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diff --git a/node_modules/commander/Readme.md b/node_modules/commander/Readme.md index c846e7a2..095e2aef 100644 --- a/node_modules/commander/Readme.md +++ b/node_modules/commander/Readme.md @@ -1,428 +1,1134 @@ # Commander.js - -[](http://travis-ci.org/tj/commander.js) +[](https://github.com/tj/commander.js/actions?query=workflow%3A%22build%22) [](https://www.npmjs.org/package/commander) [](https://npmcharts.com/compare/commander?minimal=true) [](https://packagephobia.now.sh/result?p=commander) -[](https://gitter.im/tj/commander.js?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) - - The complete solution for [node.js](http://nodejs.org) command-line interfaces, inspired by Ruby's [commander](https://github.com/commander-rb/commander). - [API documentation](http://tj.github.com/commander.js/) +The complete solution for [node.js](http://nodejs.org) command-line interfaces. + +Read this in other languages: English | [简体中文](./Readme_zh-CN.md) + +- [Commander.js](#commanderjs) + - [Installation](#installation) + - [Quick Start](#quick-start) + - [Declaring _program_ variable](#declaring-program-variable) + - [Options](#options) + - [Common option types, boolean and value](#common-option-types-boolean-and-value) + - [Default option value](#default-option-value) + - [Other option types, negatable boolean and boolean|value](#other-option-types-negatable-boolean-and-booleanvalue) + - [Required option](#required-option) + - [Variadic option](#variadic-option) + - [Version option](#version-option) + - [More configuration](#more-configuration) + - [Custom option processing](#custom-option-processing) + - [Commands](#commands) + - [Command-arguments](#command-arguments) + - [More configuration](#more-configuration-1) + - [Custom argument processing](#custom-argument-processing) + - [Action handler](#action-handler) + - [Stand-alone executable (sub)commands](#stand-alone-executable-subcommands) + - [Life cycle hooks](#life-cycle-hooks) + - [Automated help](#automated-help) + - [Custom help](#custom-help) + - [Display help after errors](#display-help-after-errors) + - [Display help from code](#display-help-from-code) + - [.name](#name) + - [.usage](#usage) + - [.description and .summary](#description-and-summary) + - [.helpOption(flags, description)](#helpoptionflags-description) + - [.addHelpCommand()](#addhelpcommand) + - [More configuration](#more-configuration-2) + - [Custom event listeners](#custom-event-listeners) + - [Bits and pieces](#bits-and-pieces) + - [.parse() and .parseAsync()](#parse-and-parseasync) + - [Parsing Configuration](#parsing-configuration) + - [Legacy options as properties](#legacy-options-as-properties) + - [TypeScript](#typescript) + - [createCommand()](#createcommand) + - [Node options such as `--harmony`](#node-options-such-as---harmony) + - [Debugging stand-alone executable subcommands](#debugging-stand-alone-executable-subcommands) + - [Display error](#display-error) + - [Override exit and output handling](#override-exit-and-output-handling) + - [Additional documentation](#additional-documentation) + - [Support](#support) + - [Commander for enterprise](#commander-for-enterprise) + +For information about terms used in this document see: [terminology](./docs/terminology.md) ## Installation - $ npm install commander +```sh +npm install commander +``` + +## Quick Start + +You write code to describe your command line interface. +Commander looks after parsing the arguments into options and command-arguments, +displays usage errors for problems, and implements a help system. -## Option parsing +Commander is strict and displays an error for unrecognised options. +The two most used option types are a boolean option, and an option which takes its value from the following argument. -Options with commander are defined with the `.option()` method, also serving as documentation for the options. The example below parses args and options from `process.argv`, leaving remaining args as the `program.args` array which were not consumed by options. +Example file: [split.js](./examples/split.js) ```js -#!/usr/bin/env node +const { program } = require('commander'); + +program + .option('--first') + .option('-s, --separator <char>'); + +program.parse(); + +const options = program.opts(); +const limit = options.first ? 1 : undefined; +console.log(program.args[0].split(options.separator, limit)); +``` + +```console +$ node split.js -s / --fits a/b/c +error: unknown option '--fits' +(Did you mean --first?) +$ node split.js -s / --first a/b/c +[ 'a' ] +``` + +Here is a more complete program using a subcommand and with descriptions for the help. In a multi-command program, you have an action handler for each command (or stand-alone executables for the commands). -/** - * Module dependencies. - */ +Example file: [string-util.js](./examples/string-util.js) -var program = require('commander'); +```js +const { Command } = require('commander'); +const program = new Command(); program - .version('0.1.0') - .option('-p, --peppers', 'Add peppers') - .option('-P, --pineapple', 'Add pineapple') - .option('-b, --bbq-sauce', 'Add bbq sauce') - .option('-c, --cheese [type]', 'Add the specified type of cheese [marble]', 'marble') - .parse(process.argv); + .name('string-util') + .description('CLI to some JavaScript string utilities') + .version('0.8.0'); + +program.command('split') + .description('Split a string into substrings and display as an array') + .argument('<string>', 'string to split') + .option('--first', 'display just the first substring') + .option('-s, --separator <char>', 'separator character', ',') + .action((str, options) => { + const limit = options.first ? 1 : undefined; + console.log(str.split(options.separator, limit)); + }); -console.log('you ordered a pizza with:'); -if (program.peppers) console.log(' - peppers'); -if (program.pineapple) console.log(' - pineapple'); -if (program.bbqSauce) console.log(' - bbq'); -console.log(' - %s cheese', program.cheese); +program.parse(); ``` -Short flags may be passed as a single arg, for example `-abc` is equivalent to `-a -b -c`. Multi-word options such as "--template-engine" are camel-cased, becoming `program.templateEngine` etc. +```console +$ node string-util.js help split +Usage: string-util split [options] <string> + +Split a string into substrings and display as an array. + +Arguments: + string string to split + +Options: + --first display just the first substring + -s, --separator <char> separator character (default: ",") + -h, --help display help for command + +$ node string-util.js split --separator=/ a/b/c +[ 'a', 'b', 'c' ] +``` -Note that multi-word options starting with `--no` prefix negate the boolean value of the following word. For example, `--no-sauce` sets the value of `program.sauce` to false. +More samples can be found in the [examples](https://github.com/tj/commander.js/tree/master/examples) directory. + +## Declaring _program_ variable + +Commander exports a global object which is convenient for quick programs. +This is used in the examples in this README for brevity. + +```js +// CommonJS (.cjs) +const { program } = require('commander'); +``` + +For larger programs which may use commander in multiple ways, including unit testing, it is better to create a local Command object to use. ```js -#!