webRtc视频通话（jquery，node）

落日映苍穹つ 2022-12-13 14:18 240阅读 0赞

### 程序 ###

nodejs，jquery

### 定义 ###

WebRTC(Web Real-Time Communication) 网页即时通信 ，是一个支持网页浏览器进行实时语音、视频对话的API。  
于2011年6月1日开源并在Google、Mozilla、Opera支持下被纳入万维网联盟的W3C推荐标准

### 核心API ###

1.  getUserMedia：可以获取本地的媒体流，一个流包含几个轨道，比如视频和音频轨道。
2.  RTCPeerConnection：用于建立 P2P 连接以及传输多媒体数据。
3.  RTCDataChannel：建立一个双向通信的数据通道，可以传递多种数据类型。

### 获取本地媒体流 ###

通过 **getUserMedia** 函数，我们可以发起获取本地媒体流的请求：

navigator.getUserMedia(constraints, successCallback, errorCallback);

函数有三个参数，分别是约束条件，成功的回调和失败的回调。成功获取媒体流后，媒体流可以提供给本地的音频或视频元素进行播放、后期处理的 JavaScript 代理，或者发送给另一端。

### 前端 ###

<!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        <div class="page-container">
            <div class="message-box">
                <div class="message-list"></div>
                <div class="send-box">
                    <textarea class="send-content"></textarea>
                    <button class="sendbtn">发送</button>
                </div>
            </div>
            <div class="user-box">
                <video id="local-video" autoplay class="local-video"></video>
                <video id="remote-video" autoplay class="remote-video"></video>
                <p class="title">在线用户</p>
                <ul class="user-list"></ul>
            </div>
            <div class="mask">
                <div class="mask-content">
                    <input class="myname" type="text" placeholder="输入用户名加入房间">
                    <button class="add-room">加入</button>
                </div>
            </div>
            <div class="video-box">
    
            </div>
        </div>
        <script src="https://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"></script>
        <script src="https://cdn.bootcss.com/socket.io/2.1.1/socket.io.js"></script>
        <script>
            class Chat{ 
                constructor({  calledHandle, host, socketPath, getCallReject } = { }) { 
                    this.host = host;
                    this.socketPath = socketPath;
                    this.socket = null;
                    this.calledHandle =calledHandle;
                    this.getCallReject = getCallReject;
                    this.peer = null
                    this.localMedia = null
                }
                async init(){ 
                    this.socket = await this.connentSocket();
                    return this;
                }
                async connentSocket(){ 
                    if(this.socket){ 
                        return this.socket;
                    }
                    return new Promise((resolve, reject) => { 
                        let socket = io(this.host,{ 
                            path: this.socketPath
                        })
                        socket.on('connect', () => { 
                            console.log('连接成功');
                            resolve(socket);
                        })
                        socket.on('connect_error', e => { 
                            console.log('连接失败');
                            throw e;
                            reject()
                        })
    
                        /* * @desc 呼叫被接受 * @example * setRemoteDescription方法，改变与连接相关的远端描述。这个描述定义了连接的属性，例如：连接的编码方式。 * 连接会受到它的改变的影响，而且连接必须能同时支持新的以及旧的描述。 * 这个方法可以接收三个参数，一个RTCSessionDescription 对象包含设置信息， * 还有两个回调函数，它们分别是方法调用成功以及失败的回调函数。 * */
                        socket.on('answer', ({ answer}) => { 
                            this.peer && this.peer.setRemoteDescription(answer);
                        })
    
                        /* * @desc 被呼叫 * */
                        socket.on('called', (callingInfo) => { 
                            this.called && this.called(callingInfo);
                        })
    
                        /* * @desc 呼叫被拒绝 * */
                        socket.on('callRejected', () => { 
                            this.getCallReject && this.getCallReject()
                        })
    
                        socket.on('iceCandidate', ({  iceCandidate }) => { 
                            this.peer && this.peer.addIceCandidate(new RTCIceCandidate(iceCandidate))
                        })
                    })
                }
    
                addEvent(name, cb) { 
                    if (!this.socket) return
                    this.socket.on(name, data => { 
                        cb.call(this, data)
                    })
                }
    
                sendMessage(name, data) { 
                    if (!this.socket) return
                    this.socket.emit(name, data)
                }
    
