基於微服務框架Micronaut和Eventuate Tram實現分散式事務的開源案例

@Singleton
public class OrderService {

  @Inject
  private DomainEventPublisher domainEventPublisher;

  @PersistenceContext
  private EntityManager entityManager;

  @Transactional
  public Order createOrder(OrderDetails orderDetails) {
    ResultWithEvents<Order> orderWithEvents = Order.createOrder(orderDetails);
    Order order = orderWithEvents.result;
    entityManager.persist(order);
    domainEventPublisher.publish(Order.class, order.getId(), orderWithEvents.events);
    return order;
  }

  public void approveOrder(Long orderId) {
    Order order = Optional.ofNullable(entityManager.find(Order.class, orderId))
            .orElseThrow(() -> new IllegalArgumentException(String.format("order with id %s not found", orderId)));
    order.noteCreditReserved();
    OrderDetails orderDetails = new OrderDetails(order.getOrderDetails().getCustomerId(), new Money(order.getOrderDetails().getOrderTotal().getAmount()));
    domainEventPublisher.publish(Order.class,
            orderId, singletonList(new OrderApprovedEvent(orderDetails)));
  }

  public void rejectOrder(Long orderId) {
    Order order = Optional
            .ofNullable(entityManager.find(Order.class, orderId))
            .orElseThrow(() -> new IllegalArgumentException(String.format("order with id %s not found", orderId)));
    order.noteCreditReservationFailed();
    OrderDetails orderDetails = new OrderDetails(order.getOrderDetails().getCustomerId(), new Money(order.getOrderDetails().getOrderTotal().getAmount()));
    domainEventPublisher.publish(Order.class,
            orderId, singletonList(new OrderRejectedEvent(orderDetails)));
  }
}