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|
/* global module */
const adapter = require('webrtc-adapter')
const util = require('util')
const webrtcSupport = require('webrtcsupport')
const WildEmitter = require('wildemitter')
/**
* @param {object} stream the stream object.
*/
function isAllTracksEnded(stream) {
let isAllTracksEnded = true
stream.getTracks().forEach(function(t) {
isAllTracksEnded = t.readyState === 'ended' && isAllTracksEnded
})
return isAllTracksEnded
}
/**
* @param {object} options the options object.
*/
function Peer(options) {
const self = this
// call emitter constructor
WildEmitter.call(this)
this.id = options.id
this.parent = options.parent
this.type = options.type || 'video'
this.oneway = options.oneway || false
this.sharemyscreen = options.sharemyscreen || false
this.stream = options.stream
this.receiverOnly = options.receiverOnly
this.sendVideoIfAvailable = options.sendVideoIfAvailable === undefined ? true : options.sendVideoIfAvailable
this.enableDataChannels = options.enableDataChannels === undefined ? this.parent.config.enableDataChannels : options.enableDataChannels
this.enableSimulcast = options.enableSimulcast === undefined ? this.parent.config.enableSimulcast : options.enableSimulcast
this.maxBitrates = options.maxBitrates === undefined ? this.parent.config.maxBitrates : options.maxBitrates
this.receiveMedia = options.receiveMedia || this.parent.config.receiveMedia
this.channels = {}
this.pendingDCMessages = [] // key (datachannel label) -> value (array[pending messages])
this._pendingReplaceTracksQueue = []
this._processPendingReplaceTracksPromise = null
this._initialStreamSetup = false
this.sid = options.sid || Date.now().toString()
this.pc = new RTCPeerConnection(this.parent.config.peerConnectionConfig)
this.pc.addEventListener('icecandidate', this.onIceCandidate.bind(this))
this.pc.addEventListener('endofcandidates', function(event) {
self.send('endOfCandidates', event)
})
this.pc.addEventListener('addstream', this.handleRemoteStreamAdded.bind(this))
this.pc.addEventListener('datachannel', this.handleDataChannelAdded.bind(this))
this.pc.addEventListener('removestream', this.handleStreamRemoved.bind(this))
// Just fire negotiation needed events for now
// When browser re-negotiation handling seems to work
// we can use this as the trigger for starting the offer/answer process
// automatically. We'll just leave it be for now while this stabalizes.
this.pc.addEventListener('negotiationneeded', this.emit.bind(this, 'negotiationNeeded'))
this.pc.addEventListener('iceconnectionstatechange', this.emit.bind(this, 'iceConnectionStateChange'))
this.pc.addEventListener('iceconnectionstatechange', function() {
if (!options.receiverOnly && self.pc.iceConnectionState !== 'new') {
self._processPendingReplaceTracks().then(finished => {
if (finished === false || self._initialStreamSetup) {
return
}
// Ensure that initially disabled tracks are stopped after
// establishing a connection.
self.pc.getSenders().forEach(sender => {
if (sender.track) {
// The stream is not known, but it is only used when the
// track is added, so it can be ignored here.
self.handleSentTrackEnabledChanged(sender.track, null)
}
})
self._initialStreamSetup = true
})
} else {
self._initialStreamSetup = false
}
switch (self.pc.iceConnectionState) {
case 'failed':
// currently, in chrome only the initiator goes to failed
// so we need to signal this to the peer
if (self.pc.localDescription.type === 'offer') {
self.parent.emit('iceFailed', self)
self.send('connectivityError')
}
break
}
})
this.pc.addEventListener('connectionstatechange', function() {
if (self.pc.connectionState !== 'failed') {
return
}
if (self.pc.iceConnectionState === 'failed') {
return
}
// Work around Chromium bug where "iceConnectionState" never changes to
// "failed" (it stays as "disconnected"). When that happens
// "connectionState" actually does change to "failed", so the normal
// handling of "iceConnectionState === failed" is triggered here.
