title: symfony2 twig check if a remote image exists
body: <p>based on <a href="https://stackoverflow.com/questions/14231967/symfony2-checking-if-file-exists">this</a> post</p>
  
  <p>I am trying to check if a remote image exists (loads correctly), and if it does, display it, othervise display default image. I have already done a twig extension and corrected the code but it always returns false though I definetely know that the image exists. My twig template code is as follows:</p>
  
  <pre><code>{% if file_exists(author.image) %} //always get false here so the default image is loaded
   &lt;img src="{{ author.image }}" alt="{{ author.name }}"&gt;//loads an image correctly if outside condition 
  {% else %}
   &lt;img src="/var/www/web/img/no_image.png" alt="no_image"&gt;
  {% endif %}
  </code></pre>
  
  <p>Any help is appreciated. Thank you.</p>
  
  <p><strong>UPD</strong> My twig function is as follows:</p>
  
  <pre><code>&lt;?php
  namespace AppBundle\Twig\Extension;
  class FileExtension extends \Twig_Extension
  {
  
  /**
   * Return the functions registered as twig extensions
   * 
   * @return array
   */
   public function getFunctions()
   {
      return array(
          new \Twig_SimpleFunction('file_exists', 'file_exists'),
      );
   }
  
   public function getName()
   {
      return 'app_file';
   }
  }
  </code></pre>