webRTC（十），Android面试吃透这一篇就没有拿不到的offer

webRTC（十），Android面试吃透这一篇就没有拿不到的offer

Connect Sig Server

Leave

Local:

Remote:

js

‘use strict’

var localVideo = document.querySelector(‘video#localvideo’);

var remoteVideo = document.querySelector(‘video#remotevideo’);

var btnConn = document.querySelector(‘button#connserver’);

var btnLeave = document.querySelector(‘button#leave’);

var localStream = null;

var roomid = ‘111111’;

var socket =null;

var state = ‘init’;

var pc = null;

var pcConfig={

‘iceServers’:[{

‘urls’:‘turn:121.41.76.43:3478’,

‘credential’:‘123456’,

‘username’:‘huang’

}]

}

function sendMessage(roomid,data){

if(socket){

socket.emit(‘message’,roomid,data);

}

}

function getAnswer(desc){

pc.setLocalDescription(desc);

sendMessage(roomid,desc);

}

function handleAnswerError(err){

console.error(‘Failed to get Answer!’,err);

}

function getOffer(desc){

pc.setLocalDescription(desc);

sendMessage(roomid,desc)

}

function handleOfferError(err){

console.error(‘Failed to get Offer!’,err);

}

//接收远端流通道

function call(){

if(state === ‘joined_conn’){

if(pc){

var options = {

offerToReceiveAudio:1,

offerToReceiveVideo:1

}

pc.createOffer(options)

.then(getOffer)

.catch(handleOfferError);

}

}

}

// 第一步：开始服务

function connSignalServer(){

//开启本地视频

start();

return true;

}

function conn(){

//1 触发socke连接

socket = io.connect();

//2 加入房间后的回调

socket.on(‘joined’,(roomid,id)=>{

state = ‘joined’;

createPeerConnection();

btnConn.disabled = true;

btnLeave.disabled =false;

console.log(“reveive joined message:state=”,state);

});

socket.on(‘otherjoin’,(roomid,id)=>{

if (state === ‘joined_unbind’) {

createPeerConnection();

}

state = ‘joined_conn’;

//媒体协商

call();

console.log(“reveive otherjoin message:state=”,state);

});

socket.on(‘full’,(roomid,id)=>{

console.log('receive full message ', roomid, id);

closePeerConnection();

closeLocalMedia();

state = ‘leaved’;

btnConn.disabled = false;

btnLeave.disabled = true;

console.log(“reveive full message:state=”,state);

alert(“the room is full!”);

});

socket.on(‘leaved’,(roomid,id)=>{

state = ‘leaved’;

socket.disconnect();

btnConn.disabled = false;

btnLeave.disabled = true;

console.log(“reveive leaved message:state=”,state);

});

socket.on(‘bye’,(roomid,id)=>{

state = ‘joined_unbind’;

closePeerConnection();

console.log(“reveive bye message:state=”,state);

});

socket.on(‘disconnect’, (socket) => {

console.log(‘receive disconnect message!’, roomid);

if(!(state === ‘leaved’)){

closePeerConnection();

closeLocalMedia();

}

state = ‘leaved’;

});

socket.on(‘message’,(roomid,id,data)=>{

//媒体协商

if(data){

if(data.type === ‘offer’){

pc.setRemoteDescription(new RTCSessionDescription(data));

pc.createAnswer()

.then(getAnswer)

.catch(handleAnswerError);

}else if(data.type === ‘answer’){

console.log(“reveive client message=====>”,data);

pc.setRemoteDescription(new RTCSessionDescription(data));

}else if(data.type === ‘candidate’){

var candidate = new RTCIceCandidate({

sdpMLineIndex:data.label,

candidate:data.candidate

});

pc.addIceCandidate(candidate);

}else{

console.error(‘the message is invalid!’,data)

}

}

console.log(“reveive client message”,roomid,id,data);

});

socket.emit(‘join’,roomid);

return;

}

// 扑捉本地视频

function getMediaStream(stream){

localStream =stream;

//2 =显示本地视频=

localVideo.srcObject = localStream;

//这个函数的调用时机特别重要 一定要在getMediaStream之后再调用，否则会出现绑定失败的情况

conn();

}

function handleError(err){

if(err){

console.error(“getUserMedia error:”,err);

}

}

// 第二步：采集本地视频

function start(){

if (!navigator.mediaDevices||

!navigator.mediaDevices.getUserMedia) {

console.log(“getUserMedia is not supported!”)

return;

} else {

//1 =配置音视频参数=

var constraints={

video:true,

audio: true

}

navigator.mediaDevices.getUserMedia(constraints)

.then(getMediaStream)

.catch(handleError)

