fix(dompdf): Relative images are not supported on DomPDF v0.8.0+ (#3172857 by...

      $logo_path = DRUPAL_ROOT . '/' . $logo_path;

    }

    $order->content['invoice_logo'] = array(

      '#value' => $logo_path,

      '#value' => _commerce_billy_pdf_base64_image($logo_path),

    );

  }

}

/**

 * Convert image path into Base64 image.

 *

 * @param string $image_path

 *   Valid image path to convert.

 *

 * @return string

 *   Base64 image.

 */

function _commerce_billy_pdf_base64_image($image_path) {

  // Check if image exists in local file system.

  if (file_exists($image_path)) {

    $image_data = base64_encode(file_get_contents($image_path));

    $mime_type = mime_content_type($image_path);

    // Image source format: "data:{mime};base64,{data};"

    return 'data:' . $mime_type . ';base64,' . $image_data;

  }

  // If the file cannot be found, post a watchdog message and display no logo.

  watchdog('commerce_billy_pdf', 'Invoice logo does not exist or cannot be found: %path',

    array('%path' => $image_path), WATCHDOG_ERROR);

  return '';

}

/**

 * Transforms HTML to PDF and outputs it to the browser.

 *