golang中命令行库cobra的使用方法示例

> go get -v github.com/spf13/cobra/cobra

src> ../bin/cobra.exe init demo Your Cobra application is ready atC:/Users/liubo5/Desktop/transcoding_tool/src/demoGive it a try by going there and running `go run main.go`Add commands to it by running `cobra add [cmdname]`

package impimport( "fmt")func Show(name string, age int) { fmt.Printf("My Name is %s, My age is %d/n", name, age)}

// Copyright © 2016 NAME HERE <EMAIL ADDRESS>//// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at////  http://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License.package mainimport "demo/cmd"func main() { cmd.Execute()}

// Copyright © 2016 NAME HERE <EMAIL ADDRESS>//// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at////  http://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License.package cmdimport ( "fmt" "os" "github.com/spf13/cobra" "github.com/spf13/viper")var cfgFile string// RootCmd represents the base command when called without any subcommandsvar RootCmd = &cobra.Command{ Use: "demo", Short: "A brief description of your application", Long: `A longer description that spans multiple lines and likely containsexamples and usage of using your application. For example:Cobra is a CLI library for Go that empowers applications.This application is a tool to generate the needed filesto quickly create a Cobra application.`,// Uncomment the following line if your bare application// has an action associated with it:// Run: func(cmd *cobra.Command, args []string) { },}// Execute adds all child commands to the root command sets flags appropriately.// This is called by main.main(). It only needs to happen once to the rootCmd.func Execute() { if err := RootCmd.Execute(); err != nil {  fmt.Println(err)  os.Exit(-1) }}func init() { cobra.OnInitialize(initConfig) // Here you will define your flags and configuration settings. // Cobra supports Persistent Flags, which, if defined here, // will be global for your application. RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.demo.yaml)") // Cobra also supports local flags, which will only run // when this action is called directly. RootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")}// initConfig reads in config file and ENV variables if set.func initConfig() { if cfgFile != "" { // enable ability to specify config file via flag  viper.SetConfigFile(cfgFile) } viper.SetConfigName(".demo") // name of config file (without extension) viper.AddConfigPath("$HOME") // adding home directory as first search path viper.AutomaticEnv()   // read in environment variables that match // If a config file is found, read it in. if err := viper.ReadInConfig(); err == nil {  fmt.Println("Using config file:", viper.ConfigFileUsed()) }}

// Copyright © 2016 NAME HERE <EMAIL ADDRESS>//// Licensed under the Apache License, Version 2.0 (the "License");// you may not use this file except in compliance with the License.// You may obtain a copy of the License at////  http://www.apache.org/licenses/LICENSE-2.0//// Unless required by applicable law or agreed to in writing, software// distributed under the License is distributed on an "AS IS" BASIS,// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.// See the License for the specific language governing permissions and// limitations under the License.package cmdimport ( "fmt" "os" "github.com/spf13/cobra" // "github.com/spf13/viper" "demo/imp")//var cfgFile stringvar name stringvar age int// RootCmd represents the base command when called without any subcommandsvar RootCmd = &cobra.Command{ Use: "demo", Short: "A test demo", Long: `Demo is a test appcation for print things`, // Uncomment the following line if your bare application // has an action associated with it: Run: func(cmd *cobra.Command, args []string) {  if len(name) == 0 {   cmd.Help()   return  }  imp.Show(name, age) },}// Execute adds all child commands to the root command sets flags appropriately.// This is called by main.main(). It only needs to happen once to the rootCmd.func Execute() { if err := RootCmd.Execute(); err != nil {  fmt.Println(err)  os.Exit(-1) }}func init() { // cobra.OnInitialize(initConfig) // Here you will define your flags and configuration settings. // Cobra supports Persistent Flags, which, if defined here, // will be global for your application. // RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.demo.yaml)") // Cobra also supports local flags, which will only run // when this action is called directly. // RootCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle") RootCmd.Flags().StringVarP(&name, "name", "n", "", "person's name") RootCmd.Flags().IntVarP(&age, "age", "a", 0, "person's age")}// initConfig reads in config file and ENV variables if set.//func initConfig() {// if cfgFile != "" { // enable ability to specify config file via flag//  viper.SetConfigFile(cfgFile)// }// viper.SetConfigName(".demo") // name of config file (without extension)// viper.AddConfigPath("$HOME") // adding home directory as first search path// viper.AutomaticEnv()   // read in environment variables that match// // If a config file is found, read it in.// if err := viper.ReadInConfig(); err == nil {//  fmt.Println("Using config file:", viper.ConfigFileUsed())// }//}

src/demo>../../bin/cobra add testtest created at C:/Users/liubo5/Desktop/transcoding_tool/src/demo/cmd/test.go

src/demo>demoDemo is a test appcation for print thingsUsage: demo [flags] demo [command]Available Commands: test  A brief description of your commandFlags: -a, --age int  person's age -h, --help   help for demo -n, --name string person's nameUse "demo [command] --help" for more information about a command.

src/demo>demo test -hA longer description that spans multiple lines and likely contains examplesand usage of using your command. For example:Cobra is a CLI library for Go that empowers applications.This application is a tool to generate the needed filesto quickly create a Cobra application.Usage: demo test [flags]

src/demo>demo tstError: unknown command "tst" for "demo"Did you mean this?  testRun 'demo --help' for usage.unknown command "tst" for "demo"Did you mean this?  test