SpringBoot使用jta+atomikos解決多數據源分佈式事務

多數據源的兩種情況

SpringBoot 中多數據源大致可以分爲兩種：

1. 垂直分割模式
2. 類似水平分割模式

類似水平分割模式，不同區域都擁有數據庫，每個區域的數據庫數據相同，通過不同區域的賬戶選擇登錄哪個數據庫。

垂直分割模式

垂直分割模式，將整個數據庫根據模塊拆分成多個數據庫，每個數據庫是單獨一個數據源，這樣就涉及到多數據源的分佈式事務問題。

application.properties

這裏配置了兩個數據庫。

mybatis.type-aliases-package = com.yellow.etc.mapper
mybatis.mapper-location = classpath:mapping/*.xml

spring.datasource.test1.driver-class-name = com.mysql.jdbc.Driver
spring.datasource.test1.jdbc-url = jdbc:mysql://localhost:3306/test01?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
spring.datasource.test1.username = root
spring.datasource.test1.password = 123456

spring.datasource.test2.driver-class-name = com.mysql.jdbc.Driver
spring.datasource.test2.jdbc-url = jdbc:mysql://localhost:3306/test02?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
spring.datasource.test2.username = root
spring.datasource.test2.password = 123456

DataSourceConfig

通過 Java 配置，註冊兩個數據源，分別爲 test1DataSource 與 test2DataSource。

注意！配置兩個數據源，需要在主數據源上打@Primary註解，否則會報以下異常

org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type ‘org.springframework.transaction.TransactionManager’ available: expected single matching bean but found 2: test1TransactionManager,test2TransactionManager

import javax.sql.DataSource;
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.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.jdbc.datasource.DataSourceTransactionManager;

@Configuration
@MapperScan(basePackages = "com.yellow.etc.mapper.test01", sqlSessionFactoryRef = "test1SqlSessionFactory")
public class DataSource1Config {
	/**
	 * @methodDesc:功能描述:(配置test01數據庫)
	 * @return
	 */
	@Bean(name = "test1DataSource")
	@ConfigurationProperties(prefix = "spring.datasource.test1")
	@Primary //沒有該註解會報異常
	public DataSource testDataSource() {
		return DataSourceBuilder.create().build();
	}
	/**
	 * @methodDesc:功能描述:(test1 sql會話工廠)
	 * @param dataSource
	 * @return
	 * @throws Exception 
	 */
	@Bean(name = "test1SqlSessionFactory")
	@Primary
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource) 
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		return bean.getObject();
	}
	/**
	 * @methodDesc:功能描述:(test1 事務管理)
	 * @param dataSource
	 * @return
	 */
	@Bean(name = "test1TransactionManager")
	@Primary
	public DataSourceTransactionManager tesTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
		return new DataSourceTransactionManager(dataSource);
	}
	/**
	 * @methodDesc:功能描述:()
	 * @param sqlSessionFactory
	 * @return
	 */
	@Bean(name = "test1SqlSessionTemplate")
	@Primary
	public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
		return new SqlSessionTemplate(sqlSessionFactory);
	}
}

import javax.sql.DataSource;
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.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.jdbc.datasource.DataSourceTransactionManager;

@Configuration
@MapperScan(basePackages = "com.yellow.etc.mapper.test02", sqlSessionFactoryRef = "test2SqlSessionFactory")
public class DataSource2Config {
	/**
	 * @methodDesc:功能描述:(配置test01數據庫)
	 * @return
	 */
	@Bean(name = "test2DataSource")
	@ConfigurationProperties(prefix = "spring.datasource.test2")
	public DataSource testDataSource() {
		return DataSourceBuilder.create().build();
	}
	/**
	 * @methodDesc:功能描述:(test1 sql會話工廠)
	 * @param dataSource
	 * @return
	 * @throws Exception 
	 */
	@Bean(name = "test2SqlSessionFactory")
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource) 
			throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		return bean.getObject();
	}
	/**
	 * @methodDesc:功能描述:(test1 事務管理)
	 * @param dataSource
	 * @return
	 */
	@Bean(name = "test2TransactionManager")
	public DataSourceTransactionManager tesTransactionManager(@Qualifier("test2DataSource") DataSource dataSource) {
		return new DataSourceTransactionManager(dataSource);
	}
	/**
	 * @methodDesc:功能描述:()
	 * @param sqlSessionFactory
	 * @return
	 */
	@Bean(name = "test2SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
		return new SqlSessionTemplate(sqlSessionFactory);
	}
}

