Sentinel整合Feign流程详细讲解-Java开发

要想整合Feign，首先要了解Feign的使用以及执行过程，然后看 Sentinel如何整合进去，文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧

修改84模块

84消费者调用提供者9003

Feign组件一般是消费侧

重点依赖

 <!--SpringCloud openfeign -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

激活Sentinel对Feign的支持

spring:
application:
name: nacos-order-consumer
cloud:
nacos:
discovery:
#Nacos服务注册中心地址
server-addr: localhost:8848
sentinel:
transport:
#配置Sentinel dashboard地址
dashboard: localhost:8080
#默认8719端口，假如被占用会自动从8719开始依次+1扫描,直至找到未被占用的端口
port: 8719
management:
endpoints:
web:
exposure:
include: '*'
# 激活Sentinel对Feign的支持
feign:
sentinel:
enabled: true

# 激活Sentinel对Feign的支持

feign:

sentinel:

enabled: true

增加业务类接口

@FeignClient(value = "nacos-payment-provider",fallback = PaymentFallbackService.class)//调用中关闭9003服务提供者
public interface PaymentService
{
    @GetMapping(value = "/paymentSQL/{id}")
    public CommonResult<Payment> paymentSQL(@PathVariable("id") Long id);
}

@FeignClient(value = "nacos-payment-provider",fallback =PaymentFallbackService.class)//调用中关闭9003服务提供者

@Component
public class PaymentFallbackService implements PaymentService
{
    @Override
    public CommonResult<Payment> paymentSQL(Long id)
    {
        return new CommonResult<>(444,"服务降级返回,没有该流水信息",new Payment(id, "errorSerial......"));
    }
}

调用失败的时候，就会调用重写的方法

修改控制类

 //==================OpenFeign
    @Resource
    private PaymentService paymentService;
    @GetMapping(value = "/consumer/openfeign/{id}")
    public CommonResult<Payment> paymentSQL(@PathVariable("id") Long id)
    {
        if(id == 4)
        {
            throw new RuntimeException("没有该id");
        }
        return paymentService.paymentSQL(id);
    }

添加@EnableFeignClients启动Feign的功能

@EnableDiscoveryClient
@SpringBootApplication
@EnableFeignClients
public class OrderNacosMain84
{
    public static void main(String[] args) {
            SpringApplication.run(OrderNacosMain84.class, args);
    }
}

测试

启动9003 9004 84 端口

访问：http://localhost:84/consumer/paymentSQL/1

测试84调用9003，此时故意关闭9003微服务提供者，看84消费侧自动降级，不会被耗死

熔断框架比较