浅谈WebSocket WebSocket是在HTML5基础上单个TCP连接上进行全双工通讯的协议,只要浏览器和服务器进行一次握手,就可以建立一条快速通道,两者就可以实现数据互传了。说白了,就是打破了传统的http协议的无状态传输(只能浏览器请求,服务端响应),websocket全双工通讯,就是浏览器和服务器进行一次握手,浏览器可以随时给服务器发送信息,服务器也可以随时主动发送信息给浏览器了。对webSocket原理有兴趣的客官,可以自行百度。 2.环境搭建 因为是根据项目的需求来的,所以这里我只介绍在SpringBoot下使用WebSocket的其中一种实现【STOMP协议】。因此整个工程涉及websocket使用的大致框架为SpringBoot+Maven+websocket,其他框架的基础搭建,我这里就不说了,相信各位也都很熟悉,我就直接集成websocket了。 在pox.xml加上对springBoot对WebSocket的支持: <!-- webSocket --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency> 这样SpringBoot就和WebSocket集成好了,我们就可以直接使用SpringBoot提供对WebSocket操作的API了 3.编码实现 ①在Spring上下文中添加对WebSocket的配置 import org.springframework.context.annotation.Configuration; import org.springframework.messaging.simp.config.MessageBrokerRegistry; import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer; import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker; import org.springframework.web.socket.config.annotation.StompEndpointRegistry; /** * 配置WebSocket */ @Configuration //注解开启使用STOMP协议来传输基于代理(message broker)的消息,这时控制器支持使用@MessageMapping,就像使用@RequestMapping一样 @EnableWebSocketMessageBroker public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer{ @Override //注册STOMP协议的节点(endpoint),并映射指定的url public void registerStompEndpoints(StompEndpointRegistry registry) { //注册一个STOMP的endpoint,并指定使用SockJS协议 registry.addEndpoint("/endpointOyzc").setAllowedOrigins("*").withSockJS(); } @Override //配置消息代理(Message Broker) public void configureMessageBroker(MessageBrokerRegistry registry) { //点对点应配置一个/user消息代理,广播式应配置一个/topic消息代理 registry.enableSimpleBroker("/topic","/user"); //点对点使用的订阅前缀(客户端订阅路径上会体现出来),不设置的话,默认也是/user/ registry.setUserDestinationPrefix("/user"); } } 介绍以上几个相关的注解和方法: 1.@EnableWebSocketMessageBroker:开启使用STOMP协议来传输基于代理(message broker)的消息,这时控制器支持使用@MessageMapping,就像使用@RequestMapping一样。 2.AbstractWebSocketMessageBrokerConfigurer:继承WebSocket消息代理的类,配置相关信息。 3.registry.addEndpoint("/endpointOyzc").setAllowedOrigins("*").withSockJS(); 添加一个访问端点“/endpointGym”,客户端打开双通道时需要的url,允许所有的域名跨域访问,指定使用SockJS协议。 4. registry.enableSimpleBroker("/topic","/user"); 配置一个/topic广播消息代理和“/user”一对一消息代理 5. registry.setUserDestinationPrefix("/user");点对点使用的订阅前缀(客户端订阅路径上会体现出来),不设置的话,默认也是/user/ ②实现服务器主动向客户端推送消息 SpringBoot封装得太好,webSocket用起来太简单(好处:用起来方便,坏处:你不知道底层实现) 1.一对多的实现: 先上后台java的代码 package com.cheng.sbjm.boot; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.messaging.simp.SimpMessagingTemplate; import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Controller; import com.cheng.sbjm.domain.User; @Controller public class WebSocketController { @Autowired private SimpMessagingTemplate template; //广播推送消息 @Scheduled(fixedRate = 10000) public void sendTopicMessage() { System.out.println("后台广播推送!"); User user=new User(); user.setUserName("oyzc"); user.setAge(10); this.template.convertAndSend("/topic/getResponse",user); } } 简单介绍一下 1.SimpMessagingTemplate:SpringBoot提供操作WebSocket的对象 2.@Scheduled(fixedRate = 10000):为了测试,定时10S执行这个方法,向客户端推送 3.template.convertAndSend("/topic/getResponse",new AricResponse("后台实时推送:,Oyzc!")); :直接向前端推送消息。 