springboot项目配置多数据源

我们一起看一下多数据源的配置：(我这里配置的是主数据源是MySQL，第二数据源是Oracle)
业务场景：我们的主数据来自Oracle的数据库里面，然后我们的一些业务数据来自于MySQL数据库，Oracle数据库只提供了一个视图供我们使用。

先看一下application.yml中的配置：

#mysql配置
spring:
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/asset_inventory_prod?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true&sessionVariables=sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION'&useSSL=false&useCursorFetch=true
    username: asset_inventory_prod
    password: Asset_Inventory_Prod@123
    type: com.alibaba.druid.pool.DruidDataSource
    # 连接池配置:
    filters: stat
    minIdle: 50
    maxActive: 700
    initialSize: 10
    # 等待获取连接的时间
    maxWait: 5000
    # 连接保持空闲而不被驱逐的最小时间
    minEvictableIdleTimeMillis: 60000
    # 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
    timeBetweenEvictionRunsMillis: 30000
    # 测试连接有效性
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    keepAlive: false
    # 指定获取连接时连接校验的sql查询语句
    validationQuery: SELECT 1 FROM DUAL
    # 启用ps
    poolPreparedStatements: false
    maxPoolPreparedStatementPerConnectionSize: -1
    maxOpenPreparedStatements: -1
    # 记录被判定为异常的连接
    logAbandoned: true
#Oracle配置
oracle:
  jdbc:
    url: jdbc:oracle:thin:@127.0.0.1:8031:EAMPROD
    username: ASSET_INV
    password: asset_inv_prod
    driver: oracle.jdbc.driver.OracleDriver

接下来我们看一下需要的配置类。数据源配置类里面需要配置mysql和Oracle两种

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
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;
import org.springframework.context.annotation.Primary;

import javax.sql.DataSource;
import java.sql.SQLException;

@Slf4j
@Configuration
public class DruidDBConfig {
    @Value("${spring.datasource.url}")
    private String dbUrl;

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

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

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

    @Value("${spring.datasource.initialSize}")
    private int initialSize;

    @Value("${spring.datasource.minIdle}")
    private int minIdle;

    @Value("${spring.datasource.maxActive}")
    private int maxActive;

    @Value("${spring.datasource.maxWait}")
    private int maxWait;

    @Value("${spring.datasource.timeBetweenEvictionRunsMillis}")
    private int timeBetweenEvictionRunsMillis;

    @Value("${spring.datasource.minEvictableIdleTimeMillis}")
    private int minEvictableIdleTimeMillis;

    @Value("${spring.datasource.validationQuery}")
    private String validationQuery;

    @Value("${spring.datasource.testWhileIdle}")
    private boolean testWhileIdle;

    @Value("${spring.datasource.testOnBorrow}")
    private boolean testOnBorrow;

    @Value("${spring.datasource.testOnReturn}")
    private boolean testOnReturn;

    @Value("${spring.datasource.poolPreparedStatements}")
    private boolean poolPreparedStatements;

    @Value("${spring.datasource.maxPoolPreparedStatementPerConnectionSize}")
    private int maxPoolPreparedStatementPerConnectionSize;

    @Value("${spring.datasource.filters}")
    private String filters;


    @Value("${oracle.jdbc.url}")
    private String oracleUrl;

    @Value("${oracle.jdbc.driver}")
    private String oracleDriver;

    @Value("${oracle.jdbc.username}")
    private String oracleUserName;

    @Value("${eam.jdbc.password}")
    private String oraclePassword;


    @Bean(name = "primaryDataSource")
    @Qualifier("primaryDataSource")
    @Primary
    public DataSource dataSource() {
        DruidDataSource datasource = new DruidDataSource();

        datasource.setUrl(this.dbUrl);
        datasource.setUsername(username);
        datasource.setPassword(password);
        datasource.setDriverClassName(driverClassName);

