diff options
Diffstat (limited to 'vendor/github.com/spf13/cobra/README.md')
| -rw-r--r-- | vendor/github.com/spf13/cobra/README.md | 442 |
1 files changed, 207 insertions, 235 deletions
diff --git a/vendor/github.com/spf13/cobra/README.md b/vendor/github.com/spf13/cobra/README.md index a38137b25..da9aa881e 100644 --- a/vendor/github.com/spf13/cobra/README.md +++ b/vendor/github.com/spf13/cobra/README.md @@ -117,14 +117,6 @@ Flag functionality is provided by the [pflag library](https://github.com/spf13/pflag), a fork of the flag standard library which maintains the same interface while adding POSIX compliance. -## Usage - -Cobra works by creating a set of commands and then organizing them into a tree. -The tree defines the structure of the application. - -Once each command is defined with its corresponding flags, then the -tree is assigned to the commander which is finally executed. - # Installing Using Cobra is easy. First, use `go get` to install the latest version of the library. This command will install the `cobra` generator executable @@ -159,17 +151,17 @@ In a Cobra app, typically the main.go file is very bare. It serves one purpose: package main import ( - "fmt" - "os" + "fmt" + "os" - "{pathToYourApp}/cmd" + "{pathToYourApp}/cmd" ) func main() { - if err := cmd.RootCmd.Execute(); err != nil { - fmt.Println(err) - os.Exit(1) - } + if err := cmd.RootCmd.Execute(); err != nil { + fmt.Println(err) + os.Exit(1) + } } ``` @@ -285,14 +277,14 @@ Ideally you place this in app/cmd/root.go: ```go var RootCmd = &cobra.Command{ - Use: "hugo", - Short: "Hugo is a very fast static site generator", - Long: `A Fast and Flexible Static Site Generator built with + Use: "hugo", + Short: "Hugo is a very fast static site generator", + Long: `A Fast and Flexible Static Site Generator built with love by spf13 and friends in Go. Complete documentation is available at http://hugo.spf13.com`, - Run: func(cmd *cobra.Command, args []string) { - // Do Stuff Here - }, + Run: func(cmd *cobra.Command, args []string) { + // Do Stuff Here + }, } ``` @@ -302,54 +294,54 @@ For example cmd/root.go: ```go import ( - "fmt" - "os" + "fmt" + "os" - homedir "github.com/mitchellh/go-homedir" - "github.com/spf13/cobra" - "github.com/spf13/viper" + homedir "github.com/mitchellh/go-homedir" + "github.com/spf13/cobra" + "github.com/spf13/viper" ) func init() { - cobra.OnInitialize(initConfig) - RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)") - RootCmd.PersistentFlags().StringVarP(&projectBase, "projectbase", "b", "", "base project directory eg. github.com/spf13/") - RootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "Author name for copyright attribution") - RootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "Name of license for the project (can provide `licensetext` in config)") - RootCmd.PersistentFlags().Bool("viper", true, "Use Viper for configuration") - viper.BindPFlag("author", RootCmd.PersistentFlags().Lookup("author")) - viper.BindPFlag("projectbase", RootCmd.PersistentFlags().Lookup("projectbase")) - viper.BindPFlag("useViper", RootCmd.PersistentFlags().Lookup("viper")) - viper.SetDefault("author", "NAME HERE <EMAIL ADDRESS>") - viper.SetDefault("license", "apache") + cobra.OnInitialize(initConfig) + RootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)") + RootCmd.PersistentFlags().StringVarP(&projectBase, "projectbase", "b", "", "base project directory eg. github.com/spf13/") + RootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "Author name for copyright attribution") + RootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "Name of license for the project (can provide `licensetext` in config)") + RootCmd.PersistentFlags().Bool("viper", true, "Use Viper for configuration") + viper.BindPFlag("author", RootCmd.PersistentFlags().Lookup("author")) + viper.BindPFlag("projectbase", RootCmd.PersistentFlags().Lookup("projectbase")) + viper.BindPFlag("useViper", RootCmd.PersistentFlags().Lookup("viper")) + viper.SetDefault("author", "NAME HERE <EMAIL ADDRESS>") + viper.SetDefault("license", "apache") } func Execute() { - RootCmd.Execute() + RootCmd.Execute() } func initConfig() { // Don't forget to read config either from cfgFile or from home directory! - if cfgFile != "" { - // Use config file from the flag. - viper.SetConfigFile(cfgFile) - } else { - // Find home directory. - home, err := homedir.Dir() - if err != nil { - fmt.Println(err) - os.Exit(1) - } - - // Search config in home directory