内容简介:在上一篇文章(其实,要解决这个问题就需要实现分布式WebSocket,而分布式WebSocket一般可以通过以下两种方案来实现:在下面的示例中,我将根据相对简单的方案一来是实现,具体实现方式如下:
在上一篇文章( www.zifangsky.cn/1359.html )中我介绍了服务端如何给指定用户的客户端发送消息,并如何处理对方不在线的情况。在这篇文章中我们继续思考另外一个重要的问题,那就是: 如果我们的项目是分布式环境,登录的用户被Nginx的反向代理分配到多个不同服务器,那么在其中一个服务器建立了WebSocket连接的用户如何给在另外一个服务器上建立了WebSocket连接的用户发送消息呢 ?
其实,要解决这个问题就需要实现分布式WebSocket,而分布式WebSocket一般可以通过以下两种方案来实现:
- 方案一:将消息(<用户id,消息内容>)统一推送到一个消息队列(Redis、Kafka等)的的topic,然后每个应用节点都订阅这个topic,在接收到WebSocket消息后取出这个消息的“ 消息接收者的用户ID/用户名 ”,然后再比对自身是否存在相应用户的连接,如果存在则推送消息,否则丢弃接收到的这个消息(这个消息接收者所在的应用节点会处理)
- 方案二:在用户建立WebSocket连接后,使用 Redis 缓存记录用户的WebSocket建立在哪个应用节点上,然后同样使用消息队列将消息推送到接收者所在的应用节点上面(实现上比方案一要复杂,但是网络流量会更低)
在下面的示例中,我将根据相对简单的方案一来是实现,具体实现方式如下:
(1)定义一个WebSocket Channel枚举类:
package cn.zifangsky.mqwebsocket.enums; import org.apache.commons.lang3.StringUtils; /** * WebSocket Channel枚举类 * * @author zifangsky * @date 2018/10/16 * @since 1.0.0 */ public enum WebSocketChannelEnum { //测试使用的简易点对点聊天 CHAT("CHAT", "测试使用的简易点对点聊天", "/topic/reply"); WebSocketChannelEnum(String code, String description, String subscribeUrl) { this.code = code; this.description = description; this.subscribeUrl = subscribeUrl; } /** * 唯一CODE */ private String code; /** * 描述 */ private String description; /** * WebSocket客户端订阅的URL */ private String subscribeUrl; public String getCode() { return code; } public String getDescription() { return description; } public String getSubscribeUrl() { return subscribeUrl; } /** * 通过CODE查找枚举类 */ public static WebSocketChannelEnum fromCode(String code){ if(StringUtils.isNoneBlank(code)){ for(WebSocketChannelEnum channelEnum : values()){ if(channelEnum.code.equals(code)){ return channelEnum; } } } return null; } } 复制代码
(2)配置基于Redis的消息队列:
关于Redis实现的消息队列可以参考我之前的这篇文章: www.zifangsky.cn/1347.html
需要注意的是,在大中型正式项目中并不推荐使用Redis实现的消息队列,因为经过测试它并不是特别可靠,所以应该考虑使用 Kafka
、 rabbitMQ
等专业的消息队列中间件(PS:据说Redis 5.0全新的数据结构 Streams
极大增强了Redis的消息队列功能?)
