event

type Event interface {
	EventName() string    // Returns the name of the event (e.g., "UserCreated")
	EventID() string      // Returns a unique ID for this specific event instance
	Timestamp() time.Time // Returns the time when the event occurred

}

type EventBus interface {
	Publisher
	Subscriber
	// 如果事件总线是后台进程，可以添加 Start 和 Stop 方法来管理其生命周期
	Start(ctx context.Context) error
	Stop(ctx context.Context) error
}

type EventHandler func(ctx context.Context, event Event) error

type Publisher interface {
	Publish(ctx context.Context, event Event) error
}

type Subscriber interface {
	Subscribe(ctx context.Context, eventName string, handler EventHandler) error
	Unsubscribe(ctx context.Context, eventName string, handler EventHandler) error
}