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diff --git a/vendor/github.com/urfave/cli/README.md b/vendor/github.com/urfave/cli/README.md deleted file mode 100644 index f2baef4f0..000000000 --- a/vendor/github.com/urfave/cli/README.md +++ /dev/null @@ -1,1526 +0,0 @@ -cli -=== - -[![Build Status](https://travis-ci.org/urfave/cli.svg?branch=master)](https://travis-ci.org/urfave/cli) -[![Windows Build Status](https://ci.appveyor.com/api/projects/status/rtgk5xufi932pb2v?svg=true)](https://ci.appveyor.com/project/urfave/cli) -[![GoDoc](https://godoc.org/github.com/urfave/cli?status.svg)](https://godoc.org/github.com/urfave/cli) -[![codebeat](https://codebeat.co/badges/0a8f30aa-f975-404b-b878-5fab3ae1cc5f)](https://codebeat.co/projects/github-com-urfave-cli) -[![Go Report Card](https://goreportcard.com/badge/urfave/cli)](https://goreportcard.com/report/urfave/cli) -[![top level coverage](https://gocover.io/_badge/github.com/urfave/cli?0 "top level coverage")](http://gocover.io/github.com/urfave/cli) / -[![altsrc coverage](https://gocover.io/_badge/github.com/urfave/cli/altsrc?0 "altsrc coverage")](http://gocover.io/github.com/urfave/cli/altsrc) - -This is the library formerly known as `github.com/codegangsta/cli` -- Github -will automatically redirect requests to this repository, but we recommend -updating your references for clarity. - -cli is a simple, fast, and fun package for building command line apps in Go. The -goal is to enable developers to write fast and distributable command line -applications in an expressive way. - -<!-- toc --> - -- [Overview](#overview) -- [Installation](#installation) - * [Supported platforms](#supported-platforms) - * [Using the `v2` branch](#using-the-v2-branch) - * [Pinning to the `v1` releases](#pinning-to-the-v1-releases) -- [Getting Started](#getting-started) -- [Examples](#examples) - * [Arguments](#arguments) - * [Flags](#flags) - + [Placeholder Values](#placeholder-values) - + [Alternate Names](#alternate-names) - + [Ordering](#ordering) - + [Values from the Environment](#values-from-the-environment) - + [Values from files](#values-from-files) - + [Values from alternate input sources (YAML, TOML, and others)](#values-from-alternate-input-sources-yaml-toml-and-others) - + [Precedence](#precedence) - * [Subcommands](#subcommands) - * [Subcommands categories](#subcommands-categories) - * [Exit code](#exit-code) - * [Bash Completion](#bash-completion) - + [Enabling](#enabling) - + [Distribution](#distribution) - + [Customization](#customization) - * [Generated Help Text](#generated-help-text) - + [Customization](#customization-1) - * [Version Flag](#version-flag) - + [Customization](#customization-2) - + [Full API Example](#full-api-example) - * [Combining short Bool options](#combining-short-bool-options) -- [Contribution Guidelines](#contribution-guidelines) - -<!-- tocstop --> - -## Overview - -Command line apps are usually so tiny that there is absolutely no reason why -your code should *not* be self-documenting. Things like generating help text and -parsing command flags/options should not hinder productivity when writing a -command line app. - -**This is where cli comes into play.** cli makes command line programming fun, -organized, and expressive! - -## Installation - -Make sure you have a working Go environment. Go version 1.2+ is supported. [See -the install instructions for Go](http://golang.org/doc/install.html). - -To install cli, simply run: -``` -$ go get github.com/urfave/cli -``` - -Make sure your `PATH` includes the `$GOPATH/bin` directory so your commands can -be easily used: -``` -export PATH=$PATH:$GOPATH/bin -``` - -### Supported platforms - -cli is tested against multiple versions of Go on Linux, and against the latest -released version of Go on OS X and Windows. For full details, see -[`./.travis.yml`](./.travis.yml) and [`./appveyor.yml`](./appveyor.yml). - -### Using the `v2` branch - -**Warning**: The `v2` branch is currently unreleased and considered unstable. - -There is currently a long-lived branch named `v2` that is intended to land as -the new `master` branch once development there has settled down. The current -`master` branch (mirrored as `v1`) is being manually merged into `v2` on -an irregular human-based schedule, but generally if one wants to "upgrade" to -`v2` *now* and accept the volatility (read: "awesomeness") that comes along with -that, please use whatever version pinning of your preference, such as via -`gopkg.in`: - -``` -$ go get gopkg.in/urfave/cli.v2 -``` - -``` go -... -import ( - "gopkg.in/urfave/cli.v2" // imports as package "cli" -) -... -``` - -### Pinning to the `v1` releases - -Similarly to the section above describing use of the `v2` branch, if one wants -to avoid any unexpected compatibility pains once `v2` becomes `master`, then -pinning to `v1` is an acceptable option, e.g.: - -``` -$ go get gopkg.in/urfave/cli.v1 -``` - -``` go -... -import ( - "gopkg.in/urfave/cli.v1" // imports as package "cli" -) -... -``` - -This will pull the latest tagged `v1` release (e.g. `v1.18.1` at the time of writing). - -## Getting Started - -One of the philosophies behind cli is that an API should be playful and full of -discovery. So a cli app can be as little as one line of code in `main()`. - -<!-- { - "args": ["--help"], - "output": "A new cli application" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - err := cli.NewApp().Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -This app will run and show help text, but is not very useful. Let's give an -action to execute and some help documentation: - -<!-- { - "output": "boom! I say!" -} --> -``` go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - app.Name = "boom" - app.Usage = "make an explosive entrance" - app.Action = func(c *cli.Context) error { - fmt.Println("boom! I say!") - return nil - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Running this already gives you a ton of functionality, plus support for things -like subcommands and flags, which are covered below. - -## Examples - -Being a programmer can be a lonely job. Thankfully by the power of automation -that is not the case! Let's create a greeter app to fend off our demons of -loneliness! - -Start by creating a directory named `greet`, and within it, add a file, -`greet.go` with the following code in it: - -<!-- { - "output": "Hello friend!" -} --> -``` go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - app.Name = "greet" - app.Usage = "fight the loneliness!" - app.Action = func(c *cli.Context) error { - fmt.Println("Hello friend!") - return nil - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Install our command to the `$GOPATH/bin` directory: - -``` -$ go install -``` - -Finally run our new command: - -``` -$ greet -Hello friend! -``` - -cli also generates neat help text: - -``` -$ greet help -NAME: - greet - fight the loneliness! - -USAGE: - greet [global options] command [command options] [arguments...] - -VERSION: - 0.0.0 - -COMMANDS: - help, h Shows a list of commands or help for one command - -GLOBAL OPTIONS - --version Shows version information -``` - -### Arguments - -You can lookup arguments by calling the `Args` function on `cli.Context`, e.g.: - -<!-- { - "output": "Hello \"" -} --> -``` go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Action = func(c *cli.Context) error { - fmt.Printf("Hello %q", c.Args().Get(0)) - return nil - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -### Flags - -Setting and querying flags is simple. - -<!-- { - "output": "Hello Nefertiti" -} --> -``` go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "lang", - Value: "english", - Usage: "language for the greeting", - }, - } - - app.Action = func(c *cli.Context) error { - name := "Nefertiti" - if c.NArg() > 0 { - name = c.Args().Get(0) - } - if c.String("lang") == "spanish" { - fmt.Println("Hola", name) - } else { - fmt.Println("Hello", name) - } - return nil - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -You can also set a destination variable for a flag, to which the content will be -scanned. - -<!