Commander.js CLI-bibliotheek Spiekbrief

Commander.js Commander.js is de complete oplossing voor het bouwen van command-line interfaces in Node.js.

Basis CLI-installatie

const { program } = require('commander');

program
  .name('my-cli')
  .description('Sample CLI utility written in Node.js')
  .version('1.0.0');

---

Opties en vlaggen parsen

program
  .option('-p, --port <number>', 'specify port number', 3000)
  .option('-s, --silent', 'suppress terminal output')
  .option('-e, --env <mode>', 'execution environment', 'development')
  .requiredOption('-c, --config <path>', 'path to configuration file');

program.parse(process.argv);

const options = program.opts();
console.log(options.port, options.silent, options.config);

• <value>: Verplichte argumentwaarde.
• [value]: Optionele argumentwaarde.
• Vlaggen zonder parameters fungeren als booleaanse schakelaars.

---

Subcommando's

program
  .command('clone <source> [destination]')
  .description('clone a repository into a directory')
  .option('-b, --branch <name>', 'clone a specific branch')
  .action((source, destination, cmdOptions) => {
    console.log(`Cloning ${source} into ${destination || '.'}`);
  });

program.parse();

---

Helpweergave aanpassen

// Aangepaste voettekst toevoegen aan --help uitvoer
program.addHelpText('after', `
Example call:
  $ my-cli -c ./app.json --port 8080
`);

// Helptekst handmatig weergeven
program.outputHelp();