9.Eureka服务发现+Ribbon+RestTemplate服务调用

order-service服务通过服务名称来代替 ip:port的方式访问user-service服务的接口。

原来的请求代码：

@Service
public class OrderServiceImpl implements OrderService {
 
    @Autowired
    private OrderMapper orderMapper;
 
    @Autowired
    private RestTemplate restTemplate;
 
    @Override
    public Order queryOrderById(Long orderId) {
        Order order = orderMapper.findById(orderId);
        String url = "http://localhost:8081/user/" + order.getUserId();
        User user = restTemplate.getForObject(url, User.class);
        order.setUser(user);
        return order;
    }
}

改造过后的代码：

1.添加负载均衡注解@LoadBalanced

@SpringBootApplication
@MapperScan("com.xkj.org.mapper")
public class OrderApplication {
 
    public static void main(String[] args) {
        SpringApplication.run(OrderApplication.class, args);
    }
 
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

2.调用代码

@Service
public class OrderServiceImpl implements OrderService {
 
    @Autowired
    private OrderMapper orderMapper;
 
    @Autowired
    private RestTemplate restTemplate;
 
    @Override
    public Order queryOrderById(Long orderId) {
        Order order = orderMapper.findById(orderId);
        String url = "http://user-service/user/" + order.getUserId();
        User user = restTemplate.getForObject(url, User.class);
        order.setUser(user);
        return order;
    }
}