WebRTC short localhost example

WebRTCExample.js

function makePeerConnection()
{
    var myPeerConnection = new RTCPeerConnection(
        {
            iceServers: [
                /*{
                    urls: "turn:192.168.137.3:3478",
                    username: "guest",
                    credential: "*********"
                }*/
            ]
        },
        {
            'mandatory': {
                'OfferToReceiveAudio': false,
                'OfferToReceiveVideo': false
            }
        }
    );

    return myPeerConnection;
}

(async ()=>{
    const connectionA=makePeerConnection();
    const connectionB=makePeerConnection();
    let dataChannelB;

    const dataChannelA = connectionA.createDataChannel("jsonrpc");

    dataChannelA.onmessage = (event) => {
        console.log(event.data);
        dataChannelA.send(JSON.stringify({result:1234,jsonrpc:"2.0",id:null}));
    };
    dataChannelA.onerror = console.error;

    connectionA.onicecandidate = (event) => {
        connectionB.addIceCandidate(event.candidate).catch(()=>{});
    };

    connectionB.onicecandidate = (event) => {
        connectionA.addIceCandidate(event.candidate).catch(()=>{});
    };

    connectionB.ondatachannel = (event) => {
        dataChannelB = event.channel;

        dataChannelB.onmessage = (event) => {console.log(event.data)};
        dataChannelB.send(JSON.stringify({method:"arici",params:[],jsonrpc:"2.0",id:null}));
    };

    const offer = await connectionA.createOffer();
    await connectionA.setLocalDescription(new RTCSessionDescription(offer));

    await connectionB.setRemoteDescription(new RTCSessionDescription(offer));
    const answer = await connectionB.createAnswer();
    await connectionB.setLocalDescription(answer);

    await connectionA.setRemoteDescription(answer);
})();