-- { - "output": "Hello someone" -} --> -``` go -package main - -import ( - "log" - "os" - "fmt" - - "github.com/urfave/cli" -) - -func main() { - var language string - - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "lang", - Value: "english", - Usage: "language for the greeting", - Destination: &language, - }, - } - - app.Action = func(c *cli.Context) error { - name := "someone" - if c.NArg() > 0 { - name = c.Args()[0] - } - if language == "spanish" { - fmt.Println("Hola", name) - } else { - fmt.Println("Hello", name) - } - return nil - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -See full list of flags at http://godoc.org/github.com/urfave/cli - -#### Placeholder Values - -Sometimes it's useful to specify a flag's value within the usage string itself. -Such placeholders are indicated with back quotes. - -For example this: - -<!-- { - "args": ["--help"], - "output": "--config FILE, -c FILE" -} --> -```go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag{ - cli.StringFlag{ - Name: "config, c", - Usage: "Load configuration from `FILE`", - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Will result in help output like: - -``` ---config FILE, -c FILE Load configuration from FILE -``` - -Note that only the first placeholder is used. Subsequent back-quoted words will -be left as-is. - -#### Alternate Names - -You can set alternate (or short) names for flags by providing a comma-delimited -list for the `Name`. e.g. - -<!-- { - "args": ["--help"], - "output": "--lang value, -l value.*language for the greeting.*default: \"english\"" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "lang, l", - Value: "english", - Usage: "language for the greeting", - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -That flag can then be set with `--lang spanish` or `-l spanish`. Note that -giving two different forms of the same flag in the same command invocation is an -error. - -#### Ordering - -Flags for the application and commands are shown in the order they are defined. -However, it's possible to sort them from outside this library by using `FlagsByName` -or `CommandsByName` with `sort`. - -For example this: - -<!-- { - "args": ["--help"], - "output": "add a task to the list\n.*complete a task on the list\n.*\n\n.*\n.*Load configuration from FILE\n.*Language for the greeting.*" -} --> -``` go -package main - -import ( - "log" - "os" - "sort" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "lang, l", - Value: "english", - Usage: "Language for the greeting", - }, - cli.StringFlag{ - Name: "config, c", - Usage: "Load configuration from `FILE`", - }, - } - - app.Commands = []cli.Command{ - { - Name: "complete", - Aliases: []string{"c"}, - Usage: "complete a task on the list", - Action: func(c *cli.Context) error { - return nil - }, - }, - { - Name: "add", - Aliases: []string{"a"}, - Usage: "add a task to the list", - Action: func(c *cli.Context) error { - return nil - }, - }, - } - - sort.Sort(cli.FlagsByName(app.Flags)) - sort.Sort(cli.CommandsByName(app.Commands)) - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Will result in help output like: - -``` ---config FILE, -c FILE Load configuration from FILE ---lang value, -l value Language for the greeting (default: "english") -``` - -#### Values from the Environment - -You can also have the default value set from the environment via `EnvVar`. e.g. - -<!-- { - "args": ["--help"], - "output": "language for the greeting.*APP_LANG" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "lang, l", - Value: "english", - Usage: "language for the greeting", - EnvVar: "APP_LANG", - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -The `EnvVar` may also be given as a comma-delimited "cascade", where the first -environment variable that resolves is used as the default. - -<!-- { - "args": ["--help"], - "output": "language for the greeting.*LEGACY_COMPAT_LANG.*APP_LANG.