}

}

//关闭流通道

function closeLocalMedia(){

if (localStream&&localStream.getTracks()) {

localStream.getTracks().forEach((track)=>{

track.stop();

});

}

localStream = null;

}

function leave(){

if(socket){

socket.emit(‘leave’,roomid);

}

//释放资源

closePeerConnection();

closeLocalMedia();

btnConn.disabled = false;

btnLeave.disabled = true;

}

//创建本地流媒体链接

function createPeerConnection(){

console.log(‘create RTCPeerConnection!’);

if(!pc){

pc = new RTCPeerConnection(pcConfig);

pc.onicecandidate = (e) =>{

if(e.candidate){

sendMessage(roomid,{

type:‘candidate’,

label:e.candidate.sdpMLineIndex,

id:e.candidate.sdpMid,

candidate:e.candidate.candidate

});

}

}

pc.ontrack = (e)=>{

remoteVideo.srcObject = e.streams[0];

}

}

if(pc === null || pc === undefined){

console.error(‘pc is null or undefined!’);

return;

}

if(localStream === null || localStream === undefined){

console.error(‘localStream is null or undefined!’);

return;

}

if(localStream){

localStream.getTracks().forEach((track)=>{

pc.addTrack(track,localStream);

})

}

}

//关闭本地媒体流链接

function closePeerConnection(){

console.log(‘close RTCPeerConnection!’);

if(pc){

pc.close();

pc = null;

}

}

btnConn.onclick = connSignalServer;

btnLeave.onclick = leave;

服务器源码

‘use strict’

var http = require(‘http’);

var https = require(‘https’);

var fs = require(‘fs’);

var express= require(‘express’);

var serveIndex=require(‘serve-index’);

var USERCOUNT=3;

//命令服务器

var socketIo =require(‘socket.io’);

var log4js = require(‘log4js’);

log4js.configure({

appenders:{

file:{

type:‘file’,

filename:‘app.log’,

layout:{

type:‘pattern’,

pattern:’%r %p - %m’,

}

}

},

categories:{

default:{

appenders:[‘file’],

level:‘debug’

}

}

});

var logger = log4js.getLogger();

var app=express();

app.use(serveIndex(’./public’));

app.use(express.static(’./public’));

//http server

var http_server=http.createServer(app);

//-----------------------------------------------------------------------//

var options={

key:fs.readFileSync(’./cert/3435783_huangxiaoguo.club.key’),

cert:fs.readFileSync(’./cert/3435783_huangxiaoguo.club.pem’)

}

//https server

var https_server=https.createServer(options,app);

//命令服务器绑定https

var io = socketIo.listen(https_server);

io.sockets.on(‘connection’,(socket)=>{

logger.debug(“connection”);

//转发信息

socket.on(‘message’, (room, data)=>{

logger.debug("message data “+socket.id+” "+room,data);

socket.to(room).emit(‘message’, room, socket.id, data)//房间内所有人,除自己外

});

//用户加入

socket.on(‘join’,(room)=>{

logger.debug(“join”,",room = “, room,”,socket.id = ", socket.id);

socket.join(room);

var myRoom = io.sockets.adapter.rooms[room];

var users =(myRoom)?Object.keys(myRoom.sockets).length:0;

logger.debug(‘the number of user in room is:’+users)

//处理一对一通信

if (users

//给本人回信息

socket.emit(‘joined’,room,socket.id);

if(
users>1){

socket.to(room).emit(‘otherjoin’,room,socket.id);

}

}else{

socket.leave(room);

socket.emit(‘full’,room,socket.id);

}

//给本人回信息

//socket.emit(‘joined’,room,socket.id);

//给房间除自己以外所有人回
.on(‘message’, (room, data)=>{

logger.debug("message data “+socket.id+” "+room,data);

socket.to(room).emit(‘message’, room, socket.id, data)//房间内所有人,除自己外

});

//用户加入

socket.on(‘join’,(room)=>{

logger.debug(“join”,",room = “, room,”,socket.id = ", socket.id);

socket.join(room);

var myRoom = io.sockets.adapter.rooms[room];

var users =(myRoom)?Object.keys(myRoom.sockets).length:0;

logger.debug(‘the number of user in room is:’+users)

//处理一对一通信

if (users

//给本人回信息

socket.emit(‘joined’,room,socket.id);

if([外链图片转存中…(img-FYU9zQwE-1642841017498)]
users>1){

socket.to(room).emit(‘otherjoin’,room,socket.id);

}

}else{

socket.leave(room);

socket.emit(‘full’,room,socket.id);

}

//给本人回信息

//socket.emit(‘joined’,room,socket.id);

//给房间除自己以外所有人回