Nacos注册/配置中心

一、Nacos 注册/配置中心

文章目录

[一、Nacos 注册/配置中心](#一、Nacos 注册/配置中心)
- [1. 服务注册](#1. 服务注册)
- [2. 服务发现](#2. 服务发现)
- [3. 远程调用](#3. 远程调用)
- [4. 负载均衡](#4. 负载均衡)

1. 服务注册

引入依赖

xml 复制代码

<dependency>  
    <groupId>com.alibaba.cloud</groupId>  
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>  
</dependency>

整合配置

properties 复制代码

spring.application.name=service-order  
server.port=8000  
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848

2. 服务发现

开启服务发现

java 复制代码

@EnableDiscoveryClient  //开启服务发现功能  
@SpringBootApplication  
public class ProductMainApplication {  
  
    public static void main(String[] args) {  
        SpringApplication.run(ProductMainApplication.class, args);  
    }  
}

测试服务发现
- 这里discoveryClient和nacosServiceDiscovery效果一样

java 复制代码

@SpringBootTest  
public class DiscoveryTest {  
  
    @Autowired  
    DiscoveryClient discoveryClient;  
  
    @Autowired  
    NacosServiceDiscovery nacosServiceDiscovery;  
  
    @Test  
    void discoveryClientTest(){  
        //获取所有服务  
        for (String service : discoveryClient.getServices()) {  
            System.out.println("service = " + service);  
            //获取ip+port  
            //获取所有实例  
            List<ServiceInstance> instances = discoveryClient.getInstances(service);  
            for (ServiceInstance instance : instances) {  
                System.out.println("ip; "+instance.getHost()+"; "+"port = " + instance.getPort());  
            }  
        }  
    }  
  
    @Test  
    void nacosServiceDiscoveryTest() throws NacosException {  
        for (String service : nacosServiceDiscovery.getServices()) {  
            System.out.println("service = " + service);  
            //获取ip+port  
            try {  
                List<ServiceInstance> instances = nacosServiceDiscovery.getInstances(service);  
                for (ServiceInstance instance : instances) {  
                    System.out.println("ip; "+instance.getHost()+"; "+"port = " + instance.getPort());  
                }  
            } catch (Exception e) {  
                e.printStackTrace();  
            }  
        }  
    }  
}

3. 远程调用

配置RestTemplate

RestTemplate是Spring提供的组件，发送请求

java 复制代码

@Configuration  
 public class ProductServiceConfig {  
 	@Bean      
 	public RestTemplate restTemplate(){  
    	 return new RestTemplate();  
 	}  
 }

java 复制代码

/**  
* 远程查询商品信息  
* @param productId  
* @return  
*/  
private Product getProductFromRemote(Long productId){  
   //1. 获取商品服务所在的所有机器IP+port  
   List<ServiceInstance> instances = discoveryClient.getInstances("service-product");  
   ServiceInstance serviceInstance = instances.get(1);  
   //远程url  
   String url = "http://"+serviceInstance.getHost()+":"+serviceInstance.getPort()+"/product/"+productId;  
   log.info("url = " + url);  
   //给远程发送请求  
   Product product = restTemplate.getForObject(url, Product.class);  
   return product;  
}

4. 负载均衡

RestTemplate添加@LoadBalanced

java 复制代码

@Configuration  
public class ProductServiceConfig {  
  
    @Bean  
    @LoadBalanced    public RestTemplate restTemplate(){  
        return new RestTemplate();  
    }  
}

直接拼写
java 复制代码
```
/**  
```

基于注解的负载均衡远程查询商品信息
@param productId
@return
*/

private Product getProductFromRemoteWithLoadBalancerAnnotation(Long productId){

// 进阶 3 ：基于注解的负载均衡

String url = "http://service-product/product/"+productId;

//给远程发送请求 service-product 会被动态替换

Product product = restTemplate.getForObject(url, Product.class);

return product;

}

复制代码