引言
自己写了个小项目游戏报价器，想在更新系统的时候可以提前在系统弹窗提示用户，注意系统更新。
第一想到的就是WebSocket了，在更新前，提前发布公告，通过WebSocket推送到web客户端界面。
WebSocket是一种通信协议，可在单个TCP连接上进行全双工通信。WebSocket使得客户端和服务器之间的数据交换变得更加简单，允许服务端主动向客户端推送数据。在WebSocket API中，浏览器和服务器只需要完成一次握手，两者之间就可以建立持久性的连接，并进行双向数据传输。
具体实现方法如下：
添加依赖
版本自定，我用的最新版。
<!-- SpringBoot Websocket --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> <version>2.2.13.RELEASE</version> </dependency>
取消Websocket鉴权认证
如果你没有用到若依，并且接口访问没有鉴权仅仅是测试使用，可以跳过这一步。
如果你用的是若依的前后分离版 需要到spring security配置中修改，具体文件位置为framework模块-config-SecurityConfig.java-configure方法。
添加如下代码：
.antMatchers("/websocket/**").anonymous()
- 如果你是若依前后不分离版本应该用的是Shiro，需要在ShiroConfig.java中操作。
在对应取消鉴权认证的位置添加如下代码：
filterChainDefinitionMap.put("/websocket/**", "anon");
添加配置
我是在framework模块新建了一个websocket包。
包内的代码如下：
package com.rdjxx.framework.websocket; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.web.socket.server.standard.ServerEndpointExporter; /** * websocket 配置 * * @author fm */ @Configuration public class WebSocketConfig { @Bean public ServerEndpointExporter serverEndpointExporter() { return new ServerEndpointExporter(); } }
package com.rdjxx.framework.websocket; import java.util.concurrent.Semaphore; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * 信号量相关处理 * * @author fm */ public class SemaphoreUtils { /** * SemaphoreUtils 日志控制器 */ private static final Logger LOGGER = LoggerFactory.getLogger(SemaphoreUtils.class); /** * 获取信号量 * * @param semaphore * @return */ public static boolean tryAcquire(Semaphore semaphore) { boolean flag = false; try { flag = semaphore.tryAcquire(); } catch (Exception e) { LOGGER.error("获取信号量异常", e); } return flag; } /** * 释放信号量 * * @param semaphore */ public static void release(Semaphore semaphore) { try { semaphore.release(); } catch (Exception e) { LOGGER.error("释放信号量异常", e); } } }
package com.rdjxx.framework.websocket; import java.util.List; import java.util.concurrent.Semaphore; import javax.websocket.OnClose; import javax.websocket.OnError; import javax.websocket.OnMessage; import javax.websocket.OnOpen; import javax.websocket.Session; import javax.websocket.server.ServerEndpoint; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Component; /** * websocket 消息处理 * * @author fm */ @Component @ServerEndpoint("/websocket/message") public class WebSocketServer { /** * WebSocketServer 日志控制器 */ private static final Logger LOGGER = LoggerFactory.getLogger(WebSocketServer.class); /** * 默认最多允许同时在线人数100 */ public static int socketMaxOnlineCount = 1000; private static Semaphore socketSemaphore = new Semaphore(socketMaxOnlineCount); /** * 连接建立成功调用的方法 */ @OnOpen public void onOpen(Session session) throws Exception { boolean semaphoreFlag = false; // 尝试获取信号量 semaphoreFlag = SemaphoreUtils.tryAcquire(socketSemaphore); if (!semaphoreFlag) { // 未获取到信号量 LOGGER.error("\n 当前在线人数超过限制数- {}", socketMaxOnlineCount); // WebSocketUsers.sendMessageToUserByText(session, "当前在线人数超过限制数：" + socketMaxOnlineCount); session.close(); } else { // 添加用户 WebSocketUsers.put(session.getId(), session); //LOGGER.info("\n 建立连接 - {}", session); //LOGGER.info("\n 当前人数 - {}", WebSocketUsers.getUsers().size()); // WebSocketUsers.sendMessageToUserByText(session, "连接成功"); } } /** * 连接关闭时处理 */ @OnClose public void onClose(Session session) { //LOGGER.info("\n 关闭连接 - {}", session); // 移除用户 WebSocketUsers.remove(session.getId()); // 获取到信号量则需释放 SemaphoreUtils.release(socketSemaphore); } /** * 抛出异常时处理 */ @OnError public void onError(Session session, Throwable exception) throws Exception { if (session.isOpen()) { // 关闭连接 session.close(); } String sessionId = session.getId(); //LOGGER.info("\n 连接异常 - {}", sessionId); //LOGGER.info("\n 异常信息 - {}", exception); // 移出用户 WebSocketUsers.remove(sessionId); // 获取到信号量则需释放 SemaphoreUtils.release(socketSemaphore); } /** * 服务器接收到客户端消息时调用的方法 */ @OnMessage public void onMessage(String message, Session session) { String msg = message.replace("你", "我").replace("吗", ""); WebSocketUsers.sendMessageToUserByText(session, msg); } }
