🎨领域:Java后端开发
🔥收录专栏: 系统设计与实战 🐒个人主页:BreezAm 💖Gitee:https://gitee.com/BreezAm ?个人标签:【后端】【大数据】【前端】【运维】
🌿一、技术介绍
线上演示地址:http://chat.breez.work
实时通信 (Instant Messaging,简称IM)是一个实时 通信系统,允许两人或多人使用网络实时的传递文字消息 、文件 、语音 与视频交流 。[4]
场景再现:
🌳1.1 客户端WebSocket
WebSocket 对象提供了用于创建和管理 WebSocket 连接,以及可以通过该连接发送 和接收数据 的 API。使用 WebSocket() 构造函数来构造一个 WebSocket。[1]
构造函数如下所示:
const webSocket = WebSocket(url[, protocols])
例子如下:
const webSocket = new WebSocket("ws://42.193.120.86:3688/ws/小明/翠花")
🌴1.1.1 函数
1、 webSocket.send() 该函数用于向服务端发送一条消息,例子如下:
webSocket.send("Hello server!");
2、 webSocket.close() 该函数用于关闭客户端与服务端的连接,例子如下:
webSocket.close();
🌴1.1.2 事件
1、webSocket.onopen 该事件用于监听客户端与服务端的连接状态,如果客户端与服务端连接成功 则该事件触发,例子如下:
webSocket.onopen = function(event) {
console.log("连接已经建立,可以进行通信");
};
2、webSocket.onclose 如果服务端与客户端连接断开,那么此事件出发,例子如下:
webSocket.onclose = function(event) {
console.log("连接已经关闭");
};
3、webSocket: message event 该事件用于监听服务端向客户端发送的消息,例子如下:
webSocket.addEventListener('message', function (event) {
console.log('来自服务端的消息:', event.data);
});
4、webSocket:error event 如果客户端与服务端发生错误时,那么此事件将会触发,例子如下:
webSocket.addEventListener('error', function (event) {
console.log('连接出现错误', event);
});
🌳1.2 服务端WebSocket
@ServerEndpoint 用于声明一个socket服务,例子如下:
@ServerEndpoint(value = "/ws/{userId}/{targetId}")
几个重要的方法 注解:
@OnOpen 打开连接@OnClose 监听关闭@OnMessage 发送消息@OnError 监听错误
🌿二、实战
🌳2.1、服务端
🌴2.1.1引入maven依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
🌴2.1.2 编写配置类
@Configuration
public class WebSocketConfig {
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}
🌴2.1.3 编写WebSocketService服务类
下面的userId 代表发送者 的ID号,target 代表发送目标 ID号。
@Component
@ServerEndpoint(value = "/ws/{userId}/{target}")
public class WebSocketService {
private static ConcurrentHashMap<String, Session> SESSION = new ConcurrentHashMap<>();
private static AtomicInteger count = new AtomicInteger();
private Queue<String> queue = new LinkedBlockingDeque<>();
}
🌴2.1.4 建立连接
建立连接之前,判断用户是否已经连接,如果没有连接,那么将用户session信息保存到集合,然后计数器递增。
@OnOpen
public void onOpen(Session session, @PathParam("userId") String userId) {
if (!SESSION.containsKey(userId)) {
SESSION.put(userId, session);
count.incrementAndGet();
}
}
🌴2.1.5 关闭连接
关闭连接的时候,将用户session删除和计数器递减。
@OnClose
public void onClose(@PathParam("userId") String userId) {
SESSION.remove(userId);
count.decrementAndGet();
}
🌴2.1.6 发送消息
发送采用的方法是:session.getBasicRemote().sendText("你好");
@OnMessage
public void onMessage(String message, @PathParam("userId") String userId, @PathParam("target") String target) throws IOException {
queue.add(message);
Session s = SESSION.get(target);
if (s == null) {
Session b = SESSION.get(userId);
b.getBasicRemote().sendText("对方不在线");
} else {
for (int i = 0; i < queue.size(); i++) {
String msg = queue.poll();
Message m = new Message();
m.setUserId(userId);
s.getBasicRemote().sendText(msg);
}
}
}
🌴2.1.7 监听错误
出现错误,删除用户session信息和计数器递减
@OnError
public void onError(Throwable error, @PathParam("userId") String userId) {
SESSION.remove(userId);
count.decrementAndGet();
error.printStackTrace();
}
🌳2.2 客户端
本案例中客户端采用Nuxt编写,相关代码如下
🌴2.2.1 主页面
运行截图如图所示:
<template>
<div style="padding-left: 20%;">
<div style="padding-left: 20%;padding-top: 30px;">
<div style="font-size: 30px;">欢迎使用喵喵号聊天</div>
</div>
<div style="padding-top: 20%;">
<el-form :rules="rules" ref="formInline" :inline="true" :model="formInline" class="demo-form-inline">
<el-form-item label="我的喵喵号" prop="userId">
<el-input v-model="formInline.userId" placeholder="喵喵号"></el-input>
</el-form-item>
<el-form-item label="对方喵喵号" prop="targetId">
<el-input v-model="formInline.targetId" placeholder="喵喵号"></el-input>
