Springboot使用druid配置多数据源

最近在一个需要中需要去连接其他的项目的数据库，本来想使用jbdc直接链接下的，反正就是获取数据，但是想想还是算了，正好springboot数据源配置还没有玩过，那么就正好趁这次机会学习并使用下

至于pom文件需要的依赖自然不必多说。直接从yml文件说起

spring:
  datasource:
    druid:
      master:
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://xxxx:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=false
        username: root
        password: 111111
      slave:
        url: jdbc:mysql://yyyy:3306/test?useUnicode=true&characherEncoding=utf-8&useSSL=false
        username: root
        password: 111111
        driver-class-name: com.mysql.cj.jdbc.Driver
      db-type: com.alibaba.druid.pool.DruidDataSource
      initial-size: 50
      min-idle: 50
      max-active: 100
      max-wait: 60000
      time-between-eviction-runs-millis: 60000

注意其中加粗的部分：

master表示主数据源，slave表示从数据源。公共的部分可以直接写在druid节点下面。下面需要注意的时候针对不同的数据源需要有不同的配置文件

主数据源的配置类

package com.test;

import com.alibaba.druid.pool.DruidDataSource;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
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
// 扫描 Mapper 接口并容器管理
@MapperScan(basePackages = MasterDataSourceConfig.PACKAGE, sqlSessionFactoryRef = "masterSqlSessionFactory")
public class MasterDataSourceConfig {

    //mapper接口文件存放的目录 精确到 master 目录，以便跟其他数据源隔离
    static final String PACKAGE = "com.test.mapper.master";
    static final String MAPPER_LOCATION = "classpath:mapper/master/*.xml";

    @Value("${spring.datasource.druid.master.url}")
    private String url;

    @Value("${spring.datasource.druid.master.username}")
    private String user;

    @Value("${spring.datasource.druid.master.password}")
    private String password;

    @Value("${spring.datasource.druid.master.driver-class-name}")
    private String driverClass;

    /**
     * 默认数据源
     * @return
     */
    @Bean(name="masterDataSource")
    //@Primary
    public DataSource masterDataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driverClass);
        dataSource.setUrl(url);
        dataSource.setUsername(user);
        dataSource.setPassword(password);
        return dataSource;
    }

    //@Bean(name = "masterTransactionManager")
    @Bean
    @Primary
    public DataSourceTransactionManager masterTransactionManager(@Qualifier("masterDataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

   
    @Bean
   // @Primary
    public SqlSessionFactory masterSqlSessionFactory(@Qualifer("masterDataSource") DataSource masterDataSource)
            throws Exception {
        final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
        sessionFactory.setDataSource(masterDataSource);
        sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources(MasterDataSourceConfig.MAPPER_LOCATION));
        return sessionFactory.getObject();
    }
}

从数据源的配置类

package com.test;

import com.alibaba.druid.pool.DruidDataSource;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;


@Configuration
// 扫描 Mapper 接口并容器管理
@MapperScan(basePackages = SlaveDataSourceConfig.PACKAGE, sqlSessionFactoryRef = "slaveSqlSessionFactory")
public class SlaveDataSourceConfig {

    //mapper接口文件的存放目录 精确到 slave目录，以便跟其他数据源隔离
    static final String PACKAGE = "com.test.mapper.slave";
    static final String MAPPER_LOCATION = "classpath:mapper/slave/*.xml";

    @Value("${spring.datasource.druid.slave.url}")
    private String url;

    @Value("${spring.datasource.druid.slave.username}")
    private String user;

    @Value("${spring.datasource.druid.slave.password}")
    private String password;

    @Value("${spring.datasource.druid.slave.driver-class-name}")
    private String driverClass;

   
    @Bean(name="slaveDataSource")
    public DataSource slaveDataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driverClass);
        dataSource.setUrl(url);
        dataSource.setUsername(user);
        dataSource.setPassword(password);
        return dataSource;
    }

    
    @Bean
    public DataSourceTransactionManager slaveTransactionManager(@Qualifer("slaveDataSource") DataSource slaveDataSource) {
        return new DataSourceTransactionManager(slaveDataSource);
    }

   
    @Bean
    public SqlSessionFactory slaveSqlSessionFactory(@Qualifer("slaveDataSource") DataSource slaveDataSource)
            throws Exception {
        final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
        sessionFactory.setDataSource(slaveDataSource);
        sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources(SlaveDataSourceConfig.MAPPER_LOCATION));
        return sessionFactory.getObject();
    }
}

总结：上面的配置类的位置是随便放的，方式MappSacan的位置需要注意，数据源扫描哪个mapper目录。那么该mapper目录就默认使用当前是数据源

参考链接：https://zhuanlan.zhihu.com/p/31575567