/usr/bin/env node +// CommonJS (.cjs) +const { Command } = require('commander'); +const program = new Command(); +``` + +```js +// ECMAScript (.mjs) +import { Command } from 'commander'; +const program = new Command(); +``` + +```ts +// TypeScript (.ts) +import { Command } from 'commander'; +const program = new Command(); +``` + +## Options + +Options are defined with the `.option()` method, also serving as documentation for the options. Each option can have a short flag (single character) and a long name, separated by a comma or space or vertical bar ('|'). + +The parsed options can be accessed by calling `.opts()` on a `Command` object, and are passed to the action handler. + +Multi-word options such as "--template-engine" are camel-cased, becoming `program.opts().templateEngine` etc. + +An option and its option-argument can be separated by a space, or combined into the same argument. The option-argument can follow the short option directly or follow an `=` for a long option. + +```sh +serve -p 80 +serve -p80 +serve --port 80 +serve --port=80 +``` + +You can use `--` to indicate the end of the options, and any remaining arguments will be used without being interpreted. + +By default options on the command line are not positional, and can be specified before or after other arguments. -/** - * Module dependencies. - */ +There are additional related routines for when `.opts()` is not enough: -var program = require('commander'); +- `.optsWithGlobals()` returns merged local and global option values +- `.getOptionValue()` and `.setOptionValue()` work with a single option value +- `.getOptionValueSource()` and `.setOptionValueWithSource()` include where the option value came from +### Common option types, boolean and value + +The two most used option types are a boolean option, and an option which takes its value +from the following argument (declared with angle brackets like `--expect <value>`). Both are `undefined` unless specified on command line. + +Example file: [options-common.js](./examples/options-common.js) + +```js +program + .option('-d, --debug', 'output extra debugging') + .option('-s, --small', 'small pizza size') + .option('-p, --pizza-type <type>', 'flavour of pizza'); + +program.parse(process.argv); + +const options = program.opts(); +if (options.debug) console.log(options); +console.log('pizza details:'); +if (options.small) console.log('- small pizza size'); +if (options.pizzaType) console.log(`- ${options.pizzaType}`); +``` + +```console +$ pizza-options -p +error: option '-p, --pizza-type <type>' argument missing +$ pizza-options -d -s -p vegetarian +{ debug: true, small: true, pizzaType: 'vegetarian' } +pizza details: +- small pizza size +- vegetarian +$ pizza-options --pizza-type=cheese +pizza details: +- cheese +``` + +Multiple boolean short options may be combined together following the dash, and may be followed by a single short option taking a value. +For example `-d -s -p cheese` may be written as `-ds -p cheese` or even `-dsp cheese`. + +Options with an expected option-argument are greedy and will consume the following argument whatever the value. +So `--id -xyz` reads `-xyz` as the option-argument. + +`program.parse(arguments)` processes the arguments, leaving any args not consumed by the program options in the `program.args` array. The parameter is optional and defaults to `process.argv`. + +### Default option value + +You can specify a default value for an option. + +Example file: [options-defaults.js](./examples/options-defaults.js) + +```js +program + .option('-c, --cheese <type>', 'add the specified type of cheese', 'blue'); + +program.parse(); + +console.log(`cheese: ${program.opts().cheese}`); +``` + +```console +$ pizza-options +cheese: blue +$ pizza-options --cheese stilton +cheese: stilton +``` + +### Other option types, negatable boolean and boolean|value + +You can define a boolean option long name with a leading `no-` to set the option value to false when used. +Defined alone this also makes the option true by default. + +If you define `--foo` first, adding `--no-foo` does not change the default value from what it would +otherwise be. + +Example file: [options-negatable.js](./examples/options-negatable.js) + +```js program .option('--no-sauce', 'Remove sauce') - .parse(process.argv); + .option('--cheese <flavour>', 'cheese flavour', 'mozzarella') + .option('--no-cheese', 'plain with no cheese') + .parse(); + +const options = program.opts(); +const sauceStr = options.sauce ? 'sauce' : 'no sauce'; +const cheeseStr = (options.cheese === false) ? 'no cheese' : `${options.cheese} cheese`; +console.log(`You ordered a pizza with ${sauceStr} and ${cheeseStr}`); +``` -console.log('you ordered a pizza'); -if (program.sauce) console.log(' with sauce'); -else console.log(' without sauce'); +```console +$ pizza-options +You ordered a pizza with sauce and mozzarella cheese +$ pizza-options --sauce +error: unknown option '--sauce' +$ pizza-options --cheese=blue +You ordered a pizza with sauce and blue cheese +$ pizza-options --no-sauce --no-cheese +You ordered a pizza with no sauce and no cheese ``` -To get string arguments from options you will need to use angle brackets <> for required inputs or square brackets [] for optional inputs. +You can specify an option which may be used as a boolean option but may optionally take an option-argument +(declared with square brackets like `--optional [value]`). -e.g. ```.option('-m --myarg [myVar]', 'my super cool description')``` +Example file: [options-boolean-or-value.js](./examples/options-boolean-or-value.js) -Then to access the input if it was passed in. +```js +program + .option('-c, --cheese [type]', 'Add cheese with optional type'); -e.g. ```var myInput = program.myarg``` +program.parse(process.argv); + +const options = program.opts(); +if (options.cheese === undefined) console.log('no cheese'); +else if (options.cheese === true) console.log('add cheese'); +else console.log(`add cheese type ${options.cheese}`); +``` -**NOTE**: If you pass a