1/* 2Copyright 2014 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 17// Package verflag defines utility functions to handle command line flags 18// related to version of Kubernetes. 19package verflag 20 21import ( 22 "fmt" 23 "os" 24 "strconv" 25 26 flag "github.com/spf13/pflag" 27 28 "k8s.io/component-base/version" 29) 30 31type versionValue int 32 33const ( 34 VersionFalse versionValue = 0 35 VersionTrue versionValue = 1 36 VersionRaw versionValue = 2 37) 38 39const strRawVersion string = "raw" 40 41func (v *versionValue) IsBoolFlag() bool { 42 return true 43} 44 45func (v *versionValue) Get() interface{} { 46 return versionValue(*v) 47} 48 49func (v *versionValue) Set(s string) error { 50 if s == strRawVersion { 51 *v = VersionRaw 52 return nil 53 } 54 boolVal, err := strconv.ParseBool(s) 55 if boolVal { 56 *v = VersionTrue 57 } else { 58 *v = VersionFalse 59 } 60 return err 61} 62 63func (v *versionValue) String() string { 64 if *v == VersionRaw { 65 return strRawVersion 66 } 67 return fmt.Sprintf("%v", bool(*v == VersionTrue)) 68} 69 70// The type of the flag as required by the pflag.Value interface 71func (v *versionValue) Type() string { 72 return "version" 73} 74 75func VersionVar(p *versionValue, name string, value versionValue, usage string) { 76 *p = value 77 flag.Var(p, name, usage) 78 // "--version" will be treated as "--version=true" 79 flag.Lookup(name).NoOptDefVal = "true" 80} 81 82func Version(name string, value versionValue, usage string) *versionValue { 83 p := new(versionValue) 84 VersionVar(p, name, value, usage) 85 return p 86} 87 88const versionFlagName = "version" 89 90var ( 91 versionFlag = Version(versionFlagName, VersionFalse, "Print version information and quit") 92 programName = "Kubernetes" 93) 94 95// AddFlags registers this package's flags on arbitrary FlagSets, such that they point to the 96// same value as the global flags. 97func AddFlags(fs *flag.FlagSet) { 98 fs.AddFlag(flag.Lookup(versionFlagName)) 99} 100 101// PrintAndExitIfRequested will check if the -version flag was passed 102// and, if so, print the version and exit. 103func PrintAndExitIfRequested() { 104 if *versionFlag == VersionRaw { 105 fmt.Printf("%#v\n", version.Get()) 106 os.Exit(0) 107 } else if *versionFlag == VersionTrue { 108 fmt.Printf("%s %s\n", programName, version.Get()) 109 os.Exit(0) 110 } 111} 112