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					429 lines
				
				12 KiB
			
		
		
			
		
	
	
					429 lines
				
				12 KiB
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											4 years ago
										 
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								# Commander.js
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								[](http://travis-ci.org/tj/commander.js)
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								[](https://www.npmjs.org/package/commander)
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								[](https://npmcharts.com/compare/commander?minimal=true)
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								[](https://packagephobia.now.sh/result?p=commander)
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								[](https://gitter.im/tj/commander.js?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
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								  The complete solution for [node.js](http://nodejs.org) command-line interfaces, inspired by Ruby's [commander](https://github.com/commander-rb/commander).  
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								  [API documentation](http://tj.github.com/commander.js/)
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								## Installation
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								    $ npm install commander
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								## Option parsing
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								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.
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								```js
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								#!/usr/bin/env node
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								/**
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								 * Module dependencies.
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								 */
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								var program = require('commander');
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								program
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								  .version('0.1.0')
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								  .option('-p, --peppers', 'Add peppers')
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								  .option('-P, --pineapple', 'Add pineapple')
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								  .option('-b, --bbq-sauce', 'Add bbq sauce')
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								  .option('-c, --cheese [type]', 'Add the specified type of cheese [marble]', 'marble')
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								  .parse(process.argv);
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								console.log('you ordered a pizza with:');
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								if (program.peppers) console.log('  - peppers');
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								if (program.pineapple) console.log('  - pineapple');
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								if (program.bbqSauce) console.log('  - bbq');
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								console.log('  - %s cheese', program.cheese);
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								```
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								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.
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								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.
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								```js
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								#!/usr/bin/env node
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								/**
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								 * Module dependencies.
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								 */
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								var program = require('commander');
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								program
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								  .option('--no-sauce', 'Remove sauce')
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								  .parse(process.argv);
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								console.log('you ordered a pizza');
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								if (program.sauce) console.log('  with sauce');
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								else console.log(' without sauce');
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								```
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								To get string arguments from options you will need to use angle brackets <> for required inputs or square brackets [] for optional inputs. 
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								e.g. ```.option('-m --myarg [myVar]', 'my super cool description')```
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								Then to access the input if it was passed in.
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								e.g. ```var myInput = program.myarg```
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								**NOTE**: If you pass a argument without using brackets the example above will return true and not the value passed in.
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								## Version option
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								Calling the `version` implicitly adds the `-V` and `--version` options to the command.
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								When either of these options is present, the command prints the version number and exits.
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								    $ ./examples/pizza -V
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								    0.0.1
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								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.
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								```js
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								program
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								  .version('0.0.1', '-v, --version')
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								```
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								The version flags can be named anything, but the long option is required.
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								## Command-specific options
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								You can attach options to a command.
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								```js
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								#!/usr/bin/env node
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								var program = require('commander');
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								program
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								  .command('rm <dir>')
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								  .option('-r, --recursive', 'Remove recursively')
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								  .action(function (dir, cmd) {
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								    console.log('remove ' + dir + (cmd.recursive ? ' recursively' : ''))
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								  })
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								program.parse(process.argv)
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								```
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								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.
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								## Coercion
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								```js
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								function range(val) {
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								  return val.split('..').map(Number);
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								}
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								function list(val) {
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								  return val.split(',');
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								}
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								function collect(val, memo) {
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								  memo.push(val);
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								  return memo;
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								}
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								function increaseVerbosity(v, total) {
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								  return total + 1;
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								}
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								program
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								  .version('0.1.0')
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								  .usage('[options] <file ...>')
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								  .option('-i, --integer <n>', 'An integer argument', parseInt)
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								  .option('-f, --float <n>', 'A float argument', parseFloat)
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								  .option('-r, --range <a>..<b>', 'A range', range)
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								  .option('-l, --list <items>', 'A list', list)
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								  .option('-o, --optional [value]', 'An optional value')
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								  .option('-c, --collect [value]', 'A repeatable value', collect, [])
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								  .option('-v, --verbose', 'A value that can be increased', increaseVerbosity, 0)
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								  .parse(process.argv);
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								console.log(' int: %j', program.integer);
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								console.log(' float: %j', program.float);
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								console.log(' optional: %j', program.optional);
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								program.range = program.range || [];
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								console.log(' range: %j..%j', program.range[0], program.range[1]);
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								console.log(' list: %j', program.list);
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								console.log(' collect: %j', program.collect);
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								console.log(' verbosity: %j', program.verbose);
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								console.log(' args: %j', program.args);
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								```
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								## Regular Expression
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								```js
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								program
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								  .version('0.1.0')
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								  .option('-s --size <size>', 'Pizza size', /^(large|medium|small)$/i, 'medium')
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								  .option('-d --drink [drink]', 'Drink', /^(coke|pepsi|izze)$/i)
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								  .parse(process.argv);
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								console.log(' size: %j', program.size);
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								console.log(' drink: %j', program.drink);
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								```
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								## Variadic arguments
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								 The last argument of a command can be variadic, and only the last argument.  To make an argument variadic you have to
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								 append `...` to the argument name.  Here is an example:
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								```js
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								#!/usr/bin/env node
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								/**
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								 * Module dependencies.
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								 */
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								var program = require('commander');
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								program
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								  .version('0.1.0')
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								  .command('rmdir <dir> [otherDirs...]')
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								  .action(function (dir, otherDirs) {
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								    console.log('rmdir %s', dir);
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								    if (otherDirs) {
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								      otherDirs.forEach(function (oDir) {
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								        console.log('rmdir %s', oDir);
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								      });
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								    }
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								  });
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								program.parse(process.argv);
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								```
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								 An `Array` is used for the value of a variadic argument.  This applies to `program.args` as well as the argument passed
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								 to your action as demonstrated above.
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								## Specify the argument syntax
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								```js
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								#!/usr/bin/env node
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								var program = require('commander');
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								program
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								  .version('0.1.0')
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								  .arguments('<cmd> [env]')
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								  .action(function (cmd, env) {
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								     cmdValue = cmd;
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								     envValue = env;
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								  });
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								program.parse(process.argv);
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								if (typeof cmdValue === 'undefined') {
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								   console.error('no command given!');
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								   process.exit(1);
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								}
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								console.log('command:', cmdValue);
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								console.log('environment:', envValue || "no environment given");
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								```
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								Angled brackets (e.g. `<cmd>`) indicate required input. Square brackets (e.g. `[env]`) indicate optional input.
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								## Git-style sub-commands
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								```js
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								// file: ./examples/pm
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								var program = require('commander');
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								program
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								  .version('0.1.0')
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								  .command('install [name]', 'install one or more packages')
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								  .command('search [query]', 'search with optional query')
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								  .command('list', 'list packages installed', {isDefault: true})
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								  .parse(process.argv);
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								```
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								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.  
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								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`.
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								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.
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								If the program is designed to be installed globally, make sure the executables have proper modes, like `755`.
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								### `--harmony`
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								You can enable `--harmony` option in two ways:
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								* Use `#! /usr/bin/env node --harmony` in the sub-commands scripts. Note some os version don’t support this pattern.
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								* 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.
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								## Automated --help
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								 The help information is auto-generated based on the information commander already knows about your program, so the following `--help` info is for free:
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```  
							 | 
						||
| 
								 | 
							
