一,shardingshpere为什么要整合seata?

分库分表是数据库扩展中最常用的处理方法,

shardingshpere作为使用最广泛的分表中间件,

如果不支持分布式事务,则它的数据一致性就会打很大的折扣了

shardingsphere实现了对分布式事务seata的支持,

对于数据有高要求的应用来说,当然需要整合seata

说明:刘宏缔的架构森林是一个专注架构的博客,地址:https://www.cnblogs.com/architectforest

对应的源码可以访问这里获取: https://github.com/liuhongdi/

说明:作者:刘宏缔 邮箱: 371125307@qq.com

二,演示项目的相关信息

1,项目地址:

https://github.com/liuhongdi/shardingseata3

2,项目功能说明:

演示了shardingsphere整合seata,

数据源使用了druid

3,项目结构:如图:

三,配置文件说明

1,pom.xml

        <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<!--exclude log-->
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--mybatis begin-->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.3</version>
</dependency>
<!--druid begin-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.23</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>
<dependency>
<groupId>com.lmax</groupId>
<artifactId>disruptor</artifactId>
<version>3.4.2</version>
</dependency>
<!--mysql begin-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!--pagehelper begin-->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>
<!--thymeleaf begin-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<!--seata begin-->
<dependency>
<groupId>io.seata</groupId>
<artifactId>seata-all</artifactId>
<version>1.3.0</version>
</dependency>
<!--shardingsphere begin-->
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>sharding-jdbc-spring-boot-starter</artifactId>
<version>4.1.1</version>
</dependency>
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>sharding-jdbc-spring-namespace</artifactId>
<version>4.1.1</version>
</dependency>
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>sharding-transaction-base-seata-at</artifactId>
<version>4.1.1</version>
</dependency>
<!--aop begin-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-aop</artifactId>
</dependency>

2,application.properties

#error
server.error.include-stacktrace=always
#error
logging.level.org.springframework.web=trace
#thymeleaf
spring.thymeleaf.cache=false
spring.thymeleaf.encoding=UTF-8
spring.thymeleaf.mode=HTML
spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html #shardingsphere
spring.shardingsphere.datasource.names=store,saleorder01,saleorder02 spring.shardingsphere.datasource.store.type=com.alibaba.druid.pool.DruidDataSource
spring.shardingsphere.datasource.store.driver-class-name=com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.store.url=jdbc:mysql://127.0.0.1:3306/store?characterEncoding=utf-8
spring.shardingsphere.datasource.store.username=root
spring.shardingsphere.datasource.store.password=lhddemo
spring.shardingsphere.datasource.store.filters=stat,wall,log4j2
spring.shardingsphere.datasource.store.connectionProperties=druid.stat.mergeSql\=true;druid.stat.slowSqlMillis\=5000 spring.shardingsphere.datasource.saleorder01.type=com.alibaba.druid.pool.DruidDataSource
spring.shardingsphere.datasource.saleorder01.driver-class-name=com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.saleorder01.url=jdbc:mysql://127.0.0.1:3306/saleorder01?characterEncoding=utf-8
spring.shardingsphere.datasource.saleorder01.username=root
spring.shardingsphere.datasource.saleorder01.password=lhddemo
spring.shardingsphere.datasource.saleorder01.filters=stat,wall,log4j2
spring.shardingsphere.datasource.saleorder01.connectionProperties=druid.stat.mergeSql\=true;druid.stat.slowSqlMillis\=5000 spring.shardingsphere.datasource.saleorder02.type=com.alibaba.druid.pool.DruidDataSource
spring.shardingsphere.datasource.saleorder02.driver-class-name=com.mysql.cj.jdbc.Driver
spring.shardingsphere.datasource.saleorder02.url=jdbc:mysql://127.0.0.1:3306/saleorder02?characterEncoding=utf-8
spring.shardingsphere.datasource.saleorder02.username=root
spring.shardingsphere.datasource.saleorder02.password=lhddemo
spring.shardingsphere.datasource.saleorder02.filters=stat,wall,log4j2
spring.shardingsphere.datasource.saleorder02.connectionProperties=druid.stat.mergeSql\=true;druid.stat.slowSqlMillis\=5000 spring.shardingsphere.sharding.default-data-source-name=store
spring.shardingsphere.sharding.default-database-strategy.standard.sharding-column=orderId
spring.shardingsphere.sharding.default-database-strategy.standard.precise-algorithm-class-name=com.shardingseata3.demo.algorithm.DatabasePreciseShardingAlgorithm spring.shardingsphere.sharding.binding-tables=t_order
spring.shardingsphere.sharding.tables.t_order.actual-data-nodes=saleorder0$->{1..1}.t_order_$->{1..2},saleorder0$->{2..2}.t_order_$->{3..4}
spring.shardingsphere.sharding.tables.t_order.table-strategy.standard.sharding-column=orderId
spring.shardingsphere.sharding.tables.t_order.table-strategy.standard.precise-algorithm-class-name=com.shardingseata3.demo.algorithm.OrderTablePreciseShardingAlgorithm
spring.shardingsphere.props.sql.show=true #mybatis
mybatis.mapper-locations=classpath:/mapper/*Mapper.xml
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

