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README
GPL-2.0

分布式秒杀系统

交流群:529135840

开发环境

JDK1.7、Maven、Mysql、Eclipse、SpringBoot1.5.10、zookeeper3.4.6、kafka_2.11、redis-2.8.4、curator-2.10.0

启动说明

  • 启动前 请配置 application.properties 中相关redis、zk以及kafka相关地址,建议在Linux下安装使用。

  • 数据库脚本位于 src/main/resource/sql 下面,启动前请自行导入。

  • 配置完成,运行Application中的main方法,访问 http://localhost:8080/seckill/swagger-ui.html 进行API测试。

  • 秒杀商品页:http://localhost:8080/seckill ,部分功能待完成。

  • 本测试案例单纯为了学习,某些案例并不适用于生产环境,大家根据所需自行调整。

测试入口

http://localhost:8080/seckill/swagger-ui.html

API

项目截图

秒杀商品列表

商品详情页

友情提示

由于工作原因,项目正在完善中(仅供参考),随时更新日志,有疑问请留言或者加群

项目介绍

SpringBoot开发案例从0到1构建分布式秒杀系统,项目案例基本成型,逐步完善中。

输入图片说明

秒杀场景

秒杀场景无非就是多个用户在同时抢购一件或者多件商品,专用词汇就是所谓的高并发。现实中经常被大家喜闻乐见的场景,一群大妈抢购打折鸡蛋的画面一定不会陌生,如此场面让服务员大姐很无奈,赶上不要钱了。

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业务特点

  • 瞬间高并发、电脑旁边的小哥哥、小姐姐们如超市哄抢的大妈一般,疯狂的点着鼠标
  • 库存少、便宜、稀缺限量,值得大家去抢购,如苹果肾,小米粉,锤子粉(理解万岁)

用户规模

用户规模可大可小,几百或者上千人的活动单体架构足以可以应付,简单的加锁、进程内队列就可以轻松搞定。一旦上升到百万、千万级别的规模就要考虑分布式集群来应对瞬时高并发。

秒杀架构

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架构层级

  • 一般商家在做活动的时候,经常会遇到各种不怀好意的DDOS攻击(利用无辜的吃瓜群众夺取资源),导致真正的我们无法获得服务!所以说高防IP还是很有必要的。

  • 搞活动就意味着人多,接入SLB,对多台云服务器进行流量分发,可以通过流量分发扩展应用系统对外的服务能力,通过消除单点故障提升应用系统的可用性。

  • 基于SLB价格以及灵活性考虑后面我们接入Nginx做限流分发,来保障后端服务的正常运行。

  • 后端秒杀业务逻辑,基于Redis 或者 Zookeeper 分布式锁,Kafka 或者 Redis 做消息队列,DRDS数据库中间件实现数据的读写分离。

优化思路

  • 分流、分流、分流,重要的事情说三遍,再牛逼的机器也抵挡不住高级别的并发。

  • 限流、限流、限流,毕竟秒杀商品有限,防刷的前提下没有绝对的公平,根据每个服务的负载能力,设定流量极限。

  • 缓存、缓存、缓存、尽量不要让大量请求穿透到DB层,活动开始前商品信息可以推送至分布式缓存。

  • 异步、异步、异步,分析并识别出可以异步处理的逻辑,比如日志,缩短系统响应时间。

  • 主备、主备、主备,如果有条件做好主备容灾方案也是非常有必要的(参考某年锤子的活动被攻击)。

  • 最后,为了支撑更高的并发,追求更好的性能,可以对服务器的部署模型进行优化,部分请求走正常的秒杀流程,部分请求直接返回秒杀失败,缺点是开发部署时需要维护两套逻辑。

分层优化

  • 前端优化:活动开始前生成静态商品页面推送缓存和CDN,静态文件(JS/CSS)请求推送至文件服务器和CDN。
  • 网络优化:如果是全国用户,最好是BGP多线机房,减少网络延迟。
  • 应用服务优化:Nginx最佳配置、Tomcat连接池优化、数据库配置优化、数据库连接池优化。

全链路压测

  • 分析需压测业务场景涉及系统
  • 协调各个压测系统资源并搭建压测环境
  • 压测数据隔离以及监控(响应时间、吞吐量、错误率等数据以图表形式实时显示)
  • 压测结果统计(平均响应时间、平均吞吐量等数据以图表形式在测试结束后显示)
  • 优化单个系统性能、关联流程以及整个业务流程

