上一篇讲了Seata-Server服务端的搭建和配置，我们使用nacos管理seata-server服务和配置文件。这一篇我们业务微服务和seata-server打通，实现全局事务。
有一点需要注意，seata-server我们用的是1.4.0版本，客户端我们也要用1.4.0版本，版本对应问题少，
以前的版本 总会出现各种问题，比如：
no available service 'null' found, please make sure registry config correct
no available service 'default' found, please make sure registry config correct
1.4.0版本修改了不少bug，按着官网要求，一般都会成功。

1. 依赖引入

微服务父工程是这样管理spring-cloud-alibaba依赖的：

<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <!-- 父工程 -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.11.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <groupId>com.test</groupId>
    <artifactId>test</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <name>test</name>
    <description>test</description>
    <packaging>pom</packaging>

    <properties>
        <!-- Enviroment setting -->
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>

        <!-- Spring Cloud Settings -->
        <spring-cloud-alibaba.version>2.2.1.RELEASE</spring-cloud-alibaba.version>
        <spring-cloud.version>Hoxton.SR9</spring-cloud.version>

        <!-- Spring Boot Settings -->
        <spring-boot-alibaba-druid.version>1.1.22</spring-boot-alibaba-druid.version>
        <mybatis-plus.version>3.4.1</mybatis-plus.version>

        <!-- Commons Settings -->
        <swagger.version>2.9.2</swagger.version>
        <swagger-annotations.version>1.5.21</swagger-annotations.version>
        <hutool.version>5.5.2</hutool.version>
        <poi.version>4.1.2</poi.version>
        <websocket.version>1.5.1</websocket.version>
    </properties>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <dependency>
                <groupId>com.alibaba.cloud</groupId>
                <artifactId>spring-cloud-alibaba-dependencies</artifactId>
                <version>${spring-cloud-alibaba.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <!-- Spring Boot Begin -->
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid-spring-boot-starter</artifactId>
                <version>${spring-boot-alibaba-druid.version}</version>
            </dependency>
            <dependency><!-- mybatis-plus -->
                <groupId>com.baomidou</groupId>
                <artifactId>mybatis-plus-boot-starter</artifactId>
                <version>${mybatis-plus.version}</version>
            </dependency>

            <!-- Commons Settings -->
            <dependency>
                <groupId>cn.hutool</groupId>
                <artifactId>hutool-all</artifactId>
                <version>${hutool.version}</version>
            </dependency>
            <dependency>
            <groupId>org.apache.poi</groupId>
                <artifactId>poi-ooxml</artifactId>
                <version>${poi.version}</version>
            </dependency>
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi</artifactId>
                <version>${poi.version}</version>
            </dependency>
            <dependency>
                <groupId>org.java-websocket</groupId>
                <artifactId>Java-WebSocket</artifactId>
                <version>${websocket.version}</version>
            </dependency>
            
            <!--引入swagger -->
            <!-- 排除springfox-swagger2 引入的swagger-annotations、swagger-models 1.5.20版本，手动引入1.5.21版本的jar, 
                在使用@ApiModelProperty注解在字段上时，如果字段的类型为Long或是int类型， 那么程序启动后，访问swagger-ui.html的页面，程序会报错: 
                java.lang.NumberFormatException: For input string: "" -->
            <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger2</artifactId>
                <version>${swagger.version}</version>
                <exclusions>
                    <exclusion>
                        <groupId>io.swagger</groupId>
                        <artifactId>swagger-annotations</artifactId>
                    </exclusion>
                    <exclusion>
                        <groupId>io.swagger</groupId>
                        <artifactId>swagger-models</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger-ui</artifactId>
                <version>${swagger.version}</version>
            </dependency>
            <dependency>
                <groupId>io.swagger</groupId>
                <artifactId>swagger-annotations</artifactId>
                <version>${swagger-annotations.version}</version>
            </dependency>
            <dependency>
                <groupId>io.swagger</groupId>
                <artifactId>swagger-models</artifactId>
                <version>${swagger-annotations.version}</version>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <plugins>
            <!-- install -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-install-plugin</artifactId>
            </plugin>