if (self.pc.localDescription.type === 'offer') {
self.parent.emit('iceFailed', self)
self.send('connectivityError')
}
})
this.pc.addEventListener('signalingstatechange', this.emit.bind(this, 'signalingStateChange'))
this.logger = this.parent.logger
if (!options.receiverOnly) {
// handle screensharing/broadcast mode
if (options.type === 'screen') {
if (this.parent.localScreen && this.sharemyscreen) {
this.logger.log('adding local screen stream to peer connection')
this.pc.addStream(this.parent.localScreen)
this.broadcaster = options.broadcaster
}
} else {
this.parent.sentStreams.forEach(function(stream) {
stream.getTracks().forEach(function(track) {
if (track.kind !== 'video' || self.sendVideoIfAvailable) {
self.pc.addTrack(track, stream)
}
})
})
this.handleSentTrackReplacedBound = this.handleSentTrackReplaced.bind(this)
// TODO What would happen if the track is replaced while the peer is
// still negotiating the offer and answer?
this.parent.on('sentTrackReplaced', this.handleSentTrackReplacedBound)
this.handleSentTrackEnabledChangedBound = this.handleSentTrackEnabledChanged.bind(this)
this.parent.on('sentTrackEnabledChanged', this.handleSentTrackEnabledChangedBound)
}
}
// proxy events to parent
this.on('*', function() {
self.parent.emit.apply(self.parent, arguments)
})
}
util.inherits(Peer, WildEmitter)
// Helper method to munge an SDP to enable simulcasting (Chrome only)
// Taken from janus.js (MIT license).
/* eslint-disable */
function mungeSdpForSimulcasting(sdp) {
// Let's munge the SDP to add the attributes for enabling simulcasting
// (based on https://gist.github.com/ggarber/a19b4c33510028b9c657)
var lines = sdp.split("\r\n");
var video = false;
var ssrc = [ -1 ], ssrc_fid = [ -1 ];
var cname = null, msid = null, mslabel = null, label = null;
var insertAt = -1;
for(var i=0; i<lines.length; i++) {
var mline = lines[i].match(/m=(\w+) */);
if(mline) {
var medium = mline[1];
if(medium === "video") {
// New video m-line: make sure it's the first one
if(ssrc[0] < 0) {
video = true;
} else {
// We're done, let's add the new attributes here
insertAt = i;
break;
}
} else {
// New non-video m-line: do we have what we were looking for?
if(ssrc[0] > -1) {
// We're done, let's add the new attributes here
insertAt = i;
break;
}
}
continue;
}
if(!video)
continue;
var fid = lines[i].match(/a=ssrc-group:FID (\d+) (\d+)/);
if(fid) {
ssrc[0] = fid[1];
ssrc_fid[0] = fid[2];
lines.splice(i, 1); i--;
continue;
}
if(ssrc[0]) {
var match = lines[i].match('a=ssrc:' + ssrc[0] + ' cname:(.+)')
if(match) {
cname = match[1];
}
match = lines[i].match('a=ssrc:' + ssrc[0] + ' msid:(.+)')
if(match) {
msid = match[1];
}
match = lines[i].match('a=ssrc:' + ssrc[0] + ' mslabel:(.+)')
if(match) {
mslabel = match[1];
}
match = lines[i].match('a=ssrc:' + ssrc[0] + ' label:(.+)')
if(match) {
label = match[1];
}
if(lines[i].indexOf('a=ssrc:' + ssrc_fid[0]) === 0) {
lines.splice(i, 1); i--;
continue;
}
if(lines[i].indexOf('a=ssrc:' + ssrc[0]) === 0) {
lines.splice(i, 1); i--;
continue;
}
}
if(lines[i].length == 0) {
lines.splice(i, 1); i--;
continue;
}
}
if(ssrc[0] < 0) {
// Couldn't find a FID attribute, let's just take the first video SSRC we find
insertAt = -1;
video = false;
for(var i=0; i<lines.length; i++) {
var mline = lines[i].match(/m=(\w+) */);
if(mline) {
var medium = mline[1];
if(medium === "video") {
// New video m-line: make sure it's the first one
if(ssrc[0] < 0) {
video = true;
} else {
// We're done, let's add the new attributes here
insertAt = i;
break;
}
} else {
// New non-video m-line: do we have what we were looking for?
