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diff --git a/vendor/github.com/spf13/cobra/user_guide.md b/vendor/github.com/spf13/cobra/user_guide.md deleted file mode 100644 index 85201d840..000000000 --- a/vendor/github.com/spf13/cobra/user_guide.md +++ /dev/null @@ -1,726 +0,0 @@ -# User Guide - -While you are welcome to provide your own organization, typically a Cobra-based -application will follow the following organizational structure: - -``` - ▾ appName/ - ▾ cmd/ - add.go - your.go - commands.go - here.go - main.go -``` - -In a Cobra app, typically the main.go file is very bare. It serves one purpose: initializing Cobra. - -```go -package main - -import ( - "{pathToYourApp}/cmd" -) - -func main() { - cmd.Execute() -} -``` - -## Using the Cobra Generator - -Cobra-CLI is its own program that will create your application and add any -commands you want. It's the easiest way to incorporate Cobra into your application. - -For complete details on using the Cobra generator, please refer to [The Cobra-CLI Generator README](https://github.com/spf13/cobra-cli/blob/main/README.md) - -## Using the Cobra Library - -To manually implement Cobra you need to create a bare main.go file and a rootCmd file. -You will optionally provide additional commands as you see fit. - -### Create rootCmd - -Cobra doesn't require any special constructors. Simply create your commands. - -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 - love by spf13 and friends in Go. - Complete documentation is available at https://gohugo.io/documentation/`, - Run: func(cmd *cobra.Command, args []string) { - // Do Stuff Here - }, -} - -func Execute() { - if err := rootCmd.Execute(); err != nil { - fmt.Fprintln(os.Stderr, err) - os.Exit(1) - } -} -``` - -You will additionally define flags and handle configuration in your init() function. - -For example cmd/root.go: - -```go -package cmd - -import ( - "fmt" - "os" - - "github.com/spf13/cobra" - "github.com/spf13/viper" -) - -var ( - // Used for flags. - cfgFile string - userLicense string - - rootCmd = &cobra.Command{ - Use: "cobra-cli", - Short: "A generator for Cobra based Applications", - Long: `Cobra is a CLI library for Go that empowers applications. -This application is a tool to generate the needed files -to quickly create a Cobra application.`, - } -) - -// Execute executes the root command. -func Execute() error { - return rootCmd.Execute() -} - -func init() { - cobra.OnInitialize(initConfig) - - rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)") - rootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "author name for copyright attribution") - rootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "name of license for the project") - rootCmd.PersistentFlags().Bool("viper", true, "use Viper for configuration") - viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author")) - viper.BindPFlag("useViper", rootCmd.PersistentFlags().Lookup("viper")) - viper.SetDefault("author", "NAME HERE <EMAIL ADDRESS>") - viper.SetDefault("license", "apache") - - rootCmd.AddCommand(addCmd) - rootCmd.AddCommand(initCmd) -} - -func initConfig() { - if cfgFile != "" { - // Use config file from the flag. - viper.SetConfigFile(cfgFile) - } else { - // Find home directory. - home, err := os.UserHomeDir() - cobra.CheckErr(err) - - // Search config in home directory with name ".cobra" (without extension). - viper.AddConfigPath(home) - viper.SetConfigType("yaml") - viper.SetConfigName(".cobra") - } - - viper.AutomaticEnv() - - if err := viper.ReadInConfig(); err == nil { - fmt.Println("Using config file:", viper.ConfigFileUsed()) - } -} -``` - -### Create your main.go - -With the root command you need to have your main function execute it. -Execute should be run on the root for clarity, though it can be called on any command. - -In a Cobra app, typically the main.go file is very bare. It serves one purpose: to initialize Cobra. - -```go -package main - -import ( - "{pathToYourApp}/cmd" -) - -func main() { - cmd.Execute() -} -``` - -### Create additional commands - -Additional commands can be defined and typically are each given their own file -inside of the cmd/ directory. - -If you wanted to create a version command you would create cmd/version.go and -populate it with the following: - -```go -package cmd - -import ( - "fmt" - - "github.com/spf13/cobra" -) - -func init() { - 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") - }, -} -``` - -### Organizing subcommands - -A command may have subcommands which in turn may have other subcommands. This is achieved by using -`AddCommand`. In some cases, especially in larger applications, each subcommand may be defined in -its own go package. - -The suggested approach is for the parent command to use `AddCommand` to add its most immediate -subcommands. For example, consider the following directory structure: - -```text -├── cmd -│ ├── root.go -│ └── sub1 -│ ├── sub1.go -│ └── sub2 -│ ├── leafA.go -│ ├── leafB.go -│ └── sub2.go -└── main.go -``` - -In this case: - -* The `init` function of `root.go` adds the command defined in `sub1.go` to the root command. -* The `init` function of `sub1.go` adds the command defined in `sub2.go` to the sub1 command. -* The `init` function of `sub2.go` adds the commands defined in `leafA.go` and `leafB.go` to the - sub2 command. - -This approach ensures the subcommands are always included at compile time while avoiding cyclic -references. - -### Returning and handling errors - -If you wish to return an error to the caller of a command, `RunE` can be used. - -```go -package cmd - -import ( - "fmt" - - "github.com/spf13/cobra" -) - -func init() { - rootCmd.AddCommand(tryCmd) -} - -var tryCmd = &cobra.Command{ - Use: "try", - Short: "Try and possibly fail at something", - RunE: func(cmd *cobra.Command, args []string) error { - if err := someFunc(); err != nil { - return err - } - return nil - }, -} -``` - -The error can then be caught at the execute function call. - -## Working with Flags - -Flags provide modifiers to control how the action command operates. - -### Assign flags to a command - -Since the flags are defined and used in different locations, we need to -define a variable outside with the correct scope to assign the flag to -work with. - -```go -var Verbose bool -var Source string -``` - -There are two different approaches to assign a flag. - -### Persistent Flags - -A flag can be 'persistent', meaning that this flag will be available to the -command it's assigned to as well as every command under that command. For -global flags, assign a flag as a persistent flag on the root. - -```go -rootCmd.PersistentFlags().BoolVarP(&Verbose, "verbose", "v", false, "verbose output") -``` - -### Local Flags - -A flag can also be assigned locally, which will only apply to that specific command. - -```go -localCmd.Flags().StringVarP(&Source, "source", "s", "", "Source directory to read from") -``` - -### Local Flag on Parent Commands - -By default, Cobra only parses local flags on the target command, and any local flags on -parent commands are ignored. By enabling `Command.TraverseChildren`, Cobra will -parse local flags on each command before executing the target command. - -```go -command := cobra.Command{ - Use: "print [OPTIONS] [COMMANDS]", - TraverseChildren: true, -} -``` - -### Bind Flags with Config - -You can also bind your flags with [viper](https://github.com/spf13/viper): -```go -var author string - -func init() { - rootCmd.PersistentFlags().StringVar(&author, "author", "YOUR NAME", "Author name for copyright attribution") - viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author")) -} -``` - -In this example, the persistent flag `author` is bound with `viper`. -**Note**: the variable `author` will not be set to the value from config, -when the `--author` flag is provided by user. - -More in [viper documentation](https://github.com/spf13/viper#working-with-flags). - -### Required flags - -Flags are optional by default. If instead you wish your command to report an error -when a flag has not been set, mark it as required: -```go -rootCmd.Flags().StringVarP(&Region, "region", "r", "", "AWS region (required)") -rootCmd.MarkFlagRequired("region") -``` - -Or, for persistent flags: -```go -rootCmd.PersistentFlags().StringVarP(&Region, "region", "r", "", "AWS region (required)") -rootCmd.MarkPersistentFlagRequired("region") -``` - -### Flag Groups - -If you have different flags that must be provided together (e.g. if they provide the `--username` flag they MUST provide the `--password` flag as well) then -Cobra can enforce that requirement: -```go -rootCmd.Flags().StringVarP(&u, "username", "u", "", "Username (required if password is set)") -rootCmd.Flags().StringVarP(&pw, "password", "p", "", "Password (required if username is set)") -rootCmd.MarkFlagsRequiredTogether("username", "password") -``` - -You can also prevent different flags from being provided together if they represent mutually -exclusive options such as specifying an output format as either `--json` or `--yaml` but never both: -```go -rootCmd.Flags().BoolVar(&ofJson, "json", false, "Output in JSON") -rootCmd.Flags().BoolVar(&ofYaml, "yaml", false, "Output in YAML") -rootCmd.MarkFlagsMutuallyExclusive("json", "yaml") -``` - -In both of these cases: - - both local and persistent flags can be used - - **NOTE:** the group is only enforced on commands where every flag is defined - - a flag may appear in multiple groups - - a group may contain any number of flags - -## Positional and Custom Arguments - -Validation of positional arguments can be specified using the `Args` field of `Command`. -The following validators are built in: - -- Number of arguments: - - `NoArgs` - report an error if there are any positional args. - - `ArbitraryArgs` - accept any number of args. - - `MinimumNArgs(int)` - report an error if less than N positional args are provided. - - `MaximumNArgs(int)` - report an error if more than N positional args are provided. - - `ExactArgs(int)` - report an error if there are not exactly N positional args. - - `RangeArgs(min, max)` - report an error if the number of args is not between `min` and `max`. -- Content of the arguments: - - `OnlyValidArgs` - report an error if there are any positional args not specified in the `ValidArgs` field of `Command`, which can optionally be set to a list of valid values for positional args. - -If `Args` is undefined or `nil`, it defaults to `ArbitraryArgs`. - -Moreover, `MatchAll(pargs ...PositionalArgs)` enables combining existing checks with arbitrary other checks. -For instance, if you want to report an error if there are not exactly N positional args OR if there are any positional -args that are not in the `ValidArgs` field of `Command`, you can call `MatchAll` on `ExactArgs` and `OnlyValidArgs`, as -shown below: - -```go -var cmd = &cobra.Command{ - Short: "hello", - Args: cobra.MatchAll(cobra.ExactArgs(2), cobra.OnlyValidArgs), - Run: func(cmd *cobra.Command, args []string) { - fmt.Println("Hello, World!") - }, -} -``` - -It is possible to set any custom validator that satisfies `func(cmd *cobra.Command, args []string) error`. -For example: - -```go -var cmd = &cobra.Command{ - Short: "hello", - Args: func(cmd *cobra.Command, args []string) error { - // Optionally run one of the validators provided by cobra - if err := cobra.MinimumNArgs(1)(cmd, args); err != nil { - return err - } - // Run the custom validation logic - 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 - -In the example below, we have defined three commands. Two are at the top level -and one (cmdTimes) is a child of one of the top commands. In this case the root -is not executable, meaning that a subcommand is required. This is accomplished -by not providing a 'Run' for the 'rootCmd'. - -We have only defined one flag for a single command. - -More documentation about flags is available at https://github.com/spf13/pflag - -```go -package main - -import ( - "fmt" - "strings" - - "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("Echo: " + strings.Join(args, " ")) - }, - } - - var cmdTimes = &cobra.Command{ - Use: "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() -} -``` - -For a more complete example of a larger application, please checkout [Hugo](https://gohugo.io/). - -## Help Command - -Cobra automatically adds a help command to your application when you have subcommands. -This will be called when a user runs 'app help'. Additionally, help will also -support all other commands as input. Say, for instance, you have a command called -'create' without any additional configuration; Cobra will work when 'app help -create' is called. Every command will automatically have the '--help' flag added. - -### Example - -The following output is automatically generated by Cobra. Nothing beyond the -command and flag definitions are needed. - - $ cobra-cli help - - Cobra is a CLI library for Go that empowers applications. - This application is a tool to generate the needed files - to quickly create a Cobra application. - - Usage: - cobra-cli [command] - - Available Commands: - add Add a command to a Cobra Application - completion Generate the autocompletion script for the specified shell - help Help about any command - init Initialize a Cobra Application - - Flags: - -a, --author string author name for copyright attribution (default "YOUR NAME") - --config string config file (default is $HOME/.cobra.yaml) - -h, --help help for cobra-cli - -l, --license string name of license for the project - --viper use Viper for configuration - - Use "cobra-cli [command] --help" for more information about a command. - - -Help is just a command like any other. There is no special logic or behavior -around it. In fact, you can provide your own if you want. - -### Grouping commands in help - -Cobra supports grouping of available commands in the help output. To group commands, each group must be explicitly -defined using `AddGroup()` on the parent command. Then a subcommand can be added to a group using the `GroupID` element -of that subcommand. The groups will appear in the help output in the same order as they are defined using different -calls to `AddGroup()`. If you use the generated `help` or `completion` commands, you can set their group ids using -`SetHelpCommandGroupId()` and `SetCompletionCommandGroupId()` on the root command, respectively. - -### Defining your own help - -You can provide your own Help command or your own template for the default command to use -with the following functions: - -```go -cmd.SetHelpCommand(cmd *Command) -cmd.SetHelpFunc(f func(*Command, []string)) -cmd.SetHelpTemplate(s string) -``` - -The latter two will also apply to any children