Spring cloud Nacos服务注册与发现

1月18日，北京，聊聊2025如何加入技术开发？

1、Nacos安装
官方教程：https://nacos.io/zh-cn/docs/quick-start.html
GitHub:https://github.com/alibaba/nacos
下载地址：https://github.com/alibaba/nacos/releases

安装

unzip nacos-server-$version.zip 或者 tar -xvf nacos-server-$version.tar.gz
cd nacos/bin

启动命令
Linux/Unix/Mac
启动命令(standalone代表着单机模式运行，非集群模式):

sh startup.sh -m standalone

如果您使用的是ubuntu系统，或者运行脚本报错提示[[符号找不到，可尝试如下运行：

bash startup.sh -m standalone

Windows
启动命令(standalone代表着单机模式运行，非集群模式):

startup.cmd -m standalone

2、服务注册
创建工程spring-cloud-alibaba-nacos-provider
pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com.penngo.cloud</groupId>
	<artifactId>spring-cloud-alibaba-nacos-provider</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>spring-cloud-alibaba-nacos-provider</name>
	<description>https://my.oschina.net/penngo</description>

	<properties>
		<java.version>1.8</java.version>
		<spring-boot.version>2.4.13</spring-boot.version>
		<spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>com.alibaba.cloud</groupId>
			<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
		</dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>com.alibaba.cloud</groupId>
				<artifactId>spring-cloud-alibaba-dependencies</artifactId>
				<version>${spring-cloud-alibaba.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
			<dependency>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-dependencies</artifactId>
				<version>${spring-boot.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

application.properties

spring.application.name=my-provider
server.port=8080
spring.cloud.nacos.discovery.server-addr=localhost:8848

NacosProvider.java

package com.penngo.cloud;

import javax.servlet.http.HttpServletRequest;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
public class NacosProvider {
    public static void main(String[] args) {
        SpringApplication.run(NacosProvider.class, args);
    }
    @RestController
    class EchoController {

        @GetMapping("/echo")
        public String echo(HttpServletRequest request) {
            return "echo: " + request.getParameter("name");
        }
    }
}

3、服务发现

创建工程spring-cloud-alibaba-nacos-consumer

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com.penngo.cloud</groupId>
	<artifactId>spring-cloud-alibaba-nacos-consumer</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>spring-cloud-alibaba-nacos-consumer</name>
	<description>https://my.oschina.net/penngo</description>

	<properties>
		<java.version>1.8</java.version>
		<spring-cloud-alibaba.version>2021.1</spring-cloud-alibaba.version>
		<spring-boot.version>2.4.13</spring-boot.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>com.alibaba.cloud</groupId>
			<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
		</dependency>
        <dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>com.alibaba.cloud</groupId>
				<artifactId>spring-cloud-alibaba-dependencies</artifactId>
				<version>${spring-cloud-alibaba.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
			<dependency>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-dependencies</artifactId>
				<version>${spring-boot.version}</version>
				<type>pom</type>
				<scope>import</scope>
			</dependency>
		</dependencies>
	</dependencyManagement>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                </configuration>
            </plugin>
        </plugins>
	</build>

</project>

application.properties

spring.application.name=nacos-consumer
server.port=8081
spring.cloud.nacos.discovery.server-addr=localhost:8848

NacosConsumer.java

package com.penngo.cloud;

import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@EnableDiscoveryClient(autoRegister = false)
public class NacosConsumer {

    public static void main(String[] args) {
        SpringApplication.run(NacosConsumer.class, args);
    }

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

    @RestController
    class HelloController {
        @Autowired
        private DiscoveryClient discoveryClient;
        @Autowired
        private RestTemplate restTemplate;
        private String serviceName = "my-provider";
        @GetMapping("/info")
        public String info() {
            List<ServiceInstance> serviceInstances = discoveryClient.getInstances(serviceName);
            StringBuilder sb = new StringBuilder();
            sb.append("All services: " + discoveryClient.getServices() + "<br/>");
            sb.append("my-provider instance list: <br/>");
            serviceInstances.forEach(instance -> {
                sb.append("[ serviceId: " + instance.getServiceId() +
                    ", host: " + instance.getHost() +
                    ", port: " + instance.getPort() + " ]");
                sb.append("<br/>");
            });
            return sb.toString();
        }

        @GetMapping("/hello")
        public String hello() {
            List<ServiceInstance> serviceInstances = discoveryClient.getInstances(serviceName);
            ServiceInstance serviceInstance = serviceInstances.stream()
                .findAny().orElseThrow(() ->
                    new IllegalStateException("no " + serviceName + " instance available"));
            return restTemplate.getForObject(
                "http://" + serviceInstance.getHost() + ":" + serviceInstance.getPort() +
                    "/echo?name=nacos", String.class);
        }
    }
}

4、浏览器访问

源码下载