PrestaShop: Minifying HTML source code

PrestaShop 1.4 introduced a feature called “Minify HTML” to improve performance. In this how to you will find how to add this exciting feature to PrestaShop 1.3!

1. Download PrestaShop 1.5.6.3 (the latest version of 1.5 branch).
2. Extract prestashop/tools/minify_html/minify_html.class.php file from the package.
3. Copy minify_html.class.php file to tools/minify_html/ directory (you will have to create this directory).
4. Create a new file Media.php with the following content and put it to the class directory:

   <?php
   /*
   * 2007-2013 PrestaShop 
   *
   * NOTICE OF LICENSE
   *
   * This source file is subject to the Open Software License (OSL 3.0)
   * that is bundled with this package in the file LICENSE.txt.
   * It is also available through the world-wide-web at this URL:
   * http://opensource.org/licenses/osl-3.0.php
   * If you did not receive a copy of the license and are unable to
   * obtain it through the world-wide-web, please send an email
   * to license@prestashop.com so we can send you a copy immediately.
   *
   * DISCLAIMER
   *
   * Do not edit or add to this file if you wish to upgrade PrestaShop to newer
   * versions in the future. If you wish to customize PrestaShop for your
   * needs please refer to http://www.prestashop.com for more information.
   *
   *  @author PrestaShop SA <contact@prestashop.com>
   *  @copyright  2007-2013 PrestaShop SA
   *  @license    http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
   *  International Registered Trademark & Property of PrestaShop SA
   */
   
   class	Media extends ObjectModel
   {
   
   	public static function minifyHTML($html_content)
   	{
   		if (strlen($html_content) > 0)
   		{
   			//set an alphabetical order for args
   			/*$html_content = preg_replace_callback(
   				'/(<[a-zA-Z0-9]+)((\s*[a-zA-Z0-9]+=[\"\\\'][^\"\\\']*[\"\\\']\s*)*)>/',
   				array('Media', 'minifyHTMLpregCallback'),
   				$html_content,
   				Media::getBackTrackLimit());*/
   
   			require_once(_PS_TOOL_DIR_.'minify_html/minify_html.class.php');
   			$html_content = str_replace(chr(194).chr(160), '&nbsp;', $html_content);
   			if (trim($minified_content = Minify_HTML::minify($html_content, array('xhtml' => true))) !=  '')
   				$html_content = $minified_content;
   
   			return $html_content;
   		}
   		return false;
   	}
   
   	public static function minifyHTMLpregCallback($preg_matches)
   	{
   		$args = array();
   		preg_match_all('/[a-zA-Z0-9]+=[\"\\\'][^\"\\\']*[\"\\\']/is', $preg_matches[2], $args);
   		$args = $args[0];
   		sort($args);
   		// if there is no args in the balise, we don't write a space (avoid previous : <title >, now : <title>)
   		if (empty($args))
   			$output = $preg_matches[1].'>';
   		else
   			$output = $preg_matches[1].' '.implode(' ', $args).'>';
   		return $output;
   	}
   	
   	public static function getBackTrackLimit()
   	{
   		static $limit = null;
   		if ($limit === null)
   		{
   			$limit = @ini_get('pcre.backtrack_limit');
   			if (!$limit)
   				$limit = -1;
   		}
   
   		return $limit;
   	}
   
   }
   

5. Open config/smarty.config.inc.php file.

   Find:

   $smarty->debug_tpl		= _PS_ALL_THEMES_DIR_ . 'debug.tpl';
   

   After, add:

   function smartyMinifyHTML($tpl_output, &$smarty)
   {
       $tpl_output = Media::minifyHTML($tpl_output);
       return $tpl_output;
   }
   

   Find:

   $smarty->compile_check	= false;
   

   Before, add:

   $smarty->register_outputfilter('smartyMinifyHTML');
   

Save and close all files and it’s done!