static-server.mjs

#!/usr/bin/env node
import http from 'node:http';
import fs from 'node:fs';
import path from 'node:path';

const [, , rootArg, portArg] = process.argv;
if (!rootArg || !portArg) {
  console.error('Usage: node tools/static-server.mjs <dir> <port>');
  process.exit(1);
}
const ROOT = path.resolve(process.cwd(), rootArg);
const PORT = parseInt(portArg, 10);
if (isNaN(PORT) || PORT < 1 || PORT > 65535) {
  console.error('Invalid port number');
  process.exit(1);
}

const MIME = {
  '.html': 'text/html; charset=utf-8',
  '.js':   'text/javascript; charset=utf-8',
  '.mjs':  'text/javascript; charset=utf-8',
  '.css':  'text/css; charset=utf-8',
  '.wasm': 'application/wasm',
  '.json': 'application/json; charset=utf-8',
  '.png':  'image/png',
  '.jpg':  'image/jpeg',
  '.svg':  'image/svg+xml',
  '.txt':  'text/plain; charset=utf-8'
};

const server = http.createServer((req, res) => {
  const urlPath = decodeURIComponent(req.url.split('?')[0]);
  let filePath = path.join(ROOT, urlPath);
  if (filePath.endsWith('/')) filePath += 'index.html';

  // Prevent path traversal by ensuring filePath is within ROOT
  const relative = path.relative(ROOT, filePath);
  if (relative.startsWith('..') || path.isAbsolute(relative)) {
    res.statusCode = 403;
    res.end('Forbidden');
    return;
  }

  fs.stat(filePath, (err, stat) => {
    if (err || !stat.isFile()) {
      res.statusCode = 404;
      res.end('Not found');
      return;
    }
    const ext = path.extname(filePath).toLowerCase();
    res.setHeader('Content-Type', MIME[ext] || 'application/octet-stream');
    
    fs.createReadStream(filePath)
      .on('error', () => {
        res.statusCode = 500;
        res.end('Error reading file');
      })
      .pipe(res);
  });
});

server.listen(PORT, () => {
  console.log(`Static server running at http://localhost:${PORT}`);
  console.log(`Serving files from: ${ROOT}`);
});