with name ".cobra" (without extension). - viper.AddConfigPath(home) - viper.SetConfigName(".cobra") - } - - if err := viper.ReadInConfig(); err != nil { - fmt.Println("Can't read config:", err) - os.Exit(1) - } + if cfgFile != "" { + // Use config file from the flag. + viper.SetConfigFile(cfgFile) + } else { + // Find home directory. + home, err := homedir.Dir() + if err != nil { + fmt.Println(err) + os.Exit(1) + } + + // Search config in home directory with name ".cobra" (without extension). + viper.AddConfigPath(home) + viper.SetConfigName(".cobra") + } + + if err := viper.ReadInConfig(); err != nil { + fmt.Println("Can't read config:", err) + os.Exit(1) + } } ``` @@ -364,17 +356,17 @@ In a Cobra app, typically the main.go file is very bare. It serves, one purpose, package main import ( - "fmt" - "os" + "fmt" + "os" - "{pathToYourApp}/cmd" + "{pathToYourApp}/cmd" ) func main() { - if err := cmd.RootCmd.Execute(); err != nil { - fmt.Println(err) - os.Exit(1) - } + if err := cmd.RootCmd.Execute(); err != nil { + fmt.Println(err) + os.Exit(1) + } } ``` @@ -390,21 +382,21 @@ populate it with the following: package cmd import ( - "github.com/spf13/cobra" - "fmt" + "github.com/spf13/cobra" + "fmt" ) func init() { - RootCmd.AddCommand(versionCmd) + RootCmd.AddCommand(versionCmd) } var versionCmd = &cobra.Command{ - Use: "version", - Short: "Print the version number of Hugo", - Long: `All software has versions. This is Hugo's`, - Run: func(cmd *cobra.Command, args []string) { - fmt.Println("Hugo Static Site Generator v0.9 -- HEAD") - }, + Use: "version", + Short: "Print the version number of Hugo", + Long: `All software has versions. This is Hugo's`, + Run: func(cmd *cobra.Command, args []string) { + fmt.Println("Hugo Static Site Generator v0.9 -- HEAD") + }, } ``` @@ -419,19 +411,6 @@ root, but commands can be attached at any level. RootCmd.AddCommand(versionCmd) ``` -### Remove a command from its parent - -Removing a command is not a common action in simple programs, but it allows 3rd -parties to customize an existing command tree. - -In this example, we remove the existing `VersionCmd` command of an existing -root command, and we replace it with our own version: - -```go -mainlib.RootCmd.RemoveCommand(mainlib.VersionCmd) -mainlib.RootCmd.AddCommand(versionCmd) -``` - ## Working with Flags Flags provide modifiers to control how the action command operates. @@ -474,8 +453,8 @@ You can also bind your flags with [viper](https://github.com/spf13/viper): var author string func init() { - RootCmd.PersistentFlags().StringVar(&author, "author", "YOUR NAME", "Author name for copyright attribution") - viper.BindPFlag("author", RootCmd.PersistentFlags().Lookup("author")) + RootCmd.PersistentFlags().StringVar(&author, "author", "YOUR NAME", "Author name for copyright attribution") + viper.BindPFlag("author", RootCmd.PersistentFlags().Lookup("author")) } ``` @@ -487,32 +466,37 @@ More in [viper documentation](https://github.com/spf13/viper#working-with-flags) ## Positional and Custom Arguments -Validation of positional arguments can be specified using the `Args` field. +Validation of positional arguments can be specified using the `Args` field +of `Command`. -The follow validators are built in: +The following validators are built in: - `NoArgs` - the command will report an error if there are any positional args. - `ArbitraryArgs` - the command will accept any args. -- `OnlyValidArgs` - the command will report an error if there are any positional args that are not in the ValidArgs list. +- `OnlyValidArgs` - the command will report an error if there are any positional args that are not in the `ValidArgs` field of `Command`. - `MinimumNArgs(int)` - the command will report an error if there are not at least N positional args. - `MaximumNArgs(int)` - the command will report an error if there are more than N positional args. - `ExactArgs(int)` - the command will report an error if there are not exactly N positional args. - `RangeArgs(min, max)` - the command will report an error if the number of args is not between the minimum and maximum number of expected args. -A custom validator can be provided like this: +An example of setting the custom validator: ```go - -Args: func validColorArgs(cmd *cobra.Command, args []string) error { - if err := cli.RequiresMinArgs(1)(cmd, args); err != nil { - return err - } - if myapp.IsValidColor(args[0]) { - return nil - } - return fmt.Errorf("Invalid color specified: %s", args[0]) +var