Amber

A dependency-injection framework consisting of Models, Services, Views, and Events

Overview

Amber is a dependency-injection framework that further breaks down the Controller aspect of the popular Model-View-Controller pattern into separate entities that promotes reusability and testability.

Events

Events are user actions that alter the state of the application, generally by URL navigation or submitting data (GET, POST, PUT, etc).

Creating an event namespace, in this case a "global" namespace, that requires a user to be logged in, a "requires login" policy, would be defined like below.

  $resinite->router->setNamespace('','/',function($router){

    $router->addValues(array(
      'policies' => [
          'requires_login' => 'unauthorized'
        ]
    ));

  	$router->add('index','')->addValues(
  		array(
  			'service'=>'index',
  			'format'=>'html'
  		)
  	);

  });

This particular route matches a blank URL and gives it the alias 'index.' If the policy is validated, the service "index" will be executed. If the policy fails, an unauthorized responder will execute.

Policies

A policy enforces a specific condition before a service will execute. In our route, we want to enforce that a user is logged in. A "RequiresLoginPolicy" class has to be defined with a resolve method.

namespace Application\Policies;

class RequiresLoginPolicy extends \Amber\Policy\Resolvable {

  public function resolve($current_user) : bool {
    return $current_user;
  }

}

The current_user parameter will be an injected object, a resolver once executed.

Resolvers

Resolvers are custom objects that can be injected into policies, resolvers, and services. These can be custom defined objects or defaults defined in your application.

namespace Application\Resolvers;

class CurrentUser {
  public function __construct() {}

  public function resolve($session) {
    // find user from a session and return the found user or null
    return $this;
  }

}

Services

Services handle the user action. This is essentially a bare-bones Controller in the MVC pattern, with an execute method. The params parameter contains the URL parameters specified in the events (note this is subject to change to being a service property). You can also require any resolved policy results, in this case, the result from the CurrentUser resolver.

namespace Application\Services;

class IndexService
{
  public function execute($current_user, $params) : void
  {
    // do something with the current user and params
  }
}