【第36章】Spring Cloud之Seata分布式事务

news2024/9/24 23:28:26

文章目录

  • 前言
  • 一、架构图
    • 1. 介绍
    • 2. 项目结构
    • 3. 功能描述
  • 二、用例
    • 1. 准备
      • 1.1 系统表
      • 1.2 业务表
      • 1.3 初始化数据
    • 2. 项目搭建
      • 2.1 项目结构
      • 2.2 主要依赖
      • 2.3 主要配置
  • 三、主要业务代码
    • 1. 仓储服务
      • 1.1 controller
      • 1.2 service
      • 1.3 dao
    • 2. 订单服务
      • 1.1 controller
      • 1.2 service
      • 1.3 dao
    • 3. 帐户服务
      • 1.1 controller
      • 1.2 service
      • 1.3 dao
    • 4. 商品服务
      • 1.1 controller
      • 1.2 service
      • 1.3 rest
  • 四、业务单元测试
    • 1. 准备
    • 2. 成功测试
      • 2.1 结果
      • 2.2 日志
    • 3. 失败测试
      • 3.1 数据重置
      • 3.2 结果
      • 3.3 日志
      • 3.4 控制台
  • 总结

前言

上一章我们已经搭建好了Seata服务端，这里我们根据官方案例来完成分布式事务。

一、架构图

1. 介绍

在这里插入图片描述
我们以传统电商购物系统作为案例，我们有4个服务分别是

  • Business(商品服务)
  • Storage(仓储服务)
  • Order(订单服务)
  • Account(帐户服务)

2. 项目结构

seata-server负责管理Maven依赖及版本管理，4个子SpringBoot服务，负责各自的职责，共同完成整个下单的流程。

在这里插入图片描述

3. 功能描述

这里我们主要使用openfeign(服务调用)+mybatis(数据存储),使用Seata的AT模式完成分布式事务。

二、用例

1. 准备

1.1 系统表

Seata AT 模式 需要使用到 undo_log 表。

CREATE TABLE IF NOT EXISTS `undo_log`
(
    `branch_id`     BIGINT       NOT NULL COMMENT 'branch transaction id',
    `xid`           VARCHAR(128) NOT NULL COMMENT 'global transaction id',
    `context`       VARCHAR(128) NOT NULL COMMENT 'undo_log context,such as serialization',
    `rollback_info` LONGBLOB     NOT NULL COMMENT 'rollback info',
    `log_status`    INT(11)      NOT NULL COMMENT '0:normal status,1:defense status',
    `log_created`   DATETIME(6)  NOT NULL COMMENT 'create datetime',
    `log_modified`  DATETIME(6)  NOT NULL COMMENT 'modify datetime',
    UNIQUE KEY `ux_undo_log` (`xid`, `branch_id`)
    ) ENGINE = InnoDB AUTO_INCREMENT = 1 DEFAULT CHARSET = utf8mb4 COMMENT ='AT transaction mode undo table';
ALTER TABLE `undo_log` ADD INDEX `ix_log_created` (`log_created`);

1.2 业务表

CREATE TABLE IF NOT EXISTS  `storage_tbl` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `commodity_code` varchar(255) DEFAULT NULL,
  `count` int(11) DEFAULT 0,
  PRIMARY KEY (`id`),
  UNIQUE KEY (`commodity_code`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

CREATE TABLE IF NOT EXISTS  `order_tbl` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` varchar(255) DEFAULT NULL,
  `commodity_code` varchar(255) DEFAULT NULL,
  `count` int(11) DEFAULT 0,
  `money` int(11) DEFAULT 0,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

CREATE TABLE IF NOT EXISTS  `account_tbl` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` varchar(255) DEFAULT NULL,
  `money` int(11) DEFAULT 0,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1  DEFAULT CHARSET=utf8;

1.3 初始化数据

delete from account_tbl;
delete from order_tbl;
delete from storage_tbl;
insert into account_tbl(user_id,money) values('U100001','10000');
insert into storage_tbl(commodity_code,count) values('C00321','100');

2. 项目搭建

这里我们主要以账户服务为主，内容过多其他内容不便演示

2.1 项目结构

在这里插入图片描述

2.2 主要依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
</dependency>
<dependency>
    <groupId>com.mysql</groupId>
    <artifactId>mysql-connector-j</artifactId>
</dependency>
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-loadbalancer</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>