argument without using brackets the example above will return true and not the value passed in. +```console +$ pizza-options +no cheese +$ pizza-options --cheese +add cheese +$ pizza-options --cheese mozzarella +add cheese type mozzarella +``` +Options with an optional option-argument are not greedy and will ignore arguments starting with a dash. +So `id` behaves as a boolean option for `--id -5`, but you can use a combined form if needed like `--id=-5`. -## Version option +For information about possible ambiguous cases, see [options taking varying arguments](./docs/options-taking-varying-arguments.md). -Calling the `version` implicitly adds the `-V` and `--version` options to the command. -When either of these options is present, the command prints the version number and exits. +### Required option - $ ./examples/pizza -V - 0.0.1 +You may specify a required (mandatory) option using `.requiredOption()`. The option must have a value after parsing, usually specified on the command line, or perhaps from a default value (say from environment). The method is otherwise the same as `.option()` in format, taking flags and description, and optional default value or custom processing. -If you want your program to respond to the `-v` option instead of the `-V` option, simply pass custom flags to the `version` method using the same syntax as the `option` method. +Example file: [options-required.js](./examples/options-required.js) ```js program - .version('0.0.1', '-v, --version') + .requiredOption('-c, --cheese <type>', 'pizza must have cheese'); + +program.parse(); ``` -The version flags can be named anything, but the long option is required. +```console +$ pizza +error: required option '-c, --cheese <type>' not specified +``` -## Command-specific options +### Variadic option -You can attach options to a command. +You may make an option variadic by appending `...` to the value placeholder when declaring the option. On the command line you +can then specify multiple option-arguments, and the parsed option value will be an array. The extra arguments +are read until the first argument starting with a dash. The special argument `--` stops option processing entirely. If a value +is specified in the same argument as the option then no further values are read. + +Example file: [options-variadic.js](./examples/options-variadic.js) ```js -#!/usr/bin/env node +program + .option('-n, --number <numbers...>', 'specify numbers') + .option('-l, --letter [letters...]', 'specify letters'); -var program = require('commander'); +program.parse(); +console.log('Options: ', program.opts()); +console.log('Remaining arguments: ', program.args); +``` + +```console +$ collect -n 1 2 3 --letter a b c +Options: { number: [ '1', '2', '3' ], letter: [ 'a', 'b', 'c' ] } +Remaining arguments: [] +$ collect --letter=A -n80 operand +Options: { number: [ '80' ], letter: [ 'A' ] } +Remaining arguments: [ 'operand' ] +$ collect --letter -n 1 -n 2 3 -- operand +Options: { number: [ '1', '2', '3' ], letter: true } +Remaining arguments: [ 'operand' ] +``` + +For information about possible ambiguous cases, see [options taking varying arguments](./docs/options-taking-varying-arguments.md). + +### Version option + +The optional `version` method adds handling for displaying the command version. The default option flags are `-V` and `--version`, and when present the command prints the version number and exits. + +```js +program.version('0.0.1'); +``` + +```console +$ ./examples/pizza -V +0.0.1 +``` + +You may change the flags and description by passing additional parameters to the `version` method, using +the same syntax for flags as the `option` method. + +```js +program.version('0.0.1', '-v, --vers', 'output the current version'); +``` + +### More configuration + +You can add most options using the `.option()` method, but there are some additional features available +by constructing an `Option` explicitly for less common cases. + +Example files: [options-extra.js](./examples/options-extra.js), [options-env.js](./examples/options-env.js), [options-conflicts.js](./examples/options-conflicts.js), [options-implies.js](./examples/options-implies.js) + +```js program - .command('rm <dir>') - .option('-r, --recursive', 'Remove recursively') - .action(function (dir, cmd) { - console.log('remove ' + dir + (cmd.recursive ? ' recursively' : '')) - }) + .addOption(new Option('-s, --secret').hideHelp()) + .addOption(new Option('-t, --timeout <delay>', 'timeout in seconds').default(60, 'one minute')) + .addOption(new Option('-d, --drink <size>', 'drink size').choices(['small', 'medium', 'large'])) + .addOption(new Option('-p, --port <number>', 'port number').env('PORT')) + .addOption(new Option('--donate [amount]', 'optional donation in dollars').preset('20').argParser(parseFloat)) + .addOption(new Option('--disable-server', 'disables the server').conflicts('port')) + .addOption(new Option('--free-drink', 'small drink included free ').implies({ drink: 'small' })); +``` + +```console +$ extra --help +Usage: help [options] -program.parse(process.argv) +Options: + -t, --timeout <delay> timeout in seconds (default: one minute) + -d, --drink <size> drink cup size (choices: "small", "medium", "large") + -p, --port <number> port number (env: PORT) + --donate [amount] optional donation in dollars (preset: "20") + --disable-server disables the server + --free-drink small drink included free + -h, --help display help for command + +$ extra --drink huge +error: option '-d, --drink <size>' argument 'huge' is invalid. Allowed choices are small, medium, large. + +$ PORT=80 extra --donate --free-drink +Options: { timeout: 60, donate: 20, port: '80', freeDrink: true, drink: 'small' } + +$ extra --disable-server --port 8000 +error: option '--disable-server' cannot be used with option '-p, --port <number>' ``` -A command's options are validated when the command is used. Any unknown options will be reported as an error. However, if an action-based command does not define an action, then the options are not validated. +Specify a required (mandatory) option using the `Option` method `.makeOptionMandatory()`. This matches the `Command` method [.requiredOption()](#required-option). + +### Custom option processing + +You may specify a function to do custom processing of option-arguments. The callback function receives two parameters, +the user specified option-argument and the previous value for the option. It returns the new value for the option. + +This allows you to coerce the option-argument to the desired type, or accumulate values, or do entirely custom processing. -## Coercion +You can optionally specify the default/starting value for the option after the function parameter. + +Example file: [options-custom-processing.js](./examples/options-custom-processing.js) ```js -function range(val) { - return val.split('..').map(Number); +function myParseInt(value, dummyPrevious) { + // parseInt takes a string and a radix + const parsedValue = parseInt(value, 10); + if (isNaN(parsedValue)) { + throw new commander.InvalidArgumentError('Not a number.'); + } + return parsedValue; } -function list(val) { - return val.split(','); +function increaseVerbosity(dummyValue, previous) { + return previous + 1; } -function collect(val, memo) { - memo.push(val); - return memo; +function collect(value, previous) { + return previous.concat([value]); } -function increaseVerbosity(v, total) { - return total + 1; +function commaSeparatedList(value, dummyPrevious) { + return value.split(','); } program - .version('0.1.0') - .usage('[options] <file ...