什么是WebSocket

WebSocket是一种在单个TCP连接上进行全双工通信的协议 …

为什么要实现握手监控管理

如果说，连接随意创建，不管的话，会存在错误，broken pipe

表面看单纯报错，并没什么功能缺陷等，但实际，请求数增加，容易导致系统奔溃。这边画重点。

出现原因有很多种，目前我这边出现的原因，是因为客户端已关闭连接，服务端还持续推送导致。

如何使用

下面将使用springboot集成的webSocket

导入Maven

首先SpringBoot版本

<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.8.RELEASE</version> </parent>

 

集成websocket

// 加个web集成吧 <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency>

Java代码

Config配置

首先，我们需要重写WebSocketHandlerDecoratorFactory

主要用来监控客户端握手连接进来以及挥手关闭连接

代码

需要一个管理Socket的类

package com.li.manager; import lombok.extern.slf4j.Slf4j; import org.springframework.web.socket.WebSocketSession; import java.util.concurrent.ConcurrentHashMap; /** * socket管理器 */ @Slf4j public class SocketManager { private static ConcurrentHashMap<String, WebSocketSession> manager = new ConcurrentHashMap<String, WebSocketSession>(); public static void add(String key, WebSocketSession webSocketSession) { log.info("新添加webSocket连接 {} ", key); manager.put(key, webSocketSession); } public static void remove(String key) { log.info("移除webSocket连接 {} ", key); manager.remove(key); } public static WebSocketSession get(String key) { log.info("获取webSocket连接 {}", key); return manager.get(key); } }

 

package com.li.factory; import com.li.manager.SocketManager; import lombok.extern.slf4j.Slf4j; import org.springframework.stereotype.Component; import org.springframework.web.socket.CloseStatus; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.WebSocketSession; import org.springframework.web.socket.handler.WebSocketHandlerDecorator; import org.springframework.web.socket.handler.WebSocketHandlerDecoratorFactory; import java.security.Principal; /** * 服务端和客户端在进行握手挥手时会被执行 */ @Component @Slf4j public class WebSocketDecoratorFactory implements WebSocketHandlerDecoratorFactory { @Override public WebSocketHandler decorate(WebSocketHandler handler) { return new WebSocketHandlerDecorator(handler) { @Override public void afterConnectionEstablished(WebSocketSession session) throws Exception { log.info("有人连接啦 sessionId = {}", session.getId()); Principal principal = session.getPrincipal(); if (principal != null) { log.info("key = {} 存入", principal.getName()); // 身份校验成功，缓存socket连接 SocketManager.add(principal.getName(), session); } super.afterConnectionEstablished(session); } @Override public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception { log.info("有人退出连接啦 sessionId = {}", session.getId()); Principal principal = session.getPrincipal(); if (principal != null) { // 身份校验成功，移除socket连接 SocketManager.remove(principal.getName()); } super.afterConnectionClosed(session, closeStatus); } }; } }

 

注意：以上session变量，需要注意两点，一个是getId(),一个是getPrincipal().getName()

getId() ： 返回的是唯一的会话标识符。

getPrincipal() : 经过身份验证，返回Principal实例，未经过身份验证，返回null

Principal: 委托人的抽象概念,可以是公司id，名字，用户唯一识别token等

当你按上面代码使用，你会发现getPrincipal()返回null，为什么？这边还需要重写一个DefaultHandshakeHandler

代码

package com.li.handler; import lombok.extern.slf4j.Slf4j; import org.springframework.http.server.ServerHttpRequest; import org.springframework.http.server.ServletServerHttpRequest; import org.springframework.stereotype.Component; import org.springframework.util.StringUtils; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.server.support.DefaultHandshakeHandler; import javax.servlet.http.HttpServletRequest; import java.security.Principal; import java.util.Map; /** * 我们可以通过请求信息，比如token、或者session判用户是否可以连接，这样就能够防范非法用户 */ @Slf4j @Component public class PrincipalHandshakeHandler extends DefaultHandshakeHandler { @Override protected Principal determineUser(ServerHttpRequest request, WebSocketHandler wsHandler, Map<String, Object> attributes) { /** * 这边可以按你的需求，如何获取唯一的值，既unicode * 得到的值，会在监听处理连接的属性中，既WebSocketSession.getPrincipal().getName() * 也可以自己实现Principal() */ if (request instanceof ServletServerHttpRequest) { ServletServerHttpRequest servletServerHttpRequest = (ServletServerHttpRequest) request; HttpServletRequest httpRequest = servletServerHttpRequest.getServletRequest(); /** * 这边就获取你最熟悉的陌生人,携带参数，你可以cookie，请求头，或者url携带，这边我采用url携带 */ final String token = httpRequest.getParameter("token"); if (StringUtils.isEmpty(token)) { return null; } return new Principal() { @Override public String getName() { return token; } }; } return null; } }

 

需要的东西都有了，那准备装载吧

代码

package com.li.config; import com.li.factory.WebSocketDecoratorFactory; import com.li.handler.PrincipalHandshakeHandler; import org.springframework.beans.factory.annotation.Autowired; 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; import org.springframework.web.socket.config.annotation.WebSocketTransportRegistration; /** * WebSocketConfig配置 */ @Configuration @EnableWebSocketMessageBroker public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer { @Autowired private WebSocketDecoratorFactory webSocketDecoratorFactory; @Autowired private PrincipalHandshakeHandler principalHandshakeHandler; @Override public void registerStompEndpoints(StompEndpointRegistry registry) { /** * myUrl表示 你前端到时要对应url映射 */ registry.addEndpoint("/myUrl") .setAllowedOrigins("*") .setHandshakeHandler(principalHandshakeHandler) .withSockJS(); } @Override public void configureMessageBroker(MessageBrokerRegistry registry) { /** * queue 点对点 * topic 广播 * user 点对点前缀 */ registry.enableSimpleBroker("/queue", "/topic"); registry.setUserDestinationPrefix("/user"); } @Override public void configureWebSocketTransport(WebSocketTransportRegistration registration) { registration.addDecoratorFactory(webSocketDecoratorFactory); super.configureWebSocketTransport(registration); } }

