First look at the figure below. The
above figure shows the producer link of mq transaction message to solve distributed transaction, and the consumer can consume normally.
show your code
According to the above process, we can use rocketmq to easily implement the following code. In order to reduce part of the business code intrusion, a little bit of encapsulation is done; the
following projects are based on springboot 2.1.3, and jdbc is introduced here. You need to pay attention to that you can share the transaction manager with mybatis and mybatis-plus (I want to know how jdbc and mybatis share the transaction manager , Baidu on its own). If you are jpa or habinate, you can not encapsulate this way.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.apache.rocketmq</groupId>
<artifactId>rocketmq-spring-boot-starter</artifactId>
<version>2.1.1</version>
</dependency>
You need to insert the following table in your business database to record the transaction log.
CREATE TABLE `transaction_log` (
`id` int(20) NOT NULL AUTO_INCREMENT,
`trx_id` varchar(128) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `idx_transaction_id` (`trx_id`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4;
Since we use rocketmq-spring-boot-starterthis automatic configuration, we can use it directly RocketMQTemplateto send messages, which is very convenient
for configuration in the demo
rocketmq.name-server=127.0.0.1:9876
rocketmq.producer.group=tx_group
rocketmq.producer.send-message-timeout=3000
package com.xxx.fw.rocketmq.trx.core;
import com.xxx.fw.rocketmq.trx.config.TrxContextHolder;
import javax.annotation.Resource;
import org.apache.rocketmq.spring.core.RocketMQLocalTransactionListener;
import org.apache.rocketmq.spring.core.RocketMQLocalTransactionState;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.messaging.Message;
/**
* @Description 抽象类让业务继承此类，并实现doBusiness方法，实现不同的业务定制
* @Author 姚仲杰
* * @Date 2020/12/21 20:51
*/
public abstract class AbstractTransactionListener implements RocketMQLocalTransactionListener {
private final static Logger LOGGER= LoggerFactory.getLogger(AbstractTransactionListener.class);
@Resource
TransactionLogService transactionLogService;
public abstract void doBusiness(Object o);
/**这个方法中执行本地事务
* @param message 已发送到mq的事务消息
* @param o 要保存到库的对象
* @return
*/
@Override
public RocketMQLocalTransactionState executeLocalTransaction(Message message, Object o) {
RocketMQLocalTransactionState state;
TrxContextHolder.setTrxId(message.getHeaders().getId().toString());
try{
LOGGER.info("执行业务逻辑，trx_id:[{}]",message.getHeaders().getId());
doBusiness(o);
state=RocketMQLocalTransactionState.COMMIT;
LOGGER.info("执行业务逻辑---[COMMIT]");
}catch(Exception ex){
LOGGER.info("消息事务回滚[ROLLBACK] {}",ex);
state=RocketMQLocalTransactionState.ROLLBACK;
}
return state;
}
/**此方法提供统一回查
* @param message 回查的消息数据
* @return
*/
@Override
public RocketMQLocalTransactionState checkLocalTransaction(Message message) {
RocketMQLocalTransactionState state=RocketMQLocalTransactionState.UNKNOWN;
if (transactionLogService.query(message.getHeaders().getId().toString())>0){
LOGGER.info("commit msg trx_id:{}",message.getHeaders().getId());
state=RocketMQLocalTransactionState.COMMIT;
}else{
LOGGER.info("LocalTransaction review [UNKNOWN] will try again");
state=RocketMQLocalTransactionState.UNKNOWN;
}
return state;
}
}
Custom annotation
package com.xxx.fw.rocketmq.trx.config;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @Description TODO
* @Author 姚仲杰
* @Date 2020/12/28 11:28
*/
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Inherited
public @interface MqTrx {
}
Section processing
package com.xxx.fw.rocketmq.trx.aspect;
import com.xxx.fw.rocketmq.trx.config.MqTrx;
import com.xxx.fw.rocketmq.trx.config.TrxContextHolder;
import com.xxx.fw.rocketmq.trx.core.TransactionLogService;
import javax.annotation.Resource;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
import org.springframework.transaction.annotation.EnableTransactionManagement;
/**
* @Description TODO
* @Author 姚仲杰
* @Date 2020/12/28 11:29
*/
//此处需介绍下注解顺序，当前注解需包在事务注解中执行，注解先进后出所以让事务注解order为0 本注解顺序为1 则先进事务注解在进本注解
@EnableTransactionManagement(order = 0)
@Order(1)
@Component
@Aspect
public class TrxAspect {
public static final Logger LOGGER= LoggerFactory.getLogger(TrxAspect.class);
@Resource
TransactionLogService transactionLogService;
@Pointcut("@annotation(com.xxx.fw.rocketmq.trx.config.MqTrx)")
public void pointcut(){
};
@After("pointcut() && @annotation(mqTrx)")
public void after(JoinPoint joinPoint, MqTrx mqTrx){
try {
String id = TrxContextHolder.getTrxId();
transactionLogService.insert(id);
LOGGER.info("事务消息日志入库成功，trx_id:[{}]", id);
}finally {
TrxContextHolder.remove();
}
}
}
mq transaction context management
package com.xxx.fw.rocketmq.trx.config;
import java.util.HashMap;
import java.util.Map;
/**
* @Description TODO
* @Author 姚仲杰
* @Date 2020/12/28 11:42
*/
public class TrxContext {
private ThreadLocal<Map<String,String>> threadLocal=new ThreadLocal<Map<String,String>>(){
@Override
protected Map<String, String> initialValue() {
return new HashMap<String, String>();
}
};
public String put(String key, String value) {
return threadLocal.get().put(key, value);
}
public String get(String key) {
return threadLocal.get().get(key);
}
public String remove(String key) {
return threadLocal.get().remove(key);
}
public Map<String, String> entries() {
return threadLocal.get();
}
}
package com.xxx.fw.rocketmq.trx.config;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* @Description 此类用于传递事务id到切面中，即发送完成后执行本地事务前，将trx_id放入本地线程，然后通过切面把事务id写入到事务日志表
* @Author 姚仲杰
* @Date 2020/12/28 11:46
*/
public class TrxContextHolder {
private static final Logger LOGGER = LoggerFactory.getLogger(TrxContextHolder.class);
public static final TrxContext TRX_CONTEXT_HOLDER=new TrxContext();
public static final String TRX_ID="TRX_ID";
public static String getTrxId(){
return TRX_CONTEXT_HOLDER.get(TRX_ID);
}
public static void setTrxId(String trxId){
if (LOGGER.isDebugEnabled()) {
LOGGER.debug("set trx_id:[{}]", trxId);
}
TRX_CONTEXT_HOLDER.put(TRX_ID, trxId);
}
public static String remove() {
String trxId = TRX_CONTEXT_HOLDER.remove(TRX_ID);
if (LOGGER.isDebugEnabled()) {
LOGGER.debug("remove trx_id:[{}] ", trxId);
}
return trxId;
}
}
package com.xxx.fw.rocketmq.trx.core;
import javax.annotation.Resource;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
/**
* @Description 这里使用jdbcTemplate内置日志入库和查询操作让业务开发无需关注这些代码只需要添加一个注解即可
* @Author 姚仲杰
* @Date 2020/12/28 19:32
*/
@Component
public class TransactionLogService {
private final static String INSERT_TRX_LOG="insert into transaction_log (trx_id)value('%s')";
private final static String CHECK_TRX_LOG="select count(*) from transaction_log where trx_id='%s'";
@Resource
JdbcTemplate jdbcTemplate;
public int insert(String trxId){
if (StringUtils.isEmpty(trxId)){
throw new IllegalArgumentException("trxId must not be null");
}
int update = jdbcTemplate.update(String.format(INSERT_TRX_LOG, trxId));
return update;
}
public int query(String trxId){
if (StringUtils.isEmpty(trxId)){
throw new IllegalArgumentException("trxId must not be null");
}
int count = jdbcTemplate
.queryForObject(String.format(CHECK_TRX_LOG, trxId), int.class);
return count;
}
}
Provide packaged delivery services and tools
package com.xxx.fw.rocketmq.trx.core;
import com.xxx.fw.rocketmq.trx.util.TagsUtil;
import javax.annotation.Resource;
import org.apache.rocketmq.client.producer.TransactionSendResult;
import org.apache.rocketmq.spring.core.RocketMQTemplate;
import org.springframework.messaging.Message;
import org.springframework.messaging.support.MessageBuilder;
import org.springframework.stereotype.Component;
/**
* @Description 为了拼接tag实现不同业务
* @Author 姚仲杰
* @Date 2020/12/28 20:21
*/
@Component
public class TrxService {
@Resource
RocketMQTemplate rocketMQTemplate;
/**
* @param msg 发送给消息队列得消息
* @param tag 消息队列得tag，组装后形成trx_topic:tag
* @param o 要入库得数据
* @return
*/
public TransactionSendResult send(String msg,String tag,Object o){
Message message = MessageBuilder.withPayload(msg).build();
TransactionSendResult result = rocketMQTemplate
.sendMessageInTransaction(TagsUtil.bindTag(tag), message, o);
return result;
}
}
Tools
package com.xxx.fw.rocketmq.trx.util;
import org.springframework.util.StringUtils;
/**
* @Description 拼接tag
* @Author 姚仲杰
* @Date 2020/12/28 19:59
*/
public class TagsUtil {
public static final String TRX_TOPIC="trx_topic:";
public static String bindTag(String tag){
if (StringUtils.isEmpty(tag)){
throw new IllegalArgumentException("trx_tag must not be empty");
}
return TRX_TOPIC+tag;
}
}