Spring Boot 3 整合 Mybatis-Plus 动态数据源实现多数据源切换

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>dynamic-datasource-spring-boot3-starter</artifactId>
    <version>4.2.0</version>
</dependency>

<dependency>
  <groupId>com.baomidou</groupId>
  <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
  <version>4.2.0</version>
</dependency>

spring:
  datasource:
    dynamic:
      primary: master #设置默认的数据源或者数据源组,默认值即为 master
      strict: false # 设置严格模式，当数据源找不到时，是否抛出异常，默认为false不抛出
      datasource:
        master: # 主库
          type: com.alibaba.druid.pool.DruidDataSource
          driver-class-name: com.mysql.cj.jdbc.Driver # 3.2.0开始支持SPI可省略此配置
          url: jdbc:mysql://www.youlai.tech:3306/youlai_boot?zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai&autoReconnect=true&allowMultiQueries=true
          username: youlai
          password: 123456
        slave: # 从库
          type: com.alibaba.druid.pool.DruidDataSource
          driver-class-name: com.mysql.cj.jdbc.Driver
          url: jdbc:mysql://localhost:3306/youlai_boot?zeroDateTimeBehavior=convertToNull&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai&autoReconnect=true&allowMultiQueries=true
          username: root
          password: 123456

/**
 * 主库查询
 */
@DS("master")
@Select("select * from sys_user where id = #{userId}")
SysUser getUserFromMaster(Long userId);
/**
 * 从库查询
 */
@DS("slave")
@Select("select * from sys_user where id = #{userId}")
SysUser getUserFromSlave(Long userId);

package com.youlai.system.mapper;
import com.youlai.system.model.entity.SysUser;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
@SpringBootTest
@Slf4j
class SysUserMapperTest {
    @Autowired
    private SysUserMapper userMapper;
    private final Long userId = 1L;
    /**
     * 测试注解方式切换数据源
     */
    @Test
    void testSwitchDataSourceByAnnotation() {
        SysUser masterUser = userMapper.getUserFromMaster(userId);
        log.info("用户ID：{} 主库姓名：{}", userId, masterUser.getNickname());
        SysUser slaveUser = userMapper.getUserFromSlave(userId);
        log.info("用户ID：{} 从库姓名：{}", userId, slaveUser.getNickname());
    }
}

    /**
     * 测试手动方式切换数据源
     */
    @Test
    void testDataSourceSwitchManually() {
        DynamicDataSourceContextHolder.push("master");
        SysUser masterUser = userMapper.selectById(userId);
        log.info("手动切换：主库姓名：{}", masterUser.getNickname());
        DynamicDataSourceContextHolder.poll();
        DynamicDataSourceContextHolder.push("slave");
        SysUser slaveUser = userMapper.selectById(userId);
        log.info("手动切换：从库姓名：{}",  slaveUser.getNickname());
        DynamicDataSourceContextHolder.poll();
    }