手写MQ框架（二）-服务端实现
一、起航
书接上文->手写MQ框架（一）-准备启程
本着从无到有，从有到优的原则，所以计划先通过web实现功能，然后再优化改写为socket的形式。
1、关于技术选型
web框架使用了之前写的gmvc框架（手写MVC框架（一）-再出发），消息存储采用存在数据库的方式，使用的框架也是前段时间写的gdao（手写DAO框架（一）-从“1”开始 ）。
2、项目搭建
项目本来是单项目的形式，但是考虑到将服务端、客户端分开不是很友好，所以采用了maven父子模块的形式。
其中，父pom配置如下：
<?xml version="1.0" encoding="UTF-8"?> <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 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.shuimutong</groupId> <artifactId>gmq</artifactId> <version>${global.version}</version> <packaging>pom</packaging> <url>http://maven.apache.org</url> <modules> <module>gmq-server</module> <module>gmq-client</module> </modules> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <global.version>0.0.1-SNAPSHOT</global.version> <fastjson.version>1.2.60</fastjson.version> <gdao.version>2.0.0-SNAPSHOT</gdao.version> <gmvc.version>1.0.1-SNAPSHOT</gmvc.version> <gutil.version>0.0.2-SNAPSHOT</gutil.version> </properties> <dependencyManagement> <dependencies> <dependency> <groupId>me.lovegao</groupId> <artifactId>gdao</artifactId> <version>${gdao.version}</version> </dependency> <dependency> <groupId>com.shuimutong</groupId> <artifactId>gmvc</artifactId> <version>${gmvc.version}</version> </dependency> <dependency> <groupId>com.shuimutong</groupId> <artifactId>gutil</artifactId> <version>${gutil.version}</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>${fastjson.version}</version> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> <version>3.4</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.16</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>1.6.1</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.6.2</version> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.7.0</version> <configuration> <target>1.8</target> <source>1.8</source> </configuration> </plugin> </plugins> </build> </project>
这次要说的mq服务端pom配置如下：
<?xml version="1.0"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>com.shuimutong</groupId> <artifactId>gmq</artifactId> <version>${global.version}</version> </parent> <groupId>com.shuimutong</groupId> <artifactId>gmq-server</artifactId> <packaging>war</packaging> <version>${global.version}</version> <name>gmq-server</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <scope>test</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> </dependency> <dependency> <groupId>me.lovegao</groupId> <artifactId>gdao</artifactId> </dependency> <dependency> <groupId>com.shuimutong</groupId> <artifactId>gmvc</artifactId> <exclusions> <exclusion> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> </dependency> </dependencies> <build> <finalName>com.shuimutong.gmq_server</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.7.0</version> <configuration> <target>1.8</target> <source>1.8</source> </configuration> </plugin> </plugins> </build> </project>
项目依赖的gdao（https://gitee.com/simpleha/gdao.git）、gmvc（https://gitee.com/simpleha/gmvc.git）、gutil（https://gitee.com/simpleha/gutil.git）需要先clone到本地并编译到maven仓库。
二、接口梳理
1、SyncController
在发布消息或者订阅消息前，我们需要先新增topic。我这里把新增topic和后面的发布订阅消息分开了，主要是考虑到两个类被访问频率有差别，分开后有利于以后的针对优化。
具体实现如下：
package com.shuimutong.gmq.server.controller; import java.util.List; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.alibaba.fastjson.JSONObject; import com.shuimutong.gmq.server.bean.enums.RequestParamEnum; import com.shuimutong.gmq.server.bean.enums.ResponseCodeEnum; import com.shuimutong.gmq.server.bean.vo.ResponseDataVo; import com.shuimutong.gmq.server.bean.vo.UriDescVo; import com.shuimutong.gmq.server.exception.ServiceException; import com.shuimutong.gmq.server.service.SyncService; import com.shuimutong.gmq.server.service.TopicService; import