四 Spring-cloud-seata-demo

Introduction

Based on Seata distributed transaction Demo
Bank A and Bank B services transfer
source code address: https://gitee.com/xrzi2016/spring-cloud-seata-demo

Instructions for use

1. Start seata-server: sh ./bin/seata-server.sh
   

2. Install seata-common to the local factory library: mvn install
   

3. Start the registration center: mvn spring-boot: run
   

4. 启动bank-a： mvn spring-boot:run
   

See seata-serve output

5. 启动bank-b： mvn spring-boot:run
   

See seata-serve output

Instructions for use

1. Normal test: http://127.0.0.1:8081/bank-a/updAmount

   100 yuan for Zhang San account in bank-a library
   

   Bank-b Li Si account deducts 100 yuan

2. Abnormal test: http://127.0.0.1:8081/bank-a/updAmount?mode=OUT

   The amount in bank-a bank and bank-b bank remains unchanged
   

   See seata-serve output rollback information

Spring Cloud quickly integrates Seata

Official address: http://seata.io/zh-cn/

官方Github：https://github.com/seata/seata-samples/blob/master/doc/quick-integration-with-spring-cloud.md#registryconf

1. Add dependencies

Maven

<dependency>
	<groupId>com.alibaba.cloud</groupId>
	<artifactId>spring-cloud-starter-alibaba-seata</artifactId>
        <version>2.1.0.RELEASE</version>
</dependency>

It should be noted that the GroupId of the graduated version of Spring Cloud Alibaba is com.alibaba.cloud

spring-cloud-starter-alibaba-seata depends only on spring-cloud-alibaba-seata, so adding spring-cloud-starter-alibaba-seata and spring-cloud-alibaba-seata in the project is the same

2. Add Seata configuration file

registry.conf
This configuration is used to specify the TC's registry and configuration file. The default is file; if another registry is used, Seata-Server is also required to register to the configuration center

registry.conf

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "file"

  nacos {
    serverAddr = "localhost"
    namespace = "public"
    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 = "public"
    cluster = "default"
  }
  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"
  }
}

file.conf
This configuration is used to specify the relevant attributes of TC; if you use the registration center, you can also add the configuration to the configuration center

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->rgroup
  vgroup_mapping.my_test_tx_group = "default"
  #only support single node
  default.grouplist = "127.0.0.1:8091"
  #degrade current not support
  enableDegrade = false
  #disable
  disable = false
  #unit ms,s,m,h,d represents milliseconds, seconds, minutes, hours, days, default permanent
  max.commit.retry.timeout = "-1"
  max.rollback.retry.timeout = "-1"
}

client {
  async.commit.buffer.limit = 10000
  lock {
    retry.internal = 10
    retry.times = 30
  }
  report.retry.count = 5
}

## transaction log store
store {
  ## store mode: file、db
  mode = "file"

  ## 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"
    url = "jdbc:mysql://127.0.0.1:3306/seata"
    user = "mysql"
    password = "mysql"
    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 {
  committing-retry-delay = 30
  asyn-committing-retry-delay = 30
  rollbacking-retry-delay = 30
  timeout-retry-delay = 30
}

transaction {
  undo.data.validation = true
  undo.log.serialization = "jackson"
}

## metrics settings
metrics {
  enabled = false
  registry-type = "compact"
  # multi exporters use comma divided
  exporter-list = "prometheus"
  exporter-prometheus-port = 9898
}

It should be noted that the configuration of service.vgroup_mapping is $ {spring.application.name} -fescar-service-group by default in Spring Cloud. You can specify spring.cloud.alibaba.seata.tx-service- by application.properties The group attribute is covered, but it must be consistent with the file.conf, otherwise it will prompt no available server to connect

3. Inject data source

Seata implements branch transactions by proxying data sources; both MyBatis and JPA need to be injected into io.seata.rm.datasource.DataSourceProxy. The difference is that MyBatis also needs to inject additional org.apache.ibatis.session.SqlSessionFactory

MyBatis

@Configuration
public class DataSourceProxyConfig {

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource dataSource() {
        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);
        return sqlSessionFactoryBean.getObject();
    }
}

4. Add the undo_log table

Add the undo_log table in the business-related database to save the data that needs to be rolled back

CREATE 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

5. Start Seata-Server

Download the corresponding version of Seata-Server at https://github.com/seata/seata/releases, modify registry.conf to the corresponding configuration (if you use file, you do not need to modify it), unzip and start with the following command:

sh ./bin/seata-server.sh

6. Use @GlobalTransactional to start the transaction

Use @GlobalTransactional on the method of the business initiator to start the global transaction. Seata will add the xid of the transaction to the request to call other services through the interceptor to implement distributed transactions