Feign负载均衡(基于客户端)

小半 • 2022年5月12日下午6:05 • 后端开发 • 阅读 233

Feign默认集成了Ribbon，与Ribbon不同的是，通过Feign只需要定义服务绑定接口且以声明式的方法，便捷的实现了服务调用。

这里将原来Ribbon实现的服务消费者做修改，修改为通过Feign实现

加入Feign依赖

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-feign</artifactId>
    <version>1.4.6.RELEASE</version>
</dependency>

编写feign接口，通过@ FeignClient（“服务名”），来指定调用哪个服务提供者

@FeignClient(value = "SPRINGCLOUD-PROVIDER-DEPT")
public interface DeptClientService {
    @GetMapping("/dept/{id}")
    public Dept queryById(@PathVariable("id") Long id);
    @GetMapping("/dept")
    public List<Dept> queryAll();
    @PostMapping("/dept")
    public int addDept(Dept dept);
}

启动类添加注解@EnableFeignClients开启Feign功能，可通过basePackages 指定包

@SpringBootApplication
@EnableEurekaClient
@EnableDiscoveryClient
@EnableFeignClients(basePackages = {"com.yyx.springcloud"})
public class FeignDeptConsumer_80 {
    public static void main(String[] args) {
        SpringApplication.run(FeignDeptConsumer_80.class,args);
    }
}

controller层注入Feign客户端DeptClientService来消费服务

@RestController
public class DeptConsumerController {

    @Autowired
    private DeptClientService deptClientService;
    @RequestMapping("/consumer/dept/add")
    public int add(Dept dept){
        return this.deptClientService.addDept(dept);
    }
    @RequestMapping("/consumer/dept/get/{deptno}")
    public Dept dept(@PathVariable("deptno") Long deptno){
        return this.deptClientService.queryById(deptno);
    }
    @RequestMapping("/consumer/dept/list")
    public List<Dept> dept(){
        return this.deptClientService.queryAll();
    }
}