package cn.zifangsky.mqwebsocket.config; import cn.zifangsky.mqwebsocket.mq.MessageReceiver; import com.fasterxml.jackson.annotation.JsonAutoDetect; import com.fasterxml.jackson.annotation.PropertyAccessor; import com.fasterxml.jackson.databind.ObjectMapper; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.autoconfigure.condition.ConditionalOnClass; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.data.redis.connection.RedisClusterConfiguration; import org.springframework.data.redis.connection.RedisConnectionFactory; import org.springframework.data.redis.connection.jedis.JedisConnectionFactory; import org.springframework.data.redis.core.RedisTemplate; import org.springframework.data.redis.listener.PatternTopic; import org.springframework.data.redis.listener.RedisMessageListenerContainer; import org.springframework.data.redis.listener.adapter.MessageListenerAdapter; import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer; import org.springframework.data.redis.serializer.StringRedisSerializer; import redis.clients.jedis.JedisCluster; import redis.clients.jedis.JedisPoolConfig; import java.util.Arrays; /** * Redis相关配置 * * @author zifangsky * @date 2018/7/30 * @since 1.0.0 */ @Configuration @ConditionalOnClass({JedisCluster.class}) public class RedisConfig { @Value("${spring.redis.timeout}") private String timeOut; @Value("${spring.redis.cluster.nodes}") private String nodes; @Value("${spring.redis.cluster.max-redirects}") private int maxRedirects; @Value("${spring.redis.jedis.pool.max-active}") private int maxActive; @Value("${spring.redis.jedis.pool.max-wait}") private int maxWait; @Value("${spring.redis.jedis.pool.max-idle}") private int maxIdle; @Value("${spring.redis.jedis.pool.min-idle}") private int minIdle; @Value("${spring.redis.message.topic-name}") private String topicName; @Bean public JedisPoolConfig jedisPoolConfig(){ JedisPoolConfig config = new JedisPoolConfig(); config.setMaxTotal(maxActive); config.setMaxIdle(maxIdle); config.setMinIdle(minIdle); config.setMaxWaitMillis(maxWait); return config; } @Bean public RedisClusterConfiguration redisClusterConfiguration(){ RedisClusterConfiguration configuration = new RedisClusterConfiguration(Arrays.asList(nodes)); configuration.setMaxRedirects(maxRedirects); return configuration; } /** * JedisConnectionFactory */ @Bean public JedisConnectionFactory jedisConnectionFactory(RedisClusterConfiguration configuration,JedisPoolConfig jedisPoolConfig){ return new JedisConnectionFactory(configuration,jedisPoolConfig); } /** * 使用Jackson序列化对象 */ @Bean public Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer(){ Jackson2JsonRedisSerializer<Object> serializer = new Jackson2JsonRedisSerializer<Object>(Object.class); ObjectMapper objectMapper = new ObjectMapper(); objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY); objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL); serializer.setObjectMapper(objectMapper); return serializer; } /** * RedisTemplate */ @Bean public RedisTemplate<String, Object> redisTemplate(JedisConnectionFactory factory, Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer){ RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>(); redisTemplate.setConnectionFactory(factory); //字符串方式序列化KEY StringRedisSerializer stringRedisSerializer = new StringRedisSerializer(); redisTemplate.setKeySerializer(stringRedisSerializer); redisTemplate.setHashKeySerializer(stringRedisSerializer); //JSON方式序列化VALUE redisTemplate.setValueSerializer(jackson2JsonRedisSerializer); redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer); redisTemplate.afterPropertiesSet(); return redisTemplate; } /** * 消息监听器 */ @Bean MessageListenerAdapter messageListenerAdapter(MessageReceiver messageReceiver, Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer){ //消息接收者以及对应的默认处理方法 MessageListenerAdapter messageListenerAdapter = new MessageListenerAdapter(messageReceiver, "receiveMessage"); //消息的反序列化方式 messageListenerAdapter.setSerializer(jackson2JsonRedisSerializer); return messageListenerAdapter; } /** * message listener container */ @Bean RedisMessageListenerContainer container(RedisConnectionFactory connectionFactory , MessageListenerAdapter messageListenerAdapter){ RedisMessageListenerContainer container = new RedisMessageListenerContainer(); container.setConnectionFactory(connectionFactory); //添加消息监听器 container.addMessageListener(messageListenerAdapter, new PatternTopic(topicName)); return container; } } 复制代码