2.3 主要配置

应用配置(application.yml)

base:
  config:
    mdb:
      hostname: 127.0.0.1 #your mysql server ip address
      dbname: seata #your database name for test
      port: 3306 #your mysql server listening port
      username: seata #your mysql server username
      password: seata #your mysql server password
server:
  port: 18084
spring:
  application:
    name: account-service
  main:
    allow-bean-definition-overriding: true
  cloud:
    nacos:
      discovery:
        server-addr: ${NACOS_SERVER_ADDR}
        namespace: ${NACOS_NAMESPACE}
        username: ${NACOS_USERNAME}
        password: ${NACOS_PASSWORD}
        group: SEATA_GROUP
  datasource:
    name: storageDataSource
    #    druid don't support GraalVM now because of there is CGlib proxy
    #    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://${base.config.mdb.hostname}:${base.config.mdb.port}/${base.config.mdb.dbname}?useSSL=false&serverTimezone=UTC
    username: ${base.config.mdb.username}
    password: ${base.config.mdb.password}
#    druid:
#      max-active: 20
#      min-idle: 2
#      initial-size: 2
seata:
  enabled: true
  application-id: ${spring.application.name}
#  高可用:应用级别的控制,可动态切换
#  tx-service-group: ${spring.application.name}-tx-group
  tx-service-group: default_tx_group
  config:
    type: nacos
    nacos:
      dataId: "seata-client.yaml"
      server-addr: ${NACOS_SERVER_ADDR}
      namespace: ${NACOS_NAMESPACE}
      username: ${NACOS_USERNAME}
      password: ${NACOS_PASSWORD}
  registry:
    type: nacos
    nacos:
      server-addr: ${NACOS_SERVER_ADDR}
      namespace: ${NACOS_NAMESPACE}
      username: ${NACOS_USERNAME}
      password: ${NACOS_PASSWORD}
      group: SEATA_GROUP
mybatis:
  mapper-locations: classpath:mapper/*.xml
  configuration:
    map-underscore-to-camel-case: true

客户端配置(seata-client.yaml)

seata:
  enabled: true
  application-id: applicationName
  tx-service-group: default_tx_group
  enable-auto-data-source-proxy: true
  data-source-proxy-mode: AT
  use-jdk-proxy: false
  scan-packages: firstPackage,secondPackage
  excludes-for-scanning: firstBeanNameForExclude,secondBeanNameForExclude
  excludes-for-auto-proxying: firstClassNameForExclude,secondClassNameForExclude
  client:
    rm:
      async-commit-buffer-limit: 10000
      report-retry-count: 5
      table-meta-check-enable: false
      report-success-enable: false
      saga-branch-register-enable: false
      saga-json-parser: fastjson
      saga-retry-persist-mode-update: false
      saga-compensate-persist-mode-update: false
      tcc-action-interceptor-order: -2147482648 #Ordered.HIGHEST_PRECEDENCE + 1000
      sql-parser-type: druid
      lock:
        retry-interval: 10
        retry-times: 30
        retry-policy-branch-rollback-on-conflict: true
    tm:
      commit-retry-count: 5
      rollback-retry-count: 5
      default-global-transaction-timeout: 60000
      degrade-check: false
      degrade-check-period: 2000
      degrade-check-allow-times: 10
      interceptor-order: -2147482648 #Ordered.HIGHEST_PRECEDENCE + 1000
    undo:
      data-validation: true
      log-serialization: jackson
      log-table: undo_log
      only-care-update-columns: true
      compress:
        enable: true
        type: zip
        threshold: 64k
    load-balance:
      type: XID
      virtual-nodes: 10
  service:
    vgroup-mapping:
      default_tx_group: default
    grouplist:
      default: 192.168.145.128:8091
    enable-degrade: false
    disable-global-transaction: false      
  transport:
    shutdown:
      wait: 3
    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
      worker-thread-size: default
      boss-thread-size: 1
    type: TCP
    server: NIO
    heartbeat: true
    serialization: seata
    compressor: none
    enable-tm-client-batch-send-request: false
    enable-rm-client-batch-send-request: true
    rpc-rm-request-timeout: 15000
    rpc-tm-request-timeout: 30000
  log:
    exception-rate: 100
  tcc:
    fence:
      log-table-name: tcc_fence_log
      clean-period: 1h
  saga:
    enabled: false
    state-machine:
      table-prefix: seata_
      enable-async: false
      async-thread-pool:
        core-pool-size: 1
        max-pool-size: 20
        keep-alive-time: 60
      trans-operation-timeout: 1800000
      service-invoke-timeout: 300000
      auto-register-resources: true
      resources:
        - classpath*:seata/saga/statelang/**/*.json
      default-tenant-id: 000001
      charset: UTF-8

