Spring Boot 多数据源配置

1. 项目结构

src
├── main
│   ├── java
│   │   └── org
│   │       └── songtang
│   │           └── springbootdynamic
│   │               ├── config
│   │               ├── controller
│   │               ├── entity
│   │               ├── mapper
│   │               │   ├── master
│   │               │   └── slave
│   │               └── service
│   └── resources
│       └── mapper
│           ├── master
│           └── slave
└── test

pom配置

<?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"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>3.3.2</version><relativePath/></parent><groupId>org.songtang</groupId><artifactId>springboot-dynamic</artifactId><version>0.0.1-SNAPSHOT</version><properties><java.version>17</java.version><mysql.version>8.4.0</mysql.version><mybatisplus.version>3.5.7</mybatisplus.version></properties><dependencies><!-- SpringBoot相关 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!--mybatisplus--><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-spring-boot3-starter</artifactId><version>${mybatisplus.version}</version></dependency><!--mysql 数据库相关--><dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><version>${mysql.version}</version></dependency><dependency><groupId>com.zaxxer</groupId><artifactId>HikariCP</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.34</version></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId><configuration><excludes><exclude><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></exclude></excludes></configuration></plugin></plugins><resources><resource><directory>src/main/resources</directory><includes><include>**/*.*</include></includes></resource></resources></build></project>

2. 数据源配置类 (DataSourceConfig)

此类用于配置多个数据源，并将其分别标记为 Primary 和 Secondary，以便在需要时进行区分。

package org.songtang.springbootdynamic.config;import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;
import org.apache.ibatis.session.SqlSessionFactory;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;import javax.sql.DataSource;@Configuration
public class DataSourceConfig {@Primary@Bean(name = "mainDateSource")@ConfigurationProperties(prefix = "spring.datasource.main")public DataSource mainDateSource(){return DataSourceBuilder.create().build();}@Bean(name = "targetDateSource")@ConfigurationProperties(prefix = "spring.datasource.target")public DataSource targetDateSource(){return DataSourceBuilder.create().build();}@Primary@Bean(name = "mainSessionFactory")public SqlSessionFactory mainSessionFactory(@Qualifier("mainDateSource")DataSource dataSource) throws Exception{MybatisSqlSessionFactoryBean mybatisSqlSessionFactoryBean = new MybatisSqlSessionFactoryBean();mybatisSqlSessionFactoryBean.setDataSource(dataSource);mybatisSqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/master/*.xml"));return mybatisSqlSessionFactoryBean.getObject();}@Bean(name = "targetSessionFactory")public SqlSessionFactory SessionFactory(@Qualifier("targetDateSource")DataSource dataSource) throws Exception{MybatisSqlSessionFactoryBean sqlSessionFactoryBean = new MybatisSqlSessionFactoryBean();sqlSessionFactoryBean.setDataSource(dataSource);sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/slave/*.xml"));return sqlSessionFactoryBean.getObject();}@Bean(name = "mainTransactionManager")public DataSourceTransactionManager mainTransactionManager(@Qualifier("mainDateSource") DataSource dataSource) {return new DataSourceTransactionManager(dataSource);}@Bean(name = "targetTransactionManager")public DataSourceTransactionManager targetTransactionManager(@Qualifier("targetDateSource") DataSource dataSource) {return new DataSourceTransactionManager(dataSource);}
}

3. 数据源映射配置类

MasterMapperConfig 和 SlaveMapperConfig 分别配置主数据源和从数据源的 Mapper。

主数据源配置 (MasterMapperConfig)

package org.songtang.springbootdynamic.config;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Configuration;@Configuration
@MapperScan(basePackages = "org.songtang.springbootdynamic.mapper.master", sqlSessionFactoryRef = "mainSessionFactory")
public class MasterMapperConfig {
}

从数据源配置 (SlaveMapperConfig)

package org.songtang.springbootdynamic.config;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Configuration;@Configuration
@MapperScan(basePackages = "org.songtang.springbootdynamic.mapper.slave", sqlSessionFactoryRef = "targetSessionFactory")
public class SlaveMapperConfig {
}

4. 实体类 (Member)

Member 实体类用于表示数据库中的成员数据，并与 master 和 slave 两个数据源交互。

package org.songtang.springbootdynamic.entity;import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@TableName("member")
@Data
public class Member extends BaseEntity{private String name;private String phone;private Double amount;
}

5. Mapper 接口

Mapper 接口用于定义与数据库交互的方法。

主数据源 Mapper (MasterMapper)

package org.songtang.springbootdynamic.mapper.master;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Mapper;
import org.songtang.springbootdynamic.entity.Member;@Mapper
public interface MasterMapper extends BaseMapper<Member> {// 主数据源相关操作
}

从数据源 Mapper (SlaveMapper)

package org.songtang.springbootdynamic.mapper.slave;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Mapper;
import org.songtang.springbootdynamic.entity.Member;@Mapper
public interface SlaveMapper extends BaseMapper<Member> {// 从数据源相关操作
}

6. 控制器 (Controller)

控制器类用于定义对外暴露的 API 接口，用于操作不同数据源的数据。

package org.songtang.springbootdynamic.controller;import org.songtang.springbootdynamic.entity.Member;
import org.songtang.springbootdynamic.service.YourService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;import java.util.List;@RestController
@RequestMapping("/api")
public class MultiDataSourceController {@Autowiredprivate YourService yourService;// 使用主数据源插入数据@PostMapping("/master")public void addMasterEntity(@RequestBody Member masterEntity) {yourService.addMaster(masterEntity);}// 使用从数据源插入数据@PostMapping("/slave")public void addSlaveEntity(@RequestBody Member slaveEntity) {yourService.addSlave(slaveEntity);}
}

7. 使用示例

在项目中，可以通过调用控制器的 API 来测试不同数据源的功能：

• 插入主数据源的数据: 通过 /api/master 接口插入数据
• 插入从数据源的数据: 通过 /api/slave 接口插入数据

8. application.yml 配置 

application.yml 文件中需要配置主数据源和从数据源的连接信息：

spring:datasource:main:url: jdbc:mysql://localhost:3306/masterdbusername: rootpassword: rootdriver-class-name: com.mysql.cj.jdbc.Drivertarget:url: jdbc:mysql://localhost:3306/slavedbusername: rootpassword: rootdriver-class-name: com.mysql.cj.jdbc.Driver

总结

通过以上配置，您可以在 Spring Boot 项目中成功实现多数据源的管理，分离不同的数据库操作。这样可以轻松处理不同数据源之间的事务以及数据交互，确保应用的高效性和可扩展性。