Article

Using a self defined Zend_Loader

When you start writing with a Framework like Zend like I did in the last weeks, you probably are still haunted by all the bad habits of pseudo object orientated PHP design, using lots of require and include's. Zend_Loader doesn't seem to help at first, its just another command (Zend_Loader::loadClass or ::loadFile). It sucks to register lots of autoload paths too.

I wrote my own Zend_Loader child class. It grabs all include paths from a config File using the Zend_Config class, and completely frees you of thinking about includes.

class WWLoader extends Zend_Loader
{
    private static $dirs = NULL;
    
    public static function loadClass($class)
    {       
        if(self::$dirs===NULL) {
            //
            // Include directories of this application are saved in a configuration file. If it has not been
            // loaded before do so now and safe everything to the private static variable $dirs which will
            // then be used in further loadings
            //
            $dirs = array();
            $conf_app_path = new Zend_Config_Ini(sprintf('%s%s', constant('ZEND_CONFIG_PATH'), 'application.ini'), 'appincludepath');
            self::extractPaths($conf_app_path->toArray(), $dirs);
            self::$dirs = $dirs;
        }
        
        parent::loadClass($class, self::$dirs, true);
    }

    public static function autoload($class)
    {
        try {
            self::loadClass($class);
            return $class;
        } catch (Exception $e) {
            return false;
        }
    }
    
    /**
     * Given an array with subkeys of include paths this function unifies this array to
     * a single one and returns the result in the second argument $dirs which is given 
     * by reference.
     *
     * @param Array $array
     * @param Array $dirs
     */
    public static function extractPaths($array, &$dirs)
    {
        foreach($array AS $k => $v) {
            if(is_array($v)) {
                self::extractPaths($v, $dirs);
            } else {
                $dirs[] = $v;
            }
        }
    }
}

ZEND_CONFIG_PATH is the only constant I use in my application. I initialize the following at the beginning of my bootstrap file:

define('ZEND_CONFIG_PATH', dirname(__FILE__)."/../application/config/");

require_once 'Zend/Loader.php';
require_once dirname(__FILE__).'/../application/include/WWLoader.php';
Zend_Loader::registerAutoload();
Zend_Loader::registerAutoload('WWLoader');

After that, its just Objects.

Published: 2008-01-20 Tags: #ZendFramework