Question

我正在为peerconnection实现webrtc但是没有工作。当我调试这段代码然后我看到它没有进入

    theirConnection.onaddstream = function (e) {
        theirVideo.src = window.URL.createObjectURL(e.stream);
    };

块。请让我知道我做错了什么？我在本地系统上使用此功能，仅使用一个网络摄像头。

function startPeerConnection(stream) {

    var configuration = {
        "iceServers": [{ "url": "stun:127.0.0.1:8080" }]
    };

    yourConnection = new mozRTCPeerConnection(configuration);
    theirConnection = new mozRTCPeerConnection(configuration);
    // Setup stream listening

    theirConnection.onaddstream = function (e) {
        theirVideo.src = window.URL.createObjectURL(e.stream);
    };


    // Setup ice handling
    yourConnection.onicecandidate = function (event) {
        if (event.candidate) {
            theirConnection.addIceCandidate(new RTCIceCandidate(event.candidate));
        }

    };

    theirConnection.onicecandidate = function (event) {
        if (event.candidate) {
            yourConnection.addIceCandidate(new RTCIceCandidate(event.candidate));
        }
    };

    // Begin the offer
    yourConnection.createOffer(function (offer) {
        yourConnection.setLocalDescription(offer);
        theirConnection.setRemoteDescription(offer);

        theirConnection.createAnswer(function (offer) {
            theirConnection.setLocalDescription(offer);
            yourConnection.setRemoteDescription(offer);
        });
    });
}

Answer 1

你正在调用promise方法。问题实际上是你没有检查错误。

具体来说：您寻求的legacy callback methods至少需要两个参数：成功回调，和失败回调。

如果没有失败的回调，WebIDL名称重载会调用newer promise methods，而不会回调并返回一个承诺。

在任何地方传递所需的错误回调，例如：

yourConnection.createOffer(offer => { ... }, err => console.log(err));

或者更好，完全避免遗留方法：

function startPeerConnection(stream) {

  var config = { iceServers: [{ urls: "stun:127.0.0.1:8080" }] };

  yours = new RTCPeerConnection(config);
  theirs = new RTCPeerConnection(config);

  theirs.onaddstream = e => theirVideo.srcObject = e.stream;
  yours.onicecandidate = e => theirs.addIceCandidate(e.candidate);
  theirs.onicecandidate = e => yours.addIceCandidate(e.candidate);

  yours.addStream(stream); // <-- don't forget

  return yours.createOffer()
    .then(offer => Promise.all([yours.setLocalDescription(offer),
                                theirs.setRemoteDescription(offer)]))
    .then(() => theirs.createAnswer())
    .then(answer => Promise.all([theirs.setLocalDescription(answer),
                                 yours.setRemoteDescription(answer)]));
}
          
navigator.mediaDevices.getUserMedia({video: true, audio: true})
  .then(stream => startPeerConnection(stream))
  .catch(e => console.log(e));

<video id="theirVideo" height="120" width="160" autoplay></video>
<script src="https://webrtc.github.io/adapter/adapter-latest.js"></script>

始终检查错误。 createOffer错误告诉我您忘记了.addStream(stream)。

promise API可以在Firefox中本地使用，也可以通过Chrome中的adapter.js获得。

webrtc configration返回null值

1 个答案: