SpringBoot配置多数据源

在工作中，业务的发展或业务数据隔离的场景下，通常需要一个项目中引入多个数据源，但SpringBoot默认的自动化配置是单数据源的，在这里记录一个通过Spring分包的方式进行的多数据源配置

1.引入以下依赖

        org.springframework.boot
        spring-boot-starter-parent
        2.3.0.RELEASE
         
    

    
    
            org.springframework.boot
            spring-boot-starter-web
        

        
            org.springframework.boot
            spring-boot-starter-test
            test
        
       
        
        
            com.baomidou
            mybatis-plus-boot-starter
            3.3.2
        
        
        
        
            mysql
            mysql-connector-java
            runtime
        
        
        
            com.alibaba
            druid-spring-boot-starter
            1.1.10
        
        
        
            com.alibaba
            fastjson
            1.2.68
        
        
        
            org.projectlombok
            lombok
        
        
        
            org.springframework.boot
            spring-boot-starter-thymeleaf
        
    

    
        
            
                org.springframework.boot
                spring-boot-maven-plugin
            
        
    

2.application.yml修改

server:
  port: 8751
spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    druid:
      initial-size: 5
      min-idle: 5
      max-active: 100
      max-wait: 60000
      im:
        url: jdbc:mysql://192.168.16.112:3306/erlinyou_im?autoconnection&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull
        username: root
        password: 12345678
        driver-class-name: com.mysql.cj.jdbc.Driver
      user:
        url: jdbc:mysql://192.168.16.114:3306/etravel?autoconnection&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull
        username: root
        password: 12345678
        driver-class-name: com.mysql.cj.jdbc.Driver

mybatis-plus:
  type-aliases-package: com.erlinyou.im.push.model
  mapper-locations: classpath:mapper/*.xml
logging:
  level:
    com.erlinyou.im.push.mapper: debug
    root: info
  file:
    name: log/sso.log

application定义了两个数据源，其他为mybaits-plus和spring的基本配置

3.启动类注解配置

@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class, DataSourceTransactionManagerAutoConfiguration.class, MybatisPlusAutoConfiguration.class})

/**
 * 使用exclude = {DataSourceAutoConfiguration.class}
 * 禁用springboot默认加载的application.properties单数据源配置
 * 关闭springBoot关于mybatisPlus的一些自动注入
 */

4.配置druid

import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class DruidConfig {

    @Bean
    public ServletRegistrationBean druidServlet () {
        ServletRegistrationBean servletRegistrationBean
                = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
        servletRegistrationBean.addInitParameter("loginUsername", "admin");
        servletRegistrationBean.addInitParameter("loginPassword", "admin");
        servletRegistrationBean.addInitParameter("resetEnable", "false");

        return servletRegistrationBean;
    }

    @Bean
    public FilterRegistrationBean filterRegistrationBean() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
        filterRegistrationBean.addUrlPatterns("/*");
        filterRegistrationBean.addInitParameter("exclusions", "*.js,*.css, /druid/*");

        return filterRegistrationBean;
    }
}

5.配置包扫描配置数据源

@Configuration
@MapperScan(basePackages = "com.xxx.im.push.mapper.im",sqlSessionFactoryRef = "imSqlSessionFactory")
public class ImDataSourceConfig {


    @Bean(name = "imDataSource")
    @ConfigurationProperties("spring.datasource.druid.im")
    public DataSource masterDataSource(){
//        return DataSourceBuilder.create().build();
        return new DruidDataSource();
    }

    @Bean(name = "imSqlSessionFactory")
    public SqlSessionFactory sqlSessionFactory(@Qualifier("imDataSource") DataSource dataSource) throws Exception {
        MybatisSqlSessionFactoryBean sessionFactoryBean = new MybatisSqlSessionFactoryBean();
        sessionFactoryBean.setDataSource(dataSource);

        return sessionFactoryBean.getObject();
    }
}

@ConfigurationProperties注解用于加载自定义的外部化配置

DataSourceBuilder.create().build();为hikari，也是SpringBoot默认的数据源，hikari也非常强大

new DruidDataSource();是druid数据源，这里采用druid数据源

以下为另一个数据源配置，同理

import com.alibaba.druid.pool.DruidDataSource;
import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.annotation.MapperScan;
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 javax.sql.DataSource;


@Configuration
@MapperScan(basePackages = "com.xxx.im.push.mapper.user",sqlSessionFactoryRef = "userSqlSessionFactory")
public class UserDataSourceConfig {

    @Primary
    @Bean(name = "userDataSource")
    @ConfigurationProperties("spring.datasource.druid.user")
    public DataSource masterDataSource(){
//        return DataSourceBuilder.create().build();
        return new DruidDataSource();
    }

    @Bean(name = "userSqlSessionFactory")
    public SqlSessionFactory sqlSessionFactory(@Qualifier("userDataSource") DataSource dataSource) throws Exception {
        MybatisSqlSessionFactoryBean sessionFactoryBean = new MybatisSqlSessionFactoryBean();
        sessionFactoryBean.setDataSource(dataSource);
        return sessionFactoryBean.getObject();
    }
}

总结一下

这种多数据源配置是通过mybaits动态扫描包的方式进行数据的切换，目前比较主流的还有通过AOP+ThreadLocal扫描注解的方式利用ThreadLocal对当前线程的数据源进行动态切换到达配置多数据源的目的，以及dynamic-datasource-spring-boot-starter 的方式，根据合适的业务场景来使用可以达到更好的效果，通过mybaits切换数据比较简单方便可以满足大部分对多数据源配置的业务场景