druid多数据源+mybatis-plus的dynamic【一个简单例子】

主要利用dynamic来实现动态数据源

1 pom文件加依赖

<!--版本号-->
<properties>
    <mybatisplus.boot.version>3.1.0</mybatisplus.boot.version>
    <dynamic.datasource.boot.version>2.5.4</dynamic.datasource.boot.version>
    <druid-spring-boot.version>1.1.10</druid-spring-boot.version>
</properties>

<!-- 德鲁伊连接池 -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>${druid-spring-boot.version}</version>
</dependency>

<!--苞米豆的动态数据源-->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>dynamic-datasource-spring-boot-starter</artifactId>
    <version>${dynamic.datasource.boot.version}</version>
</dependency>
        
<!--苞米豆的代码精简插件-->
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>${mybatisplus.boot.version}</version>
</dependency>

2 配置yml信息

dynamic包里面也有德鲁伊的配置信息，但是不是很多，主要是为了实现动态路由

连接池的信息一定要配置化再dynamic下面的一层，不然是不会生效的

数据源监控建议配置在datasource下面

server:
  port: 1234


spring:
  # 为了某些版本的springboot  @SpringBootApplication(exclude= {DataSourceAutoConfiguration.class}) 无法生效
  autoconfigure:
    exclude: com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceAutoConfigure
  datasource:
    dynamic:
      primary: db1 # 多数据源的情况下，主数据源（默认值master），可以自定义
      datasource:
        db1:
          url: jdbc:mysql://127.0.0.1:3306/photo?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=false&serverTimezone=GMT%2B8&serverTimezone=Asia/Shanghai
          username: root
          password: 123456
          driverClassName:  com.mysql.cj.jdbc.Driver
        db2:
          url: jdbc:mysql://127.0.0.1:3306/photo2?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=false&serverTimezone=GMT%2B8&serverTimezone=Asia/Shanghai
          username: root
          password: 123456
          driverClassName:  com.mysql.cj.jdbc.Driver
      # 公共参数配置(连接池)
      druid:
        initial-size: 10
        max-active: 100
        min-idle: 10
        max-wait: 60000
        pool-prepared-statements: true
        max-pool-prepared-statement-per-connection-size: 20
        time-between-eviction-runs-millis: 60000
        min-evictable-idle-time-millis: 300000
        test-while-idle: true
        test-on-borrow: false
        test-on-return: false
    # 数据源监控配置
    druid:
      stat-view-servlet:
        enabled: true
        url-pattern: /druid/*
        login-username: druid
        login-password: 123456

也可以看一下监控信息http://127.0.0.1:1234/druid/datasource.html

3 配置数据库

就很简单的写了几个字段
db1

db2

4 配置代码

启动项上加上下面这个，就是去掉springboot自动配置数据源
@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})

启动项目后默认是 primary指定的数据源db1

如果需要使用第二个数据库，只需要在mapper或者service类上配置@DS("db2")即可

mapper文件

@DS("db2")
public interface Photo2Mapper extends BaseMapper<PhotoEntity> {
    PhotoEntity selectOneById(String id);
}

xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.lh.my.project.mapper.Photo2Mapper">

    <select id="selectOneById" resultType="cn.lh.my.project.entity.PhotoEntity">
        select id, cert_name, trade_id from batch_photo_202102 where id = #{id}
    </select>
</mapper>

service接口

@DS("db2")
public interface Photo2Service extends IService<PhotoEntity> {

    PhotoEntity selectOneById(String id);

}

impl文件

@Service
public class Photo2ServiceImpl extends ServiceImpl<Photo2Mapper, PhotoEntity>  implements Photo2Service {

    @Resource
    private Photo2Mapper photo2Mapper;

    @Override
    public PhotoEntity selectOneById(String id) {
        return photo2Mapper.selectOneById(id);
    }
}

test类测试一下

	@Autowired
    private PhotoService photoService;
    @Resource
    private PhotoMapper photoMapper;
    @Resource
    private Photo2Mapper photo2Mapper;
    @Autowired
    private Photo2Service photo2Service;
    
@Test
public void ds() {
	PhotoEntity photoEntity = photoMapper.selectById("333");
    log.info("数据库db1============={}", photoEntity.toString());

    PhotoEntity mapper = photo2Mapper.selectById("333");
    log.info("mapper============={}", mapper.toString());
    PhotoEntity plusMapper = photo2Mapper.selectOne(new QueryWrapper<PhotoEntity>().lambda().eq(PhotoEntity::getId, "333"));
    log.info("plusMapper============={}", plusMapper.toString());


    PhotoEntity service = photo2Service.selectOneById("333");
    log.info("service============={}", service.toString());
    PhotoEntity plusService = photo2Service.getOne(new QueryWrapper<PhotoEntity>().lambda().eq(PhotoEntity::getId, "333"));
    log.info("plusService============={}", plusService.toString());
}