分散式事務--XA 解決多個數據源操作
阿新 • • 發佈:2018-12-25
個人備忘
事務(官方解釋):是由一組sql語句組成的“邏輯處理單元”。
事務具有如下四個屬性,通常稱為事務的ACID屬性 :
1. 原子性(Atomicity): 事務是一個原子操作單元,要麼都執行,要麼都不執行。
2. 一致性(Consistent):在事務開始和完成時,資料都必須保持一致。
3. 隔離性(Isoation): 資料庫系統提供一定的隔離機制,保證事務在不受外部併發操作影響的“獨立”環境執行。
4. 永續性(Durabe): 事務完成之後,它對資料的修改是永久性的。
分散式事務 : 分散式事務就是指事務的參與者,支援事務的伺服器,資源伺服器,以及事務管理器分別位於不同的分散式系統的不同節點之上。
本質上來說,分散式事務就是為了保證“不同資料庫的資料一致性” 。
分散式事務產生場景 :
分散式事務管理器 :
XA 協議 是可以在資料庫conmit 之後進行回滾的。
常見分散式事務解決方案 :
通過日誌來記錄操作 ,從上到下任何一步有問題,就會rollback , 如下圖 :
XA優缺點:
常見資料庫都對XA 協議有支援,成本低。
XA相關框架:
Atomikos 程式碼實現:
基於ssm
//pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.xy</groupId>
<artifactId>springmvc-mybatis</artifactId>
<version >1.0-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
<spring.version>4.1.1.RELEASE</spring.version>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.15</version>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
<debug>true</debug>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<!--<configuration>-->
<!--<packagingExcludes>**/*.properties</packagingExcludes>-->
<!--</configuration>-->
</plugin>
<plugin>
<groupId>org.mortbay.jetty</groupId>
<artifactId>maven-jetty-plugin</artifactId>
<version>6.1.26</version>
<configuration>
<scanIntervalSeconds>10</scanIntervalSeconds>
<webAppConfig>
<contextPath>/maven-app</contextPath>
</webAppConfig>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.3.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.3.0</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.0.11</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>1.0.11</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.6</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>com.mchange</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.2.1</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.2.7</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.0.8</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.2.2</version>
</dependency>
<dependency>
<groupId>com.atomikos</groupId>
<artifactId>atomikos-util</artifactId>
<version>3.7.0</version>
</dependency>
<dependency>
<groupId>com.atomikos</groupId>
<artifactId>transactions-jta</artifactId>
<version>3.7.0</version>
</dependency>
<dependency>
<groupId>com.atomikos</groupId>
<artifactId>transactions</artifactId>
<version>3.7.0</version>
</dependency>
<dependency>
<groupId>com.atomikos</groupId>
<artifactId>transactions-api</artifactId>
<version>3.7.0</version>
</dependency>
<dependency>
<groupId>com.atomikos</groupId>
<artifactId>transactions-jdbc</artifactId>
<version>3.7.0</version>
</dependency>
<dependency>
<groupId>org.codehaus.btm</groupId>
<artifactId>btm</artifactId>
<version>2.1.4</version>
</dependency>
</dependencies>
</project>
spring-mybatis.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
xmlns:rabbit="http://www.springframework.org/schema/rabbit"
xmlns:cache="http://www.springframework.org/schema/cache" xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd http://www.springframework.org/schema/rabbit http://www.springframework.org/schema/rabbit/spring-rabbit.xsd
http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd">
<context:component-scan base-package="com.xy">
<context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<context:property-placeholder location="classpath:context/database.properties"/>
<tx:annotation-driven/>
<bean id="abstractXADataSource" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init"
destroy-method="close" abstract="true">
<property name="xaDataSourceClassName" value="com.mysql.jdbc.jdbc2.optional.MysqlXADataSource"/>
<property name="poolSize" value="10" />
<property name="minPoolSize" value="10"/>
<property name="maxPoolSize" value="30"/>
<property name="borrowConnectionTimeout" value="60"/>
<property name="reapTimeout" value="20"/>
<!-- 最大空閒時間 -->
<property name="maxIdleTime" value="60"/>
<property name="maintenanceInterval" value="60"/>
<property name="loginTimeout" value="60"/>
<property name="testQuery">
<value>select 1</value>
</property>
</bean>
<bean id="qadataSource" parent="abstractXADataSource">
<!-- value只要兩個資料來源不同就行,隨便取名 -->
<property name="uniqueResourceName" value="mysql/sitestone1" />