測試

編寫兩個 mapper 對應兩個數據庫，都是簡單的插入方法，在 service 中調用這兩個方法，手動添加一個除0異常，查看數據庫狀態。

@Transactional
public int addUser(String name, Integer age) {
	userMapper01.insert(name, age);
	userMapper02.insert(name, age);
	int i = 1/0;
	return 2;
}

調用方法後發現，使用 test01 作爲主數據源，當發生異常回滾時，只會回滾該數據源對應的數據庫數據，對 test02 數據不會進行回滾操作。這就不符合事務的原子性，要麼同時成功，要麼同時失敗。

解決方法

這裏我們可以使用 jta+atomikos 處理多數據源事務問題。

jta+atomikos 相當於把多個數據源的事務管理在一起，進行簡單的代理，幫助我們在事務提交或回滾時進行操作。

pom.xml

在 pom.xml 中添加以下依賴。

<!-- jta+atomic -->
<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-jta-atomikos</artifactId>
</dependency>

application.properties

mybatis.type-aliases-package = com.yellow.etc.mapper
mybatis.mapper-location = classpath:mapping/*.xml

spring.datasource.test1.driver-class-name = com.mysql.jdbc.Driver
spring.datasource.test1.jdbc-url = jdbc:mysql://localhost:3306/test01?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
spring.datasource.test1.username = root
spring.datasource.test1.password = 123456
spring.datasource.test1.minPoolSize = 3
spring.datasource.test1.maxPoolSize = 25
spring.datasource.test1.maxLifetime = 20000
spring.datasource.test1.borrowConnectionTimeout = 30
spring.datasource.test1.loginTimeout = 30
spring.datasource.test1.maintenanceInterval = 60
spring.datasource.test1.maxIdleTime = 60

spring.datasource.test2.driver-class-name = com.mysql.jdbc.Driver
spring.datasource.test2.jdbc-url = jdbc:mysql://localhost:3306/test02?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8
spring.datasource.test2.username = root
spring.datasource.test2.password = 123456
spring.datasource.test2.minPoolSize = 3
spring.datasource.test2.maxPoolSize = 25
spring.datasource.test2.maxLifetime = 20000
spring.datasource.test2.borrowConnectionTimeout = 30
spring.datasource.test2.loginTimeout = 30
spring.datasource.test2.maintenanceInterval = 60

配置類

import org.springframework.boot.context.properties.ConfigurationProperties;
import lombok.Data;

@Data
@ConfigurationProperties(prefix = "spring.datasource.test1")
public class DBConfig01 {
	private String url;
	private String username;
	private String password;
	private int minPoolSize;
	private int maxPoolSize;
	private int maxLifetime;
	private int borrowConnectionTimeout;
	private int loginTimeout;
	private int maintenanceInterval;
	private int maxIdleTime;
	private String testQuery;
}

import org.springframework.boot.context.properties.ConfigurationProperties;
import lombok.Data;

@Data
@ConfigurationProperties(prefix = "spring.datasource.test2")
public class DBConfig02 {
	private String url;
	private String username;
	private String password;
	private int minPoolSize;
	private int maxPoolSize;
	private int maxLifetime;
	private int borrowConnectionTimeout;
	private int loginTimeout;
	private int maintenanceInterval;
	private int maxIdleTime;
	private String testQuery;
}

配置數據源

import javax.sql.DataSource;
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.boot.jta.atomikos.AtomikosDataSourceBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
/**
  * 類名稱：JTAConfiguration01      
  * 創建人：98   
  * 創建時間：2019年12月18日 上午11:15:11   
 * @version
 */
@Configuration
@MapperScan(basePackages = "com.yellow.etc.mapper.test01", sqlSessionTemplateRef = "test1SqlSessionTemplate")
public class JTAConfiguration01 {
	
