commanderjs

Commander.js

Complete Commander.js framework guidance for building robust command-line interfaces with proper argument parsing, subcommands, options, and TypeScript support.

How to Use

Read individual reference files for detailed guidance:

• Core Basics
• Options & Flags
• Commands & Structure
• Action Handlers
• TypeScript Setup
• Practices & Patterns

Each reference file contains:

• API documentation and usage patterns
• Practical code examples with TypeScript
• Common patterns and best practices
• Error handling and validation techniques
• Migration guides from other frameworks

Quick Start

import { Command } from 'commander';

const program = new Command();

program
  .name('my-cli')
  .description('CLI tool description')
  .version('1.0.0');

program
  .command('build')
  .description('Build the project')
  .option('-o, --output <path>', 'Output directory')
  .option('-w, --watch', 'Watch for changes')
  .action((options) => {
    console.log('Building with options:', options);
  });

await program.parseAsync(process.argv);

Navigation Workflow

1. Start with core - Understand program setup and basic structure
2. Add options - Define flags, required options, and defaults
3. Structure commands - Create subcommands and command hierarchies
4. Implement actions - Write action handlers with async/await
5. Integrate TypeScript - Add proper typing and type safety
6. Validate parsing - Test with --help and invalid inputs to verify argument parsing and error handling
7. Apply best practices - Error handling, validation, and testing

Common Patterns

Single Command CLI

program
  .argument('<source>', 'Source file')
  .argument('[destination]', 'Destination file')
  .option('-f, --force', 'Force overwrite')
  .action((source, destination, options) => {
    // implementation
  });