事务分组配置(service.vgroupMapping.default_tx_group)

default

更多配置请参考官方脚本

三、主要业务代码

1. 仓储服务

1.1 controller

package org.example.storage.controller;

import io.seata.core.context.RootContext;
import org.example.storage.service.StorageService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/storage")
public class StorageController {

	private static final Logger LOGGER = LoggerFactory.getLogger(StorageController.class);

	private static final String SUCCESS = "SUCCESS";

	private static final String FAIL = "FAIL";
	@Autowired
	private StorageService storageService;

	@GetMapping(value = "/deduct/{commodityCode}/{count}", produces = "application/json")
	public String deduct(@PathVariable("commodityCode") String commodityCode, @PathVariable("count") int count) {
		LOGGER.info("Storage Service Begin ... xid: " + RootContext.getXID());
		int result = storageService.deduct(commodityCode, count);
		LOGGER.info("Storage Service End ... ");
		if (result == 1) {
			return SUCCESS;
		}
		return FAIL;
	}

}

1.2 service

package org.example.storage.service;

public interface StorageService {

    /**
     * 扣减库存
     *
     * @param commodityCode 商品编号
     * @param count         扣减数量
     * @return result   执行结果
     */
    int deduct(String commodityCode, int count);
}


package org.example.storage.service.impl;

import io.seata.core.context.RootContext;
import org.example.storage.dao.StorageMapper;
import org.example.storage.model.Storage;
import org.example.storage.service.StorageService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;

@Service
public class StorageServiceImpl implements StorageService {

    private static final Logger LOGGER = LoggerFactory.getLogger(StorageService.class);

    @Resource
    private StorageMapper storageMapper;

    @Override
    public int deduct(String commodityCode, int count) {
        LOGGER.info("Stock Service Begin ... xid: " + RootContext.getXID());
        LOGGER.info("Deducting inventory SQL: update stock_tbl set count = count - {} where commodity_code = {}", count,
                commodityCode);
        Storage stock = storageMapper.findByCommodityCode(commodityCode);
        stock.setCount(stock.getCount() - count);
        int result = storageMapper.updateById(stock);
        LOGGER.info("Stock Service End ... ");
        return result;
    }

}

1.3 dao

package org.example.storage.dao;

import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.example.storage.model.Storage;
import org.springframework.stereotype.Repository;

import java.util.List;

@Mapper
@Repository
public interface StorageMapper {

    Storage selectById(@Param("id") Integer id);

    Storage findByCommodityCode(@Param("commodityCode") String commodityCode);

    int updateById(Storage record);

    void insert(Storage record);

    void insertBatch(List<Storage> records);

    int updateBatch(@Param("list") List<Long> ids, @Param("commodityCode") String commodityCode);
}

2. 订单服务

1.1 controller

package org.example.order.controller;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Random;

import io.seata.core.context.RootContext;
import org.example.order.service.OrderService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCreator;
import org.springframework.jdbc.support.GeneratedKeyHolder;
import org.springframework.jdbc.support.KeyHolder;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
@RequestMapping("/order")
public class OrderController {

	private static final Logger LOGGER = LoggerFactory.getLogger(OrderController.class);

	private static final String SUCCESS = "SUCCESS";

	private static final String FAIL = "FAIL";

	@Autowired
	private OrderService orderService;

	@PostMapping(value = "/create", produces = "application/json")
	public String create(@RequestParam("userId") String userId,@RequestParam("commodityCode") String commodityCode,@RequestParam("orderCount") int orderCount) {
		LOGGER.info("Order Service Begin ... xid: " + RootContext.getXID());
		int result = orderService.create(userId, commodityCode, orderCount);
		LOGGER.info("Order Service End ... Created " + result);
		if (result == 2) {
			return SUCCESS;
		}
		return FAIL;
	}

}

1.2 service

package org.example.order.service;


public interface OrderService {

    /**
     * 创建订单
     *
     * @param userId        用户ID
     * @param commodityCode 商品编号
     * @param orderCount    订购数量
     * @return result   执行结果
     */
    int create(String userId, String commodityCode, int orderCount);
}


package org.example.order.service.impl;

import org.example.order.dao.OrderMapper;
import org.example.order.feign.AccountService;
import org.example.order.model.Order;
import org.example.order.service.OrderService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;

