Part of a Node program I wrote, just dealing with argument parsing, to show my sister how to do that.

parse_some_args.js

// Parse command line arguments with the Minimist library
const argv = require('minimist')(process.argv.slice(2));

// Main browser automation dependencies
const { chromium, firefox, webkit } = require('playwright');

// Other dependencies
const crypto = require('crypto');
const fse = require('fs-extra');
const path = require('path');
const url = require('url');
const validUrl = require('valid-url');

// Global constants
const _VERSION = '1.0.0';
const hashingAlgorithm = 'md5';
const jsDir = 'js';
const lastRuntimeOutputFilename = 'lastrun.txt';
const snapshotsDir = path.join('.', 'snapshots')
const targetUrlOutputFilename = 'url.txt';

// See if we should print help
if (argv['h'] || argv['help']) {
  console.info('  Usage:');
  console.info('    jswatch <target_url> [options]')
  console.info('  Options:');
  console.info('    --local-storage  Pass Base64 JSON string of how to set browser local storage')
  console.info('    -h, --help       Print this help')
  console.info('    -v, --version    Print version')
  process.exit(0);
}

// Print version information
if (argv['v'] || argv['version']) {
  console.info(_VERSION);
  process.exit(0);
}

// Need at least one argument for the target URL
if (0 == argv['_'].length) {
  console.error('Missing mandatory target (URL) argument. Pass -h or --help for info.');
  process.exit(1);  
}

// Validate target URL
const targetUrl = argv['_'][0];
if (false == validUrl.isUri(targetUrl)) {
  console.error('Given argument is not a valid URL.');
  process.exit(1);
}