                /* * @desc 获取本地媒体流 * */
                async getLocalMedia(){ 
                    let localMedia = await navigator.mediaDevices
                        .getUserMedia({  video: {  facingMode: "user" }, audio: true })
                        .catch(e => { 
                            console.log(e)
                        })
                    this.localMedia = localMedia;
                    return this;
                }
    
                /* * @desc 设置媒体流到video * */
                setMediaTo(eleId, media) { 
                    document.getElementById(eleId).srcObject = media;
                }
    
                /* * @dsec 被叫响应 * */
                called(callingInfo){ 
                    this.calledHandle && this.calledHandle(callingInfo);
                }
    
                /* * @desc 创建RTC * */
                createLoacalPeer(){ 
                    var PeerConnection = window.mozRTCPeerConnection || window.webkitRTCPeerConnection || window.RTCPeerConnection;
                    this.peer = new PeerConnection()
                    return this;
                }
    
                /* * @desc 将媒体流加入通信 * */
                addTrack(){ 
                    if (!this.peer || !this.localMedia) return
                    this.peer.addStream(this.localMedia);
                    return this;
                }
    
                /* * @desc 创建 SDP offer * */
                async createOffer(cb) { 
                    if (!this.peer) return
                    let offer = await this.peer.createOffer({  offerToReceiveAudio: true, offerToReceiveVideo: true })
                    this.peer.setLocalDescription(offer)
                    cb && cb(offer)
                    return this
                }
                async createAnswer(offer, cb) { 
                    if (!this.peer) return
                    this.peer.setRemoteDescription(offer)
                    let answer = await this.peer.createAnswer({  offerToReceiveAudio: true, offerToReceiveVideo: true })
                    this.peer.setLocalDescription(answer)
                    cb && cb(answer)
                    return this
    
                }
    
                listenerAddStream(cb){ 
                    this.peer.addEventListener('addstream', event => { 
                        console.log('addstream事件触发', event.stream);
                        cb && cb(event.stream);
                    })
                    return this;
                }
    
                /* * @desc 监听候选加入 * */
                listenerCandidateAdd(cb) { 
                    this.peer.addEventListener('icecandidate', event => { 
                        let iceCandidate = event.candidate;
                        if (iceCandidate) { 
                            console.log('发送candidate给远端');
                            cb && cb(iceCandidate);
                        }
    
                    })
                    return this
                }
    
                // 检测ice协商过程
                listenerGatheringstatechange  () { 
                    return this;
                }
    
                // 关闭RTC
                closeRTC() { 
                    // ....
                }
            }
        </script>
        <script>
            $(function () { 
                let chat = new Chat({ 
                    host: 'http://127.0.0.1:3003',
                    socketPath:'/websocket',
                    calledHandle: calledHandle,
                    getCallReject: getCallReject
                })
    
                // 更新视图
                function updateUserList(list) { 
                    $(".user-list").html(list.reduce((temp, li) => { 
                        temp += `<li class="user-li">${ li.name}<button data-calling=${ li.calling} data-id=${ li.id} class=${ li.id === this.socket.id || li.calling ? 'cannot-call' : 'can-call'}>通话</button></li>`
                        return temp
                    }, ''))
                }
    
                // 更新消息li表视图
                function updateMessageList(msg) { 
                    $('.message-list').append(`<li class=${ msg.userId === this.socket.id ? 'left' : 'right'}>${ msg.user}: ${ msg.content}</li>`)
                }
    
                // 加入房间
                $('.add-room').on('click', async () => { 
                    let name = $('.myname').val();
                    if(!name){ 
                        return;
                    }
                    $('.mask').fadeOut();
                    await chat.init();
                    chat.addEvent('updateUserList', updateUserList);
                    chat.addEvent('updateMessageList', updateMessageList);
                    chat.sendMessage('addUser', { name})
                })
    
                // 发送消息
                $('.sendbtn').on('click', () => { 
                    let sendContent = $('.send-content').val()
                    if (!sendContent) return
                    $('.send-content').val('')
                    chat.sendMessage('sendMessage', {  content: sendContent })
                })
    
