WebRTC + Adapter.js giving addremoteCandidate error while connecting audio call in MS Edge

Question

I am trying to connect audio call through sipML5 API in MS edge using webrtc and adapter.js, but it gives error Timeout for addremoteCandidate. Consider sending an end-of-candidates notification.

I already tried sending addIceCandidate(null) as mentioned here but it is not working or may be i am sending it wrong. I googled but there is not enough documentation on this.

My question is where and how can i send addIceCandidate(null) so adapter.js will consider it ?

My RTCPeerConnection code

this.o_pc = new window.RTCPeerConn(a && !a.length ? null : {
            iceServers: a, 
            rtcpMuxPolicy: "negotiate",
            iceTransportPolicy: "all",
            bundlePolicy: "balanced",
            iceCandidatePoolSize: 0
            //gatherPolicy: "all",

        }, this.o_media_constraints);
        this.o_pc.onicecandidate = tmedia_session_jsep01.mozThis ? tmedia_session_jsep01.onIceCandidate : function(e) {
            tmedia_session_jsep01.onIceCandidate(e, c);
        };
        this.o_pc.onnegotiationneeded = tmedia_session_jsep01.mozThis ? tmedia_session_jsep01.onNegotiationNeeded : function(e) {
            tmedia_session_jsep01.onNegotiationNeeded(e, c);
        };
        this.o_pc.onsignalingstatechange = tmedia_session_jsep01.mozThis ? tmedia_session_jsep01.onSignalingstateChange : function(e) {
            tmedia_session_jsep01.onSignalingstateChange(e, c);
        };

this.o_media_constraints = {
        audio: true
    };
    if (tsk_utils_get_navigator_friendly_name() == "firefox") {
        tmedia_session_jsep01.mozThis = this;
        this.o_media_constraints.mandatory.MozDontOfferDataChannel = true;
    }

Any help would be appreciated.

Thanks

Answer 1

This warning indicates that you never call addIceCandidate(null). When the other end finishes with candidate gathering, i.e. pc.onicecandidate(event) is called event.candidate not set. Then you need to send a signaling message like e.g. {type: 'end-of-candidates'} which will cause addIceCandidate(null) to be called in Edge.

If you do not do that, adapter.js (or rather the Edge/ORTC shim) will do this for you after some time but this is far from optimal.