if(ssrc[0] > -1) {
// We're done, let's add the new attributes here
insertAt = i;
break;
}
}
continue;
}
if(!video)
continue;
if(ssrc[0] < 0) {
var value = lines[i].match(/a=ssrc:(\d+)/);
if(value) {
ssrc[0] = value[1];
lines.splice(i, 1); i--;
continue;
}
} else {
var match = lines[i].match('a=ssrc:' + ssrc[0] + ' cname:(.+)')
if(match) {
cname = match[1];
}
match = lines[i].match('a=ssrc:' + ssrc[0] + ' msid:(.+)')
if(match) {
msid = match[1];
}
match = lines[i].match('a=ssrc:' + ssrc[0] + ' mslabel:(.+)')
if(match) {
mslabel = match[1];
}
match = lines[i].match('a=ssrc:' + ssrc[0] + ' label:(.+)')
if(match) {
label = match[1];
}
if(lines[i].indexOf('a=ssrc:' + ssrc_fid[0]) === 0) {
lines.splice(i, 1); i--;
continue;
}
if(lines[i].indexOf('a=ssrc:' + ssrc[0]) === 0) {
lines.splice(i, 1); i--;
continue;
}
}
if(lines[i].length === 0) {
lines.splice(i, 1); i--;
continue;
}
}
}
if(ssrc[0] < 0) {
// Still nothing, let's just return the SDP we were asked to munge
console.warn("Couldn't find the video SSRC, simulcasting NOT enabled");
return sdp;
}
if(insertAt < 0) {
// Append at the end
insertAt = lines.length;
}
// Generate a couple of SSRCs (for retransmissions too)
// Note: should we check if there are conflicts, here?
ssrc[1] = Math.floor(Math.random()*0xFFFFFFFF);
ssrc[2] = Math.floor(Math.random()*0xFFFFFFFF);
ssrc_fid[1] = Math.floor(Math.random()*0xFFFFFFFF);
ssrc_fid[2] = Math.floor(Math.random()*0xFFFFFFFF);
// Add attributes to the SDP
for(var i=0; i<ssrc.length; i++) {
if(cname) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc[i] + ' cname:' + cname);
insertAt++;
}
if(msid) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc[i] + ' msid:' + msid);
insertAt++;
}
if(mslabel) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc[i] + ' mslabel:' + mslabel);
insertAt++;
}
if(label) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc[i] + ' label:' + label);
insertAt++;
}
// Add the same info for the retransmission SSRC
if(cname) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc_fid[i] + ' cname:' + cname);
insertAt++;
}
if(msid) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc_fid[i] + ' msid:' + msid);
insertAt++;
}
if(mslabel) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc_fid[i] + ' mslabel:' + mslabel);
insertAt++;
}
if(label) {
lines.splice(insertAt, 0, 'a=ssrc:' + ssrc_fid[i] + ' label:' + label);
insertAt++;
}
}
lines.splice(insertAt, 0, 'a=ssrc-group:FID ' + ssrc[2] + ' ' + ssrc_fid[2]);
lines.splice(insertAt, 0, 'a=ssrc-group:FID ' + ssrc[1] + ' ' + ssrc_fid[1]);
lines.splice(insertAt, 0, 'a=ssrc-group:FID ' + ssrc[0] + ' ' + ssrc_fid[0]);
lines.splice(insertAt, 0, 'a=ssrc-group:SIM ' + ssrc[0] + ' ' + ssrc[1] + ' ' + ssrc[2]);
sdp = lines.join("\r\n");
if(!sdp.endsWith("\r\n"))
sdp += "\r\n";
return sdp;
}
/* eslint-enable */
Peer.prototype.offer = function(options) {
const sendVideo = this.sendVideoIfAvailable && this.type !== 'screen'
if (sendVideo && this.enableSimulcast && adapter.browserDetails.browser === 'firefox') {
console.debug('Enabling Simulcasting for Firefox (RID)')
const sender = this.pc.getSenders().find(function(s) {
return s.track.kind === 'video'
})
if (sender) {
let parameters = sender.getParameters()
if (!parameters) {
parameters = {}
}
parameters.encodings = [
{
rid: 'h',
active: true,
maxBitrate: this.maxBitrates.high,
},
{
rid: 'm',
active: true,
maxBitrate: this.maxBitrates.medium,
scaleResolutionDownBy: 2,
},
{
rid: 'l',
active: true,
maxBitrate: this.maxBitrates.low,
scaleResolutionDownBy: 4,
},
]
sender.setParameters(parameters)
}
}
this.pc.createOffer(options).then(function(offer) {
if (sendVideo && this.enableSimulcast) {
// This SDP munging only works with Chrome (Safari STP may support it too)
if (adapter.browserDetails.browser === 'chrome' || adapter.browserDetails.browser === 'safari') {
console.debug('Enabling Simulcasting for Chrome (SDP munging)')
offer.sdp = mungeSdpForSimulcasting(offer.sdp)
} else if (adapter.browserDetails.browser !== 'firefox') {
console.debug('Simulcast can only be enabled on Chrome or Firefox')
}
}
this.pc.setLocalDescription(offer).then(function() {
if (this.parent.config.nick) {
// The offer is a RTCSessionDescription that only serializes
// its own attributes to JSON, so if extra attributes are needed
// a regular object has to be sent instead.