>') - .option('-i, --integer <n>', 'An integer argument', parseInt) - .option('-f, --float <n>', 'A float argument', parseFloat) - .option('-r, --range <a>..<b>', 'A range', range) - .option('-l, --list <items>', 'A list', list) - .option('-o, --optional [value]', 'An optional value') - .option('-c, --collect [value]', 'A repeatable value', collect, []) - .option('-v, --verbose', 'A value that can be increased', increaseVerbosity, 0) - .parse(process.argv); - -console.log(' int: %j', program.integer); -console.log(' float: %j', program.float); -console.log(' optional: %j', program.optional); -program.range = program.range || []; -console.log(' range: %j..%j', program.range[0], program.range[1]); -console.log(' list: %j', program.list); -console.log(' collect: %j', program.collect); -console.log(' verbosity: %j', program.verbose); -console.log(' args: %j', program.args); -``` - -## Regular Expression + .option('-f, --float <number>', 'float argument', parseFloat) + .option('-i, --integer <number>', 'integer argument', myParseInt) + .option('-v, --verbose', 'verbosity that can be increased', increaseVerbosity, 0) + .option('-c, --collect <value>', 'repeatable value', collect, []) + .option('-l, --list <items>', 'comma separated list', commaSeparatedList) +; + +program.parse(); + +const options = program.opts(); +if (options.float !== undefined) console.log(`float: ${options.float}`); +if (options.integer !== undefined) console.log(`integer: ${options.integer}`); +if (options.verbose > 0) console.log(`verbosity: ${options.verbose}`); +if (options.collect.length > 0) console.log(options.collect); +if (options.list !== undefined) console.log(options.list); +``` + +```console +$ custom -f 1e2 +float: 100 +$ custom --integer 2 +integer: 2 +$ custom -v -v -v +verbose: 3 +$ custom -c a -c b -c c +[ 'a', 'b', 'c' ] +$ custom --list x,y,z +[ 'x', 'y', 'z' ] +``` + +## Commands + +You can specify (sub)commands using `.command()` or `.addCommand()`. There are two ways these can be implemented: using an action handler attached to the command, or as a stand-alone executable file (described in more detail later). The subcommands may be nested ([example](./examples/nestedCommands.js)). + +In the first parameter to `.command()` you specify the command name. You may append the command-arguments after the command name, or specify them separately using `.argument()`. The arguments may be `<required>` or `[optional]`, and the last argument may also be `variadic...`. + +You can use `.addCommand()` to add an already configured subcommand to the program. + +For example: + ```js +// Command implemented using action handler (description is supplied separately to `.command`) +// Returns new command for configuring. program - .version('0.1.0') - .option('-s --size <size>', 'Pizza size', /^(large|medium|small)$/i, 'medium') - .option('-d --drink [drink]', 'Drink', /^(coke|pepsi|izze)$/i) - .parse(process.argv); + .command('clone <source> [destination]') + .description('clone a repository into a newly created directory') + .action((source, destination) => { + console.log('clone command called'); + }); + +// Command implemented using stand-alone executable file, indicated by adding description as second parameter to `.command`. +// Returns `this` for adding more commands. +program + .command('start <service>', 'start named service') + .command('stop [service]', 'stop named service, or all if no name supplied'); -console.log(' size: %j', program.size); -console.log(' drink: %j', program.drink); +// Command prepared separately. +// Returns `this` for adding more commands. +program + .addCommand(build.makeBuildCommand()); ``` -## Variadic arguments +Configuration options can be passed with the call to `.command()` and `.addCommand()`. Specifying `hidden: true` will +remove the command from the generated help output. Specifying `isDefault: true` will run the subcommand if no other +subcommand is specified ([example](./examples/defaultCommand.js)). - The last argument of a command can be variadic, and only the last argument. To make an argument variadic you have to - append `...` to the argument name. Here is an example: +You can add alternative names for a command with `.alias()`. ([example](./examples/alias.js)) -```js -#!/usr/bin/env node +For safety, `.addCommand()` does not automatically copy the inherited settings from the parent command. There is a helper routine `.copyInheritedSettings()` for copying the settings when they are wanted. + +### Command-arguments -/** - * Module dependencies. - */ +For subcommands, you can specify the argument syntax in the call to `.command()` (as shown above). This +is the only method usable for subcommands implemented using a stand-alone executable, but for other subcommands +you can instead use the following method. -var program = require('commander'); +To configure a command, you can use `.argument()` to specify each expected command-argument. +You supply the argument name and an optional description. The argument may be `<required>` or `[optional]`. +You can specify a default value for an optional command-argument. +Example file: [argument.js](./examples/argument.js) + +```js program .version('0.1.0') - .command('rmdir <dir> [otherDirs...]') - .action(function (dir, otherDirs) { - console.log('rmdir %s', dir); - if (otherDirs) { - otherDirs.forEach(function (oDir) { - console.log('rmdir %s', oDir); - }); - } + .argument('<username>', 'user to login') + .argument('[password]', 'password for user, if required', 'no password given') + .action((username, password) => { + console.log('username:', username); + console.log('password:', password); }); +``` -program.parse(process.argv); + The last argument of a command can be variadic, and only the last argument. To make an argument variadic you + append `...` to the argument name. A variadic argument is passed to the action handler as an array. For example: + +```js +program + .version('0.1.0') + .command('rmdir') + .argument('<dirs...>') + .action(function (dirs) { + dirs.forEach((dir) => { + console.log('rmdir %s', dir); + }); + }); +``` + +There is a convenience method to add multiple arguments at once, but without descriptions: + +```js +program + .arguments('<username> <password>'); +``` + +#### More configuration + +There are some additional features available by constructing an `Argument` explicitly for less common cases. + +Example file: [arguments-extra.js](./examples/arguments-extra.js) + +```js +program + .addArgument(new commander.Argument('<drink-size>', 'drink cup size').choices(['small', 'medium', 'large'])) + .addArgument(new commander.Argument('[timeout]', 'timeout in seconds').default(60, 'one minute')) ``` - An `Array` is used for the value of a variadic argument. This applies to `program.args` as well as the argument passed - to your action as demonstrated above. +#### Custom argument processing + +You may specify a function to do custom processing of command-arguments (like for option-arguments). +The callback function receives two parameters, the user specified command-argument and the previous value for the argument. +It returns the new value for the argument. + +The processed argument values are passed to the action handler, and saved as `.processedArgs`. -## Specify the argument syntax +You can optionally specify the default/starting value for the argument after the function parameter. + +Example file: [arguments-custom-processing.js](./examples/arguments-custom-processing.js) ```js -#!/usr/bin/env node +program + .command('add') + .argument('<first>', 'integer argument', myParseInt) + .argument('[second]', 'integer argument', myParseInt, 1000) + .action((first, second) => { + console.log(`${first} + ${second} = ${first + second}`); + }) +; +``` + +### Action handler -var program = require('commander'); +The action handler gets passed a parameter for each command-argument you declared, and two additional parameters +which are the parsed options and the command object itself. +Example file: [thank.js](./examples/thank.js) + +```js program - .version('0.1.0') - .arguments('<cmd> [env]') - .action(function (cmd, env) { - cmdValue = cmd; - envValue = env; + .argument('<name>') + .option('-t, --title <honorific>', 'title to use before name') + .option('-d, --debug', 'display some debugging') + .action((name, options, command) => { + if (options.debug) { + console.error('Called %s with options %o', command.name(), options); + } + const title = options.title ? `${options.title} ` : ''; + console.log(`Thank-you ${title}${name}`); }); +``` -program.parse(process.argv); +If you prefer, you can work with the command directly and skip declaring the parameters for the action handler. The `this` keyword is set to the running command and can be used from a function expression (but not from an arrow function). -if (typeof cmdValue === 'undefined') { - console.error('no command given!'); - process.exit(1); -} -console.log('command:', cmdValue); -console.log('environment:', envValue || "no environment given"); +Example file: [action-this.js](./examples/action-this.js) + +```js +program + .command('serve') + .argument('<script>') + .option('-p, --port <number>', 'port number', 80) + .action(function() { + console.error('Run script %s on port %s', this.args[0], this.opts().port); + }); ``` -Angled brackets (e.g. `<cmd>`) indicate required input. Square brackets (e.g. `[env]`) indicate optional input. -## Git-style sub-commands +You may supply an `async` action handler, in which case you call `.parseAsync` rather than `.parse`. ```js -// file: ./examples/pm -var program = require('commander'); +async function run() { /* code goes here */ } + +async function main() { + program + .command('run') + .action(run); + await program.parseAsync(process.argv); +} +``` + +A command's options and arguments on the command line are validated when the command is used. Any unknown options or missing arguments will be reported as an error. You can suppress the unknown option checks with `.allowUnknownOption()`. By default it is not an error to +pass more arguments than declared, but you can make this an error with `.allowExcessArguments(false)`. + +### Stand-alone executable (sub)commands +When `.command()` is invoked with a description argument, this tells Commander that you're going to use stand-alone executables for subcommands. +Commander will search the files in the directory of the entry script for a file with the name combination `command-subcommand`, like `pm-install` or `pm-search` in the example below. The search includes trying common file extensions, like `.js`. +You may specify a custom name (and path) with the `executableFile` configuration option. +You may specify a custom search directory for subcommands with `.executableDir()`. + +You handle the options for an executable (sub)command in the executable, and don't declare them at the top-level. + +Example file: [pm](./examples/pm) + +```js program + .name('pm') .version('0.1.0') .command('install [name]', 'install one or more packages') .command('search [query]', 'search with optional query') - .command('list', 'list packages installed', {isDefault: true}) - .parse(process.argv); + .command('update', 'update installed packages', { executableFile: 'myUpdateSubCommand' }) + .command('list', 'list packages installed', { isDefault: true }); + +program.parse(process.argv); ``` -When `.command()` is invoked with a description argument, no `.action(callback)` should be called to handle sub-commands, otherwise there will be an error. This tells commander that you're going to use separate executables for sub-commands, much like `git(1)` and other popular tools. -The commander will try to search the executables in the directory of the entry script (like `./examples/pm`) with the name `program-command`, like `pm-install`, `pm-search`. +If the program is designed to be installed globally, make sure the executables have proper modes, like `755`. -Options can be passed with the call to `.command()`. Specifying `true` for `opts.noHelp` will remove the subcommand from the generated help output. Specifying `true` for `opts.isDefault` will run the subcommand if no other subcommand is specified. +### Life cycle hooks -If the program is designed to be installed globally, make sure the executables have proper modes, like `755`. +You can add callback hooks to a command for life cycle events. -### `--harmony` +Example file: [hook.js](./examples/hook.js) -You can enable `--harmony` option in two ways: -* Use `#! /usr/bin/env node --harmony` in the sub-commands scripts. Note some os version don’t support this pattern. -* Use the `--harmony` option when call the command, like `node --harmony examples/pm publish`. The `--harmony` option will be preserved when spawning sub-command process. +```js +program + .option('-t, --trace', 'display trace statements for commands') + .hook('preAction', (thisCommand, actionCommand) => { + if (thisCommand.opts().trace) { + console.log(`About to call action handler for subcommand: ${actionCommand.name()}`); + console.log('arguments: %O', actionCommand.args); + console.log('options: %o', actionCommand.opts()); + } + }); +``` + +The callback hook can be `async`, in which case you call `.parseAsync` rather than `.parse`. You can add multiple hooks per event. + +The supported events are: -## Automated --help +| event name | when hook called | callback parameters | +| :-- | :-- | :-- | +| `preAction`, `postAction` | before/after action handler for this command and its nested subcommands | `(thisCommand, actionCommand)` | +| `preSubcommand` | before parsing direct subcommand | `(thisCommand, subcommand)` | - The help information is auto-generated based on the information commander already knows about your program, so the following `--help` info is for free: +For an overview of the life cycle events see [parsing life cycle and hooks](./docs/parsing-and-hooks.md). -``` -$ ./examples/pizza --help +## Automated help + +The help information is auto-generated based on the information commander already knows about your program. The default +help option is `-h,--help`. + +Example file: [pizza](./examples/pizza) + +```console +$ node ./examples/pizza --help Usage: pizza [options] -An application for pizzas ordering +An application for pizza ordering Options: - -h, --help output usage information - -V, --version output the version number -p, --peppers Add peppers - -P, --pineapple Add pineapple - -b, --bbq Add bbq sauce - -c, --cheese <type> Add the specified type of cheese [marble] + -c, --cheese <type> Add the specified type of cheese (default: "marble") -C, --no-cheese You do not want any cheese + -h, --help display help for command ``` -## Custom help +A `help` command is added by default if your command has subcommands. It can be used alone, or with a subcommand name to show +further help for the subcommand. These are effectively the same if the `shell` program has implicit help: - You can display arbitrary `-h, --help` information - by listening for "--help". Commander will automatically - exit once you are done so that the remainder of your program - does not execute causing undesired behaviors, for example - in the following executable "stuff" will not output when - `--help` is used. +```sh +shell help +shell --help -```js -#!/usr/bin/env node +shell help spawn +shell spawn --help +``` + +Long descriptions are wrapped to fit the available width. (However, a description that includes a line-break followed by whitespace is assumed to be pre-formatted and not wrapped.) -/** - * Module dependencies. - */ +### Custom help -var program = require('commander'); +You can add extra text to be displayed along with the built-in help. +Example file: [custom-help](./examples/custom-help) + +```js program - .version('0.1.0') - .option('-f, --foo', 'enable some foo') - .option('-b, --bar', 'enable some bar') - .option('-B, --baz', 'enable some baz'); - -// must be before .parse() since -// node's emit() is immediate - -program.on('--help', function(){ - console.log('') - console.log('Examples:'); - console.log(' $ custom-help --help'); - console.log(' $ custom-help -h'); -}); + .option('-f, --foo', 'enable some foo'); -program.parse(process.argv); +program.addHelpText('after', ` -console.log('stuff'); +Example call: + $ custom-help --help`); ``` -Yields the following help output when `node script-name.js -h` or `node script-name.js --help` are run: +Yields the following help output: -``` +```Text Usage: custom-help [options] Options: - -h, --help output usage information - -V, --version output the version number - -f, --foo enable some foo - -b, --bar enable some bar - -B, --baz enable some baz + -f, --foo enable some foo + -h, --help display help for command -Examples: +Example call: $ custom-help --help - $ custom-help -h ``` -## .outputHelp(cb) +The positions in order displayed are: + +- `beforeAll`: add to the program for a global banner or header +- `before`: display extra information before built-in help +- `after`: display extra information after built-in help +- `afterAll`: add to the program for a global footer (epilog) + +The positions "beforeAll" and "afterAll" apply to the command and all its subcommands. + +The second parameter can be a string, or a function returning a string. The function is passed a context object for your convenience. The properties are: + +- error: a boolean for whether the help is being displayed due to a usage error +- command: the Command which is displaying the help -Output help information without exiting. -Optional callback cb allows post-processing of help text before it is displayed. +### Display help after errors -If you want to display help by default (e.g. if no command was provided), you can use something like: +The default behaviour for usage errors is to just display a short error message. +You can change the behaviour to show the full help or a custom help message after an error. ```js -var program = require('commander'); -var colors = require('colors'); +program.showHelpAfterError(); +// or +program.showHelpAfterError('(add --help for additional information)'); +``` + +```console +$ pizza --unknown +error: unknown option '--unknown' +(add --help for additional information) +``` +The default behaviour is to suggest correct spelling after an error for an unknown command or option. You +can disable this. + +```js +program.showSuggestionAfterError(false); +``` + +```console +$ pizza --hepl +error: unknown option '--hepl' +(Did you mean --help?) +``` + +### Display help from code + +`.help()`: display help information and exit immediately. You can optionally pass `{ error: true }` to display on stderr and exit with an error status. + +`.outputHelp()`: output help information without exiting. You can optionally pass `{ error: true }` to display on stderr. + +`.helpInformation()`: get the built-in command help information as a string for processing or displaying yourself. + +### .name + +The command name appears in the help, and is also used for locating stand-alone executable subcommands. + +You may specify the program name using `.name()` or in the Command constructor. For the