3,数据库:

共3个:salesorder01/saleorder02/store

建表sql:

我们创建两个库:saleorder01,saleorder02

然后在各个库内各创建两个数据表:

saleorder01库包括t_order_1,t_order_2

saleorder02库包括t_order_3,t_order_4

CREATE TABLE `t_order_4` (
`orderId` bigint(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'id',
`goodsName` varchar(250) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL DEFAULT '' COMMENT 'name',
PRIMARY KEY (`orderId`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT='order4'

store库的goods表:

CREATE TABLE `goods` (
`goodsId` bigint(11) unsigned NOT NULL AUTO_INCREMENT COMMENT 'id',
`goodsName` varchar(500) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL DEFAULT '' COMMENT 'name',
`subject` varchar(200) NOT NULL DEFAULT '' COMMENT '标题',
`price` decimal(15,2) NOT NULL DEFAULT '0.00' COMMENT '价格',
`stock` int(11) NOT NULL DEFAULT '0' COMMENT 'stock',
PRIMARY KEY (`goodsId`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT='商品表'

插入一条示例数据:

INSERT INTO `goods` (`goodsId`, `goodsName`, `subject`, `price`, `stock`) VALUES
(3, '100分电动牙刷', '好用到让你爱上刷牙', '59.00', 96);

4,file.conf

transport {
# tcp udt unix-domain-socket
type = "TCP"
#NIO NATIVE
server = "NIO"
#enable heartbeat
heartbeat = true
#thread factory for netty
thread-factory {
boss-thread-prefix = "NettyBoss"
worker-thread-prefix = "NettyServerNIOWorker"
server-executor-thread-prefix = "NettyServerBizHandler"
share-boss-worker = false
client-selector-thread-prefix = "NettyClientSelector"
client-selector-thread-size = 1
client-worker-thread-prefix = "NettyClientWorkerThread"
# netty boss thread size,will not be used for UDT
boss-thread-size = 1
#auto default pin or 8
worker-thread-size = 8
}
}
service {
vgroupMapping.my_test_tx_group = "default"
#only support when registry.type=file, please don't set multiple addresses
default.grouplist = "127.0.0.1:8091"
#degrade, current not support
enableDegrade = false
#disable seata
disableGlobalTransaction = false
} client {
async.commit.buffer.limit = 10000
lock {
retry.internal = 10
retry.times = 30
}
}