com.shuimutong.gmvc.annotation.XAutowired; import com.shuimutong.gmvc.annotation.XController; import com.shuimutong.gmvc.annotation.XRequestMapping; import com.shuimutong.gmvc.util.RequestResolveUtil; /** * 非消息信息同步controller * @ClassName: MessageController * @Description:(这里用一句话描述这个类的作用) * @author: 水木桶 * @date: 2019年10月20日 下午9:45:47 * @Copyright: 2019 [水木桶] All rights reserved. */ @XController @XRequestMapping("/sync") public class SyncController { private final static Logger log = LoggerFactory.getLogger(SyncController.class); @XAutowired private TopicService topicService; @XAutowired private SyncService syncService; /** * 获取uri说明 * @param request * @param reponse */ @XRequestMapping("/getPath") public void getPath(HttpServletRequest request, HttpServletResponse reponse) { List<UriDescVo> uriList = syncService.listUriDesc(); ResponseDataVo responseData = new ResponseDataVo(ResponseCodeEnum.OK, uriList); RequestResolveUtil.returnJson(request, reponse, JSONObject.toJSONString(responseData)); } /** * 新增topic * @param request * @param reponse */ @XRequestMapping("/addTopic") public void addTopic(HttpServletRequest request, HttpServletResponse reponse) { ResponseDataVo responseData = null; String topic = request.getParameter(RequestParamEnum.TOPIC.getParamName()); if(StringUtils.isBlank(topic)) { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "主题为空"); } else { try { boolean addState = topicService.addTopic(topic); if(addState) { responseData = new ResponseDataVo(ResponseCodeEnum.OK, "添加成功"); } else { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "主题已存在"); } } catch (ServiceException e) { log.error("addTopicException," + topic, e); responseData = new ResponseDataVo(ResponseCodeEnum.SERVER_ERROR); } } RequestResolveUtil.returnJson(request, reponse, JSONObject.toJSONString(responseData)); } }
其中getPath()暂时没有用到，以后用到再讨论吧。
2、MessageController
消息的topic创建之后，就是消息的发布和订阅了。
具体实现如下：
package com.shuimutong.gmq.server.controller; import java.util.List; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.alibaba.fastjson.JSONObject; import com.shuimutong.gmq.server.bean.SystemConstant; import com.shuimutong.gmq.server.bean.dos.TopicDo; import com.shuimutong.gmq.server.bean.enums.RequestParamEnum; import com.shuimutong.gmq.server.bean.enums.ResponseCodeEnum; import com.shuimutong.gmq.server.bean.vo.ResponseDataVo; import com.shuimutong.gmq.server.exception.ServiceException; import com.shuimutong.gmq.server.service.MessageService; import com.shuimutong.gmq.server.service.TopicService; import com.shuimutong.gmvc.annotation.XAutowired; import com.shuimutong.gmvc.annotation.XController; import com.shuimutong.gmvc.annotation.XRequestMapping; import com.shuimutong.gmvc.util.RequestResolveUtil; import com.shuimutong.guti.bean.TwoTuple; /** * 发消息、收消息controller * @ClassName: MessageController * @Description:(这里用一句话描述这个类的作用) * @author: 水木桶 * @date: 2019年10月20日 下午9:45:47 * @Copyright: 2019 [水木桶] All rights reserved. */ @XController @XRequestMapping(SystemConstant.STR_URL_MESSAGE) public class MessageController { private final static Logger log = LoggerFactory.getLogger(MessageController.class); @XAutowired private MessageService messageService; @XAutowired private TopicService topicService; /** * 获取消息 * @param request * @param reponse */ @XRequestMapping(SystemConstant.STR_URL_GET_MESSAGE) public void getMessage(HttpServletRequest request, HttpServletResponse reponse) { ResponseDataVo responseData = null; String topic = request.getParameter(RequestParamEnum.TOPIC.getParamName()); String offsetStr = request.getParameter(RequestParamEnum.OFFSET.getParamName()); String sizeStr = request.getParameter(RequestParamEnum.SIZE.getParamName()); if(StringUtils.isBlank(topic) || !StringUtils.isNumeric(offsetStr) || !StringUtils.isNumeric(sizeStr)) { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "主题为空或者数字非法"); } else { int offset = Integer.parseInt(offsetStr); int size = Integer.parseInt(sizeStr); if(offset < 0 || size < 1) { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "数字异常"); } else { try { TopicDo topicDo = topicService.findByTopic(topic); if(topicDo == null) { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "主题不存在"); } else { List<TwoTuple<Long, String>> list = messageService.listMessage(topic, offset, size); responseData = new ResponseDataVo(ResponseCodeEnum.OK, list); } } catch (ServiceException e) { log.error("getMessageException", e); responseData = new ResponseDataVo(ResponseCodeEnum.SERVER_ERROR); } } } RequestResolveUtil.returnJson(request, reponse, JSONObject.toJSONString(responseData)); } /** * 生产方发送消息到服务端 * @param request * @param reponse */ @XRequestMapping(SystemConstant.STR_URL_SEND_MESSAGE) public void sendMessage(HttpServletRequest request, HttpServletResponse reponse) { ResponseDataVo responseData = null; String topic = request.getParameter(RequestParamEnum.TOPIC.getParamName()); String message = request.getParameter(RequestParamEnum.MESSAGE.getParamName()); if(StringUtils.isBlank(topic) || StringUtils.isBlank(message)) { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "主题或者消息为空"); } else { try { TopicDo topicDo = topicService.findByTopic(topic); if(topicDo == null) { responseData = new ResponseDataVo(ResponseCodeEnum.PARAM_ERROR, "主题不存在"); } else { messageService.saveMessage(topic, message); responseData = new ResponseDataVo(ResponseCodeEnum.OK); } } catch (ServiceException e) { log.error("sendMessageException", e); responseData = new ResponseDataVo(ResponseCodeEnum.SERVER_ERROR); } } RequestResolveUtil.returnJson(request, reponse, JSONObject.toJSONString(responseData)); } }
3、CacheController
设计的mq的消费形式是拉的形式。采用拉的形式，就需要客户端自己去计数，消费到哪了。
所以这里增加了这个缓存接口，提供kv存储的功能。数据存储在数据库里。
代码请移步到下文的gitee连接查看。
有了上面这几个接口，就可以实现简单的发布消息、订阅消息的功能了，当然是手动的方式获取。
三、相关表
既然为了分享，资料就得提供全。所以这里就列一下关联的数据库表结构。
1、主题表
CREATE TABLE `gmq_topic` ( `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键', `topic` varchar(255) NOT NULL DEFAULT '' COMMENT '主题', `create_time` timestamp NOT NULL DEFAULT current_timestamp() ON UPDATE current_timestamp() COMMENT '创建时间', PRIMARY KEY (`id`), UNIQUE KEY `uniq_idx_topic` (`topic`) USING BTREE ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='gmq-主题表';
2、消息表
CREATE TABLE `gmq_message` ( `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键', `topic` varchar(255) NOT NULL DEFAULT '' COMMENT '主题', `message_body` text NOT NULL COMMENT '消息内容', `create_time` timestamp NOT NULL DEFAULT current_timestamp() ON UPDATE current_timestamp() COMMENT '创建时间', PRIMARY KEY (`id`), KEY `idx_id_topic` (`id`,`topic`) USING BTREE ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='存储的消息';
3、kv表
CREATE TABLE `gmq_message` ( `id` bigint(20) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键', `topic` varchar(255) NOT NULL DEFAULT '' COMMENT '主题', `message_body` text NOT NULL COMMENT '消息内容', `create_time` timestamp NOT NULL DEFAULT current_timestamp() ON UPDATE current_timestamp() COMMENT '创建时间', PRIMARY KEY (`id`), KEY `idx_id_topic` (`id`,`topic`) USING BTREE ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 COMMENT='存储的消息';
四、总结
主要功能就是上面些。回头看来也不算很多，但是具体实现过程中真是曲折重重，这其中一部分是框架的原因。
所以上篇博客到这篇博客中间，我不仅写完了这个项目，其实还顺便修复了框架使用中遇到的一些问题。比如bigint类型的数据查出来真的是BigDecimal，而不是long。
gmq项目主要包括两块，上面介绍的是服务端，接下来会介绍客户端。
最后，附上代码地址：https://gitee.com/simpleha/gmq.git
下一篇，客户端的实现->手写MQ框架（三）-客户端实现
