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diff --git a/vendor/github.com/spf13/cobra/README.md b/vendor/github.com/spf13/cobra/README.md index da9aa881e..d8b5c96c8 100644 --- a/vendor/github.com/spf13/cobra/README.md +++ b/vendor/github.com/spf13/cobra/README.md @@ -19,13 +19,33 @@ Many of the most widely used Go projects are built using Cobra including: * [GiantSwarm's swarm](https://github.com/giantswarm/cli) * [Nanobox](https://github.com/nanobox-io/nanobox)/[Nanopack](https://github.com/nanopack) * [rclone](http://rclone.org/) - +* [nehm](https://github.com/bogem/nehm) [](https://travis-ci.org/spf13/cobra) [](https://circleci.com/gh/spf13/cobra) [](https://godoc.org/github.com/spf13/cobra) - +# Table of Contents + +- [Overview](#overview) +- [Concepts](#concepts) + * [Commands](#commands) + * [Flags](#flags) +- [Installing](#installing) +- [Getting Started](#getting-started) + * [Using the Cobra Generator](#using-the-cobra-generator) + * [Using the Cobra Library](#using-the-cobra-library) + * [Working with Flags](#working-with-flags) + * [Positional and Custom Arguments](#positional-and-custom-arguments) + * [Example](#example) + * [Help Command](#help-command) + * [Usage Message](#usage-message) + * [PreRun and PostRun Hooks](#prerun-and-postrun-hooks) + * [Suggestions when "unknown command" happens](#suggestions-when-unknown-command-happens) + * [Generating documentation for your command](#generating-documentation-for-your-command) + * [Generating bash completions](#generating-bash-completions) +- [Contributing](#contributing) +- [License](#license) # Overview @@ -43,7 +63,6 @@ Cobra provides: * Easy generation of applications & commands with `cobra init appname` & `cobra add cmdname` * Intelligent suggestions (`app srver`... did you mean `app server`?) * Automatic help generation for commands and flags -* Automatic detailed help for `app help [command]` * Automatic help flag recognition of `-h`, `--help`, etc. * Automatically generated bash autocomplete for your application * Automatically generated man pages for your application @@ -51,16 +70,6 @@ Cobra provides: * The flexibility to define your own help, usage, etc. * Optional tight integration with [viper](http://github.com/spf13/viper) for 12-factor apps -Cobra has an exceptionally clean interface and simple design without needless -constructors or initialization methods. - -Applications built with Cobra commands are designed to be as user-friendly as -possible. Flags can be placed before or after the command (as long as a -confusing space isn’t provided). Both short and long flags can be used. A -command need not even be fully typed. Help is automatically generated and -available for the application or for a specific command using either the help -command or the `--help` flag. - # Concepts Cobra is built on a structure of commands, arguments & flags. @@ -93,20 +102,11 @@ have children commands and optionally run an action. In the example above, 'server' is the command. -A Command has the following structure: - -```go -type Command struct { - Use string // The one-line usage message. - Short string // The short description shown in the 'help' output. - Long string // The long message shown in the 'help <this-command>' output. - Run func(cmd *Command, args []string) // Run runs the command. -} -``` +[More about cobra.Command](https://godoc.org/github.com/spf13/cobra#Command) ## Flags -A Flag is a way to modify the behavior of a command. Cobra supports +A flag is a way to modify the behavior of a command. Cobra supports fully POSIX-compliant flags as well as the Go [flag package](https://golang.org/pkg/flag/). A Cobra command can define flags that persist through to children commands and flags that are only available to that command. @@ -170,106 +170,14 @@ func main() { Cobra provides 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. -In order to use the cobra command, compile it using the following command: +[Here](https://github.com/spf13/cobra/blob/master/cobra/README.md) you can find more information about it. - go get github.com/spf13/cobra/cobra - -This will create the cobra executable under your `$GOPATH/bin` directory. - -### cobra init - -The `cobra init [yourApp]` command will create your initial application code -for you. It is a very powerful application that will populate your program with -the right structure so you can immediately enjoy all the benefits of Cobra. It -will also automatically apply the license you specify to your application. - -Cobra init is pretty smart. You can provide it a full path, or simply a path -similar to what is expected in the import. - -``` -cobra init github.com/spf13/newAppName -``` - -### cobra add - -Once an application is initialized Cobra can create additional commands for you. -Let's say you created an app and you wanted the following commands for it: - -* app serve -* app config -* app config create - -In your project directory (where your main.go file is) you would run the following: - -``` -cobra add serve -cobra add config -cobra add create -p 'configCmd' -``` - -*Note: Use camelCase (not snake_case/snake-case) for command names. -Otherwise, you will encounter errors. -For example, `cobra add add-user` is incorrect, but `cobra add addUser` is valid.