Using A Named Class Method

You could specify a custom class method to call when the middleware executes using one of the following formats:

1. 'ClassName::methodName': lazy instantiate the object;
2. [Object, 'methodName']: pre-instantiate the object.

For example:

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

/* 1: define controller class 
 *
 * use \Psr\Http\Message\ServerRequestInterface as Request;
 * use \Psr\Http\Server\RequestHandlerInterface as Handler;
 * use \Psr\Http\Message\ResponseInterface as Response;
 *
 * class SomeController
 * {
 *     public function someMethod(Request $request, Handler $handler): Response
 *     {
 *         $name = $request->getAttribute('name');
 *
 *         $response = $handler->handle($request);
 *         $response->getBody()->write("Hello, $name");
 *
 *         return $response;
 *     }
 * }
 */

// 2: define route
$app->get('/hello/{name}', 'SomeController::someMethod');
$app->get('/hello/{name}', [new SomeController, 'someMethod']);

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

If instantiating your route controller class does not require any arguments to be supplied, then you may want to use the lazy instantiation method as it may be good for performance.

Anonymous Class With Named Class Method

PHP 7+ allows us to create anonymous classes. If you wanted to can call a specific class method in an anonymous class (when the route is handled), you could do so by using the format: [@AnonymousClass, 'methodName'] like so:

use \Psr\Http\Message\ServerRequestInterface;
use \Psr\Http\Message\ResponseInterface;
use \Psr\Http\Server\RequestHandlerInterface;

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

// define route
$app->get('/hello/{name}', [new class {
    public function someMethod(
        ServerRequestInterface $request, 
        RequestHandlerInterface $handler
    ): ResponseInterface 
    {
        $name = $request->getAttribute('name');
        
        $response = $handler->handle($request);
        $response->getBody()->write("Hello, $name");

        return $response;
    }
}, 'someMethod']);

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

Using A MiddlewareInterface Instance

A route itself can be treated as a middleware (i.e. if the router you're using implements such functionality — for example \BitFrame\Router\FastRouteRouter). In such instances, a router handler class must implement \Psr\Http\Server\MiddlewareInterface so that when the router middleware (including the route itself) is processed (as per the PSR-15 spec) the process() method is automatically called, for example:

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

/* 1: define controller class 
 *
 * use \Psr\Http\Message\ServerRequestInterface as Request;
 * use \Psr\Http\Server\RequestHandlerInterface as Handler;
 * use \Psr\Http\Message\ResponseInterface as Response;
 * use \Psr\Http\Server\MiddlewareInterface;
 *
 * class SomeController implements MiddlewareInterface
 * {
 *     public function process(Request $request, Handler $handler): Response
 *     {
 *         $name = $request->getAttribute('name');
 *
 *         $response = $handler->handle($request);
 *         $response->getBody()->write("Hello, $name");
 *
 *         return $response;
 *     }
 * }
 */

// 2: define route
$app->get('/hello/{name}', new SomeController);

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

Anonymous Class

In PHP 7+, you could use anonymous classes implementing \Psr\Http\Server\MiddlewareInterface like so:

use \Psr\Http\Message\ServerRequestInterface;
use \Psr\Http\Message\ResponseInterface;
use \Psr\Http\Server\RequestHandlerInterface;
use \Psr\Http\Server\MiddlewareInterface;

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

// define route
$app->get('/hello/{name}', new class implements MiddlewareInterface {
	public function process(
		ServerRequestInterface $request, 
		RequestHandlerInterface $handler
	): ResponseInterface 
	{
		$name = $request->getAttribute('name');
		
		$response = $handler->handle($request);
		$response->getBody()->write("Hello, $name");

		return $response;
	}
});

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

Using The Magic __invoke

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

/* 1: define controller class  
 *
 * use \Psr\Http\Message\ServerRequestInterface as Request;
 * use \Psr\Http\Message\ResponseInterface as Response;
 *
 * class SomeController
 * {
 *     public function __invoke(Request $request, Response $response, callable $next)
 *     {
 *         $name = $request->getAttribute('name');
 *         $response->getBody()->write("Hello, $name");
 *
 *         return $response;
 *     }
 * }
 */

// 2: define route
$app->get('/hello/{name}', new SomeController);

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

Using Functions

Anonymous Functions:

use \Psr\Http\Message\ServerRequestInterface as Request;
use \Psr\Http\Message\ResponseInterface as Response;

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

// define route
$app->get('/hello/{name}', function (Request $request, Response $response, callable $next) {
    $name = $request->getAttribute('name');
    $response->getBody()->write("Hello, $name");
    return $response;
});

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

Named Functions:

use \Psr\Http\Message\ServerRequestInterface as Request;
use \Psr\Http\Message\ResponseInterface as Response;

require '../vendor/autoload.php';

$app = new \BitFrame\Application;

// 1: define controller function
function controller(Request $request, Response $response, callable $next) {
    $name = $request->getAttribute('name');
    $response->getBody()->write("Hello, $name");
    return $response;
}

// 2: define route
$app->get('/hello/{name}', 'controller');

$app->run([
    \BitFrame\Message\DiactorosResponseEmitter::class,
    \BitFrame\Router\FastRouteRouter::class
]);

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