offer = {
type: offer.type,
sdp: offer.sdp,
nick: this.parent.config.nick,
}
}
this.send('offer', offer)
}.bind(this)).catch(function(error) {
console.warn('setLocalDescription for offer failed: ', error)
})
}.bind(this)).catch(function(error) {
console.warn('createOffer failed: ', error)
})
}
Peer.prototype.handleOffer = function(offer) {
this.pc.setRemoteDescription(offer).then(function() {
this._blockRemoteVideoIfNeeded()
this.answer()
}.bind(this)).catch(function(error) {
console.warn('setRemoteDescription for offer failed: ', error)
})
}
Peer.prototype._getTransceiverKind = function(transceiver) {
// Transceivers for HPB subscribers have the transceiver kind in its mid.
if (transceiver.mid === 'audio' || transceiver.mid === 'video') {
return transceiver.mid
}
// In general, the transceiver kind can be got from the receiver track, as
// it will always be there, even if the transceiver is inactive or the
// remote sender never had a track.
if (transceiver.receiver && transceiver.receiver.track) {
return transceiver.receiver.track.kind
}
console.debug('Transceiver kind could not be determined: ', transceiver)
return null
}
/**
* Blocks remote video based on "_remoteVideoShouldBeBlocked".
*
* 'remoteVideoBlocked' is emitted if the blocked state changes.
*
* Currently remote video can be blocked only when the HPB is used, so this
* method should be called immediately before creating the answer (the answer
* must be created in the same "tick" that this method is called).
*
* Note that if the transceiver direction changes after creating the answer but
* before setting it as the local description the "negotiationneeded" event will
* be automatically emitted again.
*/
Peer.prototype._blockRemoteVideoIfNeeded = function() {
const remoteVideoWasBlocked = this._remoteVideoBlocked
this._remoteVideoBlocked = undefined
this.pc.getTransceivers().forEach(transceiver => {
if (transceiver.mid === 'video' && !transceiver.stopped) {
if (this._remoteVideoShouldBeBlocked) {
transceiver.direction = 'inactive'
this._remoteVideoBlocked = true
} else {
this._remoteVideoBlocked = false
}
}
})
if (remoteVideoWasBlocked !== this._remoteVideoBlocked) {
this.emit('remoteVideoBlocked', this._remoteVideoBlocked)
}
}
Peer.prototype.answer = function() {
this.pc.createAnswer().then(function(answer) {
this.pc.setLocalDescription(answer).then(function() {
if (this.parent.config.nick) {
// The answer is a RTCSessionDescription that only serializes
// its own attributes to JSON, so if extra attributes are needed
// a regular object has to be sent instead.