	/**
	 * @methodDesc:功能描述:(配置數據源)
	 * @param testConfig
	 * @return
	 */
	@Primary
	@Bean(name = "test1DataSource")
	public DataSource testDataSource(DBConfig01 testConfig) {
		MysqlXADataSource mysqlXaDataSource = new MysqlXADataSource();
		mysqlXaDataSource.setUrl(testConfig.getUrl());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
		mysqlXaDataSource.setPassword(testConfig.getPassword());
		mysqlXaDataSource.setUser(testConfig.getUsername());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
		// 將本地事務註冊到Atomikos
		AtomikosDataSourceBean xaDataSource = new AtomikosDataSourceBean();
		xaDataSource.setXaDataSource(mysqlXaDataSource);
		xaDataSource.setUniqueResourceName("test1DataSource");
		// 配置信息
		xaDataSource.setMinPoolSize(testConfig.getMinPoolSize());
		xaDataSource.setMaxPoolSize(testConfig.getMaxPoolSize());
		xaDataSource.setMaxLifetime(testConfig.getMaxLifetime());
		xaDataSource.setBorrowConnectionTimeout(testConfig.getBorrowConnectionTimeout());
		xaDataSource.setLoginTimeout(testConfig.getLoginTimeout());
		xaDataSource.setMaintenanceInterval(testConfig.getMaintenanceInterval());
		xaDataSource.setMaxIdleTime(testConfig.getMaxIdleTime());
		xaDataSource.setTestQuery(testConfig.getTestQuery());
		return xaDataSource;
	}
	
	@Bean(name = "test1SqlSessionFactory")
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource) throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		return bean.getObject();
	}
 
	@Bean(name = "test1SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}
}

import javax.sql.DataSource;
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.boot.jta.atomikos.AtomikosDataSourceBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
/**
  * 類名稱：JTAConfiguration02      
  * 創建人：98   
  * 創建時間：2019年12月18日 上午11:14:36   
 * @version
 */
@Configuration
@MapperScan(basePackages = "com.yellow.etc.mapper.test02", sqlSessionTemplateRef = "test2SqlSessionTemplate")
public class JTAConfiguration02 {
	/**
	 * @methodDesc:功能描述:(配置數據源)
	 * @param testConfig
	 * @return
	 */
	@Primary
	@Bean(name = "test2DataSource")
	public DataSource testDataSource(DBConfig02 testConfig) {
		MysqlXADataSource mysqlXaDataSource = new MysqlXADataSource();
		mysqlXaDataSource.setUrl(testConfig.getUrl());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
		mysqlXaDataSource.setPassword(testConfig.getPassword());
		mysqlXaDataSource.setUser(testConfig.getUsername());
		mysqlXaDataSource.setPinGlobalTxToPhysicalConnection(true);
		// 將本地事務註冊到Atomikos
		AtomikosDataSourceBean xaDataSource = new AtomikosDataSourceBean();
		xaDataSource.setXaDataSource(mysqlXaDataSource);
		xaDataSource.setUniqueResourceName("test2DataSource");
		// 配置信息
		xaDataSource.setMinPoolSize(testConfig.getMinPoolSize());
		xaDataSource.setMaxPoolSize(testConfig.getMaxPoolSize());
		xaDataSource.setMaxLifetime(testConfig.getMaxLifetime());
		xaDataSource.setBorrowConnectionTimeout(testConfig.getBorrowConnectionTimeout());
		xaDataSource.setLoginTimeout(testConfig.getLoginTimeout());
		xaDataSource.setMaintenanceInterval(testConfig.getMaintenanceInterval());
		xaDataSource.setMaxIdleTime(testConfig.getMaxIdleTime());
		xaDataSource.setTestQuery(testConfig.getTestQuery());
		return xaDataSource;
	}
	
	@Bean(name = "test2SqlSessionFactory")
	public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource) throws Exception {
		SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
		bean.setDataSource(dataSource);
		return bean.getObject();
	}
 
	@Bean(name = "test2SqlSessionTemplate")
	public SqlSessionTemplate testSqlSessionTemplate(
			@Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
		return new SqlSessionTemplate(sqlSessionFactory);
	}
}

啓動類

@SpringBootApplication
// 加載配置類
@EnableConfigurationProperties(value = {DBConfig01.class, DBConfig02.class})
public class SpringBootDataSourceApplication {
	public static void main(String[] args) {
		SpringApplication.run(SpringBootDataSourceApplication.class, args);
	}
}