如何在PHP微服务中实现分布式事件驱动和触发

class UserRegisteredEvent {
    public $userId;
    public $email;

    public function __construct($userId, $email) {
        $this->userId = $userId;
        $this->email = $email;
    }
}

class EventPublisher {
    private $queue;

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

    public function publish($event) {
        $message = serialize($event);
        $this->queue->push($message);
    }
}

class EventSubscriber {
    private $handlers = [];

    public function subscribe($event, $handler) {
        $this->handlers[$event] = $handler;
    }

    public function handle($message) {
        $event = unserialize($message);
        $eventName = get_class($event);

        if (isset($this->handlers[$eventName])) {
            $handler = $this->handlers[$eventName];
            $handler($event);
        }
    }
}

class EventBus {
    private $queue;

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

    public function publish($event) {
        $message = serialize($event);
        $this->queue->enqueue($message);
    }

    public function subscribe($subscriber) {
        while (true) {
            $message = $this->queue->dequeue();
            $subscriber->handle($message);
        }
    }
}

// 实例化事件发布者
$eventPublisher = new EventPublisher($queue);

// 实例化事件订阅者
$eventSubscriber = new EventSubscriber();

// 定义事件处理函数
$eventHandler = function($event) {
    // 处理用户注册成功事件的代码
    echo "用户注册成功：{$event->userId}, {$event->email}" . PHP_EOL;
};

// 订阅事件
$eventSubscriber->subscribe('UserRegisteredEvent', $eventHandler);

// 当用户注册成功时，发布事件
$event = new UserRegisteredEvent(1, 'test@example.com');
$eventPublisher->publish($event);

// 开始监听事件总线
$eventBus = new EventBus($queue);
$eventBus->subscribe($eventSubscriber);