5,registry.conf

registry {
# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
type = "file" nacos {
application = "seata-server"
serverAddr = "127.0.0.1:8848"
group = "SEATA_GROUP"
namespace = ""
cluster = "default"
username = ""
password = ""
}
eureka {
serviceUrl = "http://localhost:8761/eureka"
application = "default"
weight = "1"
}
redis {
serverAddr = "localhost:6379"
db = 0
password = ""
cluster = "default"
timeout = 0
}
zk {
cluster = "default"
serverAddr = "127.0.0.1:2181"
sessionTimeout = 6000
connectTimeout = 2000
username = ""
password = ""
}
consul {
cluster = "default"
serverAddr = "127.0.0.1:8500"
}
etcd3 {
cluster = "default"
serverAddr = "http://localhost:2379"
}
sofa {
serverAddr = "127.0.0.1:9603"
application = "default"
region = "DEFAULT_ZONE"
datacenter = "DefaultDataCenter"
cluster = "default"
group = "SEATA_GROUP"
addressWaitTime = "3000"
}
file {
name = "file.conf"
}
} config {
# file、nacos 、apollo、zk、consul、etcd3
type = "file" nacos {
serverAddr = "127.0.0.1:8848"
namespace = ""
group = "SEATA_GROUP"
username = ""
password = ""
}
consul {
serverAddr = "127.0.0.1:8500"
}
apollo {
appId = "seata-server"
apolloMeta = "http://192.168.1.204:8801"
namespace = "application"
}
zk {
serverAddr = "127.0.0.1:2181"
sessionTimeout = 6000
connectTimeout = 2000
username = ""
password = ""
}
etcd3 {
serverAddr = "http://localhost:2379"
}
file {
name = "file.conf"
}
}

6,seata.conf

client {
application.id = my_test_tx
transaction.service.group = my_test_tx_group
}

四,java代码说明

1,DruidConfig.java

@Configuration
public class DruidConfig {
/**
* 配置Druid监控
* 后台管理Servlet
* @return
*/
@Bean
public ServletRegistrationBean statViewServlet(){
ServletRegistrationBean bean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");
Map<String,String> initParams = new HashMap<>();//这是配置的druid监控的登录密码
initParams.put("loginUsername","root");
initParams.put("loginPassword","root");
//默认就是允许所有访问
initParams.put("allow","");
initParams.put("deny","192.168.15.21");
//黑名单的IP
bean.setInitParameters(initParams);
return bean;
} /**
* 配置web监控的filter
*/
@Bean
public FilterRegistrationBean webStatFilter(){
FilterRegistrationBean bean = new FilterRegistrationBean();
bean.setFilter(new WebStatFilter());
Map<String,String> initParams = new HashMap<>();
initParams.put("exclusions","/static/*,*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");//过滤掉需要监控的文件
bean.setInitParameters(initParams);
bean.setUrlPatterns(Arrays.asList("/*"));
return bean;
}
}

配置druid

2,SeataConfig.java

@Aspect
@Configuration
public class SeataConfig {
private static final String AOP_POINTCUT_EXPRESSION = "@annotation(io.seata.spring.annotation.GlobalTransactional)"; @Bean
public GlobalTransactionalInterceptor globalTransactionalInterceptor(){
GlobalTransactionalInterceptor globalTransactionalInterceptor = new GlobalTransactionalInterceptor(null);
return globalTransactionalInterceptor;
} @Bean
public Advisor seataAdviceAdvisor() {
AspectJExpressionPointcut pointcut = new AspectJExpressionPointcut();
pointcut.setExpression(AOP_POINTCUT_EXPRESSION);
return new DefaultPointcutAdvisor(pointcut,globalTransactionalInterceptor());
}
}

配置seata

3,SeataFilter.java

@Component
public class SeataFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) servletRequest;
String xid = req.getHeader(RootContext.KEY_XID.toLowerCase());
System.out.println("xid:"+xid);
boolean isBind = false;
if (StringUtils.isNotBlank(xid)) {
//如果xid不为空,则RootContext需要绑定xid,供给seata识别这是同一个分布式事务
RootContext.bind(xid);
isBind = true;
}
try {
filterChain.doFilter(servletRequest, servletResponse);
} finally {
if (isBind) {
RootContext.unbind();
}
}
}
@Override
public void destroy() {
}
}

