/**
* The list of Peer connection states.
* @attribute HANDSHAKE_PROGRESS
* @param {String} ENTER <small>Value <code>"enter"</code></small>
* The value of the connection state when Peer has just entered the Room.
* <small>At this stage, <a href="#event_peerJoined"><code>peerJoined</code> event</a>
* is triggered.</small>
* @param {String} WELCOME <small>Value <code>"welcome"</code></small>
* The value of the connection state when Peer is aware that User has entered the Room.
* <small>At this stage, <a href="#event_peerJoined"><code>peerJoined</code> event</a>
* is triggered and Peer connection may commence.</small>
* @param {String} OFFER <small>Value <code>"offer"</code></small>
* The value of the connection state when Peer connection has set the local / remote <code>"offer"</code>
* session description to start streaming connection.
* @param {String} ANSWER <small>Value <code>"answer"</code></small>
* The value of the connection state when Peer connection has set the local / remote <code>"answer"</code>
* session description to establish streaming connection.
* @param {String} ERROR <small>Value <code>"error"</code></small>
* The value of the connection state when Peer connection has failed to establish streaming connection.
* <small>This happens when there are errors that occurs in creating local <code>"offer"</code> /
* <code>"answer"</code>, or when setting remote / local <code>"offer"</code> / <code>"answer"</code>.</small>
* @type JSON
* @readOnly
* @for Skylink
* @since 0.1.0
*/
Skylink.prototype.HANDSHAKE_PROGRESS = {
ENTER: 'enter',
WELCOME: 'welcome',
OFFER: 'offer',
ANSWER: 'answer',
ERROR: 'error'
};
/**
* Function that creates the Peer connection offer session description.
* @method _doOffer
* @private
* @for Skylink
* @since 0.5.2
*/
Skylink.prototype._doOffer = function(targetMid, iceRestart, peerBrowser) {
var self = this;
var pc = self._peerConnections[targetMid] || self._addPeer(targetMid, peerBrowser);
log.log([targetMid, null, null, 'Checking caller status'], peerBrowser);
// Added checks to ensure that connection object is defined first
if (!pc) {
log.warn([targetMid, 'RTCSessionDescription', 'offer', 'Dropping of creating of offer ' +
'as connection does not exists']);
return;
}
// Added checks to ensure that state is "stable" if setting local "offer"
if (pc.signalingState !== self.PEER_CONNECTION_STATE.STABLE) {
log.warn([targetMid, 'RTCSessionDescription', 'offer',
'Dropping of creating of offer as signalingState is not "' +
self.PEER_CONNECTION_STATE.STABLE + '" ->'], pc.signalingState);
return;
}
var peerIceRestartSupport = !!((self._peerInformations[targetMid] || {}).config || {}).enableIceRestart;
var offerConstraints = {
offerToReceiveAudio: true,
offerToReceiveVideo: true,
iceRestart: self._enableIceRestart && peerIceRestartSupport ? iceRestart === true : false
};
// NOTE: Removing ICE restart functionality as of now since Firefox does not support it yet
// Check if ICE connection failed or disconnected, and if so, do an ICE restart
/*if ([self.ICE_CONNECTION_STATE.DISCONNECTED, self.ICE_CONNECTION_STATE.FAILED].indexOf(pc.iceConnectionState) > -1) {
offerConstraints.iceRestart = true;
}*/
// Prevent undefined OS errors
peerBrowser.os = peerBrowser.os || '';
/*
Ignoring these old codes as Firefox 39 and below is no longer supported
if (window.webrtcDetectedType === 'moz' && peerBrowser.agent === 'MCU') {
unifiedOfferConstraints.mandatory = unifiedOfferConstraints.mandatory || {};
unifiedOfferConstraints.mandatory.MozDontOfferDataChannel = true;
beOfferer = true;
}
if (window.webrtcDetectedBrowser === 'firefox' && window.webrtcDetectedVersion >= 32) {
unifiedOfferConstraints = {
offerToReceiveAudio: true,
offerToReceiveVideo: true
};
}
*/
// Fallback to use mandatory constraints for plugin based browsers
if (['IE', 'safari'].indexOf(window.webrtcDetectedBrowser) > -1) {
offerConstraints = {
mandatory: {
OfferToReceiveAudio: true,
OfferToReceiveVideo: true,
iceRestart: self._enableIceRestart && peerIceRestartSupport ? iceRestart === true : false
}
};
}
// Add stream only at offer/answer end
if (!self._hasMCU || targetMid === 'MCU') {
self._addLocalMediaStreams(targetMid);
}
if (self._enableDataChannel && self._peerInformations[targetMid] &&
self._peerInformations[targetMid].config.enableDataChannel) {
// Edge doesn't support datachannels yet
if (!(self._dataChannels[targetMid] && self._dataChannels[targetMid].main)) {
self._createDataChannel(targetMid);
self._peerConnections[targetMid].hasMainChannel = true;
}
}
log.debug([targetMid, null, null, 'Creating offer with config:'], offerConstraints);
pc.endOfCandidates = false;
pc.createOffer(function(offer) {
log.debug([targetMid, null, null, 'Created offer'], offer);
self._setLocalAndSendMessage(targetMid, offer);
}, function(error) {
self._trigger('handshakeProgress', self.HANDSHAKE_PROGRESS.ERROR, targetMid, error);
log.error([targetMid, null, null, 'Failed creating an offer:'], error);
}, offerConstraints);
};
/**
* Function that creates the Peer connection answer session description.
* This comes after receiving and setting the offer session description.