需要注意的是,这里使用的配置如下所示:
spring: ... #redis redis: cluster: nodes: namenode22:6379,datanode23:6379,datanode24:6379 max-redirects: 6 timeout: 300000 jedis: pool: max-active: 8 max-wait: 100000 max-idle: 8 min-idle: 0 #自定义的监听的TOPIC路径 message: topic-name: topic-test 复制代码
(3)定义一个Redis消息的处理者:
package cn.zifangsky.mqwebsocket.mq; import cn.zifangsky.mqwebsocket.enums.WebSocketChannelEnum; import cn.zifangsky.mqwebsocket.model.websocket.RedisWebsocketMsg; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.messaging.simp.SimpMessagingTemplate; import org.springframework.messaging.simp.user.SimpUser; import org.springframework.messaging.simp.user.SimpUserRegistry; import org.springframework.stereotype.Component; import java.text.MessageFormat; /** * Redis中的WebSocket消息的处理者 * * @author zifangsky * @date 2018/10/16 * @since 1.0.0 */ @Component public class MessageReceiver { private final Logger logger = LoggerFactory.getLogger(getClass()); @Autowired private SimpMessagingTemplate messagingTemplate; @Autowired private SimpUserRegistry userRegistry; /** * 处理WebSocket消息 */ public void receiveMessage(RedisWebsocketMsg redisWebsocketMsg) { logger.info(MessageFormat.format("Received Message: {0}", redisWebsocketMsg)); //1. 取出用户名并判断是否连接到当前应用节点的WebSocket SimpUser simpUser = userRegistry.getUser(redisWebsocketMsg.getReceiver()); if(simpUser != null && StringUtils.isNoneBlank(simpUser.getName())){ //2. 获取WebSocket客户端的订阅地址 WebSocketChannelEnum channelEnum = WebSocketChannelEnum.fromCode(redisWebsocketMsg.getChannelCode()); if(channelEnum != null){ //3. 给WebSocket客户端发送消息 messagingTemplate.convertAndSendToUser(redisWebsocketMsg.getReceiver(), channelEnum.getSubscribeUrl(), redisWebsocketMsg.getContent()); } } } } 复制代码
(4)在Controller中发送WebSocket消息:
package cn.zifangsky.mqwebsocket.controller; import cn.zifangsky.mqwebsocket.common.Constants; import cn.zifangsky.mqwebsocket.common.SpringContextUtils; import cn.zifangsky.mqwebsocket.enums.ExpireEnum; import cn.zifangsky.mqwebsocket.enums.WebSocketChannelEnum; import cn.zifangsky.mqwebsocket.model.User; import cn.zifangsky.mqwebsocket.model.websocket.HelloMessage; import cn.zifangsky.mqwebsocket.model.websocket.RedisWebsocketMsg; import cn.zifangsky.mqwebsocket.service.RedisService; import cn.zifangsky.mqwebsocket.utils.JsonUtils; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.messaging.simp.SimpMessagingTemplate; import org.springframework.messaging.simp.user.SimpUser; import org.springframework.messaging.simp.user.SimpUserRegistry; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.PostMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import javax.annotation.Resource; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import java.text.MessageFormat; import java.util.HashMap; import java.util.List; import java.util.Map; /** * 测试{@link org.springframework.messaging.simp.SimpMessagingTemplate}类的基本用法 * @author zifangsky * @date 2018/10/10 * @since 1.0.0 */ @Controller @RequestMapping(("/wsTemplate")) public class RedisMessageController { private final Logger logger = LoggerFactory.getLogger(getClass()); @Value("${spring.redis.message.topic-name}") private String topicName; @Autowired private SimpMessagingTemplate messagingTemplate; @Autowired private SimpUserRegistry userRegistry; @Resource(name = "redisServiceImpl") private RedisService redisService; /** * 给指定用户发送WebSocket消息 */ @PostMapping("/sendToUser") @ResponseBody public String chat(HttpServletRequest request) { //消息接收者 String receiver = request.getParameter("receiver"); //消息内容 String msg = request.getParameter("msg"); HttpSession session = SpringContextUtils.getSession(); User loginUser = (User) session.getAttribute(Constants.SESSION_USER); HelloMessage resultData = new HelloMessage(MessageFormat.format("{0} say: {1}", loginUser.getUsername(), msg)); this.sendToUser(loginUser.getUsername(), receiver, WebSocketChannelEnum.CHAT.getSubscribeUrl(), JsonUtils.toJson(resultData)); return "ok"; } /** * 给指定用户发送消息,并处理接收者不在线的情况 * @param sender 消息发送者 * @param receiver 消息接收者 * @param destination 目的地 * @param payload 消息正文 */ private void sendToUser(String sender, String receiver, String destination, String payload){ SimpUser simpUser = userRegistry.getUser(receiver); //如果接收者存在,则发送消息 if(simpUser != null && StringUtils.isNoneBlank(simpUser.getName())){ messagingTemplate.convertAndSendToUser(receiver, destination, payload); } //如果接收者在线,则说明接收者连接了集群的其他节点,需要通知接收者连接的那个节点发送消息 else