springcloud~~配置ribbon的负载均衡策略

配置ribbon的负载均衡策略

RoundRobinRule//轮询
RandomRule//随机
RetryRule//先按照轮询的策略获取服务，如果失败则在则定时间内会进行重试，获取可用的服务
WeightedResponseTimeRule//对轮询的扩展，相应速度越快的实例选择权重越大，越容易被选择
BestAvailableRule//会先过滤由于多次访问故障而处于断路器跳闸状态的服务，然后选择一个并发量小的服务
AvailabilityFilteringRule//先过滤故障实例，在选择并发量小的服务
ZoneAvoidanceRule//默认规则，符合判断server所在区域的性能和server的可用性现在服务

ribbon默认的是轮询策略RoundRobinRule

现在我们把策略改为随机RandomRule

新建model，service-consumer002

注意，spring-cloud-starter-netflix-eureka-client里面集成了ribbon，所以不用再特别的添加ribbon的依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

配置文件

server:
  port: 8202

spring:
  application:
    name: service-consumer002

eureka:
  client:
    register-with-eureka: true
    service-url:
      defaultZone: http://localhost:8300/eureka/,http://localhost:8302/eureka/

自己配置负载均衡策略的话，新建的包必须不能在@ComponentScan扫描的路径下，所以我们新建配置类的时候，必须在启动类所在包以外

在myrule包下面新建配置类

@Configuration
public class MyRule {
	@Bean
	public IRule mySelfRule(){
		return new RandomRule();//修改成随机的策略
	}
}

在主启动类所在包下面新建config包，在新建RestContextt配置类

@Configuration
public class RestContextt {
	@Bean
	@LoadBalanced//开启负载均衡
	public RestTemplate getRestTemlate(){
		return new RestTemplate();
	}
}

在新建controller包和ConsumerController类

@RestController
public class ConsumerController {
	@Value("${server.port}")
	private String port;

	private static final String URL = "http://SERVICE-PROVIDER";

	@Resource
	private RestContextt restContextt;

	@GetMapping("/consumer002")
	public String provider() {
		return restContextt.getRestTemlate().getForObject(URL + "/provider", String.class);
	}
}

在主启动类上添加注解

@SpringBootApplication
@EnableEurekaClient
//SERVICE-PROVIDER调用的服务名，configuration后面是更改的负载均衡策略的配置类
@RibbonClient(name = "SERVICE-PROVIDER", configuration = MyRule.class)
public class ServiceConsumer002 {
	public static void main(String[] args) {
		SpringApplication.run(ServiceConsumer002.class,args);
	}
}

这样就配置完成了