*LANG" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "lang, l", - Value: "english", - Usage: "language for the greeting", - EnvVar: "LEGACY_COMPAT_LANG,APP_LANG,LANG", - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -#### Values from files - -You can also have the default value set from file via `FilePath`. e.g. - -<!-- { - "args": ["--help"], - "output": "password for the mysql database" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Flags = []cli.Flag { - cli.StringFlag{ - Name: "password, p", - Usage: "password for the mysql database", - FilePath: "/etc/mysql/password", - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Note that default values set from file (e.g. `FilePath`) take precedence over -default values set from the enviornment (e.g. `EnvVar`). - -#### Values from alternate input sources (YAML, TOML, and others) - -There is a separate package altsrc that adds support for getting flag values -from other file input sources. - -Currently supported input source formats: -* YAML -* TOML - -In order to get values for a flag from an alternate input source the following -code would be added to wrap an existing cli.Flag like below: - -``` go - altsrc.NewIntFlag(cli.IntFlag{Name: "test"}) -``` - -Initialization must also occur for these flags. Below is an example initializing -getting data from a yaml file below. - -``` go - command.Before = altsrc.InitInputSourceWithContext(command.Flags, NewYamlSourceFromFlagFunc("load")) -``` - -The code above will use the "load" string as a flag name to get the file name of -a yaml file from the cli.Context. It will then use that file name to initialize -the yaml input source for any flags that are defined on that command. As a note -the "load" flag used would also have to be defined on the command flags in order -for this code snipped to work. - -Currently only YAML and JSON files are supported but developers can add support -for other input sources by implementing the altsrc.InputSourceContext for their -given sources. - -Here is a more complete sample of a command using YAML support: - -<!-- { - "args": ["test-cmd", "--help"], - "output": "--test value.*default: 0" -} --> -``` go -package notmain - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" - "github.com/urfave/cli/altsrc" -) - -func main() { - app := cli.NewApp() - - flags := []cli.Flag{ - altsrc.NewIntFlag(cli.IntFlag{Name: "test"}), - cli.StringFlag{Name: "load"}, - } - - app.Action = func(c *cli.Context) error { - fmt.Println("yaml ist rad") - return nil - } - - app.Before = altsrc.InitInputSourceWithContext(flags, altsrc.NewYamlSourceFromFlagFunc("load")) - app.Flags = flags - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -#### Precedence - -The precedence for flag value sources is as follows (highest to lowest): - -0. Command line flag value from user -0. Environment variable (if specified) -0. Configuration file (if specified) -0. Default defined on the flag - -### Subcommands - -Subcommands can be defined for a more git-like command line app. - -<!-- { - "args": ["template", "add"], - "output": "new task template: .+" -} --> -```go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Commands = []cli.Command{ - { - Name: "add", - Aliases: []string{"a"}, - Usage: "add a task to the list", - Action: func(c *cli.Context) error { - fmt.Println("added task: ", c.Args().First()) - return nil - }, - }, - { - Name: "complete", - Aliases: []string{"c"}, - Usage: "complete a task on the list", - Action: func(c *cli.Context) error { - fmt.Println("completed task: ", c.Args().First()) - return nil - }, - }, - { - Name: "template", - Aliases: []string{"t"}, - Usage: "options for task templates", - Subcommands: []cli.Command{ - { - Name: "add", - Usage: "add a new template", - Action: func(c *cli.Context) error { - fmt.Println("new task template: ", c.Args().First()) - return nil - }, - }, - { - Name: "remove", - Usage: "remove an existing template", - Action: func(c *cli.Context) error { - fmt.Println("removed