3.1参数一:客户端监听指定通道时,设定的访问服务器的URL 3.2参数二:发送的消息(可以是对象、字符串等等) 在上客户端的代码(PC现代浏览器) html页面: <!DOCTYPE html> <html> <head> <title>websocket.html</title> <meta name="keywords" content="keyword1,keyword2,keyword3"> <meta name="description" content="this is my page"> <meta name="content-type" content="text/html" charset="UTF-8"> <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> </head> <body> <div> <p id="response"></p> </div> <!-- 独立JS --> <script type="text/javascript" src="jquery.min.js" charset="utf-8"></script> <script type="text/javascript" src="webSocket.js" charset="utf-8"></script> <script type="text/javascript" src="sockjs.min.js" charset="utf-8"></script> <script type="text/javascript" src="stomp.js" charset="utf-8"></script> </body> </html> JS代码[webSocket.js] var stompClient = null; //加载完浏览器后 调用connect(),打开双通道 $(function(){ //打开双通道 connect() }) //强制关闭浏览器 调用websocket.close(),进行正常关闭 window.onunload = function() { disconnect() } function connect(){ var socket = new SockJS('http://127.0.0.1:9091/sbjm-cheng/endpointOyzc'); //连接SockJS的endpoint名称为"endpointOyzc" stompClient = Stomp.over(socket);//使用STMOP子协议的WebSocket客户端 stompClient.connect({},function(frame){//连接WebSocket服务端 console.log('Connected:' + frame); //通过stompClient.subscribe订阅/topic/getResponse 目标(destination)发送的消息 stompClient.subscribe('/topic/getResponse',function(response){ showResponse(JSON.parse(response.body)); }); }); } //关闭双通道 function disconnect(){ if(stompClient != null) { stompClient.disconnect(); } console.log("Disconnected"); } function showResponse(message){ var response = $("#response"); response.append("<p>"+message.userName+"</p>"); } 值得注意的是,只需要在连接服务器注册端点endPoint时,写访问服务器的全路径URL: new SockJS('http://127.0.0.1:9091/sbjm-cheng/endpointOyzc'); 其他监听指定服务器广播的URL不需要写全路径 stompClient.subscribe('/topic/getResponse',function(response){ showResponse(JSON.parse(response.body)); }); 2.一对一的实现 先上后台java的代码 package com.cheng.sbjm.boot; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.messaging.simp.SimpMessagingTemplate; import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Controller; import com.cheng.sbjm.domain.User; @Controller public class WebSocketController { @Autowired private SimpMessagingTemplate template; //一对一推送消息 @Scheduled(fixedRate = 10000) public void sendQueueMessage() { System.out.println("后台一对一推送!"); User user=new User(); user.setUserId(1); user.setUserName("oyzc"); user.setAge(10); this.template.convertAndSendToUser(user.getUserId()+"","/queue/getResponse",user); } } 简单介绍一下: 1.SimpMessagingTemplate:SpringBoot提供操作WebSocket的对象 2.@Scheduled(fixedRate = 10000):为了测试,定时10S执行这个方法,向客户端推送 3.template.convertAndSendToUser(user.getUserId()+"","/queue/getResponse",user); :直接向前端推送消息。 3.1参数一:指定客户端接收的用户标识(一般用用户ID) 3.2参数二:客户端监听指定通道时,设定的访问服务器的URL(客户端访问URL跟广播有些许不同) 3.3参数三:向目标发送消息体(实体、字符串等等) 在上客户端的代码(PC现代浏览器) html页面: <!DOCTYPE html> <html> <head> <title>websocket.html</title> <meta name="keywords" content="keyword1,keyword2,keyword3"> <meta name="description" content="this is my page"> <meta name="content-type" content="text/html" charset="UTF-8"> <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> <!-- 独立css --> </head> <body> <div> <p id="response"></p> </div> <!