spring cloud alibaba + tx-lcn 实现微服务的分布式事务管理

清疚 2023-06-25 02:10 7阅读 0赞

**Spring Cloud Alibaba官方文档：[https://github.com/alibaba/spring-cloud-alibaba/blob/master/README-zh.md][https_github.com_alibaba_spring-cloud-alibaba_blob_master_README-zh.md]**

**Spring Cloud Alibaba源码：[https://github.com/alibaba/spring-cloud-alibaba][https_github.com_alibaba_spring-cloud-alibaba]**

**Tx-Lcn官方文档：[http://www.txlcn.org/zh-cn/docs/start.html][http_www.txlcn.org_zh-cn_docs_start.html]**

**Tx-Lcn源码：[https://github.com/codingapi/tx-lcn][https_github.com_codingapi_tx-lcn]**

**Tx-Lcn官方demo代码：[https://github.com/codingapi/txlcn-demo][https_github.com_codingapi_txlcn-demo]**

**强烈建议先看官方文档，下面的代码都是建立在对 spring cloud alibaba 和 tx-lcn 有一些简单了解的基础上写的，对于一些名词这里不做解释。**

**首先到**[https://github.com/alibaba/nacos/releases][https_github.com_alibaba_nacos_releases]下载**nacos-server，双击start.cmd启动nacos，默认端口8848，用户名nacos，密码nacos。**

**建库：txlcn-demo**

**建表语句：**

CREATE TABLE `t_demo` (
      `id` bigint(20) NOT NULL AUTO_INCREMENT,
      `kid` varchar(45) DEFAULT NULL,
      `group_id` varchar(64) DEFAULT NULL,
      `demo_field` varchar(255) DEFAULT NULL,
      `app_name` varchar(128) DEFAULT NULL,
      `create_time` datetime DEFAULT NULL,
      PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=16 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC;

**创建全局依赖管理：**

**项目结构**

![20191224135706663.png][]

**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>
    
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.6.RELEASE</version>
            <relativePath/> 
        </parent>
    
        <groupId>com.qdz</groupId>
        <artifactId>txlcn-study</artifactId>
        <version>1.0.0</version>
    
        <properties>
            <spring-cloud.version>Greenwich.SR2</spring-cloud.version>
            <spring-cloud-alibaba.version>0.9.0.RELEASE</spring-cloud-alibaba.version>
        </properties>
    
        <dependencyManagement>
            <dependencies>
                <dependency>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-dependencies</artifactId>
                    <version>${spring-cloud.version}</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
                <dependency>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                    <version>${spring-cloud-alibaba.version}</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
            </dependencies>
        </dependencyManagement>
    
        <dependencies>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
            </dependency>
    
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>1.3.2</version>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${spring-cloud-alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-openfeign</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
                <version>2.1.2.RELEASE</version>
            </dependency>
    
        </dependencies>
    </project>

**创建tx-manager**

**项目结构：**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjM2MjU0NA_size_16_color_FFFFFF_t_70][]

**pom.xml**

**application.properties**

spring.application.name=tx-manager
    spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848
    
    server.port=7970
    management.endpoints.web.exposure.include="*"
    
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver
    spring.datasource.url=jdbc:mysql://127.0.0.1:3306/tx-manager?characterEncoding=UTF-8&serverTimezone=GMT%2B8
    spring.datasource.username=root
    spring.datasource.password=root
    
    mybatis.configuration.map-underscore-to-camel-case=true
    mybatis.configuration.use-generated-keys=true
    spring.jpa.database-platform=org.hibernate.dialect.MySQLDialect
    
    #tx-lcn.logger.enabled=true
    # TxManager Host Ip
    #tx-lcn.manager.host=127.0.0.1
    # TxClient连接请求端口
    #tx-lcn.manager.port=8070
    # 心跳检测时间(ms)
    #tx-lcn.manager.heart-time=15000
    # 分布式事务执行总时间
    #tx-lcn.manager.dtx-time=30000
    #参数延迟删除时间单位ms
    #tx-lcn.message.netty.attr-delay-time=10000
    #tx-lcn.manager.concurrent-level=128
    # 开启日志
    #tx-lcn.logger.enabled=true
    #logging.level.com.codingapi=debug
    #redis 主机
    #spring.redis.host=127.0.0.1
    #redis 端口
    #spring.redis.port=6379
    #redis 密码
    #spring.redis.password=