commands. - -## Usage Message - -When the user provides an invalid flag or invalid command, Cobra responds by -showing the user the 'usage'. - -### Example -You may recognize this from the help above. That's because the default help -embeds the usage as part of its output. - - $ cobra-cli --invalid - Error: unknown flag: --invalid - Usage: - cobra-cli [command] - - Available Commands: - add Add a command to a Cobra Application - completion Generate the autocompletion script for the specified shell - help Help about any command - init Initialize a Cobra Application - - Flags: - -a, --author string author name for copyright attribution (default "YOUR NAME") - --config string config file (default is $HOME/.cobra.yaml) - -h, --help help for cobra-cli - -l, --license string name of license for the project - --viper use Viper for configuration - - Use "cobra [command] --help" for more information about a command. - -### Defining your own usage -You can provide your own usage function or template for Cobra to use. -Like help, the function and template are overridable through public methods: - -```go -cmd.SetUsageFunc(f func(*Command) error) -cmd.SetUsageTemplate(s string) -``` - -## Version Flag - -Cobra adds a top-level '--version' flag if the Version field is set on the root command. -Running an application with the '--version' flag will print the version to stdout using -the version template. The template can be customized using the -`cmd.SetVersionTemplate(s string)` function. - -## PreRun and PostRun Hooks - -It is possible to run functions before or after the main `Run` function of your command. The `PersistentPreRun` and `PreRun` functions will be executed before `Run`. `PersistentPostRun` and `PostRun` will be executed after `Run`. The `Persistent*Run` functions will be inherited by children if they do not declare their own. These functions are run in the following order: - -- `PersistentPreRun` -- `PreRun` -- `Run` -- `PostRun` -- `PersistentPostRun` - -An example of two commands which use all of these features is below. When the subcommand is executed, it will run the root command's `PersistentPreRun` but not the root command's `PersistentPostRun`: - -```go -package main - -import ( - "fmt" - - "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.Println() - rootCmd.SetArgs([]string{"sub", "arg1", "arg2"}) - rootCmd.Execute() -} -``` - -Output: -``` -Inside rootCmd PersistentPreRun with args: [] -Inside rootCmd PreRun with args: [] -Inside rootCmd Run with args: [] -Inside rootCmd PostRun with args: [] -Inside rootCmd PersistentPostRun with args: [] - -Inside rootCmd PersistentPreRun with args: [arg1 arg2] -Inside subCmd PreRun with args: [arg1 arg2] -Inside subCmd Run with args: [arg1 arg2] -Inside subCmd PostRun with args: [arg1 arg2] -Inside subCmd PersistentPostRun with args: [arg1 arg2] -``` - -## Suggestions when "unknown command" happens - -Cobra will print automatic suggestions when "unknown command" errors happen. This allows Cobra to behave similarly to the `git` command when a typo happens. For example: - -``` -$ hugo srever -Error: unknown command "srever" for "hugo" - -Did you mean this? - server - -Run 'hugo --help' for usage. -``` - -Suggestions are automatically generated based on existing subcommands and use an implementation of [Levenshtein distance](https://en.wikipedia.org/wiki/Levenshtein_distance). Every registered command that matches a minimum distance of 2 (ignoring case) will be displayed as a suggestion. - -If you need to disable suggestions or tweak the string distance in your command, use: - -```go -command.DisableSuggestions = true -``` - -or - -```go -command.SuggestionsMinimumDistance = 1 -``` - -You can also explicitly set names for which a given command will be suggested using the `SuggestFor` attribute. This allows suggestions for strings that are not close in terms of string distance, but make sense in your set of commands but for which -you don't want aliases. Example: - -``` -$ kubectl remove -Error: unknown command "remove" for "kubectl" - -Did you mean this? - delete - -Run 'kubectl help' for usage. -``` - -## Generating documentation for your command - -Cobra can generate documentation based on subcommands, flags, etc. Read more about it in the [docs generation documentation](doc/README.md). - -## Generating shell completions - -Cobra can generate a shell-completion file for the following shells: bash, zsh, fish, PowerShell. If you add more information to your commands, these completions can be amazingly powerful and flexible. Read more about it in [Shell Completions](shell_completions.md). - -## Providing Active Help - -Cobra makes use of the shell-completion system to define a framework allowing you to provide Active Help to your users. Active Help are messages (hints, warnings, etc) printed as the program is being used. Read more about it in [Active Help](active_help.md). |