |
| 55 | // handle error |
| 56 | } |
| 57 | clientConfig = client.Config{} |
| 58 | clientConfig.Host = "example.com:4901" |
| 59 | clientConfig = info.MergeWithConfig() |
| 60 | client := client.New(clientConfig) |
| 61 | client.Pods(ns).List() |
| 62 | */ |
| 63 | package auth |
| 64 | |
| 65 | // TODO: need a way to rotate Tokens. Therefore, need a way for client object to be reset when the authcfg is updated. |
| 66 | import ( |
| 67 | "encoding/json" |
| 68 | "io/ioutil" |
| 69 | "os" |
| 70 | |
| 71 | restclient "k8s.io/client-go/rest" |
| 72 | ) |
| 73 | |
| 74 | // Info holds Kubernetes API authorization config. It is intended |
| 75 | // to be read/written from a file as a JSON object. |
| 76 | type Info struct { |
| 77 | User string |
| 78 | Password string |
| 79 | CAFile string |
| 80 | CertFile string |
| 81 | KeyFile string |
| 82 | BearerToken string |
| 83 | Insecure *bool |
| 84 | } |
| 85 | |
| 86 | // LoadFromFile parses an Info object from a file path. |
| 87 | // If the file does not exist, then os.IsNotExist(err) == true |
| 88 | func LoadFromFile(path string) (*Info, error) { |
| 89 | var info Info |
| 90 | if _, err := os.Stat(path); os.IsNotExist(err) { |
| 91 | return nil, err |
| 92 | } |
| 93 | data, err := ioutil.ReadFile(path) |
| 94 | if err != nil { |
| 95 | return nil, err |
| 96 | } |
| 97 | err = json.Unmarshal(data, &info) |
| 98 | if err != nil { |
| 99 | return nil, err |
| 100 | } |
| 101 | return &info, err |
| 102 | } |
| 103 | |
| 104 | // MergeWithConfig returns a copy of a client.Config with values from the Info. |
| 105 | // The fields of client.Config with a corresponding field in the Info are set |
| 106 | // with the value from the Info. |
| 107 | func (info Info) MergeWithConfig(c restclient.Config) (restclient.Config, error) { |
| 108 | var config restclient.Config = c |
| 109 | config.Username = info.User |
| 110 | config.Password = info.Password |
| 111 | config.CAFile = info.CAFile |
| 112 | config.CertFile = info.CertFile |
| 113 | config.KeyFile = info.KeyFile |
| 114 | config.BearerToken = info.BearerToken |
| 115 | if info.Insecure != nil { |
| 116 | config.Insecure = *info.Insecure |
| 117 | } |
| 118 | return config, nil |
| 119 | } |
| 120 | |
| 121 | func (info Info) Complete() bool { |
| 122 | return len(info.User) > 0 || |
| 123 | len(info.CertFile) > 0 || |
| 124 | len(info.BearerToken) > 0 |
| 125 | } |