@Service
public class OrderServiceImpl implements OrderService {

    private static final Logger LOGGER = LoggerFactory.getLogger(OrderService.class);

    private static final String SUCCESS = "SUCCESS";

    @Resource
    private AccountService accountService;
    @Resource
    private OrderMapper orderMapper;

    @Override
    public int create(String userId, String commodityCode, int count) {
        int result=0;
        Order order = new Order();
        order.setUserId(userId);
        order.setCommodityCode(commodityCode);
        order.setCount(count);
        int orderMoney = calculate(count);
        order.setMoney(orderMoney);
        //保存订单
        result+=orderMapper.insert(order);
        //扣减余额
        if(SUCCESS.equalsIgnoreCase(accountService.debit(userId, orderMoney))){
            result+=1;
        }
        return result;
    }

    private int calculate(int count) {
        return 200 * count;
    }

}

1.3 dao

package org.example.order.dao;


import org.apache.ibatis.annotations.Mapper;
import org.example.order.model.Order;
import org.springframework.stereotype.Repository;

@Mapper
@Repository
public interface OrderMapper {

    int insert(Order record);

}

3. 帐户服务

1.1 controller

package org.example.account.controller;

import io.seata.core.context.RootContext;
import org.example.account.service.AccountService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/account")
public class AccountController {

	private static final Logger LOGGER = LoggerFactory.getLogger(AccountController.class);

	private static final String SUCCESS = "SUCCESS";

	private static final String FAIL = "FAIL";
	@Autowired
	private AccountService accountService;

	@PostMapping(value = "/debit", produces = "application/json")
	public String debit(@RequestParam("userId") String userId,@RequestParam("money") int money) {
		LOGGER.info("Account Service ... xid: " + RootContext.getXID());
		int result = accountService.debit(userId, money);
		LOGGER.info("Account Service End ... ");
		if (result == 1) {
			return SUCCESS;
		}
		return FAIL;
	}

}

1.2 service

package org.example.account.service;

public interface AccountService {

    /**
     * 余额扣款
     *
     * @param userId 用户ID
     * @param money  扣款金额
     * @return result 处理结果
     */
    int debit(String userId, int money);
}


package org.example.account.service.impl;

import org.example.account.dao.AccountMapper;
import org.example.account.model.Account;
import org.example.account.service.AccountService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;

@Service
public class AccountServiceImpl implements AccountService {

    private static final Logger LOGGER = LoggerFactory.getLogger(AccountService.class);

    @Resource
    private AccountMapper accountMapper;

    @Override
    public int debit(String userId, int money) {
        LOGGER.info("Deducting balance SQL: update account_tbl set money = money - {} where user_id = {}", money,
                userId);
        Account account = accountMapper.selectByUserId(userId);
        account.setMoney(money);
        return accountMapper.updateById(account);
    }
}

1.3 dao

package org.example.account.dao;

import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.example.account.model.Account;
import org.springframework.stereotype.Repository;

@Mapper
@Repository
public interface AccountMapper {

    Account selectByUserId(@Param("userId") String userId);

    int updateById(Account record);

}

4. 商品服务

商品服务包含了rest和feign两种请求方式

1.1 controller

package org.example.business.controller;

import io.seata.spring.annotation.GlobalTransactional;
import org.example.business.feign.OrderService;
import org.example.business.feign.StorageService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

@RestController
public class BusinessController {

	private static final Logger LOGGER = LoggerFactory.getLogger(BusinessController.class);

	private static final String SUCCESS = "SUCCESS";

	private static final String FAIL = "FAIL";

	private static final String USER_ID = "U100001";

	private static final String COMMODITY_CODE = "C00321";

	private static final int ORDER_COUNT = 2;
	@Autowired
	private RestTemplate restTemplate;
	@Autowired
	private OrderService orderService;
	@Autowired
	private StorageService storageService;
	@GlobalTransactional(timeoutMills = 300000, name = "spring-cloud-demo-tx")
	@GetMapping(value = "/seata/rest", produces = "application/json")
	public String rest() {
		String result = restTemplate.getForObject("http://storage-service/storage/deduct/" + COMMODITY_CODE + "/" + ORDER_COUNT,
				String.class);
		if (!SUCCESS.equals(result)) {
			throw new RuntimeException();
		}
		String url = "http://order-service/order/create";
		HttpHeaders headers = new HttpHeaders();
		headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);
		MultiValueMap<String, String> map = new LinkedMultiValueMap<String, String>();
		map.add("userId", USER_ID);
		map.add("commodityCode", COMMODITY_CODE);
		map.add("orderCount", ORDER_COUNT + "");
		HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<MultiValueMap<String, String>>(map, headers);
		ResponseEntity<String> response;
		try {
			response = restTemplate.postForEntity(url, request, String.class);
		}catch (Exception exx) {
			throw new RuntimeException("mock error");
		}
		result = response.getBody();
		if (!SUCCESS.equals(result)) {
			throw new RuntimeException();
		}
		return SUCCESS;
	}