								$ ./examples/pizza --help
							 | 
						||
| 
								 | 
							
								Usage: pizza [options]
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								An application for pizzas 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, --no-cheese      You do not want any cheese
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## Custom 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.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								#!/usr/bin/env node
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								/**
							 | 
						||
| 
								 | 
							
								 * Module dependencies.
							 | 
						||
| 
								 | 
							
								 */
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								var program = require('commander');
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								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');
							 | 
						||
| 
								 | 
							
								});
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								program.parse(process.argv);
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								console.log('stuff');
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								Yields the following help output when `node script-name.js -h` or `node script-name.js --help` are run:
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								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
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								Examples:
							 | 
						||
| 
								 | 
							
								  $ custom-help --help
							 | 
						||
| 
								 | 
							
								  $ custom-help -h
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## .outputHelp(cb)
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								Output help information without exiting.
							 | 
						||
| 
								 | 
							
								Optional callback cb allows post-processing of help text before it is displayed.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								If you want to display help by default (e.g. if no command was provided), you can use something like:
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								var program = require('commander');
							 | 
						||
| 
								 | 
							
								var colors = require('colors');
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								program
							 | 
						||
| 
								 | 
							
								  .version('0.1.0')
							 | 
						||
| 
								 | 
							
								  .command('getstream [url]', 'get stream URL')
							 | 
						||
| 
								 | 
							
								  .parse(process.argv);
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								if (!process.argv.slice(2).length) {
							 | 
						||
| 
								 | 
							
								  program.outputHelp(make_red);
							 | 
						||
| 
								 | 
							
								}
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								function make_red(txt) {
							 | 
						||
| 
								 | 
							
								  return colors.red(txt); //display the help text in red on the console
							 | 
						||
| 
								 | 
							
								}
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## .help(cb)
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								  Output help information and exit immediately.
							 | 
						||
| 
								 | 
							
								  Optional callback cb allows post-processing of help text before it is displayed.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## Custom event listeners
							 | 
						||
| 
								 | 
							
								 You can execute custom actions by listening to command and option events.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								program.on('option:verbose', function () {
							 | 
						||
| 
								 | 
							
								  process.env.VERBOSE = this.verbose;
							 | 
						||
| 
								 | 
							
								});
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								// 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);
							 | 
						||
| 
								 | 
							
								});
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## Examples
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								var program = require('commander');
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								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');
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								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);
							 | 
						||
| 
								 | 
							
								  });
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								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');
							 | 
						||
| 
								 | 
							
								  });
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								program
							 | 
						||
| 
								 | 
							
								  .command('*')
							 | 
						||
| 
								 | 
							
								  .action(function(env){
							 | 
						||
| 
								 | 
							
								    console.log('deploying "%s"', env);
							 | 
						||
| 
								 | 
							
								  });
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								program.parse(process.argv);
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								More Demos can be found in the [examples](https://github.com/tj/commander.js/tree/master/examples) directory.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## License
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								[MIT](https://github.com/tj/commander.js/blob/master/LICENSE)
							 |