package com.rdjxx.framework.websocket; import java.io.IOException; import java.util.Collection; import java.util.Map; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import javax.websocket.Session; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * websocket 客户端用户集 * * @author fm */ public class WebSocketUsers { /** * WebSocketUsers 日志控制器 */ private static final Logger LOGGER = LoggerFactory.getLogger(WebSocketUsers.class); /** * 用户集 */ private static Map<String, Session> USERS = new ConcurrentHashMap<String, Session>(); /** * 存储用户 * * @param key 唯一键 * @param session 用户信息 */ public static void put(String key, Session session) { USERS.put(key, session); } /** * 移除用户 * * @param session 用户信息 * * @return 移除结果 */ public static boolean remove(Session session) { String key = null; boolean flag = USERS.containsValue(session); if (flag) { Set<Map.Entry<String, Session>> entries = USERS.entrySet(); for (Map.Entry<String, Session> entry : entries) { Session value = entry.getValue(); if (value.equals(session)) { key = entry.getKey(); break; } } } else { return true; } return remove(key); } /** * 移出用户 * * @param key 键 */ public static boolean remove(String key) { //LOGGER.info("\n 正在移出用户 - {}", key); Session remove = USERS.remove(key); if (remove != null) { boolean containsValue = USERS.containsValue(remove); //LOGGER.info("\n 移出结果 - {}", containsValue ? "失败" : "成功"); return containsValue; } else { return true; } } /** * 获取在线用户列表 * * @return 返回用户集合 */ public static Map<String, Session> getUsers() { return USERS; } /** * 群发消息文本消息 * * @param message 消息内容 */ public static void sendMessageToUsersByText(String message) { Collection<Session> values = USERS.values(); for (Session value : values) { sendMessageToUserByText(value, message); } } /** * 发送文本消息 * */ public static void sendMessageToUserByText(Session session, String message) { if (session != null) { try { session.getBasicRemote().sendText(message); } catch (IOException e) { LOGGER.error("\n[发送消息异常]", e); } } else { //LOGGER.info("\n[你已离线]"); } } }
前端
<template> <div class="navbar"> <hamburger id="hamburger-container" :is-active="sidebar.opened" class="hamburger-container" @toggleClick="toggleSideBar"/> <breadcrumb id="breadcrumb-container" class="breadcrumb-container" v-if="!topNav"/> <top-nav id="topmenu-container" class="topmenu-container" v-if="topNav"/> <div class="right-menu"> <template v-if="device!=='mobile'"> <screenfull id="screenfull" class="right-menu-item hover-effect"/> <el-tooltip content="布局大小" effect="dark" placement="bottom"> <size-select id="size-select" class="right-menu-item hover-effect"/> </el-tooltip> </template> <el-dropdown class="avatar-container right-menu-item hover-effect" trigger="click"> <div class="avatar-wrapper"> <img :src="avatar" class="user-avatar"> <i class="el-icon-caret-bottom"/> </div> <el-dropdown-menu slot="dropdown"> <router-link to="/user/profile"> <el-dropdown-item>个人中心</el-dropdown-item> </router-link> <el-dropdown-item @click.native="setting = true"> <span>布局设置</span> </el-dropdown-item> <el-dropdown-item divided @click.native="logout"> <span>退出登录</span> </el-dropdown-item> </el-dropdown-menu> </el-dropdown> </div> </div> </template> <script> import {mapGetters} from 'vuex' import Breadcrumb from '@/components/Breadcrumb' import TopNav from '@/components/TopNav' import Hamburger from '@/components/Hamburger' import Screenfull from '@/components/Screenfull' import SizeSelect from '@/components/SizeSelect' import Search from '@/components/HeaderSearch' import RuoYiGit from '@/components/RuoYi/Git' import RuoYiDoc from '@/components/RuoYi/Doc' import {Notification} from "element-ui"; import {getNoticeListTop3} from "@/api/system/navbar"; export default { data() { return { url: "ws://localhost:8087/websocket/message", message: "", text_content: "", ws: null, }; }, components: { Breadcrumb, TopNav, Hamburger, Screenfull, SizeSelect, Search, RuoYiGit, RuoYiDoc }, computed: { ...mapGetters([ 'sidebar', 'avatar', 'device' ]), setting: { get() { return this.