Developing a Dispatcher in Your Own MVC Framework

Let's recall the current contents of the file index.php:

<?php
	namespace Core;
	
	error_reporting(E_ALL);
	ini_set('display_errors', 'on');
	
	spl_autoload_register(function($class) {
		// your autoload implementation
	});
	
	$routes = require $_SERVER['DOCUMENT_ROOT'] . '/project/config/routes.php';
	
	$track = ( new Router ) -> getTrack($routes, $_SERVER['REQUEST_URI']);
?>

As you can see, for now our router returns an object of the Track class, containing the controller name, action name, and parameters from the address bar. Furthermore, in the previous lesson, we created the parent of all controllers.

Now we can make it so that the method of the controller, whose data is contained in our variable $track, is called.

A special class, Dispatcher, will handle this. The dispatcher will receive an object of the Track class and, based on its data, create an object of the specified class, call the method of that class, passing parameters to this method.

Let's add the dispatcher call to the file index.php:

<?php
	namespace Core;
	
	error_reporting(E_ALL);
	ini_set('display_errors', 'on');
	
	spl_autoload_register(function($class) {
		// your autoload implementation
	});
	
	$routes = require $_SERVER['DOCUMENT_ROOT'] . '/project/config/routes.php';
	
	$track = ( new Router ) -> getTrack($routes, $_SERVER['REQUEST_URI']);
	
	// Dispatcher call:
	$page  = ( new Dispatcher ) -> getPage($track);
?>

Calling the getPage method of our dispatcher will call the controller's render method and return what that method call returned. As you already know from the previous lesson, the controller's render method returns an object of the Page class.

Here is the stub of our Dispatcher class:

<?php
	namespace Core;
	
	class Dispatcher
	{
		public function getPage(Track $track)
		{
			...code
			return controller -> render(parameters);
		}
	}
?>

Using my stub, implement the described class Dispatcher. Test its operation. If you have difficulties, look at the source code in the files of my made educational framework.