code: protected function getSerializeVars($skip = array()) {
  		$vars = get_object_vars($this);
  		
  		$servars = array();
  		
  		foreach ($vars as $k=>$v) {
  			// skip what is in the array
  			if (in_array($k,$skip)) {
  				continue;
  			}
  			
  			// skip 2 standars properties as no sence to serialize them
  			if ($k == 'options' || $k == 'logger') {
  				continue;
  			}
  			$servars[] = $k;
  		}
  		return $servars;
  	}
docs: Returns list of properties to serialise.
  
  @param array $skip Defines what properties to skip