program, Commander will +fallback to using the script name from the full arguments passed into `.parse()`. However, the script name varies +depending on how your program is launched so you may wish to specify it explicitly. + +```js +program.name('pizza'); +const pm = new Command('pm'); +``` + +Subcommands get a name when specified using `.command()`. If you create the subcommand yourself to use with `.addCommand()`, +then set the name using `.name()` or in the Command constructor. + +### .usage + +This allows you to customise the usage description in the first line of the help. Given: + +```js program - .version('0.1.0') - .command('getstream [url]', 'get stream URL') - .parse(process.argv); + .name("my-command") + .usage("[global options] command") +``` -if (!process.argv.slice(2).length) { - program.outputHelp(make_red); -} +The help will start with: -function make_red(txt) { - return colors.red(txt); //display the help text in red on the console -} +```Text +Usage: my-command [global options] command ``` -## .help(cb) +### .description and .summary + +The description appears in the help for the command. You can optionally supply a shorter +summary to use when listed as a subcommand of the program. - Output help information and exit immediately. - Optional callback cb allows post-processing of help text before it is displayed. +```js +program + .command("duplicate") + .summary("make a copy") + .description(`Make a copy of the current project. +This may require additional disk space. + `); +``` +### .helpOption(flags, description) -## Custom event listeners - You can execute custom actions by listening to command and option events. +By default every command has a help option. You may change the default help flags and description. Pass false to disable the built-in help option. ```js -program.on('option:verbose', function () { - process.env.VERBOSE = this.verbose; +program + .helpOption('-e, --HELP', 'read more information'); +``` + +### .addHelpCommand() + +A help command is added by default if your command has subcommands. You can explicitly turn on or off the implicit help command with `.addHelpCommand()` and `.addHelpCommand(false)`. + +You can both turn on and customise the help command by supplying the name and description: + +```js +program.addHelpCommand('assist [command]', 'show assistance'); +``` + +### More configuration + +The built-in help is formatted using the Help class. +You can configure the Help behaviour by modifying data properties and methods using `.configureHelp()`, or by subclassing using `.createHelp()` if you prefer. + +The data properties are: + +- `helpWidth`: specify the wrap width, useful for unit tests +- `sortSubcommands`: sort the subcommands alphabetically +- `sortOptions`: sort the options alphabetically +- `showGlobalOptions`: show a section with the global options from the parent command(s) + +You can override any method on the [Help](./lib/help.js) class. There are methods getting the visible lists of arguments, options, and subcommands. There are methods for formatting the items in the lists, with each item having a _term_ and _description_. Take a look at `.formatHelp()` to see how they are used. + +Example file: [configure-help.js](./examples/configure-help.js) + +```js +program.configureHelp({ + sortSubcommands: true, + subcommandTerm: (cmd) => cmd.name() // Just show the name, instead of short usage. }); +``` + +## Custom event listeners + +You can execute custom actions by listening to command and option events. -// error on unknown commands -program.on('command:*', function () { - console.error('Invalid command: %s\nSee --help for a list of available commands.', program.args.join(' ')); - process.exit(1); +```js +program.on('option:verbose', function () { + process.env.VERBOSE = this.opts().verbose; }); ``` -## Examples +## Bits and pieces + +### .parse() and .parseAsync() + +The first argument to `.parse` is the array of strings to parse. You may omit the parameter to implicitly use `process.argv`. + +If the arguments follow different conventions than node you can pass a `from` option in the second parameter: + +- 'node': default, `argv[0]` is the application and `argv[1]` is the script being run, with user parameters after that +- 'electron': `argv[1]` varies depending on whether the electron application is packaged +- 'user': all of the arguments from the user + +For example: ```js -var program = require('commander'); +program.parse(process.argv); // Explicit, node conventions +program.parse(); // Implicit, and auto-detect electron +program.parse(['-f', 'filename'], { from: 'user' }); +``` -program - .version('0.1.0') - .option('-C, --chdir <path>', 'change the working directory') - .option('-c, --config <path>', 'set config path. defaults to ./deploy.conf') - .option('-T, --no-tests', 'ignore test hook'); +### Parsing Configuration -program - .command('setup [env]') - .description('run setup commands for all envs') - .option("-s, --setup_mode [mode]", "Which setup mode to use") - .action(function(env, options){ - var mode = options.setup_mode || "normal"; - env = env || 'all'; - console.log('setup for %s env(s) with %s mode', env, mode); - }); +If the default parsing does not suit your needs, there are some behaviours to support other usage patterns. + +By default program options are recognised before and after subcommands. To only look for program options before subcommands, use `.enablePositionalOptions()`. This lets you use +an option for a different purpose in subcommands. + +Example file: [positional-options.js](./examples/positional-options.js) + +With positional options, the `-b` is a program option in the first line and a subcommand option in the second line: +```sh +program -b subcommand +program subcommand -b +``` + +By default options are recognised before and after command-arguments. To only process options that come +before the command-arguments, use `.passThroughOptions()`. This lets you pass the arguments and following options through to another program +without needing to use `--` to end the option processing. +To use pass through options in a subcommand, the program needs to enable positional options. + +Example file: [pass-through-options.js](./examples/pass-through-options.js) + +With pass through options, the `--port=80` is a program option in the first line and passed through as a command-argument in the second line: + +```sh +program --port=80 arg +program arg --port=80 +``` + +By default the option processing shows an error for an unknown option. To have an unknown option treated as an ordinary command-argument and continue looking for options, use `.allowUnknownOption()`. This lets you mix