-- 独立JS --> <script type="text/javascript" src="jquery.min.js" charset="utf-8"></script> <script type="text/javascript" src="webSocket.js" charset="utf-8"></script> <script type="text/javascript" src="sockjs.min.js" charset="utf-8"></script> <script type="text/javascript" src="stomp.js" charset="utf-8"></script> </body> </html> JS代码[webSocket.js] var stompClient = null; //加载完浏览器后 调用connect(),打开双通道 $(function(){ //打开双通道 connect() }) //强制关闭浏览器 调用websocket.close(),进行正常关闭 window.onunload = function() { disconnect() } function connect(){ var userId=1; var socket = new SockJS('http://127.0.0.1:9091/sbjm-cheng/endpointOyzc'); //连接SockJS的endpoint名称为"endpointOyzc" stompClient = Stomp.over(socket);//使用STMOP子协议的WebSocket客户端 stompClient.connect({},function(frame){//连接WebSocket服务端 console.log('Connected:' + frame); //通过stompClient.subscribe订阅/topic/getResponse 目标(destination)发送的消息 stompClient.subscribe('/user/' + userId + '/queue/getResponse',function(response){ var code=JSON.parse(response.body); showResponse(code) }); }); } //关闭双通道 function disconnect(){ if(stompClient != null) { stompClient.disconnect(); } console.log("Disconnected"); } function showResponse(message){ var response = $("#response"); response.append("<p>只有userID为"+message.userId+"的人才能收到</p>"); } 与广播不同的是,在指定通道的URL加个用户标识: stompClient.subscribe('/user/' + userId + '/queue/getResponse',function(response){ var code=JSON.parse(response.body); showResponse(code) }); 该标识userId必须与服务器推送消息时设置的用户标识一致 以上就是实现服务器实时向客户端推送消息,各位可以按照各自的需求进行配合使用。 ③实现客户端与服务器之间的直接交互,聊天室demo[在②的基础上添加了一些代码] 1.在webSocket配置中,增加2个WebSocket的代理 package com.cheng.sbjm.configure; import org.springframework.context.annotation.Configuration; import org.springframework.messaging.simp.config.MessageBrokerRegistry; import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer; import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker; import org.springframework.web.socket.config.annotation.StompEndpointRegistry; /** * 配置WebSocket */ @Configuration //注解开启使用STOMP协议来传输基于代理(message broker)的消息,这时控制器支持使用@MessageMapping,就像使用@RequestMapping一样 @EnableWebSocketMessageBroker public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer{ @Override //注册STOMP协议的节点(endpoint),并映射指定的url public void registerStompEndpoints(StompEndpointRegistry registry) { //注册一个STOMP的endpoint,并指定使用SockJS协议 registry.addEndpoint("/endpointOyzc").setAllowedOrigins("*").withSockJS(); } @Override //配置消息代理(Message Broker) public void configureMessageBroker(MessageBrokerRegistry registry) { //点对点应配置一个/user消息代理,广播式应配置一个/topic消息代理,群发(mass),单独聊天(alone) registry.enableSimpleBroker("/topic","/user","/mass","/alone"); //点对点使用的订阅前缀(客户端订阅路径上会体现出来),不设置的话,默认也是/user/ registry.setUserDestinationPrefix("/user"); } } "/mass"用以代理群发消息 "/alone"用以代码一对一聊天 2.java后台实现 package com.cheng.sbjm.boot; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.messaging.handler.annotation.MessageMapping; import org.springframework.messaging.handler.annotation.SendTo; import org.springframework.messaging.simp.SimpMessagingTemplate; import org.springframework.stereotype.Controller; import com.cheng.sbjm.onput.ChatRoomRequest; import com.cheng.sbjm.onput.ChatRoomResponse; @Controller public class WebSocketController { @Autowired private SimpMessagingTemplate template; //客户端主动发送消息到服务端,服务端马上回应指定的客户端消息 //类似http无状态请求,但是有质的区别 //websocket可以从服务器指定发送哪个客户端,而不像http只能响应请求端 //群发 @MessageMapping("/massRequest") //SendTo 发送至 Broker 下的指定订阅路径 @SendTo("/mass/getResponse") public ChatRoomResponse mass(ChatRoomRequest chatRoomRequest){ //方法用于群发测试 System.out.println("name = " + chatRoomRequest.getName()); System.out.println("chatValue = " + chatRoomRequest.getChatValue()); ChatRoomResponse response=new ChatRoomResponse(); response.setName(chatRoomRequest.getName()); response.setChatValue(chatRoomRequest.getChatValue()); return response; } //单独聊天 @MessageMapping("/aloneRequest") public ChatRoomResponse alone(ChatRoomRequest chatRoomRequest){ //方法用于一对一测试 System.out.println("userId = " + chatRoomRequest.getUserId()); System.out.println("name = " + chatRoomRequest.getName()); System.out.println("chatValue = " + chatRoomRequest.getChatValue()); ChatRoomResponse response=new ChatRoomResponse(); response.setName(chatRoomRequest.getName()); response.setChatValue(chatRoomRequest.getChatValue()); this.template.convertAndSendToUser(chatRoomRequest.getUserId()+"","/alone/getResponse",response); return response; } } 简单介绍新的注解一下: 一.@MessageMapping("/massRequest"):类似与@RequestMapping,客户端请求服务器的URL,前提是双方端点已经打开 二.@SendTo("/mass/getResponse"):作用跟convertAndSend类似,广播发给与该通道相连的客户端 其他已经在前面解释过了。 3.html代码 <!DOCTYPE html> <html> <head> <title>login.html</title> <meta name="keywords" content="keyword1,keyword2,keyword3"> <meta name="description" content="this is my page"> <meta name="content-type" content="text/html" charset="UTF-8"> <!--<link rel="stylesheet" type="text/css" href="./styles.css">--> <!-- 独立css --> <link rel="stylesheet" type="text/css" href="chatroom.css"> </head> <body> <div> <div style="float:left;width:40%"> <p>请选择你是谁:</p> <select id="selectName" onchange="sendAloneUser();"> <option value="1">请选择</option> <option value="ALong">ALong</option> <option value="AKan">AKan</option> <option value="AYuan">AYuan</option> <option value="ALai">ALai</option> <option value="ASheng">ASheng</option> </select> <div class="chatWindow"> <p style="color:darkgrey">群聊:</p> <section id="chatRecord" class="chatRecord"> <p id="titleval" style="color:#CD2626;"></p> </section> <section class="sendWindow"> <textarea name="sendChatValue" id="sendChatValue" class="sendChatValue"></textarea> <input type="button" name="sendMessage" id="sendMessage" class="sendMessage" onclick="sendMassMessage()" value="发送"> </section> </div> </div> <div style="float:right; width:40%"> <p>请选择你要发给谁:</p> <select id="selectName2"> <option value="1">请选择</option> <option value="ALong">ALong</option> <option value="AKan">AKan</option> <option value="AYuan">AYuan</option> <option value="ALai">ALai</option> <option value="ASheng">ASheng</option> </select> <div class="chatWindow"> <p style="color:darkgrey">单独聊:</p> <section id="chatRecord2" class="chatRecord"> <p id="titleval" style="color:#CD2626;"></p> </section> <section class="sendWindow"> <textarea name="sendChatValue2" id="sendChatValue2" class="sendChatValue"></textarea> <input type="button" name="sendMessage" id="sendMessage" class="sendMessage" onclick="sendAloneMessage()" value="发送"> </section> </div> </div> </div> <!