springcloud系列18——全局和单个禁用Feign Client对Hystrix的支持

野性酷女 2022-05-12 12:50 245阅读 0赞

## 全局禁用 ##

这个比较简单，在application.yml中配置：

feign:
      hystrix:
        enabled: false

加上这段配置就可以了。

## 禁用某个Feign Client对Hystrix的支持 ##

1.新建一个配置类

@Configuration public class Configuration2 { //Configuration2里面加上这个就禁用了UserFeignClient2的Hystrix @Bean @Scope("prototype") public Feign.Builder feignBuilder() { //feignBuilder方法默认返回HystrixFeign.Builder也就是说Feign默认支持Hystrix //现在改成Feign.Builder就禁用了Hystrix的支持 return Feign.builder(); } }

2.在FeignClient的注解上加入configturation

@FeignClient(name = "microservice-springcloud-movie",configuration = Configuration2.class,fallback = UserHystrixClientFallback2.class) public interface UserFeignClient2 { @RequestMapping(value = "/user/list") List<User> showUserList(); }

### 禁用单个Hystrix的示例代码 ###

说明：模块名：microservice-springcloud-movie-feign-without-hystrix

该模块创建了2个Feign Client，Feign Client1支持Hystrix，Feign Client2不支持Hystrix。

application.yaml

server:
      port: 7801
    
    spring:
      application:
        name: microservice-springcloud-movie-feign-without-hystrix
    
    eureka:
      client:
        healthcheck:
          enabled: true
        serviceUrl:
          defaultZone: http://localhost:8761/eureka
      instance:
        prefer-ip-address: true
        instance-id: ${spring.application.name}:${spring.cloud.client.ipAddress}:${spring.application.instance_id:${server.port}}
    
    # 启用feign对Hystrix的支持
    feign:
      hystrix:
        enabled: true
    #设置全局的超时时间
    hystrix:
      command:
        default:
          execution:
            isolation:
              thread:
                timeoutInMilliseconds: 5000

主类：

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

@FeignClient(name = "microservice-springcloud-user",fallback = UserHystrixClientFallback.class) public interface UserFeignClient { @RequestMapping(value = "/sample/{userId}",method = RequestMethod.GET) User findUserById(@PathVariable("userId") Long userId); }

@Component public class UserHystrixClientFallback implements UserFeignClient { @Override public User findUserById(Long userId) { User user = new User(); user.setId(0L); return user; } }

@Component public class UserHystrixClientFallback2 implements UserFeignClient2 { @Override public List<User> showUserList() { System.out.println("UserHystrixClientFallback2.showUserList() called."); return null; } }

@RestController public class MovieController { @Autowired private UserFeignClient userFeignClient; @Autowired private UserFeignClient2 userFeignClient2; @GetMapping("/user/{userId}") public User findUserById(@PathVariable Long userId) { return this.userFeignClient.findUserById(userId); } @GetMapping("/user/list") public List<User> listUser() { return this.userFeignClient2.showUserList(); } }

public class User { private Long id; private String username; private String name; private BigDecimal balance; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getName() { return name; } public void setName(String name) { this.name = name; } public BigDecimal getBalance() { return balance; } public void setBalance(BigDecimal balance) { this.balance = balance; } }

测试：  
1.启动eurake server；  
2.启动user服务；  
3.启动movie服务；  
4.启动microservice-springcloud-movie-feign-without-hystrix。

浏览器访问/user/1，正常：  
![19126325.jpg][]

浏览器访问/user/list，正常：  
![50332993.jpg][]

关闭movie服务，再次访问/user/list  
![54830306.jpg][]  
提示连接超时，说明Feign Client2的Hystrix是失效的。

关闭user服务，再次访问/user/1  
![75084381.jpg][]  
返回的是我们定义的回退方法的结果，说明Feign Client1的Hystrix是生效的。

如上，就达到了禁用某个Feign Client对Hystrix支持的效果。

[19126325.jpg]: http://omh46px9n.bkt.clouddn.com/18-6-30/19126325.jpg
[50332993.jpg]: http://omh46px9n.bkt.clouddn.com/18-6-30/50332993.jpg
[54830306.jpg]: http://omh46px9n.bkt.clouddn.com/18-6-30/54830306.jpg
[75084381.jpg]: http://omh46px9n.bkt.clouddn.com/18-6-30/75084381.jpg