Spring boot 从1.5到2.0到2.1 版本不停的更新。多数据源配置每次都会改变。最新的spring boot2.1多数据源配置方式请参照下面介绍

环境

spring boot 2.1
druid 1.1.14
mysql

application.properties配置(参数自己补齐)

spring.datasource.primary.url=url
spring.datasource.primary.username=
spring.datasource.primary.password=
spring.datasource.primary.type=com.alibaba.druid.pool.DruidDataSource

spring.datasource.secondary.url=
spring.datasource.secondary.username=
spring.datasource.secondary.password=
spring.datasource.secondary.type=com.alibaba.druid.pool.DruidDataSource

DruidDBConfig配置

package com.conf.datasource;
import com.alibaba.druid.pool.DruidDataSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.ServletComponentScan;
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;

/**
 * @ClassName: DruidDBConfig
 * @Description:
 * @Author: zhaiwelong
 * @CreateDate: 2019/3/2 8:19
 */
@ServletComponentScan
@Configuration
public class DruidDBConfig {
    private Logger logger = LoggerFactory.getLogger(DruidDBConfig.class);

    @Value("${spring.datasource.primary.url}")
    private String dbUrl1;

    @Value("${spring.datasource.primary.username}")
    private String username1;

    @Value("${spring.datasource.primary.password}")
    private String password1;

    @Value("${spring.datasource.secondary.username}")
    private String username2;

    @Value("${spring.datasource.secondary.password}")
    private String password2;

    @Value("${spring.datasource.secondary.url}")
    private String dbUrl2;

    @Value("com.mysql.jdbc.Driver")
    private String driverClassName;

    @Value("5")
    private int initialSize;

    @Value("5")
    private int minIdle;

    @Value("20")
    private int maxActive;

    @Value("60000")
    private int maxWait;

    /**
     * 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
     */
    @Value("60000")
    private int timeBetweenEvictionRunsMillis;
    /**
     * 配置一个连接在池中最小生存的时间，单位是毫秒
     */
    @Value("300000")
    private int minEvictableIdleTimeMillis;

    @Value("SELECT 1 FROM DUAL")
    private String validationQuery;

    @Value("true")
    private boolean testWhileIdle;

    @Value("false")
    private boolean testOnBorrow;

    @Value("false")
    private boolean testOnReturn;

    /**
     * 打开PSCache，并且指定每个连接上PSCache的大小
     */
    @Value("true")
    private boolean poolPreparedStatements;

    @Value("20")
    private int maxPoolPreparedStatementPerConnectionSize;
    /**
     * 配置监控统计拦截的filters，去掉后监控界面sql无法统计，'wall'用于防火墙
     */
    @Value("stat,wall,log4j")
    private String filters;
    /**
     * 通过connectProperties属性来打开mergeSql功能；慢SQL记录
     */
    @Value("druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500")
    private String connectionProperties;

    @Bean(name = "primaryDataSource")
    @Qualifier("primaryDataSource")
    public DataSource dataSource() {
        return getDruidDataSource(username1, password1, dbUrl1);
    }

    @Bean(name = "secondaryDataSource")
    @Qualifier("secondaryDataSource")
    @Primary
    public DataSource secondaryDataSource() {
        return getDruidDataSource(username2, password2, dbUrl2);
    }

    private DruidDataSource getDruidDataSource(String username, String password, String url) {
        DruidDataSource datasource = new DruidDataSource();

        datasource.setUrl(url);
        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);
        try {
            datasource.setFilters(filters);
        } catch (SQLException e) {
            logger.error("druid configuration initialization filter : {0}", e);
        }
        datasource.setConnectionProperties(connectionProperties);

        return datasource;
    }
}

主数据源primary配置

package com.conf.datasource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateProperties;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.persistence.EntityManager;
import javax.sql.DataSource;
import java.util.Map;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactoryUser",
        transactionManagerRef = "transactionManagerUser",
        //TODO 注意修改为自己的primary的repository路径
        basePackages = {"com.zwl.repository.primary"})
public class PrimaryConfig {
    @Autowired
    @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;
    @Autowired
    private JpaProperties jpaProperties;
    @Autowired
    private HibernateProperties hibernateProperties;

    @Primary
    @Bean(name = "entityManagerUser")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return entityManagerFactoryUser(builder).getObject().createEntityManager();
    }

    @Primary
    @Bean(name = "entityManagerFactoryUser")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryUser(EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(primaryDataSource)
                //TODO 注意修改为自己的primary的model路径
                .packages("com.zwl.model.primary")
                .persistenceUnit("userPersistenceUnit")
                .properties(getVendorProperties())
                .build();
    }

    private Map<String, Object> getVendorProperties() {
        return hibernateProperties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings());
    }

    @Primary
    @Bean(name = "transactionManagerUser")
    public PlatformTransactionManager transactionManagerUser(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactoryUser(builder).getObject());
    }
}

从数据源配置

package com.conf.datasource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateProperties;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.persistence.EntityManager;
import javax.sql.DataSource;
import java.util.Map;

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactoryBusiness",
        transactionManagerRef = "transactionManagerBusiness",
        //TODO 设置repository所在位置
        basePackages = {"com.zwl.repository.secondary"})
public class SecondaryConfig {
    @Autowired
    @Qualifier("secondaryDataSource")
    private DataSource secondaryDataSource;
    @Autowired
    private JpaProperties jpaProperties;
    @Autowired
    private HibernateProperties hibernateProperties;

    @Bean(name = "entityManagerBusiness")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return entityManagerFactoryBusiness(builder).getObject().createEntityManager();
    }

    @Bean(name = "entityManagerFactoryBusiness")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryBusiness(EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(secondaryDataSource)
                .properties(getVendorProperties())
                //TODO 设置实体类所在位置
                .packages("com.zwl.model.secondary")
                .persistenceUnit("businessPersistenceUnit")
                .build();
    }

    private Map<String, Object> getVendorProperties() {
        return hibernateProperties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings());
    }

    @Bean(name = "transactionManagerBusiness")
    PlatformTransactionManager transactionManagerBusiness(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactoryBusiness(builder).getObject());
    }
}

repository和model路径展示

com
 - > zwl
 - - > model
 - - - > primary
 - - - > secondory
 
 - - > repository
 - - - > primary
 - - - > secondory

repository和model样例

repository

public interface KeywordsRepository extends PagingAndSortingRepository<Keywords,Integer> {

}

model

@Entity
public class Keywords {
    @Id
    @GeneratedValue(strategy= GenerationType.IDENTITY)
    private Integer id;
    private String keyword;

    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getKeyword() {
        return keyword;
    }
    public void setKeyword(String keyword) {
        this.keyword = keyword;
    }
    public Keywords() {
    }
}

收工总结

1.pom项目搭建
2.application.properties文件或者yml参数编写
3.DruidDBConfig数据源配置
4.PrimaryConfig主数据源配置
5.SecondaryConfig从数据源配置
6.model及repository编写
7.测试收工

题外话（旧版本配置）

Spring Boot 1.5.x
private Map<String, String> getVendorProperties() {
return jpaProperties.getHibernateProperties(userDataSource);
}
Spring Boot 2.0.x
private Map<String, Object> getVendorProperties() {
return jpaProperties.getHibernateProperties(new HibernateSettings());
}
2.1版本参照上文