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Seata业务数据库准备

这里会创建3个服务，一个订单服务，一个库存服务，一个账户服务。

当用户下单时，会在订单服务中创建一个订单，然后通过RPC调用库存服务来扣减下单商品的库存，再通过远程调用账户服务来扣减用户账户里面的余额，最后在订单服务中修改订单状态为已完成。

该操作跨越3个数据库，有两次远程调用，很明显会有分布式事务问题。

创建业务数据库：

• seata_order：存储订单的数据库；
• seata_storage：存储库存的数据库
• seata_account：存储账户信息的数据库

建业务表：

• seata_order库下建t_order表

CREATE TABLE t_order( `id` BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY, `user_id` BIGINT(11) DEFAULT NULL COMMENT '用户id', `product_id` BIGINT(11) DEFAULT NULL COMMENT '产品id', `count` INT(11) DEFAULT NULL COMMENT '数量', `money` DECIMAL(11, 0) DEFAULT NULL COMMENT '金额', `status` INT(1) DEFAULT NULL COMMENT '订单状态：0：创建中；1：已完成')ENGINE=INNODB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;

• seata_storage库下建t_storage表

CREATE TABLE t_storage(	`id` BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,	`product_id` BIGINT(11) DEFAULT NULL COMMENT '产品id',	`total` INT(11) DEFAULT NULL COMMENT '总库存',	`used` INT(11) DEFAULT NULL COMMENT '已用库存',	`residue` INT(11) DEFAULT NULL COMMENT '剩余库存')ENGINE=INNODB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;INSERT INTO t_storage VALUES(1, 1, 100, 0, 100);

• 在seata_account库下建t_account表

CREATE TABLE t_account(	`id` BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT 'id',	`user_id` BIGINT(11) DEFAULT NULL COMMENT '用户id',	`total` DECIMAL(10, 0) DEFAULT NULL COMMENT '总额度',	`used` DECIMAL(10, 0) DEFAULT NULL COMMENT '已用余额',	`residue` DECIMAL(10, 0) DEFAULT '0' COMMENT '剩余可用额度')ENGINE=INNODB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;INSERT INTO t_account VALUES(1, 1, 1000, 0, 1000);

建对应的回滚日志表：

订单、库存、账户3个库下都需要建各自的回滚日志表

-- 此脚本必须初始化在你当前的业务数据库中，用于AT模式XID记录。与server端无关-- 增加唯一索引ux_undo_logCREATE TABLE `undo_log` (  `id` bigint(20) NOT NULL AUTO_INCREMENT,  `branch_id` bigint(20) NOT NULL,  `xid` varchar(100) NOT NULL,  `context` varchar(128) NOT NULL,  `rollback_info` longblob NOT NULL,  `log_status` int(11) NOT NULL,  `log_created` datetime NOT NULL,  `log_modified` datetime NOT NULL,  `ext` varchar(100) DEFAULT NULL,  PRIMARY KEY (`id`),  UNIQUE KEY `ux_undo_log` (`xid`,`branch_id`)) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

订单/库存/账户业务微服务准备

业务需求：下订单 -> 减库存 -> 扣余额 -> 改订单状态

新建Order-Module：

1. seata-order-service2001
2. pom.xml

           
            
                
     
      com.alibaba.cloud
                 
     
      spring-cloud-starter-alibaba-nacos-discovery
             
            
            
                
     
      com.alibaba.cloud
                 
     
      spring-cloud-starter-alibaba-seata
                 
                     
                          
       
        seata-all
                           
       
        io.seata
                       
                  
             
            
                
     
      io.seata
                 
     
      seata-all
                 
     
      1.0.0
             
            
            
                
     
      org.springframework.cloud
                 
     
      spring-cloud-starter-openfeign
             
            
            
                
     
      org.springframework.boot
                 
     
      spring-boot-starter-web
             
            
                
     
      org.springframework.boot
                 
     
      spring-boot-starter-actuator
             
            
            