</el-form-item>
<el-form-item>
<el-button type="primary" @click="onSubmit('formInline')">聊一下</el-button>
</el-form-item>
</el-form>
</div>
</div>
</template>
<script>
export default {
name: 'IndexPage',
data() {
return {
formInline: {
userId: '',
targetId: ''
},
rules: {
userId: [{
required: true,
message: '请输入你的喵喵号',
trigger: 'blur'
}],
targetId: [{
required: true,
message: '请输入对方喵喵号',
trigger: 'blur'
}]
}
}
},
methods: {
onSubmit(formName) {
this.$refs[formName].validate((valid) => {
if (valid) {
this.$router.push({
name: 'chat',
params: this.formInline
})
} else {
console.log('error submit!!');
return false;
}
});
}
},
created() {
}
}
</script>
<style>
body {
background: url('../static/img/cat.jpg');
}
</style>
🌴2.2.1 聊天页面
运行截图如下: 小明
翠花
<template>
<div>
<el-row :gutter="20" style="padding-top: 20px;">
<div style="padding-left: 35%;">
<div style="padding-bottom: 15px">
<div style="float: left;padding-right: 30px;">
我的喵喵号:<el-tag type="warning">{{user.userId}}</el-tag>
</div>
<div>
对方喵喵号:<el-tag type="success">{{user.targetId}}</el-tag>
<el-link @click="clearMsg()" :underline="false" style="padding-left: 30px;" type="danger">清空消息</el-link>
</div>
</div>
<div style="border: 1px green solid;width: 400px;height: 400px;border-radius: 10px;">
<div v-for="(m,index) in msgList" :key="index++">
<el-row :gutter="20">
<div v-if="m.type===1" style="padding-left: 10px;">
<el-avatar src="https://cube.elemecdn.com/0/88/03b0d39583f48206768a7534e55bcpng.png"></el-avatar>
{{m.msg}}
</div>
<div v-if="m.type===2" style="padding-right: 15px;float: right;">
{{m.msg}}
<el-avatar src="https://fuss10.elemecdn.com/e/5d/4a731a90594a4af544c0c25941171jpeg.jpeg"></el-avatar>
</div>
<div v-if="m.type===3" style="padding-left: 15px;padding-top: 15px;">系统消息:{{m.msg}}</div>
</el-row>
</div>
</div>
</div>
</el-row>
<el-row :gutter="5" style="padding-top: 20px;padding-left: 35%;">
<el-col :span="9" :xs="9" :sm="9" :md="9" :lg="9" :xl="9">
<el-input :disabled="msg_status" v-model="msg" placeholder="消息"></el-input>
</el-col>
<el-col :span="2">
<el-button @click="sendMessage()" type="primary">发送</el-button>
</el-col>
</el-row>
</div>
</template>
<script>
export default {
name: 'ChatPage',
data() {
return {
url: 'localhost:3688/ws/1001/1002',
msg: '',
socket: {},
msg_status: true,
msgList: [],
initList: [],
count: 0,
user: {
userId: '',
targetId: ''
}
}
},
created() {
const userId = this.$route.params.userId
const targetId = this.$route.params.targetId
if (userId !== undefined && targetId !== undefined) {
this.user.userId = userId
this.user.targetId = targetId
this.connect()
} else {
this.$router.push("/")
}
},
methods: {
connect() {
var that = this
this.socket = new WebSocket("ws://42.193.120.86:3688/ws/" + this.user.userId + "/" + this.user.targetId);
this.socket.onclose = function(event) {
that.$message('连接关闭');
};
this.socket.addEventListener('error', function(event) {
that.$message.error('出现错误');
});
this.socket.addEventListener('message', function(event) {
that.msgList.push({
type: 2,
msg: event.data
})
console.log(event.data);
console.log({
type: 2,
msg: event.data
});
});
this.socket.onopen = function(event) {
that.msg_status = false
that.msgList.push({
type: 3,
msg: '连接成功'
})
};
},
clearMsg() {
this.$confirm('确认清空?', '提示', {
confirmButtonText: '确定',
cancelButtonText: '取消',
type: 'warning'
}).then(() => {
this.msgList = []
})
},
sendMessage() {
this.socket.send(this.msg)
this.msgList.push({
type: 1,
msg: this.msg
})
this.msg = ''
}
}
}
</script>
<style>
</style>
🌿三、开源地址
🌿四、参考文献
🔥收录专栏:系统设计与实战
|