task template: ", c.Args().First()) - return nil - }, - }, - }, - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -### Subcommands categories - -For additional organization in apps that have many subcommands, you can -associate a category for each command to group them together in the help -output. - -E.g. - -```go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - - app.Commands = []cli.Command{ - { - Name: "noop", - }, - { - Name: "add", - Category: "Template actions", - }, - { - Name: "remove", - Category: "Template actions", - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Will include: - -``` -COMMANDS: - noop - - Template actions: - add - remove -``` - -### Exit code - -Calling `App.Run` will not automatically call `os.Exit`, which means that by -default the exit code will "fall through" to being `0`. An explicit exit code -may be set by returning a non-nil error that fulfills `cli.ExitCoder`, *or* a -`cli.MultiError` that includes an error that fulfills `cli.ExitCoder`, e.g.: - -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - app := cli.NewApp() - app.Flags = []cli.Flag{ - cli.BoolTFlag{ - Name: "ginger-crouton", - Usage: "is it in the soup?", - }, - } - app.Action = func(ctx *cli.Context) error { - if !ctx.Bool("ginger-crouton") { - return cli.NewExitError("it is not in the soup", 86) - } - return nil - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -### Bash Completion - -You can enable completion commands by setting the `EnableBashCompletion` -flag on the `App` object. By default, this setting will only auto-complete to -show an app's subcommands, but you can write your own completion methods for -the App or its subcommands. - -<!-- { - "args": ["complete", "--generate-bash-completion"], - "output": "laundry" -} --> -``` go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - tasks := []string{"cook", "clean", "laundry", "eat", "sleep", "code"} - - app := cli.NewApp() - app.EnableBashCompletion = true - app.Commands = []cli.Command{ - { - Name: "complete", - Aliases: []string{"c"}, - Usage: "complete a task on the list", - Action: func(c *cli.Context) error { - fmt.Println("completed task: ", c.Args().First()) - return nil - }, - BashComplete: func(c *cli.Context) { - // This will complete if no args are passed - if c.NArg() > 0 { - return - } - for _, t := range tasks { - fmt.Println(t) - } - }, - }, - } - - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -#### Enabling - -Source the `autocomplete/bash_autocomplete` file in your `.bashrc` file while -setting the `PROG` variable to the name of your program: - -`PROG=myprogram source /.../cli/autocomplete/bash_autocomplete` - -#### Distribution - -Copy `autocomplete/bash_autocomplete` into `/etc/bash_completion.d/` and rename -it to the name of the program you wish to add autocomplete support for (or -automatically install it there if you are distributing a package). Don't forget -to source the file to make it active in the current shell. - -``` -sudo cp src/bash_autocomplete /etc/bash_completion.d/<myprogram> -source /etc/bash_completion.d/<myprogram> -``` - -Alternatively, you can just document that users should source the generic -`autocomplete/bash_autocomplete` in their bash configuration with `$PROG` set -to the name of their program (as above). - -#### Customization - -The default bash completion flag (`--generate-bash-completion`) is defined as -`cli.BashCompletionFlag`, and may be redefined if desired, e.g.: - -<!-- { - "args": ["--compgen"], - "output": "wat\nhelp\nh" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - cli.BashCompletionFlag = cli.BoolFlag{ - Name: "compgen", - Hidden: true, - } - - app := cli.NewApp() - app.EnableBashCompletion = true - app.Commands = []cli.Command{ - { - Name: "wat", - }, - } - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -### Generated Help Text - -The default help flag (`-h/--help`) is defined as `cli.HelpFlag` and is checked -by the cli internals in order to print generated help text for the app, command, -or subcommand, and break execution. - -#### Customization - -All of the help text generation may be customized, and at multiple levels. The -templates are exposed as variables `AppHelpTemplate`, `CommandHelpTemplate`, and -`SubcommandHelpTemplate` which may be reassigned or augmented, and full override -is possible by assigning a compatible func to the `cli.HelpPrinter` variable, -e.g.: - -<!