**启动类：**

@SpringBootApplication
    @EnableTransactionManagerServer
    @EnableDiscoveryClient
    public class TransactionManagerApplication {
        public static void main(String[] args) {
            SpringApplication.run(TransactionManagerApplication.class, args);
        }
    }

至此，tx-manager配置完毕。可访问：[http://127.0.0.1:7970/][http_127.0.0.1_7970]查看tx-manager情况，默认密码 codingapi

**服务a：**

**服务a的项目结构**

![2019122413232249.png][]

**pom.xml**

**application.yml**

spring:
      application:
        name: tx-client-a
      cloud:
        nacos:
          discovery:
            server-addr: 127.0.0.1:8848
      datasource:
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/txlcn-demo?characterEncoding=UTF-8&serverTimezone=UTC
        username: root
        password: root
        hikari:
          maximum-pool-size: 20
    
    server:
      port: 8667
    
    mybatis:
      configuration:
        map-underscore-to-camel-case: true
        use-generated-keys: true
    
    management:
      endpoints:
        web:
          exposure:
            include: "*"
    
    # 开启启动LCN负载均衡策略
    tx-lcn:
      ribbon:
        loadbalancer:
          dtx:
            enabled: true
    #  # tm的本机默认端口
    #  client:
    #    manager-address: 127.0.0.1:8667

**启动类：**

@SpringBootApplication
    @EnableDistributedTransaction
    @EnableFeignClients
    @EnableDiscoveryClient
    public class ClientAApplication {
        public static void main(String[] args) {
            SpringApplication.run(ClientAApplication.class, args);
        }
    }

**AController：**

@RestController
    public class AController {
    
        @Autowired
        private AService aService;
    
        /**
         * 测试分布式事务
         * @return
         */
        @PostMapping("/client/a/save")
        public Demo save() {
            Demo demo = new Demo();
            demo.setKid("a");
            demo.setAppName("tx-client-a");
            demo.setGroupId("a");
            aService.save(demo);
            return demo;
        }
    }

**Demo：**

@AllArgsConstructor
    @NoArgsConstructor
    @Data
    public class Demo {
        private Long id;
        private String kid = RandomUtils.randomKey();
        private String demoField;
        private String groupId;
        private Date createTime;
        private String appName;
    
    }

**BFeign：**

@FeignClient(value = "tx-client-b")
    public interface BFeign {
    
        @PostMapping("/client/b/save")
        void save();
    }

**AMapper：**

@Mapper
    public interface AMapper  {
    
        @Insert("insert into t_demo(kid, demo_field, group_id, create_time,app_name) values(#{kid}, #{demoField}, #{groupId}, #{createTime},#{appName})")
        void save(Demo demo);
    }

**AService：**

@Service
    public class AService {
    
        @Autowired
        private AMapper aMapper;
    
        @Autowired
        private BFeign bFeign;
    
        @Transactional
        @LcnTransaction
        public void save(Demo entity) {
            // 调用本地事务
            aMapper.save(entity);
    //        int i = 1/0; // 这里抛出异常属于本地事务需要加@Transactional注解
    
            // 调用分布式事务，调用B服务的BService.save()方法
            // 此方法若抛出异常，使用@LcnTransaction注解就可以使上面数据回滚
            bFeign.save();
        }
    }

至此，A服务代码完毕

**B服务**

**项目结构：**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjM2MjU0NA_size_16_color_FFFFFF_t_70 1][]

**pom.xml**

**application.yml**

spring:
      application:
        name: tx-client-b
      cloud:
        nacos:
          discovery:
            server-addr: 127.0.0.1:8848
      datasource:
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/txlcn-demo?characterEncoding=UTF-8&serverTimezone=UTC
        username: root
        password: root
        hikari:
          maximum-pool-size: 20
    
    server:
      port: 8668
    
    mybatis:
      configuration:
        map-underscore-to-camel-case: true
        use-generated-keys: true
    
    management:
      endpoints:
        web:
          exposure:
            include: "*"
    
