3.2.2 Ribbon客戶端負載

負載均衡的概念

服務端負載均衡

客戶端負載均衡

Ribbon集成示例

Ribbon的核心知識

Ribbon相關的初始化方式

Ribbon的IRule

容錯機制

Ribbon與RestTemplate

Ribbon的基本使用

1. 引入相關jar

<dependency>
  <groupId>org.springframe.cloud</groupId>
  <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
</dependency>

2. 添加配置

server:
  port: 8083

spring:
  application:
    name: consumer-demo


##改造配置
eureka:
  client:
    enabled: false


##1:定義一個serverlist給我們使用負載均衡
##格式{servcid}:ribbon:listOfServers
hello-server:
  ribbon:
    listOfServers: localhost:8001,localhost:8002


logging:
  level:
    org:
      springframework:
        cloud: debug
    com:
      netflix: debug

3. 在啓動類上添加註解

@RibbonClients(

​ @RibbonClient(value = “hello-server”)

)

4. 改造請求

		@Autowired
    LoadBalancerClient loadBalancerClient;

    @GetMapping("index")
    public Object getIndex(){
        ServiceInstance serviceInstance = loadBalancerClient.choose("hello-server");
        String ip = serviceInstance.getHost();
        int port = serviceInstance.getPort();
        return restTemplate.getForObject("http://"+ip+":"+port,String.class,"");
    }

Ribbon重試機制啓動

引入jar包就可以啓動重試機制。

<dependency>
  <groupId>org.springframe.retry</groupId>
  <artifactId>spring-retry</artifactId>
</dependency>