* - -Once you have run these three commands you would have an app structure similar to -the following: - -``` - ▾ app/ - ▾ cmd/ - serve.go - config.go - create.go - main.go -``` - -At this point you can run `go run main.go` and it would run your app. `go run -main.go serve`, `go run main.go config`, `go run main.go config create` along -with `go run main.go help serve`, etc. would all work. - -Obviously you haven't added your own code to these yet. The commands are ready -for you to give them their tasks. Have fun! - -### Configuring the cobra generator - -The Cobra generator will be easier to use if you provide a simple configuration -file which will help you eliminate providing a bunch of repeated information in -flags over and over. - -An example ~/.cobra.yaml file: - -```yaml -author: Steve Francia <spf@spf13.com> -license: MIT -``` - -You can specify no license by setting `license` to `none` or you can specify -a custom license: - -```yaml -license: - header: This file is part of {{ .appName }}. - text: | - {{ .copyright }} - - This is my license. There are many like it, but this one is mine. - My license is my best friend. It is my life. I must master it as I must - master my life. -``` - -You can also use built-in licenses. For example, **GPLv2**, **GPLv3**, **LGPL**, -**AGPL**, **MIT**, **2-Clause BSD** or **3-Clause BSD**. - -## Manually implementing Cobra +## 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 the root command - -The root command represents your binary itself. - -#### Manually create rootCmd +### Create rootCmd Cobra doesn't require any special constructors. Simply create your commands. @@ -316,10 +224,6 @@ func init() { viper.SetDefault("license", "apache") } -func Execute() { - RootCmd.Execute() -} - func initConfig() { // Don't forget to read config either from cfgFile or from home directory! if cfgFile != "" { @@ -400,17 +304,6 @@ var versionCmd = &cobra.Command{ } ``` -### Attach command to its parent - - -If you notice in the above example we attach the command to its parent. In -this case the parent is the rootCmd. In this example we are attaching it to the -root, but commands can be attached at any level. - -```go -RootCmd.AddCommand(versionCmd) -``` - ## Working with Flags Flags provide modifiers to control how the action command operates. @@ -446,6 +339,19 @@ A flag can also be assigned locally which will only apply to that specific comma RootCmd.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, 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): @@ -569,7 +475,7 @@ a count and a string.`, For a more complete example of a larger application, please checkout [Hugo](http://gohugo.io/). -## The Help Command +## 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 @@ -582,60 +488,28 @@ create' is called. Every command will automatically have the '--help' flag adde The following output is automatically generated by Cobra. Nothing beyond the command and flag definitions are needed. - > hugo help + $ cobra help - hugo is the main command, used to build your Hugo site. - - Hugo is a Fast and Flexible Static Site Generator - built with love by spf13 and friends in Go. - - Complete documentation is available at http://gohugo.io/. + 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: - hugo [flags] - hugo [command] + cobra [command] Available Commands: - server Hugo runs its own webserver to render the files - version Print the version number of Hugo - config Print the site configuration - check Check content in the source directory - benchmark Benchmark hugo by building a site a number of times. - convert Convert your content to different formats - new Create new content for your site - list Listing out various types of content - undraft Undraft changes the content's draft status from 'True' to 'False' - genautocomplete Generate shell autocompletion script for Hugo - gendoc Generate Markdown documentation for the Hugo CLI. - genman Generate man page for Hugo - import Import your site from others. + add Add a command to