File: source/peer-handshake.js

  1. /**
  2.  * Function that creates the Peer connection offer session description.
  3.  * @method _doOffer
  4.  * @private
  5.  * @for Skylink
  6.  * @since 0.5.2
  7.  */
  8. Skylink.prototype._doOffer = function(targetMid, iceRestart, mergeMessageWithOffer) {
  9.   var self = this;
  10.   var pc = self._peerConnections[targetMid];
  11.  
  12.   // Added checks to ensure that connection object is defined first
  13.   if (!pc) {
  14.     log.warn([targetMid, 'RTCSessionDescription', 'offer', 'Dropping of creating of offer ' +
  15.       'as connection does not exists']);
  16.     return;
  17.   }
  18.  
  19.   // Added checks to ensure that state is "stable" if setting local "offer"
  20.   if (pc.signalingState !== self.PEER_CONNECTION_STATE.STABLE) {
  21.     log.warn([targetMid, 'RTCSessionDescription', 'offer',
  22.       'Dropping of creating of offer as signalingState is not "' +
  23.       self.PEER_CONNECTION_STATE.STABLE + '" ->'], pc.signalingState);
  24.     return;
  25.   }
  26.  
  27.   var offerConstraints = {
  28.     offerToReceiveAudio: !(!self._sdpSettings.connection.audio && targetMid !== 'MCU') && self._getSDPCommonSupports(targetMid).video,
  29.     offerToReceiveVideo: !(!self._sdpSettings.connection.video && targetMid !== 'MCU') && self._getSDPCommonSupports(targetMid).audio,
  30.     iceRestart: !!((self._peerInformations[targetMid] || {}).config || {}).enableIceRestart &&
  31.       iceRestart && self._enableIceRestart,
  32.     voiceActivityDetection: self._voiceActivityDetection
  33.   };
  34.  
  35.   // Add stream only at offer/answer end
  36.   if (!self._hasMCU || targetMid === 'MCU') {
  37.     //self._compareTrackCounts(targetMid);
  38.     self._addLocalMediaStreams(targetMid);
  39.   }
  40.  
  41.   if (self._initOptions.enableDataChannel && self._peerInformations[targetMid] &&
  42.     self._peerInformations[targetMid].config.enableDataChannel/* &&
  43.     !(!self._sdpSettings.connection.data && targetMid !== 'MCU')*/) {
  44.     // Edge doesn't support datachannels yet
  45.     if (!(self._dataChannels[targetMid] && self._dataChannels[targetMid].main)) {
  46.       self._createDataChannel(targetMid);
  47.       self._peerConnections[targetMid].hasMainChannel = true;
  48.     }
  49.   }
  50.  
  51.   log.debug([targetMid, null, null, 'Creating offer with config:'], offerConstraints);
  52.  
  53.   pc.endOfCandidates = false;
  54.  
  55.   if (self._peerConnStatus[targetMid]) {
  56.     self._peerConnStatus[targetMid].sdpConstraints = offerConstraints;
  57.   }
  58.  
  59.   var onSuccessCbFn = function(offer) {
  60.     log.debug([targetMid, null, null, 'Created offer'], offer);
  61.     self._handleNegotiationStats('create_offer', targetMid, offer, false);
  62.     self._setLocalAndSendMessage(targetMid, offer, mergeMessageWithOffer);
  63.   };
  64.  
  65.   var onErrorCbFn = function(error) {
  66.     log.error([targetMid, null, null, 'Failed creating an offer:'], error);
  67.     self._handleNegotiationStats('error_create_offer', targetMid, null, false, error);
  68.     self._trigger('handshakeProgress', self.HANDSHAKE_PROGRESS.ERROR, targetMid, error);
  69.   };
  70.  
  71.   pc.createOffer(onSuccessCbFn, onErrorCbFn, AdapterJS.webrtcDetectedType === 'plugin' ? {
  72.     mandatory: {
  73.       OfferToReceiveAudio: offerConstraints.offerToReceiveAudio,
  74.       OfferToReceiveVideo: offerConstraints.offerToReceiveVideo,
  75.       iceRestart: offerConstraints.iceRestart,
  76.       voiceActivityDetection: offerConstraints.voiceActivityDetection
  77.     }
  78.   } : offerConstraints);
  79. };
  80.  