整个压测优化过程就是一个不断优化不断改进的过程,事先通过测试不断发现问题,优化系统,避免问题,指定应急方案,才能让系统的稳定性和性能都得到质的提升。

数据采集监控

分布式跟踪工具Pinpoint初探

Grafana+Telegraf+Influxdb监控Tomcat集群方案

Grafana+Prometheus系统监控之MySql

Grafana+Prometheus系统监控之Redis

Grafana+Prometheus系统监控之SpringBoot

代码案例

可能秒杀架构原理大家都懂,网上也有不少实现方式,但大多都是文字的描述,告诉你如何如何,什么加锁、缓存、队列之类。但很少全面有的案例告诉你如何去做,既然是从0到1,希望以下代码案例可以帮助到你。当然最终落实到生产,还有很长的路要走,要根据自己的业务进行编码,实施并部署。

你将会在代码案例中学到以下知识:

  • 如何搭建SpringBoot微服务
  • ThreadPoolExecutor线程池的使用
  • ReentrantLock和Synchronized的使用场景
  • 数据库锁机制(悲观锁、乐观锁)
  • 分布式锁(RedissLock、Zookeeper)
  • 进程内消息队列(LinkedBlockingQueue、ArrayBlockingQueue、ConcurrentLinkedQueue)
  • 分布式消息队列(Redis、Kafka)
  • AOP实现切面锁
  • Disruptor高效队列
  • 商品详情页静态化

代码结构:

      
├─src
│  ├─main
│  │  ├─java
│  │  │  └─com
│  │  │      └─itstyle
│  │  │          └─seckill
│  │  │              │  Application.java
│  │  │              │  
│  │  │              ├─common
│  │  │              │  ├─aop
│  │  │              │  │      LockAspect.java
│  │  │              │  │      Servicelock.java
│  │  │              │  │      
│  │  │              │  ├─api
│  │  │              │  │      SwaggerConfig.java
│  │  │              │  │      
│  │  │              │  ├─config
│  │  │              │  │      IndexController.java
│  │  │              │  │      SpringUtil.java
│  │  │              │  │      
│  │  │              │  ├─dynamicquery
│  │  │              │  │      DynamicQuery.java
│  │  │              │  │      DynamicQueryImpl.java
│  │  │              │  │      NativeQueryResultEntity.java
│  │  │              │  │      
│  │  │              │  ├─entity
│  │  │              │  │      Result.java
│  │  │              │  │      Seckill.java
│  │  │              │  │      SuccessKilled.java
│  │  │              │  │      
│  │  │              │  ├─enums
│  │  │              │  │      SeckillStatEnum.java
│  │  │              │  │      
│  │  │              │  ├─interceptor
│  │  │              │  │      MyAdapter.java
│  │  │              │  │      
│  │  │              │  ├─lock
│  │  │              │  │      LockDemo.java
│  │  │              │  │      
│  │  │              │  └─redis
│  │  │              │          RedisConfig.java
│  │  │              │          RedisUtil.java
│  │  │              │          
│  │  │              ├─distributedlock
│  │  │              │  ├─redis
│  │  │              │  │      RedissLockDemo.java
│  │  │              │  │      RedissLockUtil.java
│  │  │              │  │      RedissonAutoConfiguration.java
│  │  │              │  │      RedissonProperties.java
│  │  │              │  │      
│  │  │              │  └─zookeeper
│  │  │              │          ZkLockUtil.java
│  │  │              │          
│  │  │              ├─queue
│  │  │              │  ├─disruptor
│  │  │              │  │      DisruptorUtil.java
│  │  │              │  │      SeckillEvent.java
│  │  │              │  │      SeckillEventConsumer.java
│  │  │              │  │      SeckillEventFactory.java
│  │  │              │  │      SeckillEventMain.java
│  │  │              │  │      SeckillEventProducer.java
│  │  │              │  │      
│  │  │              │  ├─jvm
│  │  │              │  │      SeckillQueue.java
│  │  │              │  │      TaskRunner.java
│  │  │              │  │      
│  │  │              │  ├─kafka
│  │  │              │  │      KafkaConsumer.java
│  │  │              │  │      KafkaSender.java
│  │  │              │  │      
│  │  │              │  └─redis
│  │  │              │          RedisConsumer.java
│  │  │              │          RedisSender.java
│  │  │              │          RedisSubListenerConfig.java
│  │  │              │          
│  │  │              ├─repository
│  │  │              │      SeckillRepository.java
│  │  │              │      
│  │  │              ├─service
│  │  │              │  │  ICreateHtmlService.java
│  │  │              │  │  ISeckillDistributedService.java
│  │  │              │  │  ISeckillService.java
│  │  │              │  │  
│  │  │              │  └─impl
│  │  │              │          CreateHtmlServiceImpl.java
│  │  │              │          SeckillDistributedServiceImpl.java
│  │  │              │          SeckillServiceImpl.java
│  │  │              │          
│  │  │              └─web
│  │  │                      CreateHtmlController.java
│  │  │                      SeckillController.java
│  │  │                      SeckillDistributedController.java
│  │  │                      
│  │  ├─resources
│  │  │  │  application.properties
│  │  │  │  logback-spring.xml
│  │  │  │  
│  │  │  ├─sql
│  │  │  │      seckill.sql
│  │  │  │      
│  │  │  ├─static
│  │  │  │  ├─goods
│  │  │  │  │  ├─images
│  │  │  │  │  │  │      
│  │  │  │  │  │  └─shopdetail
│  │  │  │  │  │          
│  │  │  │  │  ├─js
│  │  │  │  │  │      common.js
│  │  │  │  │  │      jquery-1.9.1.min.js
│  │  │  │  │  │      
│  │  │  │  │  └─style
│  │  │  │  │          shopdetail.css
│  │  │  │  │          
│  │  │  │  ├─iview
│  │  │  │  │  │  iview.css
│  │  │  │  │  │  iview.min.js
│  │  │  │  │  │  
│  │  │  │  │  └─fonts
│  │  │  │  │          ionicons.eot
│  │  │  │  │          ionicons.svg
│  │  │  │  │          ionicons.ttf
│  │  │  │  │          ionicons.woff
│  │  │  │  │          
│  │  │  │  └─template
│  │  │  │          goods.flt
│  │  │  │          
│  │  │  └─templates
│  │  │          1000.html
│  │  │          1001.html
│  │  │          1002.html
│  │  │          1003.html
│  │  │          index.html
│  │  │          

