Mar24th

Extending CakePHP’s beforeFilter()

This is a simple addition to app_controller.php to allow a more customized beforeFilter() callback.

I set out to get a little more functionality out of the controller callback beforeFilter(). I had 2 requirements for this extended functionality:

  • Specify which actions to apply the callback to.
  • Ability to specify multiple methods beforeFilter would call.

Let me give a very simple example of how to use this snippet:
in your controller define $beforeFilter which is an array of methods to call and the parameters.


class TestingsController extends AppController
{
    var $name = 'Testings';
	var $beforeFilter = array('requireLogin'=>array('only'=>array('add','edit','delete')));

	function index(){}

	function view($id){}

	function add(){}

	function edit($id=null){}

	function delete($id){}

}

The $beforeFilter instance variable holds an array of methods to be called before your actions are called. In the example above, it says to call the ‘requireLogin’ method only when the ‘add’,'edit’,'delete’ actions are being called.

This next example shows you how to make certain actions excluded from the callback:


class TestingsController extends AppController
{
    var $name = 'Testings';
	var $beforeFilter = array('requireLogin'=>array('except'=>array('index')));

	function index(){}

	function view($id){}

	function add(){}

	function edit($id=null){}

	function delete($id){}

}

You can also send in a parameter called ‘args’ which will call your method with the args


var $beforeFilter = array('requireLogin'=>array('except'=>array('index'),
													'args'=>array('arg1','arg2')));

In order to make this all happen you need to place this method in your app_controller.php class.
It will get called before every action. If you have not defined $beforeFilter then it will skip any processing.


function beforeFilter(){
		if(empty($this->beforeFilter)) return true;
		$failures = false;
		foreach($this->beforeFilter as $func_name=>$func){
			$call_func = true;
			if(!empty($func['only'])){
				if(!in_array($this->action,$func['only']))
					$call_func = false;
			}
			if(!empty($func['except'])){
				if(in_array($this->action,$func['except']))
					$call_func = false;
			}
			if($call_func){
				$args = (isset($func['args'])) ? implode(',',$func['args']) : null;
				if(!$this->{$func_name}($args)){
					$failures = true;
					break;
				}
			}
		}
		return !$failures;
	}