known and unknown options. + +By default the argument processing does not display an error for more command-arguments than expected. +To display an error for excess arguments, use`.allowExcessArguments(false)`. + +### Legacy options as properties + +Before Commander 7, the option values were stored as properties on the command. +This was convenient to code but the downside was possible clashes with +existing properties of `Command`. You can revert to the old behaviour to run unmodified legacy code by using `.storeOptionsAsProperties()`. + +```js program - .command('exec <cmd>') - .alias('ex') - .description('execute the given remote cmd') - .option("-e, --exec_mode <mode>", "Which exec mode to use") - .action(function(cmd, options){ - console.log('exec "%s" using %s mode', cmd, options.exec_mode); - }).on('--help', function() { - console.log(''); - console.log('Examples:'); - console.log(''); - console.log(' $ deploy exec sequential'); - console.log(' $ deploy exec async'); + .storeOptionsAsProperties() + .option('-d, --debug') + .action((commandAndOptions) => { + if (commandAndOptions.debug) { + console.error(`Called ${commandAndOptions.name()}`); + } }); +``` + +### TypeScript + +extra-typings: There is an optional project to infer extra type information from the option and argument definitions. +This adds strong typing to the options returned by `.opts()` and the parameters to `.action()`. +See [commander-js/extra-typings](https://github.com/commander-js/extra-typings) for more. + +``` +import { Command } from '@commander-js/extra-typings'; +``` + +ts-node: If you use `ts-node` and stand-alone executable subcommands written as `.ts` files, you need to call your program through node to get the subcommands called correctly. e.g. + +```sh +node -r ts-node/register pm.ts +``` + +### createCommand() + +This factory function creates a new command. It is exported and may be used instead of using `new`, like: + +```js +const { createCommand } = require('commander'); +const program = createCommand(); +``` + +`createCommand` is also a method of the Command object, and creates a new command rather than a subcommand. This gets used internally +when creating subcommands using `.command()`, and you may override it to +customise the new subcommand (example file [custom-command-class.js](./examples/custom-command-class.js)). + +### Node options such as `--harmony` + +You can enable `--harmony` option in two ways: + +- Use `#! /usr/bin/env node --harmony` in the subcommands scripts. (Note Windows does not support this pattern.) +- Use the `--harmony` option when call the command, like `node --harmony examples/pm publish`. The `--harmony` option will be preserved when spawning subcommand process. + +### Debugging stand-alone executable subcommands + +An executable subcommand is launched as a separate child process. + +If you are using the node inspector for [debugging](https://nodejs.org/en/docs/guides/debugging-getting-started/) executable subcommands using `node --inspect` et al, +the inspector port is incremented by 1 for the spawned subcommand. + +If you are using VSCode to debug executable subcommands you need to set the `"autoAttachChildProcesses": true` flag in your launch.json configuration. + +### Display error + +This routine is available to invoke the Commander error handling for your own error conditions. (See also the next section about exit handling.) + +As well as the error message, you can optionally specify the `exitCode` (used with `process.exit`) +and `code` (used with `CommanderError`). + +```js +program.error('Password must be longer than four characters'); +program.error('Custom processing has failed', { exitCode: 2, code: 'my.custom.error' }); +``` + +### Override exit and output handling + +By default Commander calls `process.exit` when it detects errors, or after displaying the help or version. You can override +this behaviour and optionally supply a callback. The default override throws a `CommanderError`. + +The override callback is passed a `CommanderError` with properties `exitCode` number, `code` string, and `message`. The default override behaviour is to throw the error, except for async handling of executable subcommand completion which carries on. The normal display of error messages or version or help +is not affected by the override which is called after the display. + +```js +program.exitOverride(); + +try { + program.parse(process.argv); +} catch (err) { + // custom processing... +} +``` + +By default Commander is configured for a command-line application and writes to stdout and stderr. +You can modify this behaviour for custom applications. In addition, you can modify the display of error messages. + +Example file: [configure-output.js](./examples/configure-output.js) + +```js +function errorColor(str) { + // Add ANSI escape codes to display text in red. + return `\x1b[31m${str}\x1b[0m`; +} program - .command('*') - .action(function(env){ - console.log('deploying "%s"', env); + .configureOutput({ + // Visibly override write routines as example! + writeOut: (str) => process.stdout.write(`[OUT] ${str}`), + writeErr: (str) => process.stdout.write(`[ERR] ${str}`), + // Highlight errors in color. + outputError: (str, write) => write(errorColor(str)) }); - -program.parse(process.argv); ``` -More Demos can be found in the [examples](https://github.com/tj/commander.js/tree/master/examples) directory. +### Additional documentation + +There is more information available about: + +- [deprecated](./docs/deprecated.md) features still supported for backwards compatibility +- [options taking varying arguments](./docs/options-taking-varying-arguments.md) +- [parsing life cycle and hooks](./docs/parsing-and-hooks.md) + +## Support + +The current version of Commander is fully supported on Long Term Support versions of Node.js, and requires at least v14. +(For older versions of Node.js, use an older version of Commander.) + +The main forum for free and community support is the project [Issues](https://github.com/tj/commander.js/issues) on GitHub. + +### Commander for enterprise -## License +Available as part of the Tidelift Subscription -[MIT](https://github.com/tj/commander.js/blob/master/LICENSE) +The maintainers of Commander and thousands of other packages are working with Tidelift to deliver commercial support and maintenance for the open source dependencies you use to build your applications. Save time, reduce risk, and improve code health, while paying the maintainers of the exact dependencies you use. [Learn more.](https://tidelift.com/subscription/pkg/npm-commander?utm_source=npm-commander&utm_medium=referral&utm_campaign=enterprise&utm_term=repo) |