服务降级

mock只出现在非业务异常(比如超时,网络异常等等)时执行. 他的配置支持两种:

布尔值,默认false,如果配置为true,则默认使用mock类名,即类名+Mock后缀return null.可以很简单的忽略掉异常

设置成return null

消费者dubbo配置

dubbo: application: name: dubbo-springboot-consumer scan: base-packages: com.ql.controller protocol: name: dubbo port: 20990 registry: client: curator address: zookeeper://127.0.0.1:2181?backup=127.0.0.1:2182,127.0.0.1:2183 consumer: mock: return null check: false #启动时不检查服务

controller

@RestController @RequestMapping("hello") public class HelloController { @DubboReference(version = "1.0.0") private HelloService helloService; @RequestMapping(value = "sayHello") public String sayHello(){ String s = helloService.sayHello(); System.out.println(s); return s; } }

service实现

@DubboService(version = "1.0.0") @Service public class HelloServiceImpl implements HelloService { @Override public String sayHello() { return "服务被成功调用了"; } }

interface

public interface HelloService { String sayHello(); }

访问对比

这里使用关闭服务提供者来模拟非业务异常,所以需要设置consumer.check=false

成功访问时

关闭服务提供者模拟非业务异常,未进行服务降级

进行mock设置return null后

mock设置成true

消费者

dubbo: application: name: dubbo-springboot-consumer scan: base-packages: com.ql.controller protocol: name: dubbo port: 20990 registry: client: curator address: zookeeper://127.0.0.1:2181?backup=127.0.0.1:2182,127.0.0.1:2183 consumer: mock: true check: false

在公共接口中使用类名+Mock后缀进行自定义

创建HelloServiceMock实现HelloService

/** * @author qinlei * @description todo * @date 2020/10/20 15:20 */ public class HelloServiceMock implements HelloService{ @Override public String sayHello() { System.out.println("服务调用失败..."); return null; } }

其他配置不变

重启消费者,同样不启动提供者

使用springcloud的hystrix集成dubbo

pom文件添加依赖

这里注意引入的依赖版本需要和你得springboot版本一致,否则会报错

<!--springcloud hystrix 依赖--> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-hystrix</artifactId> <version>2.1.3.RELEASE</version> </dependency>

提供者

暴露方法上增加@HystrixCommand,这样该方法就会经过Hystrix代理了

/** * @author qinlei * @description todo * @date 2020/10/20 14:52 */ @DubboService(version = "1.0.0") @Service public class HelloServiceImpl implements HelloService { @Override @HystrixCommand //表示该方法被hystrix代理了,出现异常就会熔断 public String sayHello() { return "服务被成功调用了"; } }

消费者

yml文件配置Hystrix

hystrix: command: default: execution: isolation: thread: timeoutInMilliseconds: 4000 #超时时间

启动类添加@EnableHystrix ,开启熔断器服务

/** * @author qinlei * @description todo * @date 2020/10/20 15:08 */ @SpringBootApplication @EnableDubbo @EnableHystrix //开启熔断器服务 public class ConsumerApplication { public static void main(String[] args) { SpringApplication.run(ConsumerApplication.class,args); } }

调用该提供者的方法时,添加@HystrixCommand,并指定出错时的回调方法

/** * @author qinlei * @description todo * @date 2020/10/20 15:01 */ @RestController @RequestMapping("hello") public class HelloController { @DubboReference(version = "1.0.0") private HelloService helloService; @HystrixCommand(fallbackMethod = "hello") @RequestMapping(value = "sayHello") public String sayHello(){ String s = helloService.sayHello(); System.out.println(s); return s; } /** * 服务熔断的回调方法 */ public String hello(){ System.out.println("服务熔断了..."); return ("服务熔断了..."); } }

同样不启动提供者,模拟超时,设置启动不检查service

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demo地址:

https://github.com/qlanto224/dubbo-springboot.git

觉得有用的,感谢您一赞的支持