if(redisService.isSetMember(Constants.REDIS_WEBSOCKET_USER_SET, receiver)){ RedisWebsocketMsg<String> redisWebsocketMsg = new RedisWebsocketMsg<>(receiver, WebSocketChannelEnum.CHAT.getCode(), payload); redisService.convertAndSend(topicName, redisWebsocketMsg); } //否则将消息存储到redis,等用户上线后主动拉取未读消息 else{ //存储消息的Redis列表名 String listKey = Constants.REDIS_UNREAD_MSG_PREFIX + receiver + ":" + destination; logger.info(MessageFormat.format("消息接收者{0}还未建立WebSocket连接,{1}发送的消息【{2}】将被存储到Redis的【{3}】列表中", receiver, sender, payload, listKey)); //存储消息到Redis中 redisService.addToListRight(listKey, ExpireEnum.UNREAD_MSG, payload); } } /** * 拉取指定监听路径的未读的WebSocket消息 * @param destination 指定监听路径 * @return java.util.Map<java.lang.String,java.lang.Object> */ @PostMapping("/pullUnreadMessage") @ResponseBody public Map<String, Object> pullUnreadMessage(String destination){ Map<String, Object> result = new HashMap<>(); try { HttpSession session = SpringContextUtils.getSession(); //当前登录用户 User loginUser = (User) session.getAttribute(Constants.SESSION_USER); //存储消息的Redis列表名 String listKey = Constants.REDIS_UNREAD_MSG_PREFIX + loginUser.getUsername() + ":" + destination; //从Redis中拉取所有未读消息 List<Object> messageList = redisService.rangeList(listKey, 0, -1); result.put("code", "200"); if(messageList !=null && messageList.size() > 0){ //删除Redis中的这个未读消息列表 redisService.delete(listKey); //将数据添加到返回集,供前台页面展示 result.put("result", messageList); } }catch (Exception e){ result.put("code", "500"); result.put("msg", e.getMessage()); } return result; } } 复制代码
(5)其他拦截器处理WebSocket连接相关问题:
i)AuthHandshakeInterceptor:
package cn.zifangsky.mqwebsocket.interceptor.websocket; import cn.zifangsky.mqwebsocket.common.Constants; import cn.zifangsky.mqwebsocket.common.SpringContextUtils; import cn.zifangsky.mqwebsocket.model.User; import cn.zifangsky.mqwebsocket.service.RedisService; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.http.server.ServerHttpRequest; import org.springframework.http.server.ServerHttpResponse; import org.springframework.stereotype.Component; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.server.HandshakeInterceptor; import javax.annotation.Resource; import javax.servlet.http.HttpSession; import java.text.MessageFormat; import java.util.Map; /** * 自定义{@link org.springframework.web.socket.server.HandshakeInterceptor},实现“需要登录才允许连接WebSocket” * * @author zifangsky * @date 2018/10/11 * @since 1.0.0 */ @Component public class AuthHandshakeInterceptor implements HandshakeInterceptor { private final Logger logger = LoggerFactory.getLogger(getClass()); @Resource(name = "redisServiceImpl") private RedisService redisService; @Override public boolean beforeHandshake(ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse, WebSocketHandler webSocketHandler, Map<String, Object> map) throws Exception { HttpSession session = SpringContextUtils.getSession(); User loginUser = (User) session.getAttribute(Constants.SESSION_USER); if(redisService.isSetMember(Constants.REDIS_WEBSOCKET_USER_SET, loginUser.getUsername())){ logger.error("同一个用户不准建立多个连接WebSocket"); return false; }else if(loginUser == null || StringUtils.isBlank(loginUser.getUsername())){ logger.error("未登录系统,禁止连接WebSocket"); return false; }else{ logger.debug(MessageFormat.format("用户{0}请求建立WebSocket连接", loginUser.getUsername())); return true; } } @Override public void afterHandshake(ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse, WebSocketHandler webSocketHandler, Exception e) { } } 复制代码
ii)MyHandshakeHandler:
package cn.zifangsky.mqwebsocket.interceptor.websocket; import cn.zifangsky.mqwebsocket.common.Constants; import cn.zifangsky.mqwebsocket.common.SpringContextUtils; import cn.zifangsky.mqwebsocket.model.User; import cn.zifangsky.mqwebsocket.service.RedisService; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.http.server.ServerHttpRequest; import org.springframework.stereotype.Component; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.server.support.DefaultHandshakeHandler; import javax.annotation.Resource; import javax.servlet.http.HttpSession; import java.security.Principal; import java.text.MessageFormat; import java.util.Map; /** * 自定义{@link org.springframework.web.socket.server.support.DefaultHandshakeHandler},实现“生成自定义的{@link java.security.Principal}” * * @author zifangsky * @date 2018/10/11 * @since 1.0.0 */ @Component public class MyHandshakeHandler extends DefaultHandshakeHandler{ private final Logger logger = LoggerFactory.getLogger(getClass()); @Resource(name = "redisServiceImpl") private RedisService redisService; @Override protected Principal determineUser(ServerHttpRequest request, WebSocketHandler wsHandler, Map<String, Object> attributes) { HttpSession session = SpringContextUtils.getSession(); User loginUser = (User) session.getAttribute(Constants.SESSION_USER); if(loginUser != null){ logger.debug(MessageFormat.format("WebSocket连接开始创建Principal,用户:{0}", loginUser.getUsername())); //1. 