SpringDataJPA配置多个存储单元

场景

在使用Spring Data JPA的服务中, 需要同时连接自己的数据库进行增删改查, 也需要连接一个外部提供的数据库查询数据. 因此需要维护两套数据库配置.

实现思路

首先使用JPA一般都需要domain实体和repository. 规划为:

• 主数据库的实体都放到统一包domain下, repository放repository下
• 第二套数据库的实体都放到统一包share.domain下, repository放share.repository下

然后通过配置两套持久化单元,并分别指定扫描的包,完成两套数据库配置. 然后就可以通过调用repository分别实现对两套数据库的调用了.

主数据库的结构

./example/domain/User.java
./example/repository/UserRepository.java

第二套数据库结构

./example/share/domain/School.java
./example/share/repository/SchoolRepository.java

具体实现

1. 主数据库配置

主数据库配置

import com.zaxxer.hikari.HikariDataSource;
import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
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.EnableJpaAuditing;
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.EntityManagerFactory;
import javax.sql.DataSource;

@Configuration
@EnableJpaAuditing
@EnableTransactionManagement
// 指定扫描的仓库目录
@EnableJpaRepositories(basePackages = {"example.repository"}, entityManagerFactoryRef = "entityManagerFactory", transactionManagerRef = "transactionManager")
public class DatabaseConfiguration {

    @Bean(name = "primaryDataSourceProperties")
    @ConfigurationProperties("spring.datasource")
    @Primary
    public DataSourceProperties dataSourceProperties() {
        return new DataSourceProperties();
    }

    @Primary
    @Bean(name = "dataSource")
    @ConfigurationProperties("spring.datasource.hikari")
    public HikariDataSource firstDataSource(DataSourceProperties firstDataSourceProperties) {
        return firstDataSourceProperties.initializeDataSourceBuilder().type(HikariDataSource.class).build();
    }

    @Primary
    @Bean(name = "entityManagerFactory")
    public LocalContainerEntityManagerFactoryBean
    entityManagerFactory(
            EntityManagerFactoryBuilder builder,
            DataSource dataSource
    ) {
        return builder
                .dataSource(dataSource)
                // 指定扫描包
                .packages("example.domain")
                .persistenceUnit("primary-domain")
                .build();
    }

    @Primary
    @Bean(name = "transactionManager")
    public PlatformTransactionManager transactionManager(
            EntityManagerFactory
                    entityManagerFactory
    ) {
        return new JpaTransactionManager(entityManagerFactory);
    }

}

第二套数据库配置

import com.zaxxer.hikari.HikariDataSource;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
import org.springframework.boot.context.properties.ConfigurationProperties;
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 javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;

@Configuration
// 指定包扫描目录
@EnableJpaRepositories(basePackages = {"example.share.repository"}, entityManagerFactoryRef = "shareEntityManagerFactory", transactionManagerRef = "shareTransactionManager")
public class DatabaseShareConfiguration {

    @Bean(name = "shareDataSourceProperties")
    // 指定数据库配置前缀，然后可以通过 share.datasource.url 这种格式去配置第二套数据源配置
    @ConfigurationProperties("share.datasource")
    public DataSourceProperties dataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean(name = "shareDataSource")
    // 指定数据库配置前缀，然后可以通过 share.datasource.hikari.poolName 这种格式去配置第二套数据源配置
    @ConfigurationProperties("share.datasource.hikari")
    public DataSource dataSource(@Qualifier("shareDataSourceProperties") DataSourceProperties dataSourceProperties) {
        return dataSourceProperties.initializeDataSourceBuilder().type(HikariDataSource.class).build();
    }


    @Bean(name = "shareEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean
    shareEntityManagerFactory(
            EntityManagerFactoryBuilder builder,
            @Qualifier("shareDataSource") DataSource dataSource
    ) {
        return
                builder
                        .dataSource(dataSource)
                        // 指定扫描包地址
                        .packages("example.share.domain")
                        .persistenceUnit("share")
                        .build();
    }

    @Bean(name = "shareTransactionManager")
    public PlatformTransactionManager shareTransactionManager(
            @Qualifier("shareEntityManagerFactory") EntityManagerFactory
                    shareEntityManagerFactory
    ) {
        return new JpaTransactionManager(shareEntityManagerFactory);
    }
}

application.yml

# 主数据库配置
spring:
  datasource:
    type: com.zaxxer.hikari.HikariDataSource
    username: root
    url: jdbc:mysql://localhost:3306/
    password: 
    hikari:
      poolName: Hikari
      auto-commit: false

# 第二套数据库配置
share:
  datasource:
    type: com.zaxxer.hikari.HikariDataSource
    url: jdbc:mysql://localhost:3307/
    username: root
    password:
    hikari:
      poolName: Share-Hikari
      auto-commit: false