a Cobra Application + help Help about any command + init Initialize a Cobra Application Flags: - -b, --baseURL="": hostname (and path) to the root, e.g. http://spf13.com/ - -D, --buildDrafts[=false]: include content marked as draft - -F, --buildFuture[=false]: include content with publishdate in the future - --cacheDir="": filesystem path to cache directory. Defaults: $TMPDIR/hugo_cache/ - --canonifyURLs[=false]: if true, all relative URLs will be canonicalized using baseURL - --config="": config file (default is path/config.yaml|json|toml) - -d, --destination="": filesystem path to write files to - --disableRSS[=false]: Do not build RSS files - --disableSitemap[=false]: Do not build Sitemap file - --editor="": edit new content with this editor, if provided - --ignoreCache[=false]: Ignores the cache directory for reading but still writes to it - --log[=false]: Enable Logging - --logFile="": Log File path (if set, logging enabled automatically) - --noTimes[=false]: Don't sync modification time of files - --pluralizeListTitles[=true]: Pluralize titles in lists using inflect - --preserveTaxonomyNames[=false]: Preserve taxonomy names as written ("Gérard Depardieu" vs "gerard-depardieu") - -s, --source="": filesystem path to read files relative from - --stepAnalysis[=false]: display memory and timing of different steps of the program - -t, --theme="": theme to use (located in /themes/THEMENAME/) - --uglyURLs[=false]: if true, use /filename.html instead of /filename/ - -v, --verbose[=false]: verbose output - --verboseLog[=false]: verbose logging - -w, --watch[=false]: watch filesystem for changes and recreate as needed - - Use "hugo [command] --help" for more information about a command. + -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 + -l, --license string name of license for the project + --viper use Viper for configuration (default true) + + Use "cobra [command] --help" for more information about a command. Help is just a command like any other. There is no special logic or behavior @@ -643,36 +517,18 @@ around it. In fact, you can provide your own if you want. ### Defining your own help -You can provide your own Help command or your own template for the default command to use. - -The default help command is +You can provide your own Help command or your own template for the default command to use +with followind functions: ```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. - Simply type ` + c.Name() + ` help [path to command] for full details.`, - Run: c.HelpFunc(), - } - } - c.AddCommand(c.helpCommand) -} -``` - -You can provide your own command, function or template through the following methods: - -```go -command.SetHelpCommand(cmd *Command) -command.SetHelpFunc(f func(*Command, []string)) -command.SetHelpTemplate(s string) +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 +## Usage Message When the user provides an invalid flag or invalid command, Cobra responds by showing the user the 'usage'. @@ -681,71 +537,35 @@ showing the user the 'usage'. You may recognize this from the help above. That's because the default help embeds the usage as part of its output. + $ cobra --invalid + Error: unknown flag: --invalid Usage: - hugo [flags] - hugo [command] + cobra [command] Available Commands: - server Hugo runs its own webserver to render the files - version Print the version number of Hugo - config Print the site configuration - check Check content in the source directory - benchmark Benchmark hugo by building a site a number of times. - convert Convert your content to different formats - new Create new content for your site - list Listing out various types of content - undraft Undraft changes the content's draft status from 'True' to 'False' - genautocomplete Generate shell autocompletion script for Hugo - gendoc Generate Markdown documentation for the Hugo CLI. - genman Generate man page for Hugo - import Import your site from others. + add Add a command to a Cobra Application + help Help about any command + init Initialize a Cobra Application Flags: - -b, --baseURL="": hostname (and path) to the root, e.g. http://spf13.com/ - -D, --buildDrafts[=false]: include content marked as draft - -F, --buildFuture[=false]: include content with publishdate in the future - --cacheDir="": filesystem path to cache directory. Defaults: $TMPDIR/hugo_cache/ - --canonifyURLs[=false]: if true, all relative URLs will be canonicalized using baseURL - --config="": config file (default is path/config.yaml|json|toml) - -d, --destination="": filesystem path to write files to - --disableRSS[=false]: Do not build RSS files - --disableSitemap[=false]: Do not build Sitemap file - --editor="": edit new content with this editor, if provided - --ignoreCache[=false]: Ignores the cache directory for reading but still writes to it - --log[=false]: Enable Logging - --logFile="": Log File path (if set, logging enabled automatically) - --noTimes[=false]: Don't sync modification time of files - --pluralizeListTitles[=true]: Pluralize titles in lists using inflect - --preserveTaxonomyNames[=false]: Preserve taxonomy names as written ("Gérard Depardieu" vs "gerard-depardieu") - -s, --source="": filesystem path to read files relative from - --stepAnalysis[=false]: display memory and timing of different steps of the program - -t, --theme="": theme to use (located in /themes/THEMENAME/) - --uglyURLs[=false]: if true, use /filename.html instead of /filename/ - -v, --verbose[=false]: verbose output - --verboseLog[=false]: verbose logging - -w, --watch[=false]: watch filesystem for changes and recreate as needed + -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 + -l, --license string name of license for the project + --viper use Viper for configuration (default true) + + 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. - -The default usage function is: - -```go -return func(c *Command) error { - err := tmpl(c.Out(), c.UsageTemplate(), c) - return err -} -``` - Like help, the function and template are overridable through public methods: ```go -command.SetUsageFunc(f func(*Command) error) - -command.SetUsageTemplate(s string) +cmd.SetUsageFunc(f func(*Command) error) +cmd.SetUsageTemplate(s string) ``` -## PreRun or PostRun Hooks +## 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: @@ -815,51 +635,19 @@ func main() { } ``` +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: [] -## Alternative Error Handling - -Cobra also has functions where the return signature is an error. This allows for errors to bubble up to the top, -providing a way to handle the errors in one location. The current list of functions that return an error is: - -* PersistentPreRunE -* PreRunE -* RunE -* PostRunE -* PersistentPostRunE - -If you would like to silence the default `error` and `usage` output in favor of your own, you can set `SilenceUsage` -and `SilenceErrors` to `true` on the command. A child command respects these flags if they are set on the parent -command. - -**Example Usage using RunE:** - -```go -package main - -import ( - "errors" - "log" - - "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) - } -} +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 @@ -902,41 +690,28 @@ Did you mean this? Run 'kubectl help' for usage. ``` -## Generating Markdown-formatted documentation for your command +## Generating documentation for your command -Cobra can generate a Markdown-formatted document based on the subcommands, flags, etc. A simple example of how to do this for your command can be found in [Markdown Docs](doc/md_docs.md). +Cobra can generate documentation based on subcommands, flags, etc. in the following formats: -## Generating man pages for your command +- [Markdown](doc/md_docs.md) +- [ReStructured Text](doc/rest_docs.md) +- [Man Page](doc/man_docs.md) -Cobra can generate a man page based on the subcommands, flags, etc. A simple example of how to do this for your command can be found in [Man Docs](doc/man_docs.md). - -## Generating bash completions for your command +## Generating bash completions 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). - -## Extensions - -Libraries for extending Cobra: - -* [cmdns](https://github.com/gosuri/cmdns): Enables name spacing a command's immediate children. It provides an alternative way to structure subcommands, similar to `heroku apps:create` and `ovrclk clusters:launch`. - -## Contributing +# Contributing 1. Fork it -2. Create your feature branch (`git checkout -b my-new-feature`) -3. Commit your changes (`git commit -am 'Add some feature'`) -4. Push to the branch (`git push origin my-new-feature`) -5. Create new Pull Request - -## Contributors - -Names in no particular order: - -* [spf13](https://github.com/spf13), -[eparis](https://github.com/eparis), -[bep](https://github.com/bep), and many more! - -## License +2. Download your fork to your PC (`git clone https://github.com/your_username/cobra && cd cobra`) +3. Create your feature branch (`git checkout -b my-new-feature`) +4. Make changes and add them (`git add .`) +5. Commit your changes (`git commit -m 'Add some feature'`) +6. Push to the branch (`git push origin my-new-feature`) +7. Create new pull request + +# License Cobra is released under the Apache 2.0 license. See [LICENSE.txt](https://github.com/spf13/cobra/blob/master/LICENSE.txt) |