	@GlobalTransactional(timeoutMills = 300000, name = "spring-cloud-demo-tx")
	@GetMapping(value = "/seata/feign", produces = "application/json")
	public String feign() {
		String result = storageService.deduct(COMMODITY_CODE, ORDER_COUNT);
		if (!SUCCESS.equals(result)) {
			throw new RuntimeException();
		}
		result = orderService.create(USER_ID, COMMODITY_CODE, ORDER_COUNT);
		if (!SUCCESS.equals(result)) {
			throw new RuntimeException();
		}
		return SUCCESS;

	}

}

1.2 service

package org.example.business.feign;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;

@FeignClient(name = "storage-service")
public interface StorageService {

    /**
     * 扣减库存
     *
     * @param commodityCode 商品编号
     * @param count         扣减数量
     * @return result   执行结果
     */
    @GetMapping(value = "/storage/deduct/{commodityCode}/{count}")
    String deduct(@PathVariable("commodityCode") String commodityCode, @PathVariable("count") int count);
}


package org.example.business.feign;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;

@FeignClient(name = "order-service")
public interface OrderService {

    /**
     * 创建订单
     *
     * @param userId        用户ID
     * @param commodityCode 商品编号
     * @param orderCount    订购数量
     * @return result   执行结果
     */
    @PostMapping(value = "/order/create")
    String create(@RequestParam("userId") String userId,@RequestParam("commodityCode") String commodityCode,@RequestParam("orderCount") int orderCount);
}

1.3 rest

package org.example.business.config;

import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

/**
 * Create by zjg on 2024/9/15
 */
@Configuration
public class BusinessConfig {
    @Bean
    @LoadBalanced
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }
}

四、业务单元测试

1. 准备

首先启动我们的服务，并保证服务正常注册到Nacos

在这里插入图片描述
在这里插入图片描述

2. 成功测试

2.1 结果

localhost:18081/seata/feign
在这里插入图片描述
在这里插入图片描述

2.2 日志

我们每个服务都能从上下文中获取到xid

2024-09-15T21:37:32.765+08:00  INFO 10488 --- [business-service] [io-18081-exec-9] i.seata.tm.api.DefaultGlobalTransaction  : Begin new global transaction [192.168.145.128:8091:2162292867793093336]
2024-09-15T21:37:32.977+08:00  INFO 10488 --- [business-service] [io-18081-exec-9] i.seata.tm.api.DefaultGlobalTransaction  : transaction 192.168.145.128:8091:2162292867793093336 will be commit
2024-09-15T21:37:32.984+08:00  INFO 10488 --- [business-service] [io-18081-exec-9] i.seata.tm.api.DefaultGlobalTransaction  : transaction end, xid = 192.168.145.128:8091:2162292867793093336
2024-09-15T21:37:32.984+08:00  INFO 10488 --- [business-service] [io-18081-exec-9] i.seata.tm.api.DefaultGlobalTransaction  : [192.168.145.128:8091:2162292867793093336] commit status: Committed