    # 开启启动LCN负载均衡策略
    tx-lcn:
      ribbon:
        loadbalancer:
          dtx:
            enabled: true
    #  # tm的本机默认端口
    #  client:
    #    manager-address: 127.0.0.1:8668

**启动类：**

@SpringBootApplication
    @EnableDistributedTransaction
    @EnableDiscoveryClient
    public class ClientBApplication {
        public static void main(String[] args) {
            SpringApplication.run(ClientBApplication.class, args);
        }
    }

**BController：**

@RestController
    public class BController {
    
        @Autowired
        private BService bService;
    
        @PostMapping("/client/b/save")
        public void save() {
            Demo demo = new Demo();
            demo.setKid("b");
            demo.setAppName("tx-client-b");
            demo.setGroupId("b");
            demo.setDemoField("b");
            bService.save(demo);
        }
    }

**Demo：**和A服务是一样的。

**BMapper：**

@Mapper
    public interface BMapper {
    
        @Insert("insert into t_demo(kid, demo_field, group_id, create_time,app_name) values(#{kid}, #{demoField}, #{groupId}, #{createTime},#{appName})")
        void save(Demo demo);
    }

**BService：**

@Service
    public class BService {
    
        @Autowired
        private BMapper bMapper;
    
        public void save(Demo demo) {
            // 这里抛出异常，可以发现a服务数据不会入库
            // int i = 1/0;
            bMapper.save(demo);
        }
    }

至此：B服务代码完毕。

由上可见，A服务的save方法会保存a服务的demo数据到数据库，并且还会调用B服务的save方法保存数据。

先启动tx-manager-study项目，然后启动clientA和ClientB，开始访问：

**情况一：**

发送[http://localhost:8667//client/a/save][http_localhost_8667_client_a_save] Post请求，在没有异常抛出的时候可以看见有两条数据入库，分别是A服务和B服务的

![20191224134355301.png][]

**情况二：**

在AServcie的save方法中把 int i = 1/0 放开，让其在运行时抛出异常，此时发送请求，可以看到，A，B服务的数据都不会插入成功，这是@Transactional本地事务在起作用。

**情况三：**

AService的save方法中的 int i = 1/0 注释掉，将BService的sava方法中的int i = 1/0 放开，发送请求，A，B服务数据依然不会插入成功，此时即为分布式事务@LcnTransaction注解在起作用。

**总结：**

tx-lcn用法比较简单

1. 配置一个manager：导依赖，做配置，写一个启动类，注意加上@EnableTransactionManagerServer注解表示是分布式事务管理方。

2.将需要进行分布式事务管理的服务作为tx-lcn的客户端：导依赖，做配置，启动类上加上@EnableDistributedTransaction注解表示开启分布式事务，最后在方法上加上@LcnTransaction注解即可。同时不要忘了加@Transactional注解。

[https_github.com_alibaba_spring-cloud-alibaba_blob_master_README-zh.md]: https://github.com/alibaba/spring-cloud-alibaba/blob/master/README-zh.md
[https_github.com_alibaba_spring-cloud-alibaba]: https://github.com/alibaba/spring-cloud-alibaba
[http_www.txlcn.org_zh-cn_docs_start.html]: http://www.txlcn.org/zh-cn/docs/start.html
[https_github.com_codingapi_tx-lcn]: https://github.com/codingapi/tx-lcn
[https_github.com_codingapi_txlcn-demo]: https://github.com/codingapi/txlcn-demo
[https_github.com_alibaba_nacos_releases]: https://github.com/alibaba/nacos/releases
[20191224135706663.png]: https://img-blog.csdnimg.cn/20191224135706663.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjM2MjU0NA_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20191224140621240.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjM2MjU0NA==,size_16,color_FFFFFF,t_70
[http_127.0.0.1_7970]: http://127.0.0.1:7970/
[2019122413232249.png]: https://img-blog.csdnimg.cn/2019122413232249.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjM2MjU0NA_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20191224133715382.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjM2MjU0NA==,size_16,color_FFFFFF,t_70
[http_localhost_8667_client_a_save]: http://localhost:8667//client/a/save
[20191224134355301.png]: https://img-blog.csdnimg.cn/20191224134355301.png