answer = {
type: answer.type,
sdp: answer.sdp,
nick: this.parent.config.nick,
}
}
this.send('answer', answer)
}.bind(this)).catch(function(error) {
console.warn('setLocalDescription for answer failed: ', error)
})
}.bind(this)).catch(function(error) {
console.warn('createAnswer failed: ', error)
})
}
Peer.prototype.handleAnswer = function(answer) {
this.pc.setRemoteDescription(answer).catch(function(error) {
console.warn('setRemoteDescription for answer failed: ', error)
})
}
Peer.prototype.selectSimulcastStream = function(substream, temporal) {
if (this.substream === substream && this.temporal === temporal) {
return
}
console.debug('Changing simulcast stream', this.id, this, substream, temporal)
this.send('selectStream', {
substream,
temporal,
})
this.substream = substream
this.temporal = temporal
}
Peer.prototype.handleMessage = function(message) {
const self = this
this.logger.log('getting', message.type, message)
if (message.type === 'offer') {
if (!this.nick) {
this.nick = message.payload.nick
}
delete message.payload.nick
this.handleOffer(message.payload)
} else if (message.type === 'answer') {
if (!this.nick) {
this.nick = message.payload.nick
}
delete message.payload.nick
this.handleAnswer(message.payload)
} else if (message.type === 'candidate') {
this.pc.addIceCandidate(message.payload.candidate)
} else if (message.type === 'connectivityError') {
this.parent.emit('connectivityError', self)
} else if (message.type === 'mute') {
this.parent.emit('mute', { id: message.from, name: message.payload.name })
} else if (message.type === 'unmute') {
this.parent.emit('unmute', { id: message.from, name: message.payload.name })
} else if (message.type === 'endOfCandidates') {
this.pc.addIceCandidate('')
} else if (message.type === 'unshareScreen') {
this.parent.emit('unshareScreen', { id: message.from })
this.end()
}
}
// send via signalling channel
Peer.prototype.send = function(messageType, payload) {
const message = {
to: this.id,
sid: this.sid,
broadcaster: this.broadcaster,
roomType: this.type,
type: messageType,
payload,
}
this.logger.log('sending', messageType, message)
this.parent.emit('message', message)
}
// send via data channel
// returns true when message was sent and false if channel is not open
Peer.prototype.sendDirectly = function(channel, messageType, payload) {
const message = {
type: messageType,
payload,
}
this.logger.log('sending via datachannel', channel, messageType, message)
const dc = this.getDataChannel(channel)
if (!dc) {
return false
}
if (dc.readyState !== 'open') {
if (!Object.prototype.hasOwnProperty.call(this.pendingDCMessages, channel)) {
this.pendingDCMessages[channel] = []
}
this.pendingDCMessages[channel].push(message)
return false
}
dc.send(JSON.stringify(message))
return true
}
// Internal method registering handlers for a data channel and emitting events on the peer
Peer.prototype._observeDataChannel = function(channel) {
const self = this
channel.onclose = this.emit.bind(this, 'channelClose', channel)
channel.onerror = this.emit.bind(this, 'channelError', channel)
channel.onmessage = function(event) {
self.emit('channelMessage', self, channel.label, JSON.parse(event.data), channel, event)
}
channel.onopen = function() {
self.emit('channelOpen', channel)
// Check if there are messages that could not be send
if (Object.prototype.hasOwnProperty.call(self.pendingDCMessages, channel.label)) {
const pendingMessages = self.pendingDCMessages[channel.label].slice()
self.pendingDCMessages[channel.label] = []
for (let i = 0; i < pendingMessages.length; i++) {
self.sendDirectly(channel.label, pendingMessages[i].type, pendingMessages[i].payload)
}
}
}
}
// Fetch or create a data channel by the given name
Peer.prototype.getDataChannel = function(name, opts) {
if (!webrtcSupport.supportDataChannel) {
return this.emit('error', new Error('createDataChannel not supported'))
}
if (!this.enableDataChannels) {
return null
}
let channel = this.channels[name]
opts || (opts = {})
if (channel) {
return channel
}
// if we don't have one by this label, create it
channel = this.channels[name] = this.pc.createDataChannel(name, opts)
this._observeDataChannel(channel)
return channel
}
Peer.prototype.onIceCandidate = function(event) {
const candidate = event.candidate
if (this.closed) {
return
}
if (candidate) {
// Retain legacy data structure for compatibility with
// mobile clients.
const expandedCandidate = {
candidate: {
candidate: candidate.candidate,
sdpMid: candidate.sdpMid,
sdpMLineIndex: candidate.sdpMLineIndex,
},
}
this.send('candidate', expandedCandidate)
} else {
this.logger.log('End of candidates.')
}
}
Peer.prototype.start = function() {
// well, the webrtc api requires that we either
// a) create a datachannel a priori
// b) do a renegotiation later to add the SCTP m-line
// Let's do (a) first...
this.getDataChannel('simplewebrtc')
this.offer(this.receiveMedia)
}
Peer.prototype.icerestart = function() {
const constraints = this.receiveMedia
constraints.iceRestart = true
this.offer(constraints)
}
Peer.prototype.end = function() {
if (this.closed) {
return
}
this.pc.close()
this.handleStreamRemoved()
this.parent.off('sentTrackReplaced', this.handleSentTrackReplacedBound)
this.parent.off('sentTrackEnabledChanged', this.handleSentTrackEnabledChangedBound)
this.parent.emit('peerEnded', this)
}
Peer.prototype.handleSentTrackReplaced = function(newTrack, oldTrack, stream) {
this._pendingReplaceTracksQueue.push({ newTrack, oldTrack, stream })
this._processPendingReplaceTracks()
}
/**
* Process pending replace track actions.