                
     
      mysql
                 
     
      mysql-connector-java
                 
     
      5.1.37
             
            
                
     
      com.alibaba
                 
     
      druid-spring-boot-starter
                 
     
      1.1.10
             
            
                
     
      org.mybatis.spring.boot
                 
     
      mybatis-spring-boot-starter
                 
     
      2.0.0
             
            
                
     
      org.springframework.boot
                 
     
      spring-boot-starter-test
                 
     
      test
             
            
                
     
      org.projectlombok
                 
     
      lombok
                 
     
      true
             
        
   

3. application.yml

server:  port: 2001spring:  application:    name: seata-order-service  cloud:    alibaba:      seata:        tx-service-group: fsp_tx_group #自定义组名称，需要与seata-server中配置的对应    nacos:      discovery:        server-addr: localhost:8848  datasource:    driver-class-name: com.mysql.jdbc.Driver    url: jdbc:mysql://localhost:3306/seata_order    username: root    password: 123456feign:  hystrix:    enabled: falselogging:  level:     io:      seata: info      mybatis:  mapperLocations: classpath:mapper/*.xml

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  }  shutdown {    # when destroy server, wait seconds    wait = 3  }  serialization = "seata"  compressor = "none"}service {  vgroup_mapping.fsp_tx_group = "default" #修改自定义事务组名称  default.grouplist = "127.0.0.1:8091"  enableDegrade = false  disable = false  max.commit.retry.timeout = "-1"  max.rollback.retry.timeout = "-1"  disableGlobalTransaction = false}client {  async.commit.buffer.limit = 10000  lock {    retry.internal = 10    retry.times = 30  }  report.retry.count = 5  tm.commit.retry.count = 1  tm.rollback.retry.count = 1}## transaction log storestore {  ## store mode: file、db  mode = "db"  ## file store  file {    dir = "sessionStore"    # branch session size , if exceeded first try compress lockkey, still exceeded throws exceptions    max-branch-session-size = 16384    # globe session size , if exceeded throws exceptions    max-global-session-size = 512    # file buffer size , if exceeded allocate new buffer    file-write-buffer-cache-size = 16384    # when recover batch read size    session.reload.read_size = 100    # async, sync    flush-disk-mode = async  }  ## database store  db {    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.    datasource = "dbcp"    ## mysql/oracle/h2/oceanbase etc.    db-type = "mysql"    driver-class-name = "com.mysql.jdbc.Driver"    url = "jdbc:mysql://127.0.0.1:3306/seata"    user = "root"    password = "123456"    min-conn = 1    max-conn = 3    global.table = "global_table"    branch.table = "branch_table"    lock-table = "lock_table"    query-limit = 100  }}lock {  ## the lock store mode: local、remote  mode = "remote"  local {    ## store locks in user's database  }  remote {    ## store locks in the seata's server  }}recovery {  #schedule committing retry period in milliseconds  committing-retry-period = 1000  #schedule asyn committing retry period in milliseconds  asyn-committing-retry-period = 1000  #schedule rollbacking retry period in milliseconds  rollbacking-retry-period = 1000  #schedule timeout retry period in milliseconds  timeout-retry-period = 1000}transaction {  undo.data.validation = true  undo.log.serialization = "jackson"  undo.log.save.days = 7  #schedule delete expired undo_log in milliseconds  undo.log.delete.period = 86400000  undo.log.table = "undo_log"}## metrics settingsmetrics {  enabled = false  registry-type = "compact"  # multi exporters use comma divided  exporter-list = "prometheus"  exporter-prometheus-port = 9898}support {  ## spring  spring {    # auto proxy the DataSource bean    datasource.autoproxy = false  }}

