分布式配置nacos搭建踩坑指南(下)
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