 

终于完成了

最后，来一个通过http请求，将其发送到客户端

代码

package com.li.controller; import com.li.manager.SocketManager; import lombok.extern.slf4j.Slf4j; 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.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.socket.WebSocketSession; import java.util.Map; @RestController @Slf4j public class TestController { @Autowired private SimpMessagingTemplate template; /** * 服务器指定用户进行推送,需要前端开通 var socket = new SockJS(host+'/myUrl' + '?token=1234'); */ @RequestMapping("/sendUser") public void sendUser(String token) { log.info("token = {} ,对其发送您好", token); WebSocketSession webSocketSession = SocketManager.get(token); if (webSocketSession != null) { /** * 主要防止broken pipe */ template.convertAndSendToUser(token, "/queue/sendUser", "您好"); } } /** * 广播，服务器主动推给连接的客户端 */ @RequestMapping("/sendTopic") public void sendTopic() { template.convertAndSend("/topic/sendTopic", "大家晚上好"); } /** * 客户端发消息，服务端接收 * * @param message */ // 相当于RequestMapping @MessageMapping("/sendServer") public void sendServer(String message) { log.info("message:{}", message); } /** * 客户端发消息，大家都接收，相当于直播说话 * * @param message * @return */ @MessageMapping("/sendAllUser") @SendTo("/topic/sendTopic") public String sendAllUser(String message) { // 也可以采用template方式 return message; } /** * 点对点用户聊天，这边需要注意，由于前端传过来json数据，所以使用@RequestBody * 这边需要前端开通var socket = new SockJS(host+'/myUrl' + '?token=4567'); token为指定name * @param map */ @MessageMapping("/sendMyUser") public void sendMyUser(@RequestBody Map<String, String> map) { log.info("map = {}", map); WebSocketSession webSocketSession = SocketManager.get(map.get("name")); if (webSocketSession != null) { log.info("sessionId = {}", webSocketSession.getId()); template.convertAndSendToUser(map.get("name"), "/queue/sendUser", map.get("message")); } } }

 

前端代码

可以直接启动

<!DOCTYPE html> <html> <head> <meta charset="UTF-8" /> <title>Spring Boot WebSocket+广播式</title> </head> <body> <noscript> <h2 style="color:#ff0000">貌似你的浏览器不支持websocket</h2> </noscript> <div> <div> <button id="connect" onclick="connect()">连接</button> <button id="disconnect" onclick="disconnect();">断开连接</button> </div> <div id="conversationDiv"> <label>输入你的名字</label> <input type="text" id="name" /> <br> <label>输入消息</label> <input type="text" id="messgae" /> <button id="send" onclick="send();">发送</button> <p id="response"></p> </div> </div> <script src="https://cdn.bootcss.com/sockjs-client/1.1.4/sockjs.min.js"></script> <script src="https://cdn.bootcss.com/stomp.js/2.3.3/stomp.min.js"></script> <script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.min.js"></script> <script type="text/javascript"> var stompClient = null; //gateway网关的地址 var host="http://127.0.0.1:8888"; function setConnected(connected) { document.getElementById('connect').disabled = connected; document.getElementById('disconnect').disabled = !connected; document.getElementById('conversationDiv').style.visibility = connected ? 'visible' : 'hidden'; $('#response').html(); } // SendUser *********************************************** function connect() { //地址+端点路径，构建websocket链接地址,注意，对应config配置里的addEndpoint var socket = new SockJS(host+'/myUrl' + '?token=4567'); stompClient = Stomp.over(socket); stompClient.connect({}, function(frame) { setConnected(true); console.log('Connected:' + frame); //监听的路径以及回调 stompClient.subscribe('/user/queue/sendUser', function(response) { showResponse(response.body); }); }); } /* function connect() { //地址+端点路径，构建websocket链接地址,注意，对应config配置里的addEndpoint var socket = new SockJS(host+'/myUrl'); stompClient = Stomp.over(socket); stompClient.connect({}, function(frame) { setConnected(true); console.log('Connected:' + frame); //监听的路径以及回调 stompClient.subscribe('/topic/sendTopic', function(response) { showResponse(response.body); }); }); }*/ function disconnect() { if (stompClient != null) { stompClient.disconnect(); } setConnected(false); console.log("Disconnected"); } function send() { var name = $('#name').val(); var message = $('#messgae').val(); /*//发送消息的路径,由客户端发送消息到服务端 stompClient.send("/sendServer", {}, message); */ /*// 发送给所有广播sendTopic的人,客户端发消息，大家都接收，相当于直播说话 注：连接需开启 /topic/sendTopic stompClient.send("/sendAllUser", {}, message); */ /* 这边需要注意，需要启动不同的前端html进行测试，需要改不同token ，例如 token=1234，token=4567 * 然后可以通过写入name 为token 进行指定用户发送 */ stompClient.send("/sendMyUser", {}, JSON.stringify({name:name,message:message})); } function showResponse(message) { var response = $('#response'); response.html(message); } </script> </body> </html> View Code

 

注意，记得要自己尝试，好记性不如烂笔头。

版权声明：本文为不会代码的小白原创文章，转载需添加小白地址 ： https://www.ccode.live/bertonlee/list/8?from=art

源代码：https://github.com/bertonlee/webSocket-01 欢迎Star

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转载于:https://www.cnblogs.com/xswz/p/10314351.html

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