-- 独立JS --> <script type="text/javascript" src="jquery.min.js" charset="utf-8"></script> <script type="text/javascript" src="chatroom.js" charset="utf-8"></script> <script type="text/javascript" src="sockjs.min.js" charset="utf-8"></script> <script type="text/javascript" src="stomp.js" charset="utf-8"></script> </body> </html> JS代码[chatroom.js]: var stompClient = null; //加载完浏览器后 调用connect(),打开双通道 $(function(){ //打开双通道 connect() }) //强制关闭浏览器 调用websocket.close(),进行正常关闭 window.onunload = function() { disconnect() } //打开双通道 function connect(){ var socket = new SockJS('http://172.16.0.56:9091/sbjm-cheng/endpointOyzc'); //连接SockJS的endpoint名称为"endpointAric" stompClient = Stomp.over(socket);//使用STMOP子协议的WebSocket客户端 stompClient.connect({},function(frame){//连接WebSocket服务端 console.log('Connected:' + frame); //广播接收信息 stompTopic(); }); } //关闭双通道 function disconnect(){ if(stompClient != null) { stompClient.disconnect(); } console.log("Disconnected"); } //广播(一对多) function stompTopic(){ //通过stompClient.subscribe订阅/topic/getResponse 目标(destination)发送的消息(广播接收信息) stompClient.subscribe('/mass/getResponse',function(response){ var message=JSON.parse(response.body); //展示广播的接收的内容接收 var response = $("#chatRecord"); response.append("<p><span>"+message.name+":</span><span>"+message.chatValue+"</span></p>"); }); } //列队(一对一) function stompQueue(){ var userId=$("#selectName").val(); alert("监听:"+userId) //通过stompClient.subscribe订阅/topic/getResponse 目标(destination)发送的消息(队列接收信息) stompClient.subscribe('/user/' + userId + '/alone/getResponse',function(response){ var message=JSON.parse(response.body); //展示一对一的接收的内容接收 var response = $("#chatRecord2"); response.append("<p><span>"+message.name+":</span><span>"+message.chatValue+"</span></p>"); }); } //选择发送给谁的时候触发连接服务器 function sendAloneUser(){ stompQueue(); } //群发 function sendMassMessage(){ var postValue={}; var chatValue=$("#sendChatValue"); var userName=$("#selectName").val(); postValue.name=userName; postValue.chatValue=chatValue.val(); if(userName==1||userName==null){ alert("请选择你是谁!"); return; } if(chatValue==""||userName==null){ alert("不能发送空消息!"); return; } stompClient.send("/massRequest",{},JSON.stringify(postValue)); chatValue.val(""); } //单独发 function sendAloneMessage(){ var postValue={}; var chatValue=$("#sendChatValue2"); var userName=$("#selectName").val(); var sendToId=$("#selectName2").val(); var response = $("#chatRecord2"); postValue.name=userName; postValue.chatValue=chatValue.val(); postValue.userId=sendToId; if(userName==1||userName==null){ alert("请选择你是谁!"); return; } if(sendToId==1||sendToId==null){ alert("请选择你要发给谁!"); return; } if(chatValue==""||userName==null){ alert("不能发送空消息!"); return; } stompClient.send("/aloneRequest",{},JSON.stringify(postValue)); response.append("<p><span>"+userName+":</span><span>"+chatValue.val()+"</span></p>"); chatValue.val(""); } chatroom.css .chatWindow{ width: 100%; height: 500px; border: 1px solid blue; } .chatRecord{ width: 100%; height: 400px; border-bottom: 1px solid blue; line-height:20px; overflow:auto; overflow-x:hidden; } .sendWindow{ width: 100%; height: 200px; } .sendChatValue{ width: 90%; height: 40px; !
来源:https://www.cnblogs.com/leigepython/p/10510768.html