SpringCloud -根据服务名获取服务运行实例并进行负载均衡

Nacos注册中心

每个服务启动之后都要向注册中心发送服务注册请求,注册中心可以和各个注册客户端自定义协议实现服务注册和发现。

  • pom.xml
xml 复制代码
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
  • 启动服务


获取服务实例测试
java 复制代码
@EnableDiscoveryClient
@SpringBootApplication
public class Main83
{
    public static void main(String[] args)
    {
        ConfigurableApplicationContext applicationContext = SpringApplication.run(Main83.class, args);

        DiscoveryClient discoveryClient = applicationContext.getBean(DiscoveryClient.class);
        List<ServiceInstance> instances = discoveryClient.getInstances("nacos-payment-provider");
        for (ServiceInstance instance : instances) {
            System.out.println("instance.getHost() = " + instance.getHost());
            System.out.println("instance.getPort() = " + instance.getPort());
        }

        NacosDiscoveryClient nacosDiscoveryClient = applicationContext.getBean(NacosDiscoveryClient.class);
        List<ServiceInstance> serviceInstances = nacosDiscoveryClient.getInstances("nacos-payment-provider");
        for (ServiceInstance instance : serviceInstances) {
            System.out.println("Nacos instance.getHost() = " + instance.getHost());
            System.out.println("instance.getPort() = " + instance.getPort());
        }

        LoadBalancerClient balancerClient = applicationContext.getBean(LoadBalancerClient.class);
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());

    }


}

在引入注册中心相关的依赖后,注册中心的相关API会实现SpringCloud规范,自动给容器中存入DiscoveryClient对象,引入了Nacos,就是NacosDiscoveryClient。通过DiscoveryClient接口提供的能力可以从注册中心实时拉取服务列表。

  • 负载均衡实现
    微服务在自动进行服务发现后,进行的是客户端负载均衡,也就是客户端自己维护了一套负载均衡算法,每次请求选择某一台服务器进行请求。

pom.xml

xml 复制代码
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-loadbalancer</artifactId>
        </dependency>
java 复制代码
LoadBalancerClient balancerClient = applicationContext.getBean(LoadBalancerClient.class);
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());
        System.out.println("balancerClient.choose(\"nacos-payment-provider\").getPort() = " + balancerClient.choose("nacos-payment-provider").getPort());

LoadBalancerClient类会自动使用容器中的DiscoveryClient进行服务的负载均衡。

相关推荐
Swift社区36 分钟前
从 JDK 1.8 切换到 JDK 21 时遇到 NoProviderFoundException 该如何解决?
java·开发语言
DKPT2 小时前
JVM中如何调优新生代和老生代?
java·jvm·笔记·学习·spring
phltxy2 小时前
JVM——Java虚拟机学习
java·jvm·学习
seabirdssss3 小时前
使用Spring Boot DevTools快速重启功能
java·spring boot·后端
喂完待续3 小时前
【序列晋升】29 Spring Cloud Task 微服务架构下的轻量级任务调度框架
java·spring·spring cloud·云原生·架构·big data·序列晋升
benben0443 小时前
ReAct模式解读
java·ai
轮到我狗叫了4 小时前
牛客.小红的子串牛客.kotori和抽卡牛客.循环汉诺塔牛客.ruby和薯条
java·开发语言·算法
Volunteer Technology5 小时前
三高项目-缓存设计
java·spring·缓存·高并发·高可用·高数据量
栗子~~5 小时前
bat脚本- 将jar 包批量安装到 Maven 本地仓库
java·maven·jar