将用户名存到Redis中 redisService.addToSet(Constants.REDIS_WEBSOCKET_USER_SET, loginUser.getUsername()); //2. 返回自定义的Principal return new MyPrincipal(loginUser.getUsername()); }else{ logger.error("未登录系统,禁止连接WebSocket"); return null; } } } 复制代码
iii)MyChannelInterceptor:
package cn.zifangsky.mqwebsocket.interceptor.websocket; import cn.zifangsky.mqwebsocket.common.Constants; import cn.zifangsky.mqwebsocket.service.RedisService; import org.apache.commons.lang3.StringUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.messaging.Message; import org.springframework.messaging.MessageChannel; import org.springframework.messaging.simp.stomp.StompCommand; import org.springframework.messaging.simp.stomp.StompHeaderAccessor; import org.springframework.messaging.support.ChannelInterceptor; import org.springframework.stereotype.Component; import javax.annotation.Resource; import java.security.Principal; import java.text.MessageFormat; /** * 自定义{@link org.springframework.messaging.support.ChannelInterceptor},实现断开连接的处理 * * @author zifangsky * @date 2018/10/10 * @since 1.0.0 */ @Component public class MyChannelInterceptor implements ChannelInterceptor{ private final Logger logger = LoggerFactory.getLogger(getClass()); @Resource(name = "redisServiceImpl") private RedisService redisService; @Override public void afterSendCompletion(Message<?> message, MessageChannel channel, boolean sent, Exception ex) { StompHeaderAccessor accessor = StompHeaderAccessor.wrap(message); StompCommand command = accessor.getCommand(); //用户已经断开连接 if(StompCommand.DISCONNECT.equals(command)){ String user = ""; Principal principal = accessor.getUser(); if(principal != null && StringUtils.isNoneBlank(principal.getName())){ user = principal.getName(); //从Redis中移除用户 redisService.removeFromSet(Constants.REDIS_WEBSOCKET_USER_SET, user); }else{ user = accessor.getSessionId(); } logger.debug(MessageFormat.format("用户{0}的WebSocket连接已经断开", user)); } } } 复制代码
(6)WebSocket相关配置:
package cn.zifangsky.mqwebsocket.config; import cn.zifangsky.mqwebsocket.interceptor.websocket.MyHandshakeHandler; import cn.zifangsky.mqwebsocket.interceptor.websocket.AuthHandshakeInterceptor; import cn.zifangsky.mqwebsocket.interceptor.websocket.MyChannelInterceptor; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.annotation.Configuration; import org.springframework.messaging.simp.config.ChannelRegistration; import org.springframework.messaging.simp.config.MessageBrokerRegistry; import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker; import org.springframework.web.socket.config.annotation.StompEndpointRegistry; import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer; /** * WebSocket相关配置 * * @author zifangsky * @date 2018/9/30 * @since 1.0.0 */ @Configuration @EnableWebSocketMessageBroker public class WebSocketConfig implements WebSocketMessageBrokerConfigurer{ @Autowired private AuthHandshakeInterceptor authHandshakeInterceptor; @Autowired private MyHandshakeHandler myHandshakeHandler; @Autowired private MyChannelInterceptor myChannelInterceptor; @Override public void registerStompEndpoints(StompEndpointRegistry registry) { registry.addEndpoint("/chat-websocket") .addInterceptors(authHandshakeInterceptor) .setHandshakeHandler(myHandshakeHandler) .withSockJS(); } @Override public void configureMessageBroker(MessageBrokerRegistry registry) { //客户端需要把消息发送到/message/xxx地址 registry.setApplicationDestinationPrefixes("/message"); //服务端广播消息的路径前缀,客户端需要相应订阅/topic/yyy这个地址的消息 registry.enableSimpleBroker("/topic"); //给指定用户发送消息的路径前缀,默认值是/user/ registry.setUserDestinationPrefix("/user/"); } @Override public void configureClientInboundChannel(ChannelRegistration registration) { registration.interceptors(myChannelInterceptor); } } 复制代码
(7)示例页面:
<html xmlns:th="http://www.thymeleaf.org"> <head> <meta content="text/html;charset=UTF-8"/> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> <meta http-equiv="X-UA-Compatible" content="IE=edge"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>Chat With STOMP Message</title> <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/sockjs-client/1.1.4/sockjs.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/stomp.js/2.3.3/stomp.min.js"></script> <script th:src="@{/layui/layui.js}"></script> <script th:src="@{/layui/lay/modules/layer.js}"></script> <link th:href="@{/layui/css/layui.css}" rel="stylesheet"> <link th:href="@{/layui/css/modules/layer/default/layer.css}" rel="stylesheet"> <link th:href="@{/css/style.css}" rel="stylesheet"> <style type="text/css"> #connect-container { margin: 0 auto; width: 400px; } #connect-container div { padding: 5px; margin: 0 7px 10px 0; } .message input { padding: 5px; margin: 0 7px 10px 0; } .layui-btn { display: inline-block; } </style> <script type="text/javascript"> var stompClient = null; $(function () { var target = $("#target"); if (window.location.protocol === 'http:') { target.val('http://' + window.location.host + target.val()); } else { target.val('https://' + window.location.host + target.val()); } }); function setConnected(connected) { var connect = $("#connect"); var disconnect = $("#disconnect"); var echo = $("#echo"); if (connected) { connect.addClass("layui-btn-disabled"); disconnect.removeClass("layui-btn-disabled"); echo.removeClass("layui-btn-disabled"); } else { connect.removeClass("layui-btn-disabled"); disconnect.addClass("layui-btn-disabled"); echo.addClass("layui-btn-disabled"); } connect.attr("disabled", connected); disconnect.attr("disabled", !connected); echo.attr("disabled", !connected); } //连接 function connect() { var target = $("#target").val(); var ws = new SockJS(target); stompClient = Stomp.over(ws); stompClient.connect({}, function () { setConnected(true); log('Info: STOMP connection opened.'); //连接成功后,主动拉取未读消息 pullUnreadMessage("/topic/reply"); //订阅服务端的/topic/reply地址 stompClient.subscribe("/user/topic/reply", function (response) { log(JSON.parse(response.body).content); }) },function () { //断开处理 setConnected(false); log('Info: STOMP connection closed.'); }); } //断开连接 function disconnect() { if (stompClient != null) { stompClient.disconnect(); stompClient = null; } setConnected(false); log('Info: STOMP connection closed.'); } //向指定用户发送消息 function sendMessage() { if (stompClient != null) { var receiver = $("#receiver").val(); var msg = $("#message").val(); log('Sent: ' + JSON.stringify({'receiver': receiver, 'msg':msg})); $.ajax({ url: "/wsTemplate/sendToUser", type: "POST", dataType: "json", async: true, data: { "receiver": receiver, "msg": msg }, success: function (data) { } }); } else { layer.msg('STOMP connection not established, please connect.', { offset: 'auto' ,icon: 2 }); } } //从服务器拉取未读消息 function pullUnreadMessage(destination) { $.ajax({ url: "/wsTemplate/pullUnreadMessage", type: "POST", dataType: "json", async: true, data: { "destination": destination }, success: function (data) { if (data.result != null) { $.each(data.result, function (i, item) { log(JSON.parse(item).content); }) } else if (data.code !=null && data.code == "500") { layer.msg(data.msg, { offset: 'auto' ,icon: 2 }); } } }); } //日志输出 function log(message) { console.debug(message); } </script> </head> <body> <noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websockets rely on Javascript being enabled. Please enable Javascript and reload this page!</h2></noscript> <div> <div id="connect-container" class="layui-elem-field"> <legend>Chat With STOMP Message</legend> <div> <input id="target" type="text" class="layui-input" size="40" style="width: 350px" value="/chat-websocket"/> </div> <div> <button id="connect" class="layui-btn layui-btn-normal" onclick="connect();">Connect</button> <button id="disconnect" class="layui-btn layui-btn-normal layui-btn-disabled" disabled="disabled" onclick="disconnect();">Disconnect </button> </div> <div class="message"> <input id="receiver" type="text" class="layui-input" size="40" style="width: 350px" placeholder="接收者姓名" value=""/> <input id="message" type="text" class="layui-input" size="40" style="width: 350px" placeholder="消息内容" value=""/> </div> <div> <button id="echo" class="layui-btn layui-btn-normal layui-btn-disabled" disabled="disabled" onclick="sendMessage();">Send Message </button> </div> </div> </div> </body> </html> 复制代码
测试效果省略,具体效果可以自行在两台不同服务器上面运行示例源码查看。
以上所述就是小编给大家介绍的《Spring Boot中使用WebSocket总结(三):使用消息队列实现分布式WebSocket》,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对 码农网 的支持!
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