接收传递的全局事务标志xid

4,GoodsController.java

@RestController
@RequestMapping("/goods")
public class GoodsController { private static final String SUCCESS = "SUCCESS";
private static final String FAIL = "FAIL"; @Resource
private GoodsMapper goodsMapper; //更新商品库存 参数:商品id
@RequestMapping("/goodsstock/{goodsId}/{count}")
@ResponseBody
public String goodsStock(@PathVariable Long goodsId,
@PathVariable int count) { TransactionTypeHolder.set(TransactionType.BASE);
int res = goodsMapper.updateGoodsStock(goodsId,count);
System.out.println("res:"+res); if (res>0) {
return SUCCESS;
} else {
return FAIL;
}
}
//商品详情 参数:商品id
@GetMapping("/goodsinfo")
@ResponseBody
public Goods goodsInfo(@RequestParam(value="goodsid",required = true,defaultValue = "0") Long goodsId) {
Goods goods = goodsMapper.selectOneGoods(goodsId);
return goods;
}
}

5,HomeController.java

@Controller
@RequestMapping("/home")
public class HomeController { private static final String SUCCESS = "SUCCESS";
private static final String FAIL = "FAIL"; @Resource
private OrderShardingMapper orderShardingMapper; @Resource
private GoodsMapper goodsMapper; //订单列表,列出分库分表的数据
@GetMapping("/orderlist")
public String list(Model model, @RequestParam(value="currentPage",required = false,defaultValue = "1") Integer currentPage){
PageHelper.startPage(currentPage, 5);
List<OrderSharding> orderList = orderShardingMapper.selectAllOrder();
model.addAttribute("orderlist",orderList);
PageInfo<OrderSharding> pageInfo = new PageInfo<>(orderList);
model.addAttribute("pageInfo", pageInfo);
System.out.println("------------------------size:"+orderList.size());
return "order/list";
} //添加一个订单,访问一个数据库和分库分表的两个数据库
@GetMapping("/addorder")
@ResponseBody
@GlobalTransactional(timeoutMills = 300000,rollbackFor = Exception.class)
public String addOrder(@RequestParam(value="orderid",required = true,defaultValue = "0") Long orderId,
@RequestParam(value="isfail",required = true,defaultValue = "0") int isFail
) throws SQLException, IOException {
String goodsId = "3";
String goodsNum = "1";
String goodsName = new SimpleDateFormat("yyyyMMddHHmmssSSS").format(new Date());
OrderSharding orderOne = new OrderSharding();
orderOne.setOrderId(orderId);
orderOne.setGoodsName(goodsName);
TransactionTypeHolder.set(TransactionType.BASE);
int resIns = orderShardingMapper.insertOneOrder(orderOne);
System.out.println("orderId:"+orderOne.getOrderId());
TransactionTypeHolder.set(TransactionType.BASE);
int count = -1;
int res = goodsMapper.updateGoodsStock(Long.parseLong(goodsId),count);
System.out.println("res:"+res);
if (isFail == 1) {
int divide = 0;
int resul = 100 / divide;
}
if (res>0) {
return SUCCESS;
} else {
return FAIL;
}
} //添加一个订单,访问一个数据库和分库分表的两个数据库,rest方式
@GetMapping("/addorderrest")
@ResponseBody
@GlobalTransactional(timeoutMills = 300000,rollbackFor = Exception.class)
public String addOrderrest(@RequestParam(value="orderid",required = true,defaultValue = "0") Long orderId,
@RequestParam(value="isfail",required = true,defaultValue = "0") int isFail
) throws SQLException, IOException {
String goodsId = "3";
String goodsNum = "1";
String goodsName = new SimpleDateFormat("yyyyMMddHHmmssSSS").format(new Date());
OrderSharding orderOne = new OrderSharding();
orderOne.setOrderId(orderId);
orderOne.setGoodsName(goodsName);
TransactionTypeHolder.set(TransactionType.BASE);
int resIns = orderShardingMapper.insertOneOrder(orderOne);
System.out.println("orderId:"+orderOne.getOrderId());
RestTemplate restTemplate = new RestTemplate();
String xid = RootContext.getXID();
System.out.println("xid before send:"+xid);
HttpHeaders headers = new HttpHeaders();
headers.add(RootContext.KEY_XID, xid);
String goodsUPNum = "-1";
String urlUpStock = "http://127.0.0.1:8080/goods/goodsstock/"+goodsId+"/"+goodsUPNum+"/";
String resultUp = restTemplate.postForObject(urlUpStock,new HttpEntity<String>(headers),String.class);
if (!SUCCESS.equals(resultUp)) {
throw new RuntimeException();
}
if (isFail == 1) {
int divide = 0;
int resul = 100 / divide;
}
return SUCCESS;
}
}