2024-09-15T21:37:32.768+08:00  INFO 4560 --- [storage-service] [io-18082-exec-5] o.e.s.controller.StorageController       : Storage Service Begin ... xid: 192.168.145.128:8091:2162292867793093336
2024-09-15T21:37:32.769+08:00  INFO 4560 --- [storage-service] [io-18082-exec-5] o.e.storage.service.StorageService       : Stock Service Begin ... xid: 192.168.145.128:8091:2162292867793093336
2024-09-15T21:37:32.769+08:00  INFO 4560 --- [storage-service] [io-18082-exec-5] o.e.storage.service.StorageService       : Deducting inventory SQL: update stock_tbl set count = count - 2 where commodity_code = C00321
2024-09-15T21:37:32.777+08:00  INFO 4560 --- [storage-service] [io-18082-exec-5] io.seata.rm.AbstractResourceManager      : branch register success, xid:192.168.145.128:8091:2162292867793093336, branchId:2162292867793093338, lockKeys:storage_tbl:1
2024-09-15T21:37:32.781+08:00  INFO 4560 --- [storage-service] [io-18082-exec-5] o.e.storage.service.StorageService       : Stock Service End ... 
2024-09-15T21:37:32.781+08:00  INFO 4560 --- [storage-service] [io-18082-exec-5] o.e.s.controller.StorageController       : Storage Service End ... 
2024-09-15T21:37:33.600+08:00  INFO 4560 --- [storage-service] [h_RMROLE_1_7_16] i.s.c.r.p.c.RmBranchCommitProcessor      : rm client handle branch commit process:BranchCommitRequest{xid='192.168.145.128:8091:2162292867793093336', branchId=2162292867793093338, branchType=AT, resourceId='jdbc:mysql://192.168.145.128:3306/seata', applicationData='null'}
2024-09-15T21:37:33.601+08:00  INFO 4560 --- [storage-service] [h_RMROLE_1_7_16] io.seata.rm.AbstractRMHandler            : Branch committing: 192.168.145.128:8091:2162292867793093336 2162292867793093338 jdbc:mysql://192.168.145.128:3306/seata null
2024-09-15T21:37:33.601+08:00  INFO 4560 --- [storage-service] [h_RMROLE_1_7_16] io.seata.rm.AbstractRMHandler            : Branch commit result: PhaseTwo_Committed

2024-09-15T21:37:32.785+08:00  INFO 11676 --- [order-service] [io-18083-exec-9] o.e.order.controller.OrderController     : Order Service Begin ... xid: 192.168.145.128:8091:2162292867793093336
2024-09-15T21:37:32.796+08:00  INFO 11676 --- [order-service] [io-18083-exec-9] io.seata.rm.AbstractResourceManager      : branch register success, xid:192.168.145.128:8091:2162292867793093336, branchId:2162292867793093340, lockKeys:order_tbl:2
2024-09-15T21:37:32.975+08:00  INFO 11676 --- [order-service] [io-18083-exec-9] o.e.order.controller.OrderController     : Order Service End ... Created 2
2024-09-15T21:37:33.695+08:00  INFO 11676 --- [order-service] [h_RMROLE_1_7_16] i.s.c.r.p.c.RmBranchCommitProcessor      : rm client handle branch commit process:BranchCommitRequest{xid='192.168.145.128:8091:2162292867793093336', branchId=2162292867793093340, branchType=AT, resourceId='jdbc:mysql://192.168.145.128:3306/seata', applicationData='null'}
2024-09-15T21:37:33.695+08:00  INFO 11676 --- [order-service] [h_RMROLE_1_7_16] io.seata.rm.AbstractRMHandler            : Branch committing: 192.168.145.128:8091:2162292867793093336 2162292867793093340 jdbc:mysql://192.168.145.128:3306/seata null
2024-09-15T21:37:33.695+08:00  INFO 11676 --- [order-service] [h_RMROLE_1_7_16] io.seata.rm.AbstractRMHandler            : Branch commit result: PhaseTwo_Committed

2024-09-15T21:37:32.803+08:00  INFO 12564 --- [account-service] [io-18084-exec-5] o.e.a.controller.AccountController       : Account Service ... xid: 192.168.145.128:8091:2162292867793093336
2024-09-15T21:37:32.803+08:00  INFO 12564 --- [account-service] [io-18084-exec-5] o.e.account.service.AccountService       : Deducting balance SQL: update account_tbl set money = money - 400 where user_id = U100001
2024-09-15T21:37:32.970+08:00  INFO 12564 --- [account-service] [io-18084-exec-5] io.seata.rm.AbstractResourceManager      : branch register success, xid:192.168.145.128:8091:2162292867793093336, branchId:2162292867793093342, lockKeys:account_tbl:1
2024-09-15T21:37:32.973+08:00  INFO 12564 --- [account-service] [io-18084-exec-5] o.e.a.controller.AccountController       : Account Service End ... 
2024-09-15T21:37:33.697+08:00  INFO 12564 --- [account-service] [h_RMROLE_1_7_16] i.s.c.r.p.c.RmBranchCommitProcessor      : rm client handle branch commit process:BranchCommitRequest{xid='192.168.145.128:8091:2162292867793093336', branchId=2162292867793093342, branchType=AT, resourceId='jdbc:mysql://192.168.145.128:3306/seata', applicationData='null'}
2024-09-15T21:37:33.698+08:00  INFO 12564 --- [account-service] [h_RMROLE_1_7_16] io.seata.rm.AbstractRMHandler            : Branch committing: 192.168.145.128:8091:2162292867793093336 2162292867793093342 jdbc:mysql://192.168.145.128:3306/seata null
2024-09-15T21:37:33.698+08:00  INFO 12564 --- [account-service] [h_RMROLE_1_7_16] io.seata.rm.AbstractRMHandler            : Branch commit result: PhaseTwo_Committed