cmd = &cobra.Command{ + Short: "hello", + Args: func(cmd *cobra.Command, args []string) error { + if len(args) < 1 { + return errors.New("requires at least one arg") + } + if myapp.IsValidColor(args[0]) { + return nil + } + return fmt.Errorf("invalid color specified: %s", args[0]) + }, + Run: func(cmd *cobra.Command, args []string) { + fmt.Println("Hello, World!") + }, } - ``` ## Example @@ -530,56 +514,56 @@ More documentation about flags is available at https://github.com/spf13/pflag package main import ( - "fmt" - "strings" + "fmt" + "strings" - "github.com/spf13/cobra" + "github.com/spf13/cobra" ) func main() { + var echoTimes int + + var cmdPrint = &cobra.Command{ + Use: "print [string to print]", + Short: "Print anything to the screen", + Long: `print is for printing anything back to the screen. +For many years people have printed back to the screen.`, + Args: cobra.MinimumNArgs(1), + Run: func(cmd *cobra.Command, args []string) { + fmt.Println("Print: " + strings.Join(args, " ")) + }, + } + + var cmdEcho = &cobra.Command{ + Use: "echo [string to echo]", + Short: "Echo anything to the screen", + Long: `echo is for echoing anything back. +Echo works a lot like print, except it has a child command.`, + Args: cobra.MinimumNArgs(1), + Run: func(cmd *cobra.Command, args []string) { + fmt.Println("Print: " + strings.Join(args, " ")) + }, + } - var echoTimes int - - var cmdPrint = &cobra.Command{ - Use: "print [string to print]", - Short: "Print anything to the screen", - Long: `print is for printing anything back to the screen. - For many years people have printed back to the screen. - `, - Run: func(cmd *cobra.Command, args []string) { - fmt.Println("Print: " + strings.Join(args, " ")) - }, - } - - var cmdEcho = &cobra.Command{ - Use: "echo [string to echo]", - Short: "Echo anything to the screen", - Long: `echo is for echoing anything back. - Echo works a lot like print, except it has a child command. - `, - Run: func(cmd *cobra.Command, args []string) { - fmt.Println("Print: " + strings.Join(args, " ")) - }, - } - - var cmdTimes = &cobra.Command{ - Use: "times [# times] [string to echo]", - Short: "Echo anything to the screen more times", - Long: `echo things multiple times back to the user by providing - a count and a string.`, - Run: func(cmd *cobra.Command, args []string) { - for i := 0; i < echoTimes; i++ { - fmt.Println("Echo: " + strings.Join(args, " ")) - } - }, - } - - cmdTimes.Flags().IntVarP(&echoTimes, "times", "t", 1, "times to echo the input") - - var rootCmd = &cobra.Command{Use: "app"} - rootCmd.AddCommand(cmdPrint, cmdEcho) - cmdEcho.AddCommand(cmdTimes) - rootCmd.Execute() + var cmdTimes = &cobra.Command{ + Use: "times [# times] [string to echo]", + Short: "Echo anything to the screen more times", + Long: `echo things multiple times back to the user by providing +a count and a string.`, + Args: cobra.MinimumNArgs(1), + Run: func(cmd *cobra.Command, args []string) { + for i := 0; i < echoTimes; i++ { + fmt.Println("Echo: " + strings.Join(args, " ")) + } + }, + } + + cmdTimes.Flags().IntVarP(&echoTimes, "times", "t", 1, "times to echo the input") + + var rootCmd = &cobra.Command{Use: "app"} + rootCmd.AddCommand(cmdPrint, cmdEcho) + cmdEcho.AddCommand(cmdTimes) + rootCmd.Execute() } ``` @@ -665,16 +649,16 @@ The default help command is ```go func (c *Command) initHelp() { - if c.helpCommand == nil { - c.helpCommand = &Command{ - Use: "help [command]", - Short: "Help about any command", - Long: `Help provides help for any command in the application. + if c.helpCommand == nil { + c.helpCommand = &Command{ + Use: "help [command]", + Short: "Help about any command", + Long: `Help provides help for any command in the application. Simply type ` + c.Name() + ` help [path to command] for full details.`, - Run: c.HelpFunc(), - } - } - c.AddCommand(c.helpCommand) + Run: c.HelpFunc(), + } + } + c.AddCommand(c.helpCommand) } ``` @@ -682,9 +666,7 @@ You can provide your own command, function or template through the following met ```go command.SetHelpCommand(cmd *Command) - command.SetHelpFunc(f func(*Command, []string)) - command.SetHelpTemplate(s string) ``` @@ -750,8 +732,8 @@ The default usage function is: ```go return func(c *Command) error { - err := tmpl(c.Out(), c.UsageTemplate(), c) - return err + err := tmpl(c.Out(), c.UsageTemplate(), c) + return err } ``` @@ -779,57 +761,57 @@ An example of two commands which use all of these features is below. When the s package main import ( - "fmt" + "fmt" - "github.com/spf13/cobra" + "github.com/spf13/cobra" ) func main() { - var rootCmd = &cobra.Command{ - Use: "root [sub]", - Short: "My root command", - PersistentPreRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside rootCmd PersistentPreRun with args: %v\n", args) - }, - PreRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside rootCmd PreRun with args: %v\n", args) - }, - Run: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside rootCmd Run with args: %v\n", args) - }, - PostRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside rootCmd PostRun with args: %v\n", args) - }, - PersistentPostRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside rootCmd PersistentPostRun with args: %v\n", args) - }, - } - - var subCmd = &cobra.Command{ - Use: "sub [no options!]", - Short: "My subcommand", - PreRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside subCmd PreRun with args: %v\n", args) - }, - Run: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside subCmd Run with args: %v\n", args) - }, - PostRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside subCmd PostRun with args: %v\n", args) - }, - PersistentPostRun: func(cmd *cobra.Command, args []string) { - fmt.Printf("Inside subCmd PersistentPostRun with args: %v\n", args) - }, - } - - rootCmd.AddCommand(subCmd) - - rootCmd.SetArgs([]string{""}) - _ = rootCmd.Execute() - fmt.Print("\n") - rootCmd.SetArgs([]string{"sub", "arg1", "arg2"}) - _ = rootCmd.Execute() + var rootCmd = &cobra.Command{ + Use: "root [sub]", + Short: "My root command", + PersistentPreRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside rootCmd PersistentPreRun with args: %v\n", args) + }, + PreRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside rootCmd PreRun with args: %v\n", args) + }, + Run: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside rootCmd Run with args: %v\n", args) + }, + PostRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside rootCmd PostRun with args: %v\n", args) + }, + PersistentPostRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside rootCmd PersistentPostRun with args: %v\n", args) + }, + } + + var subCmd = &cobra.Command{ + Use: "sub [no options!]", + Short: "My subcommand", + PreRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside subCmd PreRun with args: %v\n", args) + }, + Run: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside subCmd Run with args: %v\n", args) + }, + PostRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside subCmd PostRun with args: %v\n", args) + }, + PersistentPostRun: func(cmd *cobra.Command, args []string) { + fmt.Printf("Inside subCmd PersistentPostRun with args: %v\n", args) + }, + } + + rootCmd.AddCommand(subCmd) + + rootCmd.SetArgs([]string{""}) + rootCmd.Execute() + fmt.Println() + rootCmd.SetArgs([]string{"sub", "arg1", "arg2"}) + rootCmd.Execute() } ``` @@ -855,28 +837,28 @@ command. package main import ( - "errors" - "log" + "errors" + "log" - "github.com/spf13/cobra" + "github.com/spf13/cobra" ) func main() { - var rootCmd = &cobra.Command{ - Use: "hugo", - Short: "Hugo is a very fast static site generator", - Long: `A Fast and Flexible Static Site Generator built with - love by spf13 and friends in Go. - Complete documentation is available at http://hugo.spf13.com`, - RunE: func(cmd *cobra.Command, args []string) error { - // Do Stuff Here - return errors.New("some random error") - }, - } - - if err := rootCmd.Execute(); err != nil { - log.Fatal(err) - } + var rootCmd = &cobra.Command{ + Use: "hugo", + Short: "Hugo is a very fast static site generator", + Long: `A Fast and Flexible Static Site Generator built with +love by spf13 and friends in Go. +Complete documentation is available at http://hugo.spf13.com`, + RunE: func(cmd *cobra.Command, args []string) error { + // Do Stuff Here + return errors.New("some random error") + }, + } + + if err := rootCmd.Execute(); err != nil { + log.Fatal(err) + } } ``` @@ -932,16 +914,6 @@ Cobra can generate a man page based on the subcommands, flags, etc. A simple exa Cobra can generate a bash-completion file. If you add more information to your command, these completions can be amazingly powerful and flexible. Read more about it in [Bash Completions](bash_completions.md). -## Debugging - -Cobra provides a ‘DebugFlags’ method on a command which, when called, will print -out everything Cobra knows about the flags for each command. - -### Example - -```go -command.DebugFlags() -``` ## Extensions |