<property name="xaDataSourceClassName"
value="com.mysql.jdbc.jdbc2.optional.MysqlXADataSource" />
<property name="xaProperties">
<props>
<prop key="URL">${qa.db.url}</prop>
<prop key="user">${qa.db.user}</prop>
<prop key="password">${qa.db.password}</prop>
<prop key="pinGlobalTxToPhysicalConnection">true</prop>
</props>
</property>
</bean>
<bean id="devdataSource" parent="abstractXADataSource">
<!-- value只要兩個資料來源不同就行,隨便取名 -->
<property name="uniqueResourceName" value="mysql/sitestone" />
<property name="xaDataSourceClassName"
value="com.mysql.jdbc.jdbc2.optional.MysqlXADataSource" />
<property name="xaProperties">
<props>
<prop key="URL">${dev.db.url}</prop>
<prop key="user">${dev.db.user}</prop>
<prop key="password">${dev.db.password}</prop>
<prop key="pinGlobalTxToPhysicalConnection">true</prop>
</props>
</property>
</bean>
<bean id="qasqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="qadataSource" />
<property name="mapperLocations" value="classpath*:com/xy/dao/*.xml" />
</bean>
<bean id="devsqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="devdataSource" />
<property name="mapperLocations" value="classpath*:com/xy/daodev/*.xml" />
</bean>
<bean id="atomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager"
init-method="init" destroy-method="close">
<property name="forceShutdown">
<value>true</value>
</property>
</bean>
<bean id="atomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp">
<property name="transactionTimeout" value="300" />
</bean>
<bean id="transactionManager"
class="org.springframework.transaction.jta.JtaTransactionManager">
<property name="transactionManager">
<ref bean="atomikosTransactionManager"/>
</property>
<property name="userTransaction">
<ref bean="atomikosUserTransaction"/>
</property>
<!-- 必須設定,否則程式出現異常 JtaTransactionManager does not support custom isolation levels by default -->
<property name="allowCustomIsolationLevels" value="true"/>
</bean>
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.xy.dao"/>
<property name="sqlSessionFactoryBeanName" value="qasqlSessionFactory" />
</bean>
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<property name="basePackage" value="com.xy.daodev"/>
<property name="sqlSessionFactoryBeanName" value="devsqlSessionFactory" />
</bean>
</beans>
database.properties
qa.db.url=jdbc:mysql://localhost:3306/qa?useUnicode=true&characterEncoding=UTF-8
qa.db.user=root
qa.db.password=123456
dev.db.url=jdbc:mysql://localhost:3306/dev?useUnicode=true&characterEncoding=UTF-8
dev.db.user=root
dev.db.password=123456
jta.properties
com.atomikos.icatch.service=com.atomikos.icatch.standalone.UserTransactionServiceFactory
com.atomikos.icatch.console_file_name = tm.out
com.atomikos.icatch.log_base_name = tmlog
com.atomikos.icatch.tm_unique_name = com.atomikos.spring.jdbc.tm
com.atomikos.icatch.console_log_level = INFO
com.atomikos.icatch.output_dir=/hello/atomikos
com.atomikos.icatch.log_base_dir=/hello/atomikos
com.atomikos.icatch.serial_jta_transactions=false
java程式碼 :
service
package com.xy.service;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.xy.dao.NameQaMapper;
import com.xy.daodev.NameDevMapper;
import com.xy.model.NameDev;
import com.xy.model.NameQa;
@Service
public class NameService {
@Autowired
NameQaMapper qaMapper;
@Autowired
NameDevMapper devMapper;
@Transactional(rollbackFor=Exception.class)
public void addQaAndDev(boolean hasException) throws Exception{
NameQa nameQa = new NameQa();
nameQa.setNameQa("hello qa");
qaMapper.insert(nameQa);
NameDev dev = new NameDev();
dev.setNameDev("hello dev");
devMapper.insert(dev);
if (hasException) {
throw new Exception();
}
}
}
controller 程式碼
package com.xy.controller;
import com.xy.service.NameService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
/**
* Created by helloworld on 2014/11/22.
*/
@Controller
public class mybatisController {
@Autowired
NameService nameService;
@RequestMapping(value = "/addName", method = RequestMethod.GET)
ModelMap addName(@RequestParam("hasException") boolean hasException) {
try {
nameService.addQaAndDev(hasException);
} catch (Exception e) {
e.printStackTrace();
return new ModelMap("false");
}
return new ModelMap("true");
}
}
model 和 mapper 沒什麼可說的,這裡就不貼上了。