3. 失败测试

失败的案例怎么做呢？简单，帐户服务作为作为购物生命周期的最后一环，我们在账户服务产生异常即可

3.1 数据重置

truncate table account_tbl;
truncate table order_tbl;
truncate table storage_tbl;
insert into account_tbl(user_id,money) values('U100001','10000');
insert into storage_tbl(commodity_code,count) values('C00321','100');

3.2 结果

localhost:18081/seata/rest
在这里插入图片描述
在这里插入图片描述

可以看到我们的数据是没有发生变化的

3.3 日志

此处日志过多，仅剪辑关键部分

2024-09-15T21:58:20.193+08:00  INFO 10488 --- [business-service] [io-18081-exec-6] i.seata.tm.api.DefaultGlobalTransaction  : Begin new global transaction [192.168.145.128:8091:2162292867793093649]
2024-09-15T21:58:20.331+08:00  INFO 10488 --- [business-service] [io-18081-exec-6] i.seata.tm.api.DefaultGlobalTransaction  : transaction 192.168.145.128:8091:2162292867793093649 will be rollback
2024-09-15T21:58:20.381+08:00  INFO 10488 --- [business-service] [io-18081-exec-6] i.seata.tm.api.DefaultGlobalTransaction  : transaction end, xid = 192.168.145.128:8091:2162292867793093649
2024-09-15T21:58:20.381+08:00  INFO 10488 --- [business-service] [io-18081-exec-6] i.seata.tm.api.DefaultGlobalTransaction  : [192.168.145.128:8091:2162292867793093649] rollback status: Rollbacked
2024-09-15T21:58:20.381+08:00 ERROR 10488 --- [business-service] [io-18081-exec-6] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: java.lang.RuntimeException: try to proceed invocation error] with root cause
java.lang.RuntimeException: mock error
	at org.example.business.controller.BusinessController.rest(BusinessController.java:59) ~[classes/:na]

2024-09-15T21:58:20.195+08:00  INFO 4560 --- [storage-service] [io-18082-exec-8] o.e.s.controller.StorageController       : Storage Service Begin ... xid: 192.168.145.128:8091:2162292867793093649
2024-09-15T21:58:20.195+08:00  INFO 4560 --- [storage-service] [io-18082-exec-8] o.e.storage.service.StorageService       : Stock Service Begin ... xid: 192.168.145.128:8091:2162292867793093649
2024-09-15T21:58:20.195+08:00  INFO 4560 --- [storage-service] [io-18082-exec-8] o.e.storage.service.StorageService       : Deducting inventory SQL: update stock_tbl set count = count - 2 where commodity_code = C00321
2024-09-15T21:58:20.204+08:00  INFO 4560 --- [storage-service] [io-18082-exec-8] io.seata.rm.AbstractResourceManager      : branch register success, xid:192.168.145.128:8091:2162292867793093649, branchId:2162292867793093651, lockKeys:storage_tbl:1
2024-09-15T21:58:20.207+08:00  INFO 4560 --- [storage-service] [io-18082-exec-8] o.e.storage.service.StorageService       : Stock Service End ... 
2024-09-15T21:58:20.207+08:00  INFO 4560 --- [storage-service] [io-18082-exec-8] o.e.s.controller.StorageController       : Storage Service End ... 
2024-09-15T21:58:20.337+08:00  INFO 4560 --- [storage-service] [_RMROLE_1_14_16] i.s.c.r.p.c.RmBranchRollbackProcessor    : rm handle branch rollback process:BranchRollbackRequest{xid='192.168.145.128:8091:2162292867793093649', branchId=2162292867793093651, branchType=AT, resourceId='jdbc:mysql://192.168.145.128:3306/seata', applicationData='null'}
2024-09-15T21:58:20.337+08:00  INFO 4560 --- [storage-service] [_RMROLE_1_14_16] io.seata.rm.AbstractRMHandler            : Branch Rollbacking: 192.168.145.128:8091:2162292867793093649 2162292867793093651 jdbc:mysql://192.168.145.128:3306/seata
2024-09-15T21:58:20.344+08:00  INFO 4560 --- [storage-service] [_RMROLE_1_14_16] i.s.r.d.undo.AbstractUndoLogManager      : xid 192.168.145.128:8091:2162292867793093649 branch 2162292867793093651, undo_log deleted with GlobalFinished
2024-09-15T21:58:20.344+08:00  INFO 4560 --- [storage-service] [_RMROLE_1_14_16] i.seata.rm.datasource.DataSourceManager  : branch rollback success, xid:192.168.145.128:8091:2162292867793093649, branchId:2162292867793093651
2024-09-15T21:58:20.344+08:00  INFO 4560 --- [storage-service] [_RMROLE_1_14_16] io.seata.rm.AbstractRMHandler            : Branch Rollbacked result: PhaseTwo_Rollbacked

