staticServer.js

const http = require('http');
const url = require('url');
const path = require('path');
const fs = require('fs');
const port = process.argv[2] || 8000;

/**
 * Get the directory listing and convert them into links
 * @param {string[]} filesArr The array of example names
 * @param {string} baseDir The base directory
 * @returns {string} The html item linking to the example
 */
function formatDirToHTML(filesArr, baseDir) {
  filesArr = filesArr.map((currVal) => {
    return `<li><a href=${path.basename(baseDir)}/${currVal}>${currVal}</a></li>`;
  });

  return `<ul>${filesArr.join('\n')}</ul>`;
}

http.createServer((request, response) => {
  // get the path from the URL
  const uri = url.parse(request.url).pathname;

  // got to examples dir if not there already
  if (uri === '/') {
    response.writeHead(301, {Location: '/examples'});
    response.end();
    return;
  }

  // resolve current directory to the path
  const filename = path.join(process.cwd(), uri);

  fs.stat(filename, (error, stats) => {
    if (error) {
      response.writeHead(404, {'Content-Type': 'text/plain'});
      response.write('404 Not Found\n');
      response.end();
      return;
    }

    if (stats.isDirectory()) {
      fs.readdir(filename, (err, files) => {
        response.writeHead(200, {'Content-Type': 'text/html'});
        response.write(formatDirToHTML(files, filename));
        response.end();
      });
      return;
    }

    fs.readFile(filename, 'binary', (err, file) => {
      if (err) {
        response.writeHead(500, {'Content-Type': 'text/plain'});
        response.write(err + '\n');
        response.end();
        return;
      }

      response.writeHead(200);
      response.write(file, 'binary');
      response.end();
    });
  });
}).listen(parseInt(port, 10));

console.log('Static file server running at\n  => http://localhost:' + port + '/\nCTRL + C to shutdown');