RTC peer connection doesn't establish - webrtc

Question

I read about WebRTC in MDN and tried to open peer connection. I decided to open both local and remote connections in one page, and wrote this code:
const configuration = {iceServers: [
{urls: 'stun:stun.l.google.com:19302'},
{urls: 'stun:stun1.l.google.com:19302'},
]};
const localConnection = new RTCPeerConnection(configuration);
const remoteConnection = new RTCPeerConnection(configuration);
let localSendChannel, remoteSendChannel;
localConnection.onicecandidate = ({candidate}) => {
console.log('local candidate', candidate);
if (candidate) remoteConnection.addIceCandidate(candidate)
}
remoteConnection.onicecandidate = ({candidate}) => {
console.log('remote candidate', candidate);
if (candidate) localConnection.addIceCandidate(candidate)
}
const connect = async () => {
const offer = await localConnection.createOffer();
console.log('local offer', offer);
await localConnection.setLocalDescription(offer);
console.log('local localDescription', localConnection.localDescription);
await remoteConnection.setRemoteDescription(localConnection.localDescription);
const answer = await remoteConnection.createAnswer();
await remoteConnection.setLocalDescription(answer);
console.log('remote answer', answer);
console.log('remote localDescription', remoteConnection.localDescription);
await localConnection.setRemoteDescription(remoteConnection.localDescription);
localConnection.addEventListener('connectionstatechange', (e) => {
console.log('localConnection new state', e.connectionState);
});
remoteConnection.addEventListener('connectionstatechange', (e) => {
console.log('remoteConnection new state', e.connectionState);
});
const gumStream = await navigator.mediaDevices.getUserMedia({video: false, audio: true});
for (const track of gumStream.getTracks())
localConnection.addTrack(track);
}
const openLocalChannel = async () => {
localSendChannel = localConnection.createDataChannel("sendChannel");
localSendChannel.onopen = () => {
console.log('local datachannel was opened');
localSendChannel.send("Hello, world!")
}
localSendChannel.onclose = () => console.log('local datachannel was closed');
localSendChannel.onmessage = (msg) => console.log('local channel got message', msg);
}
const waitRemoteChannel = () => {
remoteConnection.ondatachannel = (e) => {
remoteSendChannel = e.channel;
console.log('remote atachannel was init');
remoteSendChannel.onopen = () => console.log('remote datachannel was opened');
remoteSendChannel.onclose = () => console.log('remote datachannel was closed');
remoteSendChannel.onmessage = (msg) => console.log('remote channel got message', msg);
};
}
const start = async () => {
await connect();
waitRemoteChannel();
await openLocalChannel();
localConnection.addEventListener('connectionstatechange', async (e) => {
console.log('localConnection new state', e.connectionState);
});
remoteConnection.addEventListener('connectionstatechange', (e) => {
console.log('localConnection new state', e.connectionState);
});
}
start();
I haven't any candidates in Chrome and have only null candidates in FireFox. Can you point, where is mistake?
Updated: I added to the code media tracks adding and trying of create datachannel after connection create. But problem is staying

Answer 1

You are not doing anything with the connection, neither adding a track nor creating a datachannel. As a result the offer will be formally valid but will not cause ice candidates to be gathered and without candidates there will be no connection.