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author | Michael Muré <batolettre@gmail.com> | 2018-12-23 17:11:37 +0100 |
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committer | Michael Muré <batolettre@gmail.com> | 2018-12-23 17:11:37 +0100 |
commit | 1410a1af75b1ab9ea3f980a7e372728f9a123abf (patch) | |
tree | e24db8f84c48b20158b1f1fd6d281d700421279c /vendor/github.com/urfave/cli/README.md | |
parent | 8fc15a032f021c855abf66ed303c003d57c340ea (diff) | |
download | git-bug-1410a1af75b1ab9ea3f980a7e372728f9a123abf.tar.gz |
upgrade gqlgen to v0.7.1
Diffstat (limited to 'vendor/github.com/urfave/cli/README.md')
-rw-r--r-- | vendor/github.com/urfave/cli/README.md | 1381 |
1 files changed, 1381 insertions, 0 deletions
diff --git a/vendor/github.com/urfave/cli/README.md b/vendor/github.com/urfave/cli/README.md new file mode 100644 index 00000000..2bbbd8ea --- /dev/null +++ b/vendor/github.com/urfave/cli/README.md @@ -0,0 +1,1381 @@ +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) + +**Notice:** 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 alternate input sources (YAML, TOML, and others)](#values-from-alternate-input-sources-yaml-toml-and-others) + * [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) +- [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 ( + "os" + + "github.com/urfave/cli" +) + +func main() { + cli.NewApp().Run(os.Args) +} +``` + +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" + "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 + } + + app.Run(os.Args) +} +``` + +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" + "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 + } + + app.Run(os.Args) +} +``` + +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" + "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 + } + + app.Run(os.Args) +} +``` + +### Flags + +Setting and querying flags is simple. + +<!-- { + "output": "Hello Nefertiti" +} --> +``` go +package main + +import ( + "fmt" + "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 + } + + app.Run(os.Args) +} +``` + +You can also set a destination variable for a flag, to which the content will be +scanned. + +<!-- { + "output": "Hello someone" +} --> +``` go +package main + +import ( + "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 + } + + app.Run(os.Args) +} +``` + +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 ( + "os" + + "github.com/urfave/cli" +) + +func main() { + app := cli.NewApp() + + app.Flags = []cli.Flag{ + cli.StringFlag{ + Name: "config, c", + Usage: "Load configuration from `FILE`", + }, + } + + app.Run(os.Args) +} +``` + +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 ( + "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", + }, + } + + app.Run(os.Args) +} +``` + +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 ( + "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)) + + app.Run(os.Args) +} +``` + +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 ( + "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", + }, + } + + app.Run(os.Args) +} +``` + +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 ( + "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", + }, + } + + app.Run(os.Args) +} +``` + +#### 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 the aboved specified formats 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" + "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 + + app.Run(os.Args) +} +``` + +### 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" + "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 + }, + }, + }, + }, + } + + app.Run(os.Args) +} +``` + +### 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 ( + "os" + + "github.com/urfave/cli" +) + +func main() { + app := cli.NewApp() + + app.Commands = []cli.Command{ + { + Name: "noop", + }, + { + Name: "add", + Category: "template", + }, + { + Name: "remove", + Category: "template", + }, + } + + app.Run(os.Args) +} +``` + +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 ( + "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 + } + + app.Run(os.Args) +} +``` + +### 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" + "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) + } + }, + }, + } + + app.Run(os.Args) +} +``` + +#### 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 ( + "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", + }, + } + app.Run(os.Args) +} +``` + +### 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" + "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") + } + + cli.NewApp().Run(os.Args) +} +``` + +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 ( + "os" + + "github.com/urfave/cli" +) + +func main() { + cli.HelpFlag = cli.BoolFlag{ + Name: "halp, haaaaalp", + Usage: "HALP", + EnvVar: "SHOW_HALP,HALPPLZ", + } + + cli.NewApp().Run(os.Args) +} +``` + +### 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 ( + "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" + app.Run(os.Args) +} +``` + +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" + "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" + app.Run(os.Args) +} +``` + +#### 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 ec + } + + if os.Getenv("HEXY") != "" { + app.Writer = &hexWriter{} + app.ErrWriter = &hexWriter{} + } + + app.Metadata = map[string]interface{}{ + "layers": "many", + "explicable": false, + "whatever-values": 19.99, + } + + app.Run(os.Args) +} + +func wopAction(c *cli.Context) error { + fmt.Fprintf(c.App.Writer, ":wave: over here, eh\n") + return nil +} +``` + +## Contribution Guidelines + +Feel free to put up a pull request to fix a bug or maybe add a feature. I will +give it a code review and make sure that it does not break backwards +compatibility. If I or any other collaborators agree that it is in line with +the vision of the project, we will work with you to get the code into +a mergeable state and merge it into the master branch. + +If you have contributed something significant to the project, we will most +likely add you as a collaborator. As a collaborator you are given the ability +to merge others pull requests. It is very important that new code does not +break existing code, so be careful about what code you do choose to merge. + +If you feel like you have contributed to the project but have not yet been +added as a collaborator, we probably forgot to add you, please open an issue. |