-- { - "output": "Ha HA. I pwnd the help!!1" -} --> -``` go -package main - -import ( - "fmt" - "log" - "io" - "os" - - "github.com/urfave/cli" -) - -func main() { - // EXAMPLE: Append to an existing template - cli.AppHelpTemplate = fmt.Sprintf(`%s - -WEBSITE: http://awesometown.example.com - -SUPPORT: support@awesometown.example.com - -`, cli.AppHelpTemplate) - - // EXAMPLE: Override a template - cli.AppHelpTemplate = `NAME: - {{.Name}} - {{.Usage}} -USAGE: - {{.HelpName}} {{if .VisibleFlags}}[global options]{{end}}{{if .Commands}} command [command options]{{end}} {{if .ArgsUsage}}{{.ArgsUsage}}{{else}}[arguments...]{{end}} - {{if len .Authors}} -AUTHOR: - {{range .Authors}}{{ . }}{{end}} - {{end}}{{if .Commands}} -COMMANDS: -{{range .Commands}}{{if not .HideHelp}} {{join .Names ", "}}{{ "\t"}}{{.Usage}}{{ "\n" }}{{end}}{{end}}{{end}}{{if .VisibleFlags}} -GLOBAL OPTIONS: - {{range .VisibleFlags}}{{.}} - {{end}}{{end}}{{if .Copyright }} -COPYRIGHT: - {{.Copyright}} - {{end}}{{if .Version}} -VERSION: - {{.Version}} - {{end}} -` - - // EXAMPLE: Replace the `HelpPrinter` func - cli.HelpPrinter = func(w io.Writer, templ string, data interface{}) { - fmt.Println("Ha HA. I pwnd the help!!1") - } - - err := cli.NewApp().Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -The default flag may be customized to something other than `-h/--help` by -setting `cli.HelpFlag`, e.g.: - -<!-- { - "args": ["--halp"], - "output": "haaaaalp.*HALP" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - cli.HelpFlag = cli.BoolFlag{ - Name: "halp, haaaaalp", - Usage: "HALP", - EnvVar: "SHOW_HALP,HALPPLZ", - } - - err := cli.NewApp().Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -### Version Flag - -The default version flag (`-v/--version`) is defined as `cli.VersionFlag`, which -is checked by the cli internals in order to print the `App.Version` via -`cli.VersionPrinter` and break execution. - -#### Customization - -The default flag may be customized to something other than `-v/--version` by -setting `cli.VersionFlag`, e.g.: - -<!-- { - "args": ["--print-version"], - "output": "partay version 19\\.99\\.0" -} --> -``` go -package main - -import ( - "log" - "os" - - "github.com/urfave/cli" -) - -func main() { - cli.VersionFlag = cli.BoolFlag{ - Name: "print-version, V", - Usage: "print only the version", - } - - app := cli.NewApp() - app.Name = "partay" - app.Version = "19.99.0" - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -Alternatively, the version printer at `cli.VersionPrinter` may be overridden, e.g.: - -<!-- { - "args": ["--version"], - "output": "version=19\\.99\\.0 revision=fafafaf" -} --> -``` go -package main - -import ( - "fmt" - "log" - "os" - - "github.com/urfave/cli" -) - -var ( - Revision = "fafafaf" -) - -func main() { - cli.VersionPrinter = func(c *cli.Context) { - fmt.Printf("version=%s revision=%s\n", c.App.Version, Revision) - } - - app := cli.NewApp() - app.Name = "partay" - app.Version = "19.99.0" - err := app.Run(os.Args) - if err != nil { - log.Fatal(err) - } -} -``` - -#### Full API Example - -**Notice**: This is a contrived (functioning) example meant strictly for API -demonstration purposes. Use of one's imagination is encouraged. - -<!-- { - "output": "made it!