Spring Boot集成nacos快速入门demo

一、nacos介绍

Nacos 致力于帮助您发现、配置和管理微服务。Nacos 提供了一组简单易用的特性集，帮助您快速实现动态服务发现、服务配置、服务元数据及流量管理。

二、环境搭建

# docker-compose参考：https://github.com/nacos-group/nacos-docker/blob/master/example/standalone-mysql-5.7.yaml
# Nacos文档：https://nacos.io/zh-cn/index.html
version: '3'

# 网桥 -> 方便相互通讯
networks:
  nacos:
    driver: bridge

services:
  nacos:
    image: registry.cn-hangzhou.aliyuncs.com/zhengqing/nacos-server:2.2.0    # 原镜像`nacos/nacos-server:2.2.0`
    container_name: nacos_server                                 # 容器名为'nacos_server'
    restart: unless-stopped                                              # 指定容器退出后的重启策略为始终重启，但是不考虑在Docker守护进程启动时就已经停止了的容器
    volumes:                                                     # 数据卷挂载路径设置,将本机目录映射到容器目录
      - "./nacos/logs:/home/nacos/logs"
    environment:                        # 设置环境变量,相当于docker run命令中的-e
      - PREFER_HOST_MODE=hostname                 # 如果支持主机名可以使用hostname,否则使用ip，默认也是ip
      - MODE=standalone                           # 单机模式启动
      - SPRING_DATASOURCE_PLATFORM=mysql          # 数据源平台 仅支持mysql或不保存empty
      # TODO 修改mysql连接信息
      - MYSQL_SERVICE_HOST=10.11.68.77           # 注：这里不能为`127.0.0.1`或`localhost`方式！！！
      - MYSQL_SERVICE_DB_NAME=nacos_config        # 所需sql脚本位于 `nacos/nacos-mysql.sql`
      - MYSQL_SERVICE_PORT=3306
      - MYSQL_SERVICE_USER=root
      - MYSQL_SERVICE_PASSWORD=root
      # TODO 修改JVM调优参数
      - JVM_XMS=128m   #-Xms default :2g
      - JVM_XMX=128m   #-Xmx default :2g
      - JVM_XMN=64m    #-Xmn default :1g
      - JVM_MS=32m     #-XX:MetaspaceSize default :128m
      - JVM_MMS=32m    #-XX:MaxMetaspaceSize default :320m
    ports:
      - "8848:8848"
    depends_on:
      - mysql
    networks:
      - nacos
    mem_limit: 1000m   # 最大使用内存
  mysql:
    image: registry.cn-hangzhou.aliyuncs.com/zhengqing/mysql:5.7
    container_name: nacos-mysql
    restart: unless-stopped
    volumes:
      - "./nacos/mysql5.7/my.cnf:/etc/mysql/my.cnf"
      - "./nacos/mysql5.7/data:/var/lib/mysql"
      - "./nacos/mysql5.7/log/mysql/error.log:/var/log/mysql/error.log"
    environment:
      TZ: Asia/Shanghai
      LANG: en_US.UTF-8
      MYSQL_ROOT_PASSWORD: root         # 设置root用户密码
      MYSQL_DATABASE: nacos_config           # 初始化数据库
    ports:
      - "3306:3306"
    networks:
      - nacos

启动环境

# tips: 先修改配置与导入`nacos/nacos-mysql.sql`
docker-compose -f docker-compose.yml -p nacos up -d

新增配置dataId 为test

server.port=8086
useLocalCache=false

三、代码工程

maven依赖

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>springboot-demo</artifactId>
        <groupId>com.et</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>nacos</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <!-- 2.1.2版本以上支持纯净版客户端 -->
        <nacos.version>0.2.7</nacos.version>

    </properties>
    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.boot</groupId>
            <artifactId>nacos-config-spring-boot-starter</artifactId>
            <version>${nacos.version}</version>
        </dependency>



    </dependencies>
</project>

controller

package com.et.nacos.controller;

import com.alibaba.nacos.api.config.annotation.NacosValue;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import static org.springframework.web.bind.annotation.RequestMethod.GET;

@Controller
@RequestMapping("config")
public class ConfigController {

    @NacosValue(value = "${useLocalCache:false}", autoRefreshed = true)
    private boolean useLocalCache;

    @RequestMapping(value = "/get", method = GET)
    @ResponseBody
    public boolean get() {
        return useLocalCache;
    }
}

配置文件

nacos:
  config:
    server-addr: 127.0.0.1:8848

启动类

package com.et.nacos;

import com.alibaba.nacos.spring.context.annotation.config.NacosPropertySource;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@NacosPropertySource(dataId = "test", autoRefreshed = true)
public class DemoApplication {

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

代码仓库

• https://github.com/Harries/springboot-demo

四、测试

1. 访问 http://localhost:8080/config/get，返回内容是 false。
2. 通过nacos控制台修改配置：dataId 为example，内容为useLocalCache=true
3. 再次访问 http://localhost:8080/config/get，此时返回内容为true，说明程序中的useLocalCache值已经被动态更新了。

五、引用

• https://raw.githubusercontent.com/alibaba/nacos/develop/distribution/conf/mysql-schema.sql
• https://nacos.io/docs/v2/ecology/use-nacos-with-spring-boot/
• http://www.liuhaihua.cn/archives/710246.html