*
* All the pending replace track actions are executed from the oldest to the
* newest, waiting until the previous action was executed before executing the
* next one.
*
* The process may be stopped if the connection is lost, or if a track needs to
* be added rather than replaced, which requires a renegotiation. In both cases
* the process will start again once the connection is restablished.
*
* @return {Promise} a Promise fulfilled when the processing ends; if it was
* completed the resolved value is true, and if it was stopped before
* finishing the resolved value is false.
*/
Peer.prototype._processPendingReplaceTracks = function() {
if (this._processPendingReplaceTracksPromise) {
return this._processPendingReplaceTracksPromise
}
this._processPendingReplaceTracksPromise = this._processPendingReplaceTracksAsync()
// For compatibility with older browsers "finally" should not be used on
// Promises.
this._processPendingReplaceTracksPromise.then(() => {
this._processPendingReplaceTracksPromise = null
}).catch(() => {
this._processPendingReplaceTracksPromise = null
})
return this._processPendingReplaceTracksPromise
}
Peer.prototype._processPendingReplaceTracksAsync = async function() {
while (this._pendingReplaceTracksQueue.length > 0) {
if (this.pc.iceConnectionState === 'new') {
// Do not replace the tracks when the connection has not started
// yet, as Firefox can get "stuck" and not replace the tracks even
// if tried later again once connected.
return false
}
const pending = this._pendingReplaceTracksQueue.shift()
try {
await this._replaceTrack(pending.newTrack, pending.oldTrack, pending.stream)
} catch (exception) {
// If the track is added instead of replaced a renegotiation will be
// needed, so stop replacing tracks.
return false
}
}
return true
}
/**
* Replaces the old track with the new track in the appropriate sender.
*
* If the new track is disabled the old track will be replaced by a null track
* instead, which stops the sent data. The old and new tracks can be the same
* track, which can be used to start or stop sending the track data depending on
* whether the track is enabled or disabled (at the time of being passed to this
* method).
*
* If a new track is provided but no sender was found the new track is added
* instead of replaced (which will require a renegotiation).
*
* The method returns a promise which is fulfilled once the track was replaced
* in the appropriate sender, or immediately if no sender was found and no track
* was added. If a track had to be added the promise is rejected instead.
*
* @param {MediaStreamTrack|null} newTrack the new track to set.
* @param {MediaStreamTrack|null} oldTrack the old track to be replaced.
* @param {MediaStream} stream the stream that the new track belongs to.
* @return {Promise}
*/
Peer.prototype._replaceTrack = async function(newTrack, oldTrack, stream) {
let senderFound = false
// The track should be replaced in just one sender, but an array of promises
// is used to be on the safe side.
const replaceTrackPromises = []
this.pc.getSenders().forEach(sender => {
if (sender.track !== oldTrack && sender.trackDisabled !== oldTrack) {
return
}
if ((sender.track || sender.trackDisabled) && !oldTrack) {
return
}
if (!sender.track && !newTrack) {
// The old track was disabled and thus already stopped, so it does
// not need to be replaced, but the null track needs to be set as
// the disabled track.
if (sender.trackDisabled === oldTrack) {
sender.trackDisabled = newTrack
}
return
}
if (!sender.kind && sender.track) {
sender.kind = sender.track.kind
} else if (!sender.kind && sender.trackDisabled) {
sender.kind = sender.trackDisabled.kind
} else if (!sender.kind) {
this.pc.getTransceivers().forEach(transceiver => {
if (transceiver.sender === sender) {
sender.kind = this._getTransceiverKind(transceiver)
}
})
}
// A null track can match on audio and video senders, so it needs to be
// ensured that the sender kind and the new track kind are compatible.