2024-09-15T21:58:20.210+08:00  INFO 11676 --- [order-service] [io-18083-exec-7] o.e.order.controller.OrderController     : Order Service Begin ... xid: 192.168.145.128:8091:2162292867793093649
2024-09-15T21:58:20.221+08:00  INFO 11676 --- [order-service] [io-18083-exec-7] io.seata.rm.AbstractResourceManager      : branch register success, xid:192.168.145.128:8091:2162292867793093649, branchId:2162292867793093653, lockKeys:order_tbl:2
2024-09-15T21:58:20.330+08:00 ERROR 11676 --- [order-service] [io-18083-exec-7] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: feign.FeignException$InternalServerError: [500] during [POST] to [http://account-service/account/debit?userId=U100001&money=400] [AccountService#debit(String,int)]: [{"timestamp":"2024-09-15T13:58:20.329+00:00","status":500,"error":"Internal Server Error","path":"/account/debit"}]] with root cause
feign.FeignException$InternalServerError: [500] during [POST] to [http://account-service/account/debit?userId=U100001&money=400] [AccountService#debit(String,int)]: [{"timestamp":"2024-09-15T13:58:20.329+00:00","status":500,"error":"Internal Server Error","path":"/account/debit"}]
2024-09-15T21:58:20.348+08:00  INFO 11676 --- [order-service] [_RMROLE_1_14_16] i.s.c.r.p.c.RmBranchRollbackProcessor    : rm handle branch rollback process:BranchRollbackRequest{xid='192.168.145.128:8091:2162292867793093649', branchId=2162292867793093653, branchType=AT, resourceId='jdbc:mysql://192.168.145.128:3306/seata', applicationData='null'}
2024-09-15T21:58:20.349+08:00  INFO 11676 --- [order-service] [_RMROLE_1_14_16] io.seata.rm.AbstractRMHandler            : Branch Rollbacking: 192.168.145.128:8091:2162292867793093649 2162292867793093653 jdbc:mysql://192.168.145.128:3306/seata
2024-09-15T21:58:20.376+08:00  INFO 11676 --- [order-service] [_RMROLE_1_14_16] i.s.r.d.undo.AbstractUndoLogManager      : xid 192.168.145.128:8091:2162292867793093649 branch 2162292867793093653, undo_log deleted with GlobalFinished
2024-09-15T21:58:20.377+08:00  INFO 11676 --- [order-service] [_RMROLE_1_14_16] i.seata.rm.datasource.DataSourceManager  : branch rollback success, xid:192.168.145.128:8091:2162292867793093649, branchId:2162292867793093653
2024-09-15T21:58:20.377+08:00  INFO 11676 --- [order-service] [_RMROLE_1_14_16] io.seata.rm.AbstractRMHandler            : Branch Rollbacked result: PhaseTwo_Rollbacked

2024-09-15T21:58:20.328+08:00  INFO 12564 --- [account-service] [io-18084-exec-3] o.e.a.controller.AccountController       : Account Service ... xid: 192.168.145.128:8091:2162292867793093649
2024-09-15T21:58:20.328+08:00 ERROR 12564 --- [account-service] [io-18084-exec-3] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: java.lang.RuntimeException: seata fail test] with root cause
java.lang.RuntimeException: seata fail test
	at org.example.account.controller.AccountController.debit(AccountController.java:29) ~[classes/:na]

从日志中可以看出，仓储服务和订单服务已经执行，发生异常后进行了回退的动作，并且在这个过程中之前创建的undo_log表，也就是AT需要借助数据库完成分布式事务的功能

3.4 控制台

从控制台也能看到我们的事务执行信息，但是这个过程很短，事务执行完成几秒后可能就删除了

在这里插入图片描述

总结

回到顶部

分布式事务到这里就要告一段落了，希望大家都能学到东西吧，这部分的源码已经上传附件，over！

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