WebRTC连通性问题

Question

最近我一直在用WebRTC做实验。我试着把我的头绕在它周围，同时看看我是否能测试它。

所以我写了一个测试来检查两件事

1. 联系是否一致？
2. 节点的数量会减缓连接的速度吗?如果是的话，那么在它变得明显之前，阈值是多少？

我在考试中注意到的是，(1)不是真的。我所发现的是，这个测试的平均结果是100次中的10到20次？

我要求的是有人看一看，让我知道我是否写错了我的测试，或者也许找出了失败的另一个原因。

请注意，我只在Chrome 62上运行这个程序，冰服务器列表是从https://github.com/DamonOehlman/freeice获取的。

下面是我写的一个测试：

const localStream = await navigator.mediaDevices.getUserMedia({video:true});
const iceServers = [{
    urls: [
        "stun:stun.l.google.com:19302",
        "stun:stun1.l.google.com:19302",
        "stun:stun2.l.google.com:19302",
        "stun:stun3.l.google.com:19302",
        "stun:stun4.l.google.com:19302",
        "stun:stun.ekiga.net",
        "stun:stun.ideasip.com",
        "stun:stun.rixtelecom.se",
        "stun:stun.schlund.de",
        "stun:stun.stunprotocol.org:3478",
        "stun:stun.voiparound.com",
        "stun:stun.voipbuster.com",
        "stun:stun.voipstunt.com",
        "stun:stun.voxgratia.org"
    ]
}]

async function initExample(){
    try{
        // Init Local Connections
        var localConnection = new RTCPeerConnection({iceServers});
        var remoteConnection = new RTCPeerConnection({iceServers});

        // Create Data Channels
        var remoteDataChannel;// this is added later
        var localDataChannel = localConnection.createDataChannel('DataChannel');

        // Configure Stream
        var remoteStream;// this is added later
        localConnection.addStream(localStream)

        // Catch DataChannel when it is sent from local to remote
        remoteConnection.ondatachannel = dataChannelEvent => {
            remoteDataChannel = dataChannelEvent.channel
        }

        // Catch MediaStream when it is sent from local to remote
        remoteConnection.onaddstream = mediaStreamEvent => {
            remoteStream = mediaStreamEvent.stream;
        }

        // Create Offer
        var offer = await localConnection.createOffer();
        await localConnection.setLocalDescription(offer);
        await remoteConnection.setRemoteDescription(localConnection.localDescription);

        // Create Answer
        var answer = await remoteConnection.createAnswer();
        await remoteConnection.setLocalDescription(answer);
        await localConnection.setRemoteDescription(remoteConnection.localDescription);

        // Return Results
        return {
            localConnection, remoteConnection,
            localDataChannel, localStream,
            get remoteDataChannel(){
                return remoteDataChannel
            },
            get remoteStream(){
                return remoteStream;
            },
        }
    }catch(e){
        console.error(e)
    }
}

async function test(N=100){
    const stats = {pass:0, fail: 0, N};
    const results = [];
    for (var i = 0; i < N; i++) {
        console.log({...stats, i})
        let conn = await initExample();
        if(conn.remoteDataChannel){
            stats.pass++;
        }else{
            stats.fail++;
        }
        results.push(conn);
    }
    return results;
}

var r = await test();

Answer 1

因此，在@JTejedor的评论和建议之后，我意识到我的连接测试设置错误。对于任何有此问题的人，请注意，您需要确保同侪正在发送他们的注册冰候选人到对方。

在我的脱机版本中，这样做如下：

// Map Ice Candidate
remoteConnection.onicecandidate = evt => {
    if(evt.candidate) {
        localConnection.addIceCandidate(evt.candidate)
    }
}
localConnection.onicecandidate = evt => {
    if(evt.candidate) {
        remoteConnection.addIceCandidate(evt.candidate)
    }
}

如果使用套接字(或其他服务器端解决方案)，请确保通过套接字将这些套接字发送给其他对等方。

下面是工作测试(总是通过)：

// Ice Servers
const iceServers = [{
    urls: [
        "stun:stun.l.google.com:19302",
        "stun:stun1.l.google.com:19302",
        "stun:stun2.l.google.com:19302",
        "stun:stun3.l.google.com:19302",
        "stun:stun4.l.google.com:19302",
        "stun:stun.ekiga.net",
        "stun:stun.ideasip.com",
        "stun:stun.rixtelecom.se",
        "stun:stun.schlund.de",
        "stun:stun.stunprotocol.org:3478",
        "stun:stun.voiparound.com",
        "stun:stun.voipbuster.com",
        "stun:stun.voipstunt.com",
        "stun:stun.voxgratia.org"
    ]
}]

// Run the test once
async function initExample(){
    // Init Local Connections
    var localConnection = new RTCPeerConnection({iceServers});
    var remoteConnection = new RTCPeerConnection({iceServers});//this is really "remote" its simulated

    // Map Ice Candidate
    remoteConnection.onicecandidate = evt => {
        if(evt.candidate) {
            localConnection.addIceCandidate(evt.candidate)
        }
    }
    localConnection.onicecandidate = evt => {
        if(evt.candidate) {
            remoteConnection.addIceCandidate(evt.candidate)
        }
    }

    // Create Data Channels
    var remoteDataChannel;// this is added later
    var localDataChannel = localConnection.createDataChannel('DataChannel');

    // Tie end of promise to getting the datachannel
    return new Promise( async res => {
        // Catch DataChannel when it is sent from local to remote
        remoteConnection.ondatachannel = dataChannelEvent => {
            console.log('GOT CHANNEL', dataChannelEvent)
            remoteDataChannel = dataChannelEvent.channel
            res(remoteDataChannel);
        }

        // Create Offer
        var offer = await localConnection.createOffer();
        await localConnection.setLocalDescription(offer);
        await remoteConnection.setRemoteDescription(localConnection.localDescription);

        // Create Answer
        var answer = await remoteConnection.createAnswer();
        await remoteConnection.setLocalDescription(answer);
        await localConnection.setRemoteDescription(remoteConnection.localDescription);

    })
}

// A Promisified Timeout
const promisedTimeout = (timeout = 10000) => new Promise((resolve, reject) => {
  let wait = window.setTimeout(() => {
    window.clearTimeout(wait);
    resolve(false);
  }, timeout)
})

// Run the test N times
async function test(N=100){
    // Init variables
    const stats = {pass:0, fail: 0, N};
    const results = [];

    // Loop
    for (var i = 0; i <= N; i++) {
        // log
        console.log({...stats, i});

        // This will each example against a timeout, 
        // if the timeout finishes first, then this test will be marked as fail
        let pass = await Promise.race([
            initExample(),
            promisedTimeout()
        ]);
        if(pass) {
            stats.pass ++;
        }else{
            stats.fail ++;
        }
        results.push(pass);
    }
    return {results,stats};
}

// Run the test
test()