Deployment and integration of seata

1, Deploying the TC server of Seata

1. Download

First, we need to download the Seata Server package at http😕/seata.io/zh-cn/blog/download.html

Of course, the pre class materials are also ready:

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2. Decompression

Unzip the zip package in a non Chinese directory. Its directory structure is as follows:

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3. Modify configuration

Modify the registry.conf file in the conf Directory:

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The contents are as follows:

registry {
  # For the registry class of tc service, select nacos here, or eureka, zookeeper, etc
  type = "nacos"

  nacos {
    # seata tc service is registered with the service name of nacos, which can be customized
    application = "seata-tc-server"
    serverAddr = "127.0.0.1:8848"
    group = "DEFAULT_GROUP"
    namespace = ""
    cluster = "SH"
    username = "nacos"
    password = "nacos"
  }
}

config {
  # The way to read the configuration file of the tc server is to read it from the nacos configuration center, so that if the tc is a cluster, the configuration can be shared
  type = "nacos"
  # Configure nacos address and other information
  nacos {
    serverAddr = "127.0.0.1:8848"
    namespace = ""
    group = "SEATA_GROUP"
    username = "nacos"
    password = "nacos"
    dataId = "seataServer.properties"
  }
}

4. Add configuration in nacos

In particular, in order to enable the cluster of tc services to share configuration, we chose nacos as the unified configuration center. Therefore, the server configuration file seataServer.properties needs to be configured in nacos.

The format is as follows:

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The configuration contents are as follows:

# Data storage mode, db represents database
store.mode=db
store.db.datasource=druid
store.db.dbType=mysql
store.db.driverClassName=com.mysql.jdbc.Driver
store.db.url=jdbc:mysql://127.0.0.1:3306/seata?useUnicode=true&rewriteBatchedStatements=true
store.db.user=root
store.db.password=123
store.db.minConn=5
store.db.maxConn=30
store.db.globalTable=global_table
store.db.branchTable=branch_table
store.db.queryLimit=100
store.db.lockTable=lock_table
store.db.maxWait=5000
# Transaction and log configuration
server.recovery.committingRetryPeriod=1000
server.recovery.asynCommittingRetryPeriod=1000
server.recovery.rollbackingRetryPeriod=1000
server.recovery.timeoutRetryPeriod=1000
server.maxCommitRetryTimeout=-1
server.maxRollbackRetryTimeout=-1
server.rollbackRetryTimeoutUnlockEnable=false
server.undo.logSaveDays=7
server.undo.logDeletePeriod=86400000

# Transmission mode between client and server
transport.serialization=seata
transport.compressor=none
# Turn off the metrics function to improve performance
metrics.enabled=false
metrics.registryType=compact
metrics.exporterList=prometheus
metrics.exporterPrometheusPort=9898

The database address, user name and password need to be modified into your own database information.

5. Create database tables

Special note: when managing distributed transactions, the tc service needs to record transaction related data into the database. You need to create these tables in advance.

Create a new database named seata and run the sql file provided in the pre class materials:

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These tables mainly record global transactions, branch transactions and global lock information:

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Branch transaction table
-- ----------------------------
DROP TABLE IF EXISTS `branch_table`;
CREATE TABLE `branch_table`  (
  `branch_id` bigint(20) NOT NULL,
  `xid` varchar(128) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `transaction_id` bigint(20) NULL DEFAULT NULL,
  `resource_group_id` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `resource_id` varchar(256) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `branch_type` varchar(8) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `status` tinyint(4) NULL DEFAULT NULL,
  `client_id` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `application_data` varchar(2000) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `gmt_create` datetime(6) NULL DEFAULT NULL,
  `gmt_modified` datetime(6) NULL DEFAULT NULL,
  PRIMARY KEY (`branch_id`) USING BTREE,
  INDEX `idx_xid`(`xid`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Global transaction table
-- ----------------------------
DROP TABLE IF EXISTS `global_table`;
CREATE TABLE `global_table`  (
  `xid` varchar(128) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `transaction_id` bigint(20) NULL DEFAULT NULL,
  `status` tinyint(4) NOT NULL,
  `application_id` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `transaction_service_group` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `transaction_name` varchar(128) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `timeout` int(11) NULL DEFAULT NULL,
  `begin_time` bigint(20) NULL DEFAULT NULL,
  `application_data` varchar(2000) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  `gmt_create` datetime NULL DEFAULT NULL,
  `gmt_modified` datetime NULL DEFAULT NULL,
  PRIMARY KEY (`xid`) USING BTREE,
  INDEX `idx_gmt_modified_status`(`gmt_modified`, `status`) USING BTREE,
  INDEX `idx_transaction_id`(`transaction_id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;

SET FOREIGN_KEY_CHECKS = 1;

6. Start TC service

Enter the bin directory and run seata-server.bat:

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After successful startup, Seata server should have registered with the nacos registry.

