orm-helper

A helper library for ORM layer with Spring and JPA. It also provides auto switch between Master - Slave Datasource

Versions

• Final: 1.0-FINAL
• Release: 1.5-SNAPSHOT

Usage

Maven

• Maven repository entry in pom.xml

<repositories>
    <repository>
        <id>orm-helper-mvn-repo</id>
        <url>https://raw.github.com/Consolefire/orm-helper/mvn-repo/</url>
        <!-- Optional: to always check the repo to refresh jar --> 
        <snapshots>
            <enabled>true</enabled>
            <updatePolicy>always</updatePolicy>
        </snapshots>
    </repository>
</repositories>

• Maven dependency

<dependency>
    <groupId>com.consolefire.orm.helper</groupId>
    <artifactId>orm-helper</artifactId>
    <version>${orm.helper.version}</version>
</dependency>

Gradle

• Add repository url like

maven { url "https://raw.github.com/Consolefire/orm-helper/mvn-repo" }

• Add Dependency

compile(group: 'com.consolefire.orm.helper', name: 'orm-helper', version: "${orm.helper.version}")

Changes in current version

1.5-SNAPSHOT

• Changed GenericJpaDao.identityFieldName as protected. In case the client want to use Hibernate mapping Xml files, then in the extended DAO class, set super.identityFieldName. This will make saveOrUpdate(e) to work as expected.

1.4-SNAPSHOT

• Added constants for Bean Names used in the Configuration.
• Modified to have java.util.Properties as JPA Properties.
• Added bean to scan Hibernate/ORM mapping files.

Sample using Maven and Mysql

Complete example is available here.

• Add 2 databases: Master and Slave
• Insert records in both database

drop database if exists office_master;
create database office_master;
use office_master;
create table employees ( 
    id bigint not null auto_increment, 
    email varchar(150) not null, 
    name varchar(150) not null, 
    created_at timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
    created_by varchar(150) NOT NULL DEFAULT 'SOMEONE',
    updated_at timestamp NULL DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
    updated_by varchar(150) DEFAULT NULL,
    primary key (id)
);

alter table employees add constraint UK_hxpym1ml3cufk46aws6660klf unique (name, email);
insert  into employees (email, name) values ('sabuj.das@gmail.com', 'Sabuj Das');

drop database if exists office_slave;
create database office_slave;
use office_slave;

create table employees ( 
    id bigint not null auto_increment, 
    email varchar(150) not null, 
    name varchar(150) not null, 
    created_at timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
    created_by varchar(150) NOT NULL DEFAULT 'SOMEONE',
    updated_at timestamp NULL DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
    updated_by varchar(150) DEFAULT NULL,
    primary key (id)
);

alter table employees add constraint UK_hxpym1ml3cufk46aws6660klf unique (name, email);
insert  into employees (email, name) values ('sabuj.das@hotmail.com', 'Sabuj Das');

• Create properties to provide inputs

spring.jpa.generate-ddl=false
spring.jpa.hibernate.ddl-auto=none
spring.data.jpa.repositories.enabled=false
persistence.databaseName=MYSQL
persistence.driverClass=com.mysql.jdbc.Driver
persistence.slave.url=jdbc:mysql://slave_host:3306/office_slave
persistence.slave.userName=ro
persistence.slave.password=ro_pass
persistence.master.url=jdbc:mysql://master_host:3306/office_master
persistence.master.userName=rw
persistence.master.password=rw_pass
orm.helper.persistence.properties.hbmToDDLAuto=validate
orm.helper.persistence.properties.showSql=true
orm.helper.persistence.properties.formatSql=true
orm.helper.persistence.properties.dialect=org.hibernate.dialect.MySQL5Dialect

• Create bean configuration

@Configuration
public class PersistenceConfig {

    @Value("${persistence.driverClass}")
    private String driverClass;
    @Value("${persistence.master.url}")
    private String masterUrl;
    @Value("${persistence.master.userName}")
    private String masterUser;
    @Value("${persistence.master.password}")
    private String masterPass;
    @Value("${persistence.slave.url}")
    private String slaveUrl;
    @Value("${persistence.slave.userName}")
    private String slaveUser;
    @Value("${persistence.slave.password}")
    private String slavePass;


    @Bean(name = "ormHelper.entityPackagesToScan")
    public List<String> entityPackagesToScan(){
        List<String> list = new ArrayList<>();
        list.add("com.consolefire.orm.sample.entity");
        return list;
    }

    @Bean(name = "ormHelper.masterDataSource")
    public DataSource masterDS(){
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName(driverClass);
        dataSource.setUrl(masterUrl);
        dataSource.setUsername(masterUser);
        dataSource.setPassword(masterPass);
        return dataSource;
    }

    @Bean(name = "ormHelper.slaveDataSource")
    public DataSource slaveDS(){
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName(driverClass);
        dataSource.setUrl(slaveUrl);
        dataSource.setUsername(slaveUser);
        dataSource.setPassword(slavePass);
        return dataSource;
    }

    @Bean(name = "ormHelper.defaultDataSourceType")
    public DataSourceTypeContext.DataSourceType defaultDsType(){
        return DataSourceTypeContext.DataSourceType.SLAVE;
    }
}

• Datasource Switch is done by the transactional property

@Service
public class EmployeeServiceImpl implements EmployeeService {

    @Autowired
    private EmployeeDao employeeDao;

    @Transactional(propagation = Propagation.REQUIRES_NEW, readOnly = false)
    public Employee writeToMaster(Employee employee) {
        return employeeDao.save(employee);
    }

    @Transactional(propagation = Propagation.REQUIRES_NEW, readOnly = false)
    public Employee readFromMaster(Long id) {
        return employeeDao.find(id);
    }

    @Transactional(propagation = Propagation.REQUIRES_NEW, readOnly = true)
    public Employee readFromSlave(Long id) {
        return employeeDao.find(id);
    }
}

• Test config

@Configuration
@ComponentScan(basePackages = {"com.consolefire.orm.sample", "com.consolefire.orm.helper"})
@EnableAspectJAutoProxy(proxyTargetClass = true)
public class TestConfig {
    @Bean
    public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
        return new PropertySourcesPlaceholderConfigurer();
    }
}