title: Symfony get list of required PHP modules
body: <p>When deploying a Symfony application to another server I often need to wait for the <code>composer install</code> or <code>cache:clear</code> in order to know if a required <strong>PHP module</strong> is installed.</p>
  
  <p>E.g.</p>
  
  <pre><code> // Clearing the cache for the prod environment with debug false                                             
  
  
  In Imagine.php line 172:
  
    Gd not installed  
  </code></pre>
  
  <p>And so I have to run (or ask to the system engineer to run) <code>sudo apt-get install php-gd</code>.</p>
  
  <p>Is there a way to <strong>know this list before deploying</strong> the application?</p>
  
  <p>Something like:</p>
  
  <p><code>php bin/console debug:php-modules</code></p>
  
  <p><em>P.S. I would like to know a solution without using Docker.</em></p>