bigbluebutton-Github/bigbluebutton-html5/imports/utils/safari-webrtc.js
prlanzarin 2cba85e866 html5: refactor STUN/TURN fetch, add fallback STUN, fix deadlock in audio join
Refactored STUN/TURN fetch to be done only once, when successful, per session and cache it in mem to avoid too many reqs. Current way is a bit dumb, this should increase reliability a bit more. The caching is configurable so folks who want to use very short lived TURN credentials can disable it

Add a fallback STUN config option to be used when the default STUN/TURN fetch fails

Clean the safari/no candidate generation pre flight check from 3rd party STUNs

Fix deadlock in audio join when STUN/TURN fetch failed
2020-05-21 04:35:17 +00:00

90 lines
3.0 KiB
JavaScript

import {
fetchWebRTCMappedStunTurnServers,
getMappedFallbackStun,
} from '/imports/utils/fetchStunTurnServers';
import Auth from '/imports/ui/services/auth';
import { Session } from 'meteor/session';
import logger from '/imports/startup/client/logger';
const getSessionToken = () => Auth.sessionToken;
export async function getIceServersList() {
try {
const iceServers = await fetchWebRTCMappedStunTurnServers(getSessionToken());
return iceServers;
} catch (error) {
return getMappedFallbackStun();
}
}
export function canGenerateIceCandidates() {
return new Promise((resolve, reject) => {
if (Session.get('canGenerateIceCandidates')) {
resolve();
return;
}
getIceServersList().catch((e) => {
reject(e);
}).then((iceServersReceived) => {
const pc = new RTCPeerConnection({ iceServers: iceServersReceived });
let countIceCandidates = 0;
try { pc.addTransceiver('audio'); } catch (e) { }
pc.onicecandidate = function (e) {
if (countIceCandidates) return;
if (e.candidate && e.candidate.candidate.indexOf('.local') === -1) {
countIceCandidates++;
Session.set('canGenerateIceCandidates', true);
resolve();
}
};
pc.onicegatheringstatechange = function (e) {
if (e.currentTarget.iceGatheringState === 'complete' && countIceCandidates === 0) {
logger.warn({ logCode: 'no_valid_candidate' }, 'No useful ICE candidate found. Will request gUM permission.');
reject();
}
};
setTimeout(() => {
pc.close();
if (!countIceCandidates) reject();
}, 5000);
const p = pc.createOffer({ offerToReceiveVideo: true });
p.then((answer) => { pc.setLocalDescription(answer); });
});
});
}
/*
* Try to generate candidates for a recvonly RTCPeerConnection without
* a gUM permission and check if there are any candidates generated other than
* a mDNS host candidate. If there aren't, forcefully request gUM permission
* for mic (best chance of a gUM working is mic) to try and make the browser
* generate at least srflx candidates.
* This is a workaround due to a behaviour some browsers display (mainly Safari)
* where they won't generate srflx or relay candidates if no gUM permission is
* given. Since our media servers aren't able to make it work by prflx
* candidates, we need to do this.
*/
export function tryGenerateIceCandidates() {
return new Promise((resolve, reject) => {
canGenerateIceCandidates().then(() => {
resolve();
}).catch(() => {
navigator.mediaDevices.getUserMedia({ audio: true, video: false }).then(() => {
logger.info({ logCode: 'no_valid_candidate_gum_success' }, 'Forced gUM to release additional ICE candidates succeeded.');
canGenerateIceCandidates().then(() => {
resolve();
}).catch((error) => {
reject(error);
});
}).catch((error) => {
reject(error);
});
});
});
}