Yargs Spickzettel

Yargs hilft beim Erstellen interaktiver Kommandozeilen-Tools durch Argument-Parsing und elegante Hilfemenüs.

Grundlegende Verwendung

const argv = require('yargs').argv;

argv._         // Array of positional arguments: [ ... ]
argv.$0        // Executable name: "node bin/mybin"
argv.verbose   // Boolean / string flag value: --verbose

Versions- & Hilfeausgabe

const argv = require('yargs')
  // Version configuration
  .alias('v', 'version')
  .version(function() { return require('../package').version; })
  .describe('v', 'show version information')

  // Help configuration
  .alias('h', 'help')
  .help('help')
  .usage('Usage: $0 -x [num]')
  .showHelpOnFail(false, "Specify --help for available options")

Optionskonfiguration

  .option('f', {
    alias: 'file',
    describe: 'Path to target file',
    type: 'string', /* 'array' | 'boolean' | 'string' */
    nargs: 1,
    demand: true,
    demand: 'file is required',
    default: '/etc/passwd'
    // also supports: count: true, requiresArg: true
  })

  .options({
    f: { /* option hash */ }
  })

Befehle & Beispiele

  .example('$0 -f config.json', 'Run with configuration file')
  .epilog('Copyright 2026')
  .command('start', 'Start the server application')

Zählbare & stapelbare Flags

  .count('verbose')

// Passing -vvv results in:
argv.verbose // => 3

Strikter Modus (Strict Mode)

  .strict()

Programmatische Methoden

yargs.showHelp()
const helpText = yargs.help() // => string output