                // 视频
                $('.user-list').on('click', '.can-call', async function () { 
                    // 被叫方信息
                    let calledParty = $(this).data();
                    if(calledParty.calling){ 
                        alert('对方正在通话中');
                        return;
                    }
                    // 初始本地视频
                    $('.local-video').fadeIn();
                    await chat.getLocalMedia();
                    chat.setMediaTo('local-video', chat.localMedia);
                    chat.createLoacalPeer().listenerGatheringstatechange().addTrack().listenerAddStream(stream => { 
                        $('.remote-video').fadeIn();
                        chat.setMediaTo('remote-video', stream);
                    }).listenerCandidateAdd(iceCandidate => { 
                        chat.sendMessage('iceCandidate', {  iceCandidate, id: calledParty.id })
                    }).createOffer(offer => { 
                        chat.sendMessage('offer', {  offer, ...calledParty })
                    })
                })
    
                //呼叫被拒绝
                function getCallReject() { 
                    chat.closeRTC()
                    $('.local-video').fadeIn()
                    console.log('呼叫被拒');
                }
    
                // 被叫
                async function calledHandle(callingInfo) { 
                    if (!confirm(`是否接受${ callingInfo.name}的视频通话`)) { 
                        chat.sendMessage('rejectCall', callingInfo.id)
                        return
                    }
    
                    $('.local-video').fadeIn()
                    await chat.getLocalMedia()
                    chat.setMediaTo('local-video', chat.localMedia)
    
                    chat.createLoacalPeer()
                        .listenerGatheringstatechange()
                        .addTrack()
                        .listenerCandidateAdd(function (iceCandidate) { 
    
                            chat.sendMessage('iceCandidate', {  iceCandidate, id: callingInfo.id })
    
                        })
                        .listenerAddStream(function (stream) { 
    
                            $('.remote-video').fadeIn()
                            chat.setMediaTo('remote-video', stream)
    
                        })
                        .createAnswer(callingInfo.offer, function (answer) { 
    
                            chat.sendMessage('answer', {  answer, id: callingInfo.id })
    
                        })
    
    
                }
            })
        </script>
    </body>
    </html>

### node端 ###

*  server.js

const SocketIO = require('socket.io')
    const socketIO = new SocketIO({ 
        path: '/websocket'
    })
    
    let userRoom = { 
        list: [],
        add(user) { 
            this.list.push(user)
            return this
        },
        del(id) { 
            this.list = this.list.filter(u => u.id !== id)
            return this
        },
        sendAllUser(name, data) { 
            this.list.forEach(({  id }) => { 
                console.log('>>>>>', id)
                socketIO.to(id).emit(name, data)
            })
            return this
        },
        sendTo(id) { 
            return (eventName, data) => { 
                socketIO.to(id).emit(eventName, data)
            }
        },
        findName(id) { 
            return this.list.find(u => u.id === id).name
        }
    }
    
    socketIO.on('connection', function(socket) { 
        console.log('连接加入.', socket.id)
    
        socket.on('addUser', function(data) { 
            console.log(data.name, '加入房间')
            let user = { 
                id: socket.id,
                name: data.name,
                calling: false
            }
            userRoom.add(user).sendAllUser('updateUserList', userRoom.list)
        })
    
        socket.on('sendMessage', ({  content }) => { 
            console.log('转发消息：', content)
            userRoom.sendAllUser('updateMessageList', {  userId: socket.id, content, user: userRoom.findName(socket.id) })
        })
    
        socket.on('iceCandidate', ({  id, iceCandidate }) => { 
            console.log('转发信道')
            userRoom.sendTo(id)('iceCandidate', {  iceCandidate, id: socket.id })
        })
    
        socket.on('offer', ({ id, offer}) => { 
            console.log('转发offer')
            userRoom.sendTo(id)('called', {  offer, id: socket.id, name: userRoom.findName(socket.id)})
        })
    
        socket.on('answer', ({ id, answer}) => { 
            console.log('接受视频');
            userRoom.sendTo(id)('answer', { answer})
        })
    
        socket.on('rejectCall', id => { 
            console.log('转发拒接视频')
            userRoom.sendTo(id)('callRejected')
        })
    
        socket.on('disconnect', () => { 
            // 断开删除
            console.log('连接断开', socket.id)
            userRoom.del(socket.id).sendAllUser('updateUserList', userRoom.list)
        })
    })
    
    module.exports = socketIO

*  www.js

// www.js 这就不关键了
    const http = require('http')
    const socketIO = require('./server.js')
    const server = http.createServer()
    socketIO.attach(server)
    server.listen(3003, () => { 
        console.log('server start on 127.0.0.1:3003')
    })

### 启动 ###

node www.js  
火狐浏览器打开html