# spring_cloud_demo

**Repository Path**: lxd040217/spring_cloud_demo

## Basic Information

- **Project Name**: spring_cloud_demo
- **Description**: 涉及spring cloud：feign ；gateway；hystrix；nacos
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2023-11-16
- **Last Updated**: 2023-11-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

### 分布式事务的mq解决方案
![分布式事务mq](Snipaste_2023-11-17_20-57-50.png)


 **具体代码为：order-service模块和bank-service模块** 

 **rabbitmq使用注意事项：**
 **在消费者和生产者启动类中加入jackson转换类：** 

```
    @Bean
    public MessageConverter jsonMessageConverter(){
        return new Jackson2JsonMessageConverter();
    }
```





### hystrix自定义降级配置：

1. orderController

```
@RestController
@RequestMapping("/order")
@Slf4j
public class OrderController {

   @Autowired
   private OrderService orderService;
   @Autowired
   private UserClient userClient;

   @GetMapping("{orderId}")
   @HystrixCommand(fallbackMethod = "queryOrderByUserIdFallback")
   public Order queryOrderByUserId(@PathVariable("orderId") Long orderId) throws InterruptedException {
      Thread.sleep(10000);
      // 根据id查询订单并返回
      Order order = orderService.queryOrderById(orderId);
      Long userId = order.getUserId();
      User user = userClient.findById(userId);
      order.setUser(user);
      return order;
   }
   //override the fallback method
   private Order queryOrderByUserIdFallback(Long orderId){
      Order order = new Order();
      order.setName("fall back method");
      log.info("queryOrderByUserId Fallback:{}",orderId);
      return order;
   }
}
```
2. USerClient


```
@FeignClient(value = "userservice",fallbackFactory = UserFallBackFactory.class)
public interface UserClient {
    @GetMapping("/user/{id}")
    User findById(@PathVariable("id") Long id);
}
@Component
class UserFallBackFactory implements FallbackFactory<UserClient> {
    private static final Logger LOGGER = LoggerFactory.getLogger(UserFallBackFactory.class);
    @Override
    public UserClient create(Throwable cause) {
        return new UserClient() {
            @Override
            public User findById(Long id) {
                LOGGER.error("调用异常:{}",cause);
                return null;
            }
        };
    }
}
```