  81. /**
  82.  * Function that creates the Peer connection answer session description.
  83.  * This comes after receiving and setting the offer session description.
  84.  * @method _doAnswer
  85.  * @private
  86.  * @for Skylink
  87.  * @since 0.1.0
  88.  */
  89. Skylink.prototype._doAnswer = function(targetMid) {
  90.   var self = this;
  91.   log.log([targetMid, null, null, 'Creating answer with config:'],
  92.     self._room.connection.sdpConstraints);
  93.   var pc = self._peerConnections[targetMid];
  94.  
  95.   // Added checks to ensure that connection object is defined first
  96.   if (!pc) {
  97.     log.warn([targetMid, 'RTCSessionDescription', 'answer', 'Dropping of creating of answer ' +
  98.       'as connection does not exists']);
  99.     return;
  100.   }
  101.  
  102.   // Added checks to ensure that state is "have-remote-offer" if setting local "answer"
  103.   if (pc.signalingState !== self.PEER_CONNECTION_STATE.HAVE_REMOTE_OFFER) {
  104.     log.warn([targetMid, 'RTCSessionDescription', 'answer',
  105.       'Dropping of creating of answer as signalingState is not "' +
  106.       self.PEER_CONNECTION_STATE.HAVE_REMOTE_OFFER + '" ->'], pc.signalingState);
  107.     return;
  108.   }
  109.  
  110.   var answerConstraints = AdapterJS.webrtcDetectedBrowser === 'edge' ? {
  111.     offerToReceiveVideo: !(!self._sdpSettings.connection.audio && targetMid !== 'MCU') &&
  112.       self._getSDPCommonSupports(targetMid, pc.remoteDescription).video,
  113.     offerToReceiveAudio: !(!self._sdpSettings.connection.video && targetMid !== 'MCU') &&
  114.       self._getSDPCommonSupports(targetMid, pc.remoteDescription).audio,
  115.     voiceActivityDetection: self._voiceActivityDetection
  116.   } : undefined;
  117.  
  118.   // Add stream only at offer/answer end
  119.   if (!self._hasMCU || targetMid === 'MCU') {
  120.     self._addLocalMediaStreams(targetMid);
  121.   }
  122.  
  123.   if (self._peerConnStatus[targetMid]) {
  124.     self._peerConnStatus[targetMid].sdpConstraints = answerConstraints;
  125.   }
  126.  
  127.   var onSuccessCbFn = function(answer) {
  128.     log.debug([targetMid, null, null, 'Created answer'], answer);
  129.     self._handleNegotiationStats('create_answer', targetMid, answer, false);
  130.  
  131.     if (AdapterJS.webrtcDetectedBrowser === 'firefox') {
  132.       self._setOriginalDTLSRole(answer, false);
  133.       answer.sdp = self._modifyDTLSRole(answer);
  134.     }
  135.  
  136.     self._setLocalAndSendMessage(targetMid, answer);
  137.   };
  138.  
  139.   var onErrorCbFn = function(error) {
  140.     log.error([targetMid, null, null, 'Failed creating an answer:'], error);
  141.     self._handleNegotiationStats('error_create_answer', targetMid, null, false, error);
  142.     self._trigger('handshakeProgress', self.HANDSHAKE_PROGRESS.ERROR, targetMid, error);
  143.   };
  144.  
  145.   // No ICE restart constraints for createAnswer as it fails in chrome 48
  146.   // { iceRestart: true }
  147.   pc.createAnswer(onSuccessCbFn, onErrorCbFn, answerConstraints);
  148. };
  149.  
  150. /**
  151.  * Function that sets the local session description and sends to Peer.
  152.  * If trickle ICE is disabled, the local session description will be sent after
  153.  *   ICE gathering has been completed.
  154.  * @method _setLocalAndSendMessage
  155.  * @private
  156.  * @for Skylink
  157.  * @since 0.5.2
  158.  */
  159. Skylink.prototype._setLocalAndSendMessage = function(targetMid, _sessionDescription, mergeMessage) {
  160.   var self = this;
  161.   var pc = self._peerConnections[targetMid];
  162.  