6,DatabasePreciseShardingAlgorithm.java

@Component
public class DatabasePreciseShardingAlgorithm implements PreciseShardingAlgorithm<Long> {
@Override
public String doSharding(Collection<String> availableTargetNames, PreciseShardingValue<Long> shardingValue) {
System.out.println("------------------select database name");
Long curValue = shardingValue.getValue();
String curBase = "";
if (curValue > 0 && curValue<=200) {
curBase = "saleorder01";
} else {
curBase = "saleorder02";
}
return curBase;
}
}

分库算法

7,OrderTablePreciseShardingAlgorithm.java

@Component
public class OrderTablePreciseShardingAlgorithm implements PreciseShardingAlgorithm<Long> {
@Override
public String doSharding(Collection<String> availableTargetNames, PreciseShardingValue<Long> shardingValue) {
Long curValue = shardingValue.getValue();
String curTable = "";
if (curValue > 0 && curValue<=100) {
curTable = "t_order_1";
} else if (curValue > 100 && curValue<=200) {
curTable = "t_order_2";
} else if (curValue > 200 && curValue<=300) {
curTable = "t_order_3";
} else {
curTable = "t_order_4";
}
return curTable;
}
}

分表算法

8,其他非关键代码可以从github查看

五,测试效果

1,查看shardingjdbc查询数据库的效果:

访问:

http://127.0.0.1:8080/home/orderlist

返回:

可以确定shardingsphere工作正常

2,测试同一个数据源(shardingsphere)不同数据库之间的分布式事务

store库,goods表:设置goodsid为3的商品stock值为100

store库,undolog表的下一个自增值:50

saleorder02库,undo_log表的下一个自增值:39

访问url:

http://127.0.0.1:8080/home/addorder?orderid=400

返回:

SUCCESS

查看数据库:saleorder02库t_order_4表

查看数据库:store库goods表

store库undo_log的自增值:

saleorder02库undo_log的自增值:

可见事务是生效的

测试发生异常时事务的回滚:

访问:

http://127.0.0.1:8080/home/addorder?orderid=401&isfail=1

返回:发生了除0错:

查看数据库:saleorder02:

t_order_4表:

找不到orderid为401的记录

查看undo_log表的下一个自增值:

查看数据库:store:

goods表中查看stock:

未改变

查看undo_log表的下一个自增值:

可见事务已生效:

查看控制台的输出:

可以看到:

Begin new global transaction。。。

Branch Rollbacked result: PhaseTwo_Rollbacked 。。。

Branch Rollbacked result: PhaseTwo_Rollbacked 。。。

有两次rollback,因为提交到了两个库

3,测试通过resttemplate访问url的分布式事务

访问不同url的分布式事务涉及到xid的传递:

可以用以下两个url进行测试,效果同上,不再一一贴出:

http://127.0.0.1:8080/home/addorderrest?orderid=402
http://127.0.0.1:8080/home/addorderrest?orderid=403&isfail=1

4,访问druid的ui,可以看到连接到了3个数据库:

六,查看spring boot的版本:

  .   ____          _            __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.3.3.RELEASE)

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