Learning blog: [SpringCloud] Hystrix service fuse

The first is the service provider
project structure

import dependencies

        <!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-hystrix -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
            <version>2.2.10.RELEASE</version>
        </dependency>

Enable annotations on services that need to be downgraded @HystrixCommand(fallbackMethod = "hystrixGet")

@RestController
public class DeptController {
    
    
    @Autowired
    private DeptService service;

    @GetMapping("/dept/get/{id}")
    @HystrixCommand(fallbackMethod = "hystrixGet")
    public Dept get(@PathVariable("id") Long id){
    
    
        Dept dept = service.queryById(id);

        if(dept == null){
    
    
            throw new RuntimeException("id=>"+id+",不存在该用户");
        }

        return dept;
    }

    //备选方法
    public Dept hystrixGet(@PathVariable("id") Long id){
    
    
        return new Dept()
                .setDeptno(id)
                .setDname("id=>"+id+"无对应信息,null--@Hystrix")
                .setDb_source("MySQL中没有该数据库");
    }

}

Add fuse support @EnableHystrix to the main startup class

@SpringBootApplication
@EnableEurekaClient //服务启动后自动注册到Eureka中
@EnableDiscoveryClient  //服务发现
@EnableHystrix  //熔断支持
public class DeptProviderHystrix_8001 {
    
    
    public static void main(String[] args) {
    
    
        SpringApplication.run(DeptProviderHystrix_8001.class, args);
    }
}

When accessing non-existent users, trigger the fuse mechanism

without the server side of the fuse mechanism