Drush automagic site aliases

l.aliases.drushrc.php

<?php
/**
 * @file
 *   Setup site aliases for local sites.
 * 
 *   Expects the following setup:
 *     SITES_DIR/
 *       site.local/public_html
 *       site2.local/public_html
 * 
 * @todo
 *  - Detect Drupal (if it can be done efficiently)
 *  - Some kind of cache perhaps, this might get slow
 */

// Absolute path to sites directory
define('SITES_DIR', '/path/to/your/sites/');

// Name of public folder
define('PUBLIC_DIR', 'public_html');

// Local "domain"
define('DOMAIN', '.local');

// Automatically set up local site aliases
$di = new DirectoryIterator(SITES_DIR);
foreach ($di as $dir) {
  if ($dir->isDir() && !$dir->isDot()) {
    $path = $dir->getPathname() . '/' . PUBLIC_DIR;
    
    $aliases[$dir->getBasename(DOMAIN)] = array(
      'uri' => $dir->getFilename(),
      'path' => $path,
    );
  }
}