Ali seata Getting distributed transaction (Pit)

1. Ali distributed seata entry Affairs (Pit)

1.1 Introduction

• seataIs feascarrenamed from, this is Ali out of the open source distributed transaction in early 2007 framework, originally wanted to study just came out next, was delayed until now, currently 0.8.0version, see the version you know this is a relatively new project, but now there are tens of thousands of the Star, shows the influence of Ali. But while Ali has endorsed the digging had to dig, it declared that it is relatively simple integration, is now due to its advantages of incomplete documentation, several title of the document did not point into content, do not know why deleted, it may be updated faster, keep up the rhythm simply delete the document [manual funny]

1.2. Quick Start

1.2.1. 找 Demo

• In general, we want to integrate third-party middleware is certainly going to find that the official demo, the official document below, I found Seata the Samples , see the current version is0.8.0

1.2.2. Contents analysis

• Because I used SpringCloud the set, did not use dubbo, so I did not run on dubbo of the
  

• Look it an example of the directory structure, we also know it can probably run it is valid

• Of primary concern here is actually a document, although pitiful, but I found a can directly point here

1.2.3 Runspringboot-mybatis

• My first run was the least dependent springboot-mybatisonly need to open a server, configure the local database, and set up tables can run, this is actually nothing to say, I run very smoothly, just run the directory sql directory under the all_in_one.sqlinside of all the statements, it will help you build the database insert basic data , as the end of the download service can click here to download
• window system directly above the server unzip the bag double-click operation seata-server.bat, liunx system run seata-server.shthis, it is enabled by default 8091port configuration files in /confthe directory, major changes are needed file.confand refistry.conf, after will be talked about

• List of Figures except under the following commondo not need to run, the other four are up and running, and then call localhost:8084/api/business/purchase/commit, check the database will find the order table to add data, storage table deducted inventory, account was deducted money
  

• Then the case is a test rollback
  

• As the interface calls localhost:8084/api/business/purchase/rollback, look at accountthe system
  

• Is actually a special user thrown exceptions caused by a rollback, you can be marked with a breakpoint before throwing an exception, then you will find to run, go to the database, inventory has been deducted, the order has been added, undo_logthe table has the recording , which involves its rollback principle, probably say, has been running through sql logging, succeeded delete the log, failed to roll back the log data, and then delete the log, so anyway, log it should not exist, if there is an abnormal downtime help system, start and should continue to be rolled back
  

1.2.4. Small summary

• By fast start, we can quickly run success of its demo, the pit is currently not met, but the default configuration so far we have used, have not seen the basic how it changes the configuration, see next configuration Seata file

1.3. SeataConfiguration File

1.3.1. registry.conf

• Official documents address
• He specifically mentioned sentence here

service.vgroup_mapping this configuration, in the default Spring Cloud $ {spring.application.name} -fescar-service-group, may be covered by the specified application.properties spring.cloud.alibaba.seata.tx-service-group this property , but it must be consistent and file.conf in, otherwise it will promptno available server to connect

• Finally, I run springcloud-eureak-seatawhen she encountered, and here it reflects the lack of documentation, I think each of the following examples should put a Notes document it, and hold each example below, wiki Rideau write about is good too, we are not developers, to seata not familiar, especially its configuration, the two main profiles registry.confand file.confthe various systems are present, but the description of its precautions and only Sampleproject in the quick-integration-with-spring-cloud.mddocuments mentioned in the sentence, for just the contact person for this project very friendly

• This file is used to specify the registry and configuration files , default is the local file storage, so the beginning of mybatis project we did not feel the need to rely on, then the above phrase is also successful with crooked remind me, so I did not think service brought out problems

• The file can choose file 、nacos 、eureka、redis、zk、consul、etcd3、sofathese registries, specify file、nacos 、apollo、zk、consul、etcd3these configuration files are stored, so as to remind eureka type with a registry change here remember

1.3.2. file.conf

• Used to specify the TC (Transaction Coordinator) related attributes
• It also wrote 如果使用注册中心也可以将配置添加到配置中心, I have to Tucao, I use apolloas a distribution center, how to put this configuration file apolloto go, there is also no documentation, then I have to look up the source code to study

• What is important here used in the demo in property service.vgroup_mapping.my_test_tx_group, the value of this key is equivalent to the service name of the server, in effect Eureka, equivalent to the following
  

• Eureka useless if this registry, we will need to fill in the server address, the corresponding service.default.grouplistvalues
  

• As there are n number of other properties Sorry, no documents, in addition to understand from the literal meaning, you do not know to look at the source code, anyway, I do not write the document
  

1.4. SpringCloud integration

1.4.1. Pit

• Ready to run springcloud-eureka-seata, I first of all run, reported no available server to connectsince been re-check the configuration where the pair is not? Tangled for a long time, I finally react, this is not the server
• In the provider modifies type = "eureka"or incorrect report, but I have been debug, I know that is not the original problem, the ultimate solution is run locally, the service side of file.confthe service.default.grouplist = "172.16.100.141:8091"address into the network address , do not use 127.0.0.1, step two Hang finally commissioning a success, the demo is successfully up and running, after the challenge is to integrate into your own project
• Here what should Tucao, in addition to quick start, no other integrated document, which is in addition to references jar package also need to do the only reference is the Sampleproject, this project integrated pit tomorrow continue to step up free

1.5 Summary

• The technical idea of ​​the project is good, distributed transaction mode is also more than one (although its documentation to demonstrate such a kind), I believe it will continue to put good ideas incorporated Ali distributed transaction, or worth the wait