Springboot+JPA(Postgresql / Mysql)多数据源配置

开始只使用一个Postgresql数据库，现在由于用到redmine自带的mysql数据源，需要使用多数据源。整理了一下配置方法。目录结构如下：

首先需要修改yml文件

server:
  servlet:
    context-path: /api
  port: 8080

spring:
  jpa:
    hibernate:
      ddl-auto: none
    show-sql: true
    properties:
      hibernate:
        #注意这里两个数据库有对应的方言配置
        primary-dialect: org.hibernate.dialect.PostgreSQLDialect
        secondary-dialect: org.hibernate.dialect.MySQL5Dialect
        temp:
          use_jdbc_metadata_defaults: false
  #primary注意驱动不要写错了
  primary:
    datasource:
      driver-class-name: org.postgresql.Driver
      jdbc-url: jdbc:postgresql://127.0.0.1:5432/xxx
      username: xxx
      password: xxx
      type: com.alibaba.druid.pool.DruidDataSource
      initialSize: 5
      minIdle: 5
      maxActive: 20
      maxWait: 10000
      timeBetweenEvictionRunMillis: 60000
      minEvictableIdleTimeMillis: 30000
      validationQuery: SELECT 'x'
      testWhileIdle: true
      testOnBorrow: true
      testOnReturn: false
      poolPreparedStatements: true
      maxPoolPreparedStatementPerConnectionSize: 10
      filters: stat
  #secondary
  secondary:
    datasource:
      driver-class-name: com.mysql.cj.jdbc.Driver
      jdbc-url: jdbc:mysql://127.0.0.1:3307/bitnami_redmine?characterEncoding=utf8&useSSL=false&serverTimezone=Asia/Shanghai&useLegacyDatetimeCode=false
      username: xxx
      password: xxx
      type: com.alibaba.druid.pool.DruidDataSource
      initialSize: 5
      minIdle: 5
      maxActive: 20
      maxWait: 10000
      timeBetweenEvictionRunMillis: 60000
      minEvictableIdleTimeMillis: 30000
      validationQuery: SELECT 'x'
      testWhileIdle: true
      testOnBorrow: true
      testOnReturn: false
      poolPreparedStatements: true
      maxPoolPreparedStatementPerConnectionSize: 10
      filters: stat



  main:
    allow:
      bean:
        definition:
          overriding: true

下面是几个配置文件，配置文件和启动类放在同一目录下

DataSourceConfig 文件：不需要改动

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;


/**
 * 数据源的配置
 */
@Configuration
public class DataSourceConfig {

    @Bean(name = "primaryDataSource")
    @Qualifier("primaryDataSource")
    @ConfigurationProperties(prefix = "spring.primary.datasource")
    @Primary
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "secondaryDataSource")
    @Qualifier("secondaryDataSource")
    @ConfigurationProperties(prefix = "spring.secondary.datasource")
    public DataSource secondaryDataSource() {
        return DataSourceBuilder.create().build();
    }

}

PrimaryConfig 文件

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
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.HashMap;
import java.util.Map;

/**
 * 数据源一
 */
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactoryPrimary",
        transactionManagerRef = "transactionManagerPrimary",
        basePackages = {
                "com.xxx.xx.xx.repository"

        }) //设置Repository所在位置

public class PrimaryConfig {


    @Autowired
    @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;

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

    @Primary
    @Bean(name = "entityManagerFactoryPrimary")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder) {

        return builder
                .dataSource(primaryDataSource)
                .properties(getVendorProperties())
                .packages(
                        "com.xxxx.xx.xx.domain"

                ) //设置实体类所在位置
                .persistenceUnit("primaryPersistenceUnit")
                .build();
    }


    @Autowired
    private JpaProperties jpaProperties;
    @Autowired
    private HibernateProperties hibernateProperties;
    private Map getVendorProperties() {

        return hibernateProperties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings());
    }
    @Primary
    @Bean(name = "transactionManagerPrimary")
    public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
    }
}

SecondaryConfig 文件

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;

/**
 * 数据源二
 */
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactorySecondary",
        transactionManagerRef = "transactionManagerSecondary",
        basePackages = {
                "com.xxxx.xx.xx.readmine.repository"
        }) //设置Repository所在位置,两个数据库对应的repository和实体类需要不同的路径
public class SecondaryConfig {

    @Autowired
    @Qualifier("secondaryDataSource")
    private DataSource secondaryDataSource;

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

    @Bean(name = "entityManagerFactorySecondary")
    public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary(EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(secondaryDataSource)
                .properties(getVendorProperties())
                .packages(
                        "com.xxxx.xx.xx.readmine.domain"
                ) //设置实体类所在位置
                .persistenceUnit("secondaryPersistenceUnit")
                .build();
    }

    @Autowired
    private JpaProperties jpaProperties;

    @Autowired
    private HibernateProperties hibernateProperties;
    private Map getVendorProperties() {
        return hibernateProperties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings());
    }

    //用来作为数据库事务回滚的限定词
    //@Transactional(rollbackFor = OAPMException.class, value = "transactionManagerSecondary")
    //事务管理器
    @Bean(name = "transactionManagerSecondary")
    PlatformTransactionManager transactionManagerSecondary(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
    }
}

在使用@Transactional 管理数据库回滚的时候需要注意

多数据源@Transactional 需要指定数据源 ，否则无法回滚。

value需要填写一个数据源配置里面的一个参数,value的值就是SecondaryConfig 文件中内容

@Transactional(rollbackFor = Exception.class,value = "transactionManagerSecondary")