            <!-- clean -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-clean-plugin</artifactId>
            </plugin>
    </plugins>
    </build>

    <repositories>
        <repository>
            <id>aliyun-repos</id>
            <name>Aliyun Repository</name>
            <url>http://maven.aliyun.com/nexus/content/groups/public</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
</project>

因spring-cloud-alibaba的管理版本是2.2.1版本，自带的seata客户端是1.1.0，版本不对，参考官方推荐格式，各个微服务引入seata：

<!-- seata -->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    <exclusions>
        <exclusion>
            <groupId>io.seata</groupId>
            <artifactId>seata-spring-boot-starter</artifactId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>io.seata</groupId>
    <artifactId>seata-spring-boot-starter</artifactId>
    <version>1.4.2</version><!--$NO-MVN-MAN-VER$-->
</dependency>

2. 修改application.yml

修改微服务配置文件，添加seata相关配置
配置信息在GitHub资源中client文件夹中
seata-application.yml
需要修改的主要是nacos的注册和配置，还有其他标有注释的（因是全局统一事务，所以各个微服务应由seata做统一代理），上一节服务端配置包含了客户端配置，可以用nacos中已有的配置，所以这里可以精简

seata:
  enabled: true
  #注册到seata-server用到的名字
  application-id: test123 
  # 这个和seata-server的配置中保持一致，这使用的默认值
  tx-service-group: my_test_tx_group 
  # 开启seata-server做数据代理
  enable-auto-data-source-proxy: true
  data-source-proxy-mode: AT
  # 这个jdk代理不打开报错
  use-jdk-proxy: true
  config: 
    # 修改nacos信息
    type: nacos
    nacos:
      namespace: ""
      server-addr: 192.168.1.10:8848
      group: SEATA_GROUP
      dataId: "seataServer.properties" # 1.4.2新加的属性，配置都在这个里面
      username: "nacos"
      password: "nacos"
  registry: 
    # 修改nacos信息
    type: nacos
    load-balance: RandomLoadBalance
    load-balance-virtual-nodes: 10
    nacos: 
      # 这个和registry.conf中保持一致
      application: seata-server
      server-addr: 192.168.1.10:8848
      group : DEFAULT_GROUP
      username: "nacos"
      password: "nacos"

3. 修改项目

• 1. 启动入口排除DataSourceAutoConfiguration.class

  @SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
  @EnableDiscoveryClient
  @MapperScan({"com.test.service.**.dao"})
  @EnableFeignClients
  public class TestApplication {
  
      public static void main(String[] args) {
          SpringApplication.run(TestApplication.class, args);
      }
  }
  

• 2. 我用了mybatis-plus，在mybatis-plus的配置中开启了事务管理，具体有没有用还不清楚

  @Configuration
  @EnableTransactionManagement
  public class MybatisPlusConfig {
    
      /**
         * 新的分页插件,一缓和二缓遵循mybatis的规则,
         * 需要设置 MybatisConfiguration#useDeprecatedExecutor = false 避免缓存出现问题(该属性会在旧插件移除后一同移除)
       */
      @Bean
      public MybatisPlusInterceptor mybatisPlusInterceptor() {
          MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
          interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
          return interceptor;
      }
  
      @SuppressWarnings("deprecation")
      @Bean
      public ConfigurationCustomizer configurationCustomizer() {
          return configuration -> configuration.setUseDeprecatedExecutor(false);
      }
  }
  

• 3. 修改注解
     将原来服务中的@Transactional改为@GlobalTransactional

4. 添加undo_log表

AT模式需要用到，在GitHub资源文件夹的client目录下，服务提供者和消费者对应的库中都要添加
undo_log-mysql.sql

5. 服务启动

服务启动后，过一会儿能看到RM和TM角色注册成功的信息，同时带有版本号，请注意和服务端一致（1.4.0）；seata-server端也有注册成功信息显示。