title: How do I read from parameters.yml in a controller in symfony2?
body: <p>I have put a couple of custom variables in my app/config/parameters.yml.</p>
  
  <pre><code>parameters:
      api_pass: apipass
      api_user: apiuser
  </code></pre>
  
  <p>I need to access these from my controller, and have tried to fetch them with</p>
  
  <pre><code>$this-&gt;get('api_user');
  </code></pre>
  
  <p>from within my controller file. When I try this, I get this error message:</p>
  
  <pre><code>You have requested a non-existent service "api_user".
  </code></pre>
  
  <p>What is the correct way to do this?</p>