Open a browser to access the nacos address: http://localhost:8848 , then enter the service list page, and you can see the information of Seata TC server:

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2, Microservice integration seata

1. Introduce dependency

First, we need to introduce seata dependency into microservices:

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    <exclusions>
        <!--Lower version, 1.3.0，Therefore exclude-->
        <exclusion>
            <artifactId>seata-spring-boot-starter</artifactId>
            <groupId>io.seata</groupId>
        </exclusion>
    </exclusions>
</dependency>
<!--seata starter Adopt 1.4.2 edition-->
<dependency>
    <groupId>io.seata</groupId>
    <artifactId>seata-spring-boot-starter</artifactId>
    <version>${seata.version}</version>
</dependency>

2. Modify the configuration file

You need to modify the application.yml file and add some configurations:

seata:
  registry: # The configuration of the TC service registry. The microservice obtains the TC service address from the registry according to this information
    # Refer to the configuration in the registry.conf of the tc service
    type: nacos
    nacos: # tc
      server-addr: 127.0.0.1:8848
      namespace: ""
      group: DEFAULT_GROUP
      application: seata-tc-server # Service name of tc service in nacos
      cluster: SH
  tx-service-group: seata-demo # Transaction group, which is used to obtain the cluster name of tc service
  service:
    vgroup-mapping: # Mapping relationship between transaction group and TC service cluster
      seata-demo: SH

3, High availability of TC services and remote disaster recovery

1. TC cluster simulating remote disaster recovery

It is planned to start tc service nodes of two seata s:

Node name	ip address	Port number	Cluster name
seata	127.0.0.1	8091	SH
seata2	127.0.0.1	8092	HZ

We have started a seata service before. The port is 8091 and the cluster name is SH.

Now, make a copy of the Seata directory and name it seata2

Modify seata2/conf/registry.conf as follows:

registry {
  # For the registry class of tc service, select nacos here, or eureka, zookeeper, etc
  type = "nacos"

  nacos {
    # seata tc service is registered with the service name of nacos, which can be customized
    application = "seata-tc-server"
    serverAddr = "127.0.0.1:8848"
    group = "DEFAULT_GROUP"
    namespace = ""
    cluster = "HZ"
    username = "nacos"
    password = "nacos"
  }
}

config {
  # The way to read the configuration file of the tc server is to read it from the nacos configuration center, so that if the tc is a cluster, the configuration can be shared
  type = "nacos"
  # Configure nacos address and other information
  nacos {
    serverAddr = "127.0.0.1:8848"
    namespace = ""
    group = "SEATA_GROUP"
    username = "nacos"
    password = "nacos"
    dataId = "seataServer.properties"
  }
}

Enter the seata2/bin directory and run the command:

seata-server.bat -p 8092

Open the nacos console to view the list of services:

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Click in details to view:

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2. Configure the transaction group mapping to nacos

Next, we need to configure the mapping relationship between TX service group and cluster to the nacos configuration center.

Create a new configuration:

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The configuration is as follows:

# Transaction group mapping relationship
service.vgroupMapping.seata-demo=SH

service.enableDegrade=false
service.disableGlobalTransaction=false
# Communication configuration with TC service
transport.type=TCP
transport.server=NIO
transport.heartbeat=true
transport.enableClientBatchSendRequest=false
transport.threadFactory.bossThreadPrefix=NettyBoss
transport.threadFactory.workerThreadPrefix=NettyServerNIOWorker
transport.threadFactory.serverExecutorThreadPrefix=NettyServerBizHandler
transport.threadFactory.shareBossWorker=false
transport.threadFactory.clientSelectorThreadPrefix=NettyClientSelector
transport.threadFactory.clientSelectorThreadSize=1
transport.threadFactory.clientWorkerThreadPrefix=NettyClientWorkerThread
transport.threadFactory.bossThreadSize=1
transport.threadFactory.workerThreadSize=default
transport.shutdown.wait=3
# RM configuration
client.rm.asyncCommitBufferLimit=10000
client.rm.lock.retryInterval=10
client.rm.lock.retryTimes=30
client.rm.lock.retryPolicyBranchRollbackOnConflict=true
client.rm.reportRetryCount=5
client.rm.tableMetaCheckEnable=false
client.rm.tableMetaCheckerInterval=60000
client.rm.sqlParserType=druid
client.rm.reportSuccessEnable=false
client.rm.sagaBranchRegisterEnable=false
# TM configuration
client.tm.commitRetryCount=5
client.tm.rollbackRetryCount=5
client.tm.defaultGlobalTransactionTimeout=60000
client.tm.degradeCheck=false
client.tm.degradeCheckAllowTimes=10
client.tm.degradeCheckPeriod=2000

# undo log configuration
client.undo.dataValidation=true
client.undo.logSerialization=jackson
client.undo.onlyCareUpdateColumns=true
client.undo.logTable=undo_log
client.undo.compress.enable=true
client.undo.compress.type=zip
client.undo.compress.threshold=64k
client.log.exceptionRate=100

3. The micro service reads the nacos configuration

Next, you need to modify the application.yml file of each microservice to let the microservice read the client.properties file in nacos:

seata:
  config:
    type: nacos
    nacos:
      server-addr: 127.0.0.1:8848
      username: nacos
      password: nacos
      group: SEATA_GROUP
      data-id: client.properties

Restart the microservice. Whether the microservice is connected to the SH cluster of tc or the HZ cluster of tc is determined by the client.properties of nacos.

lient.log.exceptionRate=100

## 3. The micro service reads the nacos configuration

Next, you need to modify the of each microservice application.yml File for microservice to read nacos Medium client.properties File:

```yaml
seata:
  config:
    type: nacos
    nacos:
      server-addr: 127.0.0.1:8848
      username: nacos
      password: nacos
      group: SEATA_GROUP
      data-id: client.properties

Restart the microservice. Whether the microservice is connected to the SH cluster of tc or the HZ cluster of tc is determined by the client.properties of nacos.