* @method _doAnswer
* @private
* @for Skylink
* @since 0.1.0
*/
Skylink.prototype._doAnswer = function(targetMid) {
var self = this;
log.log([targetMid, null, null, 'Creating answer with config:'],
self._room.connection.sdpConstraints);
var pc = self._peerConnections[targetMid];
// Added checks to ensure that connection object is defined first
if (!pc) {
log.warn([targetMid, 'RTCSessionDescription', 'answer', 'Dropping of creating of answer ' +
'as connection does not exists']);
return;
}
// Added checks to ensure that state is "have-remote-offer" if setting local "answer"
if (pc.signalingState !== self.PEER_CONNECTION_STATE.HAVE_REMOTE_OFFER) {
log.warn([targetMid, 'RTCSessionDescription', 'answer',
'Dropping of creating of answer as signalingState is not "' +
self.PEER_CONNECTION_STATE.HAVE_REMOTE_OFFER + '" ->'], pc.signalingState);
return;
}
// Add stream only at offer/answer end
if (!self._hasMCU || targetMid === 'MCU') {
self._addLocalMediaStreams(targetMid);
}
// No ICE restart constraints for createAnswer as it fails in chrome 48
// { iceRestart: true }
pc.createAnswer(function(answer) {
log.debug([targetMid, null, null, 'Created answer'], answer);
self._setLocalAndSendMessage(targetMid, answer);
}, function(error) {
log.error([targetMid, null, null, 'Failed creating an answer:'], error);
self._trigger('handshakeProgress', self.HANDSHAKE_PROGRESS.ERROR, targetMid, error);
});
};
/**
* Function that sets the local session description and sends to Peer.
* If trickle ICE is disabled, the local session description will be sent after
* ICE gathering has been completed.
* @method _setLocalAndSendMessage
* @private
* @for Skylink
* @since 0.5.2
*/
Skylink.prototype._setLocalAndSendMessage = function(targetMid, sessionDescription) {
var self = this;
var pc = self._peerConnections[targetMid];
// Added checks to ensure that sessionDescription is defined first
if (!(!!sessionDescription && !!sessionDescription.sdp)) {
log.warn([targetMid, 'RTCSessionDescription', null, 'Local session description is undefined ->'], sessionDescription);
return;
}
// Added checks to ensure that connection object is defined first
if (!pc) {
log.warn([targetMid, 'RTCSessionDescription', sessionDescription.type,
'Local session description will not be set as connection does not exists ->'], sessionDescription);
return;
} else if (sessionDescription.type === self.HANDSHAKE_PROGRESS.OFFER &&
pc.signalingState !== self.PEER_CONNECTION_STATE.STABLE) {
log.warn([targetMid, 'RTCSessionDescription', sessionDescription.type, 'Local session description ' +
'will not be set as signaling state is "' + pc.signalingState + '" ->'], sessionDescription);
return;
// Added checks to ensure that state is "have-remote-offer" if setting local "answer"
} else if (sessionDescription.type === self.HANDSHAKE_PROGRESS.ANSWER &&
pc.signalingState !== self.PEER_CONNECTION_STATE.HAVE_REMOTE_OFFER) {
log.warn([targetMid, 'RTCSessionDescription', sessionDescription.type, 'Local session description ' +
'will not be set as signaling state is "' + pc.signalingState + '" ->'], sessionDescription);
return;
// Added checks if there is a current local sessionDescription being processing before processing this one
} else if (pc.processingLocalSDP) {
log.warn([targetMid, 'RTCSessionDescription', sessionDescription.type,
'Local session description will not be set as another is being processed ->'], sessionDescription);
return;
}
pc.processingLocalSDP = true;
// Sets and expected receiving codecs etc.
//sessionDescription.sdp = self._setSDPOpusConfig(targetMid, sessionDescription);
//sessionDescription.sdp = self._setSDPCodec(targetMid, sessionDescription);
sessionDescription.sdp = self._removeSDPFirefoxH264Pref(targetMid, sessionDescription);
sessionDescription.sdp = self._removeSDPH264VP9AptRtxForOlderPlugin(targetMid, sessionDescription);
sessionDescription.sdp = self._removeSDPCodecs(targetMid, sessionDescription);
sessionDescription.sdp = self._handleSDPConnectionSettings(targetMid, sessionDescription);
//sessionDescription.sdp = self._setSDPBitrate(targetMid, sessionDescription);
sessionDescription.sdp = self._removeSDPREMBPackets(targetMid, sessionDescription);
log.log([targetMid, 'RTCSessionDescription', sessionDescription.type,
'Local session description updated ->'], sessionDescription.sdp);
pc.setLocalDescription(sessionDescription, function() {
log.debug([targetMid, 'RTCSessionDescription', sessionDescription.type,
'Local session description has been set ->'], sessionDescription);
pc.processingLocalSDP = false;
self._trigger('handshakeProgress', sessionDescription.type, targetMid);
if (sessionDescription.type === self.HANDSHAKE_PROGRESS.ANSWER) {
pc.setAnswer = 'local';
} else {
pc.setOffer = 'local';
}
if (!self._enableIceTrickle && !pc.gathered) {
log.log([targetMid, 'RTCSessionDescription', sessionDescription.type,
'Local session description sending is halted to complete ICE gathering.']);
return;
}
self._sendChannelMessage({
type: sessionDescription.type,
sdp: self._addSDPMediaStreamTrackIDs(targetMid, sessionDescription),
mid: self._user.sid,
target: targetMid,
rid: self._room.id,
userInfo: self._getUserInfo()
});
}, function(error) {
log.error([targetMid, 'RTCSessionDescription', sessionDescription.type, 'Local description failed setting ->'], error);
pc.processingLocalSDP = false;
self._trigger('handshakeProgress', self.HANDSHAKE_PROGRESS.ERROR, targetMid, error);
});
};