单机

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分布式锁应该具备哪些条件

  • 在分布式系统环境下,一个方法在同一时间只能被一个机器的一个线程执行;
  • 高可用的获取锁与释放锁;
  • 高性能的获取锁与释放锁;
  • 具备可重入特性;
  • 具备锁失效机制,防止死锁;
  • 具备非阻塞锁特性,即没有获取到锁将直接返回获取锁失败。

分布式锁

  • 基于数据库实现分布式锁;
  • 基于缓存(Redis等)实现分布式锁;
  • 基于Zookeeper实现分布式锁;

思考改进

  • 如何防止单个用户重复秒杀下单?
  • 如何防止恶意调用秒杀接口?
  • 如果用户秒杀成功,一直不支付该怎么办?
  • 消息队列处理完成后,如果异步通知给用户秒杀成功?
  • 如何保障 Redis、Zookeeper 、Kafka 服务的正常运行(高可用)?
  • 高并发下秒杀业务如何做到不影响其他业务(隔离性)?

可供参考

淘宝大秒系统设计详解

SpringBoot开发案例从0到1构建分布式秒杀系统

SpringBoot开发案例之整合Kafka实现消息队列

从构建分布式秒杀系统聊聊Threadpool线程池

从构建分布式秒杀系统聊聊Disruptor高性能队列

从构建分布式秒杀系统聊聊商品详情页静态化

构建分布式秒杀系统聊聊Lock锁使用中的坑

从构建分布式秒杀系统聊聊限流特技

从构建分布式秒杀系统聊聊WebSocket推送通知

从构建分布式秒杀系统聊聊分布式锁

Nginx学习之负载均衡

Nginx学习之如何防止流量攻击

Nginx学习之缓存配置

Nginx学习之HTTP/2.0配置

企业云解析DNS

Linux下搭建ZooKeeper集群

linux下redis设置密码登录

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If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Program at all. For example, if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program. If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply and the section as a whole is intended to apply in other circumstances. It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system, which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice. This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License. 8. If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License. 9. The Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation. 10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally. NO WARRANTY 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. END OF TERMS AND CONDITIONS How to Apply These Terms to Your New Programs If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms. To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. {description} Copyright (C) 2018 小柒2012 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Also add information on how to contact you by electronic and paper mail. If the program is interactive, make it output a short notice like this when it starts in an interactive mode: Gnomovision version 69, Copyright (C) year name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program. You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names: Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision' (which makes passes at compilers) written by James Hacker. {signature of Ty Coon}, 1 April 1989 Ty Coon, President of Vice This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License.

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从0到1构建分布式秒杀系统,脱离案例讲架构都是耍流氓 展开 收起
Java
GPL-2.0
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