\nPhew!" -} --> -``` go -package main - -import ( - "errors" - "flag" - "fmt" - "io" - "io/ioutil" - "os" - "time" - - "github.com/urfave/cli" -) - -func init() { - cli.AppHelpTemplate += "\nCUSTOMIZED: you bet ur muffins\n" - cli.CommandHelpTemplate += "\nYMMV\n" - cli.SubcommandHelpTemplate += "\nor something\n" - - cli.HelpFlag = cli.BoolFlag{Name: "halp"} - cli.BashCompletionFlag = cli.BoolFlag{Name: "compgen", Hidden: true} - cli.VersionFlag = cli.BoolFlag{Name: "print-version, V"} - - cli.HelpPrinter = func(w io.Writer, templ string, data interface{}) { - fmt.Fprintf(w, "best of luck to you\n") - } - cli.VersionPrinter = func(c *cli.Context) { - fmt.Fprintf(c.App.Writer, "version=%s\n", c.App.Version) - } - cli.OsExiter = func(c int) { - fmt.Fprintf(cli.ErrWriter, "refusing to exit %d\n", c) - } - cli.ErrWriter = ioutil.Discard - cli.FlagStringer = func(fl cli.Flag) string { - return fmt.Sprintf("\t\t%s", fl.GetName()) - } -} - -type hexWriter struct{} - -func (w *hexWriter) Write(p []byte) (int, error) { - for _, b := range p { - fmt.Printf("%x", b) - } - fmt.Printf("\n") - - return len(p), nil -} - -type genericType struct{ - s string -} - -func (g *genericType) Set(value string) error { - g.s = value - return nil -} - -func (g *genericType) String() string { - return g.s -} - -func main() { - app := cli.NewApp() - app.Name = "kənˈtrīv" - app.Version = "19.99.0" - app.Compiled = time.Now() - app.Authors = []cli.Author{ - cli.Author{ - Name: "Example Human", - Email: "human@example.com", - }, - } - app.Copyright = "(c) 1999 Serious Enterprise" - app.HelpName = "contrive" - app.Usage = "demonstrate available API" - app.UsageText = "contrive - demonstrating the available API" - app.ArgsUsage = "[args and such]" - app.Commands = []cli.Command{ - cli.Command{ - Name: "doo", - Aliases: []string{"do"}, - Category: "motion", - Usage: "do the doo", - UsageText: "doo - does the dooing", - Description: "no really, there is a lot of dooing to be done", - ArgsUsage: "[arrgh]", - Flags: []cli.Flag{ - cli.BoolFlag{Name: "forever, forevvarr"}, - }, - Subcommands: cli.Commands{ - cli.Command{ - Name: "wop", - Action: wopAction, - }, - }, - SkipFlagParsing: false, - HideHelp: false, - Hidden: false, - HelpName: "doo!", - BashComplete: func(c *cli.Context) { - fmt.Fprintf(c.App.Writer, "--better\n") - }, - Before: func(c *cli.Context) error { - fmt.Fprintf(c.App.Writer, "brace for impact\n") - return nil - }, - After: func(c *cli.Context) error { - fmt.Fprintf(c.App.Writer, "did we lose anyone?\n") - return nil - }, - Action: func(c *cli.Context) error { - c.Command.FullName() - c.Command.HasName("wop") - c.Command.Names() - c.Command.VisibleFlags() - fmt.Fprintf(c.App.Writer, "dodododododoodododddooooododododooo\n") - if c.Bool("forever") { - c.Command.Run(c) - } - return nil - }, - OnUsageError: func(c *cli.Context, err error, isSubcommand bool) error { - fmt.Fprintf(c.App.Writer, "for shame\n") - return err - }, - }, - } - app.Flags = []cli.Flag{ - cli.BoolFlag{Name: "fancy"}, - cli.BoolTFlag{Name: "fancier"}, - cli.DurationFlag{Name: "howlong, H", Value: time.Second * 3}, - cli.Float64Flag{Name: "howmuch"}, - cli.GenericFlag{Name: "wat", Value: &genericType{}}, - cli.Int64Flag{Name: "longdistance"}, - cli.Int64SliceFlag{Name: "intervals"}, - cli.IntFlag{Name: "distance"}, - cli.IntSliceFlag{Name: "times"}, - cli.StringFlag{Name: "dance-move, d"}, - cli.StringSliceFlag{Name: "names, N"}, - cli.UintFlag{Name: "age"}, - cli.Uint64Flag{Name: "bigage"}, - } - app.EnableBashCompletion = true - app.HideHelp = false - app.HideVersion = false - app.BashComplete = func(c *cli.Context) { - fmt.Fprintf(c.App.Writer, "lipstick\nkiss\nme\nlipstick\nringo\n") - } - app.Before = func(c *cli.Context) error { - fmt.Fprintf(c.App.Writer, "HEEEERE GOES\n") - return nil - } - app.After = func(c *cli.Context) error { - fmt.Fprintf(c.App.Writer, "Phew!\n") - return nil - } - app.CommandNotFound = func(c *cli.Context, command string) { - fmt.Fprintf(c.App.Writer, "Thar be no %q here.