5. registry.conf

registry {  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa  type = "nacos"  nacos {    serverAddr = "localhost:8848"    namespace = ""    cluster = "default"  }  eureka {    serviceUrl = "http://localhost:8761/eureka"    application = "default"    weight = "1"  }  redis {    serverAddr = "localhost:6379"    db = "0"  }  zk {    cluster = "default"    serverAddr = "127.0.0.1:2181"    session.timeout = 6000    connect.timeout = 2000  }  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 = "localhost"    namespace = ""  }  consul {    serverAddr = "127.0.0.1:8500"  }  apollo {    app.id = "seata-server"    apollo.meta = "http://192.168.1.204:8801"  }  zk {    serverAddr = "127.0.0.1:2181"    session.timeout = 6000    connect.timeout = 2000  }  etcd3 {    serverAddr = "http://localhost:2379"  }  file {    name = "file.conf"  }}

6. domain

@Data@AllArgsConstructor@NoArgsConstructorpublic class Order {
           private Long id;    private Long userId;    private Long productId;    private Integer count;    private BigDecimal money;        /*        订单状态： 0：创建中；1：已完成；     */    private Integer status;}

@Data@AllArgsConstructor@NoArgsConstructorpublic class CommonResult
   
     {
           private Integer code;    private String message;    private T data;        public CommonResult(Integer code, String message){
           this(code, message, null);    }}
   

7. Dao接口及实现

@Mapperpublic interface OrderDao {
       //新建订单    void create(Order order);    //修改订单状态 0 -> 1    void update(@Param("userId") Long userId, @Param("status") Integer status);}

   
       
            
             
             
             
             
             
         
        
    
             insert into t_order (id,user_id,product_id,count,money,status)        values (null,#{userId},#{productId},#{count},#{money},0);    
        
    
             update t_order set status = 1        where user_id=#{userId} and status = #{status};    
    
   

8. Service接口及实现

public interface OrderService {
       //创建订单    void create(Order order);}

@Service@Slf4jpublic class OrderServiceImpl implements OrderService {
       @Resource    OrderDao orderDao;    @Resource    StorageService storageService;    @Resource    AccountService accountService;    @Override    public void create(Order order) {
           log.info("------>开始新建订单");        orderDao.create(order);        log.info("------>订单微服务开始调用库存，扣减count");        storageService.decrease(order.getProductId(), order.getCount());        log.info("------>订单微服务开始调用库存，扣减end");        log.info("------>订单微服务开始调用账户，扣减money");        accountService.decrease(order.getUserId(), order.getMoney());        log.info("------>订单微服务开始调用账户，扣减end");        log.info("------>开始修改订单状态");        orderDao.update(order.getUserId(), 0);        log.info("------>修改订单状态完毕");        log.info("------>下单完毕");    }}

@FeignClient(value = "seata-account-service")public interface AccountService {
       //扣减账户余额    @PostMapping(value = "/account/decrease")    CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);}

@FeignClient(value = "seata-storage-service")public interface StorageService {
       //扣减库存    @PostMapping(value = "/storage/decrease")    CommonResult decrease(@RequestParam("productId") Long productId, @RequestParam("count") Integer count);}

9. Controller

@RestControllerpublic class OrderController{
       @Resource    OrderService orderService;    @GetMapping("/order/create")    public CommonResult create(Order order) {
           orderService.create(order);        return new CommonResult(200,"订单创建成功");    }}

10. Config配置

@Configuration@MapperScan({
   "pers.zhang.springcloud.alibaba.dao"})public class MyBatisConfig {
   }

@Configurationpublic class DataSourceProxyConfig {
       @Value("${mybatis.mapperLocations}")    private String mapperLocations;    @Bean    @ConfigurationProperties(prefix = "spring.datasource")    public DataSource druidDataSource(){
           return new DruidDataSource();    }    @Bean    public DataSourceProxy dataSourceProxy(DataSource dataSource) {
           return new DataSourceProxy(dataSource);    }    @Bean    public SqlSessionFactory sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
           SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();        sqlSessionFactoryBean.setDataSource(dataSourceProxy);        sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));        sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());        return sqlSessionFactoryBean.getObject();    }}

11. 主启动类

@EnableFeignClients@EnableDiscoveryClient@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)//取消数据源自动创建public class SeataOrderMainApp2001 {
       public static void main(String[] args) {
           SpringApplication.run(SeataOrderMainApp2001.class, args);    }}

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