        //configuration
        datasource.setInitialSize(initialSize);
        datasource.setMinIdle(minIdle);
        datasource.setMaxActive(maxActive);
        datasource.setMaxWait(maxWait);
        datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
        datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setValidationQuery(validationQuery);
        datasource.setTestWhileIdle(testWhileIdle);
        datasource.setTestOnBorrow(testOnBorrow);
        datasource.setTestOnReturn(testOnReturn);
        datasource.setPoolPreparedStatements(poolPreparedStatements);
        datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
        datasource.setRemoveAbandoned(true);
        try {
            datasource.setFilters(filters);
        } catch (SQLException e) {
            log.error("druid configuration initialization filter", e);
        }
        return datasource;
    }

    @Bean
    public ServletRegistrationBean druidServlet() {
        return new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
    }

    @Bean
    public FilterRegistrationBean filterRegistrationBean() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
        filterRegistrationBean.setFilter(new WebStatFilter());
        filterRegistrationBean.addUrlPatterns("/*");
        filterRegistrationBean.addInitParameter("exclusions",
                "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
        return filterRegistrationBean;
    }

    /**
     * <p>Description: [配置oracle数据源, 使用时在方法上添加注解：@Transient，即可指定使用oracle数据源]</p>
     * Created on: 2019-1-15 14:52:42
     * @return DataSource
     * @author muyuanpei
     */
    @Bean(name = "secondaryDataSource")
    @Qualifier("secondaryDataSource")
    public DataSource secondaryDataSource() {
        DruidDataSource datasource = new DruidDataSource();

        datasource.setUrl(this.oracleUrl);
        datasource.setUsername(oracleUserName);
        datasource.setPassword(oraclePassword);
        datasource.setDriverClassName(oracleDriver);

        //configuration
        datasource.setInitialSize(initialSize);
        datasource.setMinIdle(minIdle);
        datasource.setMaxActive(maxActive);
        datasource.setMaxWait(maxWait);
        datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
        datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setValidationQuery(validationQuery);
        datasource.setTestWhileIdle(testWhileIdle);
        datasource.setTestOnBorrow(testOnBorrow);
        datasource.setTestOnReturn(testOnReturn);
        datasource.setPoolPreparedStatements(poolPreparedStatements);
        datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
        datasource.setRemoveAbandoned(true);
        try {
            datasource.setFilters(filters);
        } catch (SQLException e) {
            log.error("druid configuration initialization filter", e);
        }
        return datasource;
    }
}

接下来写一下每个数据源需要的配置类:

主数据源mysql的配置类

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
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 org.springframework.transaction.PlatformTransactionManager;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.chuxin.dao.mapper", sqlSessionTemplateRef = "primarySqlSessionTemplate")
public class SqlSessionTemplate1 {


    @Bean(name = "primarySqlSessionFactory")
    @Primary
    public SqlSessionFactory primarySqlSessionFactory(@Qualifier("primaryDataSource") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/*.xml"));
        return bean.getObject();
    }

    //配置声明式事务管理器
    @Bean(name = "primaryTransactionManager")
    @Primary
    public PlatformTransactionManager primaryTransactionManager(@Qualifier("primaryDataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "primarySqlSessionTemplate")
    @Primary
    public SqlSessionTemplate primarySqlSessionTemplate(
            @Qualifier("primarySqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

第二数据源配置类：

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Qualifier;
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 org.springframework.transaction.PlatformTransactionManager;

import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.chuxin.dao.oracleMapper", sqlSessionTemplateRef = "secondarySqlSessionTemplate")
public class SqlSessionTemplate2 {

    @Bean(name = "secondarySqlSessionFactory")
    public SqlSessionFactory secondarySqlSessionFactory(@Qualifier("secondaryDataSource") DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(
                new PathMatchingResourcePatternResolver().getResources("classpath:oracleMapper/*.xml"));
        return bean.getObject();
    }

    @Bean(name = "secondaryTransactionManager")
    public PlatformTransactionManager secondaryTransactionManager(
            @Qualifier("secondaryDataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "secondarySqlSessionTemplate")
    public SqlSessionTemplate secondarySqlSessionTemplate(
            @Qualifier("secondarySqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }
}

通过如上的配置既完成了多数据源的配置。
在使用的过程中，如果像但数据源那样编码，默认使用的是主数据源，如果需要使用到第二数据源的时候，只需要在服务实现类的方法上面添加注解@Transient即可。
使用方法如下：