\n", command) - } - app.OnUsageError = func(c *cli.Context, err error, isSubcommand bool) error { - if isSubcommand { - return err - } - - fmt.Fprintf(c.App.Writer, "WRONG: %#v\n", err) - return nil - } - app.Action = func(c *cli.Context) error { - cli.DefaultAppComplete(c) - cli.HandleExitCoder(errors.New("not an exit coder, though")) - cli.ShowAppHelp(c) - cli.ShowCommandCompletions(c, "nope") - cli.ShowCommandHelp(c, "also-nope") - cli.ShowCompletions(c) - cli.ShowSubcommandHelp(c) - cli.ShowVersion(c) - - categories := c.App.Categories() - categories.AddCommand("sounds", cli.Command{ - Name: "bloop", - }) - - for _, category := range c.App.Categories() { - fmt.Fprintf(c.App.Writer, "%s\n", category.Name) - fmt.Fprintf(c.App.Writer, "%#v\n", category.Commands) - fmt.Fprintf(c.App.Writer, "%#v\n", category.VisibleCommands()) - } - - fmt.Printf("%#v\n", c.App.Command("doo")) - if c.Bool("infinite") { - c.App.Run([]string{"app", "doo", "wop"}) - } - - if c.Bool("forevar") { - c.App.RunAsSubcommand(c) - } - c.App.Setup() - fmt.Printf("%#v\n", c.App.VisibleCategories()) - fmt.Printf("%#v\n", c.App.VisibleCommands()) - fmt.Printf("%#v\n", c.App.VisibleFlags()) - - fmt.Printf("%#v\n", c.Args().First()) - if len(c.Args()) > 0 { - fmt.Printf("%#v\n", c.Args()[1]) - } - fmt.Printf("%#v\n", c.Args().Present()) - fmt.Printf("%#v\n", c.Args().Tail()) - - set := flag.NewFlagSet("contrive", 0) - nc := cli.NewContext(c.App, set, c) - - fmt.Printf("%#v\n", nc.Args()) - fmt.Printf("%#v\n", nc.Bool("nope")) - fmt.Printf("%#v\n", nc.BoolT("nerp")) - fmt.Printf("%#v\n", nc.Duration("howlong")) - fmt.Printf("%#v\n", nc.Float64("hay")) - fmt.Printf("%#v\n", nc.Generic("bloop")) - fmt.Printf("%#v\n", nc.Int64("bonk")) - fmt.Printf("%#v\n", nc.Int64Slice("burnks")) - fmt.Printf("%#v\n", nc.Int("bips")) - fmt.Printf("%#v\n", nc.IntSlice("blups")) - fmt.Printf("%#v\n", nc.String("snurt")) - fmt.Printf("%#v\n", nc.StringSlice("snurkles")) - fmt.Printf("%#v\n", nc.Uint("flub")) - fmt.Printf("%#v\n", nc.Uint64("florb")) - fmt.Printf("%#v\n", nc.GlobalBool("global-nope")) - fmt.Printf("%#v\n", nc.GlobalBoolT("global-nerp")) - fmt.Printf("%#v\n", nc.GlobalDuration("global-howlong")) - fmt.Printf("%#v\n", nc.GlobalFloat64("global-hay")) - fmt.Printf("%#v\n", nc.GlobalGeneric("global-bloop")) - fmt.Printf("%#v\n", nc.GlobalInt("global-bips")) - fmt.Printf("%#v\n", nc.GlobalIntSlice("global-blups")) - fmt.Printf("%#v\n", nc.GlobalString("global-snurt")) - fmt.Printf("%#v\n", nc.GlobalStringSlice("global-snurkles")) - - fmt.Printf("%#v\n", nc.FlagNames()) - fmt.Printf("%#v\n", nc.GlobalFlagNames()) - fmt.Printf("%#v\n", nc.GlobalIsSet("wat")) - fmt.Printf("%#v\n", nc.GlobalSet("wat", "nope")) - fmt.Printf("%#v\n", nc.NArg()) - fmt.Printf("%#v\n", nc.NumFlags()) - fmt.Printf("%#v\n", nc.Parent()) - - nc.Set("wat", "also-nope") - - ec := cli.NewExitError("ohwell", 86) - fmt.Fprintf(c.App.Writer, "%d", ec.ExitCode()) - fmt.Printf("made it!\n") - return nil - } - - if os.Getenv("HEXY") != "" { - app.Writer = &hexWriter{} - app.ErrWriter = &hexWriter{} - } - - app.Metadata = map[string]interface{}{ - "layers": "many", - "explicable": false, - "whatever-values": 19.99, - } - - - // ignore error so we don't exit non-zero and break gfmrun README example tests - _ = app.Run(os.Args) -} - -func wopAction(c *cli.Context) error { - fmt.Fprintf(c.App.Writer, ":wave: over here, eh\n") - return nil -} -``` - -### Combining short Bool options - -Traditional use of boolean options using their shortnames look like this: -``` -# cmd foobar -s -o -``` - -Suppose you want users to be able to combine your bool options with their shortname. This -can be done using the **UseShortOptionHandling** bool in your commands. Suppose your program -has a two bool flags such as *serve* and *option* with the short options of *-o* and -*-s* respectively. With **UseShortOptionHandling** set to *true*, a user can use a syntax -like: -``` -# cmd foobar -so -``` - -If you enable the **UseShortOptionHandling*, then you must not use any flags that have a single -leading *-* or this will result in failures. For example, **-option** can no longer be used. Flags -with two leading dashes (such as **--options**) are still valid. - -## Contribution Guidelines - -See [./CONTRIBUTING.md](./CONTRIBUTING.md) |