title: Structure of legacy project with Silex
body: <p>I have a very old flat PHP project. I would like to modernize the source files without changing the big and old database structure. I found the PHP Framework Symfony Silex. I like the micro structure of this framework it's not so complicated to understand. </p>
  
  <p>I have the following file structure:</p>
  
  <pre class="lang-none prettyprint-override"><code>- classes (The business logic)
  - web (index.php and all my controllers)
  - vendors
  </code></pre>
  
  <ul>
  <li>How can I include my business logic from the Silex app? Should I use <code>require_once('classes/file1.php');</code> in my <code>index.php</code>?</li>
  <li>How can I access the database from the business logic files?</li>
  </ul>