$store.state.settings.showSettings }, set(val) { this.$store.dispatch('settings/changeSetting', { key: 'showSettings', value: val }) } }, topNav: { get() { return this.$store.state.settings.topNav } } }, mounted() { this.notice(); const wsuri = this.url; this.ws = new WebSocket(wsuri); const self = this; this.ws.onopen = function (event) { //self.text_content = self.text_content + "已经打开连接!" + "\n"; }; this.ws.onmessage = function (event) { //self.text_content = event.data + "\n"; var messageBody = JSON.parse(event.data); Notification.info({ title: "通知", dangerouslyUseHTMLString: true, message: messageBody.noticeContent, duration: 0, offset: 40, onClick: function () { //self.warnDetailByWarnid(messageBody.warnId); //自定义回调,message为传的参数 // 点击跳转的页面 }, }); }; this.ws.onclose = function (event) { //self.text_content = self.text_content + "已经关闭连接!" + "\n"; }; }, methods: { notice() { getNoticeListTop3().then(response => { for (let i = 0; i < response.length; i++) { let messageBody = response[i]; setTimeout(() => { this.notificationInfo(messageBody); }, 100); } }) }, notificationInfo(messageBody) { Notification.info({ title: "通知", dangerouslyUseHTMLString: true, message: messageBody.noticeContent, duration: 0, offset: 40, onClick: function () { //self.warnDetailByWarnid(messageBody.warnId); //自定义回调,message为传的参数 // 点击跳转的页面 }, }); }, // join() { // // }, exit() { if (this.ws) { this.ws.close(); this.ws = null; } }, send() { if (this.ws) { this.ws.send(this.message); } else { alert("未连接到服务器"); } }, warnDetailByWarnid(warnid) { // 跳转预警详情页面 this.$router.push({ path: "/XXX/XXX", query: { warnid: warnid, }, }); }, toggleSideBar() { this.$store.dispatch('app/toggleSideBar') }, async logout() { this.$confirm('确定注销并退出系统吗？', '提示', { confirmButtonText: '确定', cancelButtonText: '取消', type: 'warning' }).then(() => { this.$store.dispatch('LogOut').then(() => { location.href = '/index'; }) }).catch(() => { }); } } } </script> <style lang="scss" scoped> .navbar { height: 50px; overflow: hidden; position: relative; background: #fff; box-shadow: 0 1px 4px rgba(0, 21, 41, .08); .hamburger-container { line-height: 46px; height: 100%; float: left; cursor: pointer; transition: background .3s; -webkit-tap-highlight-color: transparent; &:hover { background: rgba(0, 0, 0, .025) } } .breadcrumb-container { float: left; } .topmenu-container { position: absolute; left: 50px; } .errLog-container { display: inline-block; vertical-align: top; } .right-menu { float: right; height: 100%; line-height: 50px; &:focus { outline: none; } .right-menu-item { display: inline-block; padding: 0 8px; height: 100%; font-size: 18px; color: #5a5e66; vertical-align: text-bottom; &.hover-effect { cursor: pointer; transition: background .3s; &:hover { background: rgba(0, 0, 0, .025) } } } .avatar-container { margin-right: 30px; .avatar-wrapper { margin-top: 5px; position: relative; .user-avatar { cursor: pointer; width: 40px; height: 40px; border-radius: 10px; } .el-icon-caret-bottom { cursor: pointer; position: absolute; right: -20px; top: 25px; font-size: 12px; } } } } } </style>
import request from '@/utils/request' // 获取前三个通知用于平时展示 export function getNoticeListTop3(query) { return request({ url: '/system/notice/listTop3/', method: 'get', params: query }) }