// However, in some cases it may not be possible to know the sender
// kind. In those cases just go ahead and try to replace the track; if
// the kind does not match then replacing the track will fail, but this
// should not prevent replacing the track with a proper one later, nor
// affect any other sender.
if (!sender.track && sender.kind && sender.kind !== newTrack.kind) {
return
}
senderFound = true
// Save reference to trackDisabled to be able to restore it if the track
// can not be replaced.
const oldTrackDisabled = sender.trackDisabled
if (newTrack && !newTrack.enabled) {
sender.trackDisabled = newTrack
} else {
sender.trackDisabled = null
}
if (!sender.track && !newTrack.enabled) {
// Nothing to replace now, it will be done once the track is
// enabled.
return
}
if (sender.track && newTrack && !newTrack.enabled) {
// Replace with a null track to stop the sender.
newTrack = null
}
const replaceTrackPromise = sender.replaceTrack(newTrack)
replaceTrackPromise.catch(error => {
sender.trackDisabled = oldTrackDisabled
if (error.name === 'InvalidModificationError') {
console.debug('Track could not be replaced, negotiation needed')
} else {
console.error('Track could not be replaced: ', error, oldTrack, newTrack)
}
})
replaceTrackPromises.push(replaceTrackPromise)
})
// If the call started when the audio or video device was not active there
// will be no sender for that type. In that case the track needs to be added
// instead of replaced.
if (!senderFound && newTrack) {
this.pc.addTrack(newTrack, stream)
return Promise.reject(new Error('Track added instead of replaced'))
}
return Promise.allSettled(replaceTrackPromises)
}
Peer.prototype.handleSentTrackEnabledChanged = function(track, stream) {
const sender = this.pc.getSenders().find(sender => sender.track === track)
const stoppedSender = this.pc.getSenders().find(sender => sender.trackDisabled === track)
if (track.enabled && stoppedSender) {
this.handleSentTrackReplacedBound(track, track, stream)
} else if (!track.enabled && sender) {
this.handleSentTrackReplacedBound(track, track, stream)
}
}
Peer.prototype.setRemoteVideoBlocked = function(remoteVideoBlocked) {
// If the HPB is not used or if it is used and this is a sender peer the
// remote video can not be blocked.
// Besides that the remote video is not blocked either if the signaling
// server does not support updating the subscribers; in that case a new
// connection would need to be established and due to this the audio would
// be interrupted during the connection change.
if (!this.receiverOnly || !this.parent.config.connection.hasFeature('update-sdp')) {
return
}
// If the HPB is used the remote video can be blocked through a standard
// WebRTC renegotiation or by toggling the video directly in Janus. The last
// one is preferred, as it requires less signaling messages to be exchanged
// and, besides that, the browser starts to decode the video faster once
// enabled again.
if (this.receiverOnly && this.parent.config.connection.hasFeature('update-sdp')) {
this.send('selectStream', {
video: !remoteVideoBlocked,
})
return
}
this._remoteVideoShouldBeBlocked = remoteVideoBlocked
// The "negotiationneeded" event is emitted if needed based on the direction
// changes.
// Note that there will be a video transceiver even if the remote
// participant is sending a null video track (either because there is a
// camera but the video is disabled or because the camera was removed during
// the call), so a renegotiation could be needed also in that case.
this.pc.getTransceivers().forEach(transceiver => {
if (transceiver.mid === 'video' && !transceiver.stopped) {
if (remoteVideoBlocked) {
transceiver.direction = 'inactive'
} else {
transceiver.direction = 'recvonly'
}
}
})
}
Peer.prototype.handleRemoteStreamAdded = function(event) {
const self = this
if (this.stream) {
this.logger.warn('Already have a remote stream')
} else {
this.stream = event.stream
this.stream.getTracks().forEach(function(track) {
track.addEventListener('ended', function() {
if (isAllTracksEnded(self.stream)) {
self.end()
}
})
})
this.parent.emit('peerStreamAdded', this)
}
}
Peer.prototype.handleStreamRemoved = function() {
const peerIndex = this.parent.peers.indexOf(this)
if (peerIndex > -1) {
this.parent.peers.splice(peerIndex, 1)
this.closed = true
this.parent.emit('peerStreamRemoved', this)
}
}
Peer.prototype.handleDataChannelAdded = function(event) {
const channel = event.channel
this.channels[channel.label] = channel
this._observeDataChannel(channel)
}
module.exports = Peer
|