PHP MVC架构中控制器、数据服务与模型层的协作模式探究

// app/Models/UserModel.php
class UserModel
{
    public function createUser(array $userData): bool
    {
        // 实际的数据库插入逻辑，例如使用PDO或ORM
        echo "在数据库中创建用户: " . $userData['username'] . "\n";
        return true;
    }

    public function getUserByEmail(string $email): ?array
    {
        // 实际的数据库查询逻辑
        echo "从数据库中查询用户: " . $email . "\n";
        return ['id' => 1, 'username' => 'testuser', 'email' => $email]; // 模拟数据
    }
}

// app/Services/UserService.php
class UserService
{
    private UserModel $userModel;

    public function __construct(UserModel $userModel)
    {
        $this->userModel = $userModel;
    }

    public function registerUser(string $username, string $email, string $password): array
    {
        // 1. 数据验证
        if (empty($username) || empty($email) || empty($password)) {
            return ['success' => false, 'message' => '所有字段都是必填项。'];
        }
        if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
            return ['success' => false, 'message' => '邮箱格式不正确。'];
        }

        // 2. 检查邮箱是否已存在
        if ($this->userModel->getUserByEmail($email)) {
            return ['success' => false, 'message' => '该邮箱已被注册。'];
        }

        // 3. 密码加密 (实际应用中应使用更安全的哈希算法)
        $hashedPassword = password_hash($password, PASSWORD_DEFAULT);

        // 4. 调用模型层进行数据持久化
        $userData = [
            'username' => $username,
            'email' => $email,
            'password' => $hashedPassword,
            'created_at' => date('Y-m-d H:i:s')
        ];

        if ($this->userModel->createUser($userData)) {
            // 5. 可能的第三方通知或日志记录
            echo "用户注册成功，通知第三方系统...\n";
            return ['success' => true, 'message' => '用户注册成功！'];
        }

        return ['success' => false, 'message' => '用户注册失败。'];
    }
}

// app/Controllers/UserController.php
class UserController
{
    private UserService $userService;

    public function __construct(UserService $userService)
    {
        $this->userService = $userService;
    }

    public function register(): void
    {
        // 假设从POST请求获取数据
        $username = $_POST['username'] ?? '';
        $email = $_POST['email'] ?? '';
        $password = $_POST['password'] ?? '';

        $result = $this->userService->registerUser($username, $email, $password);

        if ($result['success']) {
            // 渲染成功视图或重定向
            echo "注册成功页面显示: " . $result['message'];
        } else {
            // 渲染失败视图并显示错误信息
            echo "注册失败页面显示: " . $result['message'];
        }
    }
}

// 模拟请求和执行
// $userModel = new UserModel();
// $userService = new UserService($userModel);
// $userController = new UserController($userService);
//
// $_POST['username'] = 'john_doe';
// $_POST['email'] = 'john@example.com';
// $_POST['password'] = 'password123';
// $userController->register();
//
// echo "\n---\n";
//
// // 模拟重复注册
// $_POST['email'] = 'john@example.com';
// $userController->register();