上一篇介绍了在配置nacos中的碰到的坑，这一篇介绍一下如何正确进行nacos的环境搭建和配置，所以本文分为两部分，第一部分为环境搭建，介绍如何安装和运行。第二部分为alibaba Sprint Boot配置，介绍如何正确配置。
注意：本文基于nacos 2.2.0,alibaba Spring Boot 2.6.11，eclipse,操作系统为windows.
一.环境搭建
1.下载nacos
在github上下载nacos的windows安装文件,网址为：https://github.com/alibaba/nacos/releases，这里选择2.2.0下载,选择.zip格式的即可，入下所示：
2.运行nacos
解压下载回来的zip文件至D盘，进入bin文件夹，运行：.startup.cmd -m standalone 启动nacos,如果看到" Nacos started successfully in stand alone mode. use embedded storage",恭喜！运行成功！如下所示：
3.登录配置界面：
在浏览器中访问：http://localhost:8848/nacos/，用户名和密码都是nacos,即可进入后台配置页面，如下所示：
第二部分 Spring Boot配置
1.下载alibaba Spring Boot脚手架
访问https://start.aliyun.com/bootstrap.html，Group输入：com.alibaba.cloud,Artifact:nacos-config-sample,组件选择：Nacos Configuration,Spring Web,Spring Boot Actuator,同时需要引入Spring Cloud下的Cloud Bootstrap。这个在阿里巴巴出版的电子书<<Spring Cloud alibaba 从入门到实战>>中没有介绍。如果没有引入Cloud Bootstrap，在eclipse中运行后必报错,截图如下：
下面是完整的pom.xml文件：
<?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> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.6.11</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.alibaba.cloud</groupId> <artifactId>nacos-config-sample</artifactId> <version>0.0.1-SNAPSHOT</version> <name>nacos-config-sample</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> <spring-cloud-alibaba.version>2021.0.4.0</spring-cloud-alibaba.version> <spring-cloud.version>2021.0.4</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-bootstrap</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-web</artifactId> </dependency> <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-alibaba-dependencies</artifactId> <version>${spring-cloud-alibaba.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.8.1</version> <configuration> <source>1.8</source> <target>1.8</target> <encoding>UTF-8</encoding> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
2.配置namespace
访问http://localhost:8848/nacos/，在后台新建一个名为testnamespace的namespace,记住它的id:bd1caf11-e4f1-4dd0-9a4b-2c32041c64e2，待会在spring boot配置中要用到，如下所示：
3.配置Properties
在配置管理中，我们选择刚才新建的testnamespace命名空间,在这个下面创建配置，新增一个data id为：nacos-config-sample.properties 的配置，配置格式选择properties.注意,data id的格式为{spring boot 应用名}.properties,两边必须要一致，否则报错！如下所示：
4.配置Spring Boot:
1)配置bootstrap.properties
spring.cloud.nacos.config.username=nacos spring.cloud.nacos.config.password=nacos spring.cloud.nacos.config.contextPath=/nacos spring.cloud.nacos.config.server-addr=localhost:8848 spring.cloud.nacos.config.namespace=bd1caf11-e4f1-4dd0-9a4b-2c32041c64e2 spring.cloud.nacos.config.extension-configs[0].data-id=nacos-config-sample.properties spring.cloud.nacos.config.extension-configs[0].refresh=true
注意spring.cloud.nacos.config.namespace=bd1caf11-e4f1-4dd0-9a4b-2c32041c64e2，这个namespace就是上面新建命名空间的id.
2)配置application.properties
spring.application.name=nacos-config-sample server.port=8080 management.server.port=8081 management.endpoints.jmx.exposure.include=* management.endpoints.web.exposure.include=* management.endpoint.health.show-details=always
3)新建实体类
package com.alibaba.cloud.nacosconfigsample; import com.alibaba.nacos.api.config.annotation.*; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.cloud.context.config.annotation.RefreshScope; import org.springframework.cloud.context.scope.*; @RefreshScope //@ConfigurationProperties(prefix="user") public class User { private String name; private int age; public String getName() { return name; } public void setName(String name) { this.name=name; } public int getAge() { return this.age; } public void setAge(int age) { this.age=age; } }
4）Spring boot启动类
package com.alibaba.cloud.nacosconfigsample; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.context.properties.EnableConfigurationProperties; import org.springframework.cloud.context.config.annotation.RefreshScope; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.boot.autoconfigure.SpringBootApplication; import com.alibaba.nacos.api.config.annotation.*; import org.springframework.cloud.context.config.annotation.RefreshScope; import javax.annotation.*; @RestController @SpringBootApplication @RefreshScope //@EnableConfigurationProperties(User.class) public class NacosConfigSampleApplication { @Value("${user.name}") //import org.springframework.cloud.context.config.annotation.RefreshScope; private String userName; @Value("${user.age}") private int age; @PostConstruct public void init() { System.out.printf("[init] user age is: %s",userName); } // @Autowired // private User user; @RequestMapping("/user") public String user() { return "user :"+userName; //return user.getName(); } @PreDestroy public void destroy() { System.out.printf("[destroy] user age : %s ",userName); } public static void main(String[] args) { SpringApplication.run(NacosConfigSampleApplication.class, args); } }
5)修改配置中的user.的name，在spring boot中观察是否更新
