DipExample.php

<?php

declare(strict_types = 1);

// ******************************************************
// ******************************************************
//              💩🔴✋ HERENCIA ✋🔴💩
// ******************************************************
// ******************************************************

// namespace MySompany\MyProject\Infrastructure;

abstract class Controller
{
    protected function sendEmail(string $to, string $subject, string $content): void
    {
        // Envía email vía API Sendgrid
    }
    
    protected function saveOnDb(array $data): void
    {
        // Guarda datos en MySQL vía PDO
    }
    
    // …
}

// namespace MySompany\MyProject\Infrastructure;

// use MySompany\MyProject\Infrastructure\Controller;

// POST miwebmolona.com/users/

/**
 * @method(result)
 */
final class UserPostController extends Controller
{
    public function __invoke(array $request): void
    {
        parent::saveOnDb($request);
        parent::sendEmail($request['user_email']);
    }
}

// ******************************************************
// ******************************************************
//               🤔☝️ ¿COMPOSICIÓN? ☝️🤔
// ******************************************************
// ******************************************************

// namespace MySompany\MyProject\Infrastructure;

final class SendgridEmailSender
{
    public function __invoke(string $to, string $subject, string $content): void
    {
        // Envía email vía API Sendgrid
    }
}

// namespace MySompany\MyProject\Infrastructure;

// use MySompany\MyProject\Infrastructure\SendgridEmailSender;
// use MySompany\MyProject\Infrastructure\DbConnection;

final class VideoPutController
{
    private $emailSender;
    private $dbConnection;
    
    public function __construct()
    {
        $this->emailSender = new SendgridEmailSender();
        $this->dbConnection = new DbConnection(
            [
                'user' => 'root',
                'pass' => 'toor',
                'port' => '3306'
            ]
        );
    }
    
    public function __invoke(array $request): void
    {
        $this->dbConnection->save($request);
        $this->emailSender->__invoke($request['creator_email']);
    }
}

array_map($userPostController, $requests);

// ******************************************************
// ******************************************************
//        😬👌 COMPOSICIÓN INYECTANDO DEPS 👌😬
// ******************************************************
// ******************************************************

// namespace MySompany\MyProject\Infrastructure;

// use MySompany\MyProject\Infrastructure\SendgridEmailSender; // ☝️ Nos acoplamos a la implementación concreta
// use MySompany\MyProject\Infrastructure\DbConnection;

final class UserPatchController
{
    private $emailSender;
    private $dbConnection;
    
    public function __construct(
        SendgridEmailSender $emailSender,
        DbConnection $dbConnection
    ) {
        $this->emailSender = $emailSender;
        $this->dbConnection = $dbConnection;
    }
    
    public function __invoke(array $request): void
    {
        $this->dbConnection->save($request);
        $this->emailSender->__invoke($request['user_email']);
    }
}

// ******************************************************
// ******************************************************
//      🤟🔝🙌 COMPOSICIÓN INVIRTIENDO DEPS 🔝🙌🤟
// ******************************************************
// ******************************************************

// namespace MySompany\MyProject\Domain;

interface EmailSender
{
    public function __invoke(string $to, string $subject, string $content): void;
}

// namespace MySompany\MyProject\Infrastructure;

// use MySompany\MyProject\Domain\EmailSender;

final class SendgridEmailSender implements EmailSender
{
    public function __invoke(string $to, string $subject, string $content): void
    {
        // Envía email vía API Sendgrid
    }
}

// namespace MySompany\MyProject\Infrastructure;

// use MySompany\MyProject\Domain\EmailSender; // ☝️ Nos acoplamos a la interface, no a la implementación concreta

final class UserPatchController
{
    private $emailSender;
    private $dbConnection;
    
    public function __construct(
        EmailSender $emailSender,
        DbConnection $dbConnection
    ) {
        $this->emailSender = $emailSender;
        $this->dbConnection = $dbConnection;
    }
    
    public function __invoke(array $request): void
    {
        $this->dbConnection->save($request);
        $this->emailSender->__invoke($request['user_email']);
    }
}

final class ProductionContainer
{
    //$emailSender = new SendgridEmailSender(); // ☝️ Podemos cambiar la implementación de la interface que usamos sin modificar cliente (UserPatchController)
    $emailSender = new MandrillEmailSender();
    $dbConnection = new DbConnection(['…']);

    $userPostController = new UserPatchController($emailSender, $dbConnection);
}