在Php和装饰模式中路由

Question

I do not know if I am using the term 'routing' correctly, but here is the situation:

I created an .htaccess file to 'process' (dunno if my term is right) the url of my application, like this :

RewriteEngine On

RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f

RewriteRule ^(.+)$ index.php?url=$1 [QSA,L]

Now I have this :

http://appname/controller/method/parameter
http://appname/$url[0]/$url[1]/$url[2]

What I did is:

1. setup a default controller, in case it is not specified in the url
2. setup a Controller wrapper

I did it like this

$target = new $url[0]()
$controller = new Controller($target)

The problem with that one is that I can't use the methods in the object I passed in the constructor of the Controller:

I resolved it like this :

class Controller {
  protected $target;
  protected $view;

  public function __construct($target, $view) {
    $this->target = $target;
    $this->view = $view;
  }

  public function __call($method, $arguments) {
    if (method_exists($this->target, $method)) {
        return call_user_func_array(array($this->target, $method), $arguments);
    }
  }
}

This is working fine, the problem occurs in the index where I did the routing, here it is

if(isset($url[2])){
    if(method_exists($controller, $url[1])){
         $controller->$url[1]($url[2])
    }
} else {
    if(method_exists($controller, $url[1])){
         $controller->$url[1]()
    }
}

where $controller = new Controller($target)

The problem is that the method doesn't exist, although I can use it directly without checking if method exist, how can I resolve this?

Answer 1

As you've already discovered, you aren't able to use method_exists when it is being handled by a magic __call method. However, you can add an extra public method to your Controller to get around this problem:

class Controller {
  protected $target;
  protected $view;

  public function __construct($target, $view) {
    $this->target = $target;
    $this->view = $view;
  }

  public function hasMethod($method) {
    return is_callable(array($this->target, $method));
  }

  public function __call($method, $arguments) {
    if (!is_callable(array($this->target, $method))) {
        throw new \BadMethodCallException("Method `$method` is not callable");
    }

    return call_user_func_array(array($this->target, $method), $arguments);
  }
}

So...

if(isset($url[2])){
    if($controller->hasMethod($url[1])){
         $controller->$url[1]($url[2])
    }
} else {
    if($controller->hasMethod($url[1])){
         $controller->$url[1]()
    }
}

EDIT: Changed method_exists to is_callable to ensure only public methods return true.