  163.   // Added checks to ensure that sessionDescription is defined first
  164.   if (!(!!_sessionDescription && !!_sessionDescription.sdp)) {
  165.     log.warn([targetMid, 'RTCSessionDescription', null, 'Local session description is undefined ->'], _sessionDescription);
  166.     return;
  167.   }
  168.  
  169.   // Added checks to ensure that connection object is defined first
  170.   if (!pc) {
  171.     log.warn([targetMid, 'RTCSessionDescription', _sessionDescription.type,
  172.       'Local session description will not be set as connection does not exists ->'], _sessionDescription);
  173.     self._handleNegotiationStats('dropped_' + sessionDescription.type, targetMid, sessionDescription, false, 'Peer connection does not exists');
  174.     return;
  175.  
  176.   } else if (_sessionDescription.type === self.HANDSHAKE_PROGRESS.OFFER &&
  177.     pc.signalingState !== self.PEER_CONNECTION_STATE.STABLE) {
  178.     log.warn([targetMid, 'RTCSessionDescription', _sessionDescription.type, 'Local session description ' +
  179.       'will not be set as signaling state is "' + pc.signalingState + '" ->'], _sessionDescription);
  180.     self._handleNegotiationStats('dropped_offer', targetMid, sessionDescription, false, 'Peer connection state is "' + pc.signalingState + '"');
  181.     return;
  182.  
  183.   // Added checks to ensure that state is "have-remote-offer" if setting local "answer"
  184.   } else if (_sessionDescription.type === self.HANDSHAKE_PROGRESS.ANSWER &&
  185.     pc.signalingState !== self.PEER_CONNECTION_STATE.HAVE_REMOTE_OFFER) {
  186.     log.warn([targetMid, 'RTCSessionDescription', _sessionDescription.type, 'Local session description ' +
  187.       'will not be set as signaling state is "' + pc.signalingState + '" ->'], _sessionDescription);
  188.     self._handleNegotiationStats('dropped_answer', targetMid, sessionDescription, false, 'Peer connection state is "' + pc.signalingState + '"');
  189.     return;
  190.  
  191.   // Added checks if there is a current local sessionDescription being processing before processing this one
  192.   } else if (pc.processingLocalSDP) {
  193.     log.warn([targetMid, 'RTCSessionDescription', _sessionDescription.type,
  194.       'Local session description will not be set as another is being processed ->'], _sessionDescription);
  195.     self._handleNegotiationStats('dropped_' + sessionDescription.type, targetMid, sessionDescription, false, 'Peer connection is currently processing an existing sdp');
  196.     return;
  197.   }
  198.  
  199.   pc.processingLocalSDP = true;
  200.  
  201.   // Sets and expected receiving codecs etc.
  202.   var sessionDescription = {
  203.     type: _sessionDescription.type,
  204.     sdp: _sessionDescription.sdp
  205.   };
  206.  
  207.   sessionDescription.sdp = self._removeSDPFirefoxH264Pref(targetMid, sessionDescription);
  208.   sessionDescription.sdp = self._setSDPCodecParams(targetMid, sessionDescription);
  209.   sessionDescription.sdp = self._removeSDPUnknownAptRtx(targetMid, sessionDescription);
  210.   sessionDescription.sdp = self._removeSDPCodecs(targetMid, sessionDescription);
  211.   sessionDescription.sdp = self._handleSDPConnectionSettings(targetMid, sessionDescription, 'local');
  212.   sessionDescription.sdp = self._removeSDPREMBPackets(targetMid, sessionDescription);
  213.   sessionDescription.sdp = self._setSCTPport(targetMid, sessionDescription);
  214.  
  215.   if (self._peerConnectionConfig.disableBundle) {
  216.     sessionDescription.sdp = sessionDescription.sdp.replace(/a=group:BUNDLE.*\r\n/gi, '');
  217.   }
  218.  
  219.   log.log([targetMid, 'RTCSessionDescription', sessionDescription.type,
  220.     'Local session description updated ->'], sessionDescription.sdp);
  221.  
  222.   var onSuccessCbFn = function() {
  223.     log.debug([targetMid, 'RTCSessionDescription', sessionDescription.type,
  224.       'Local session description has been set ->'], sessionDescription);
  225.  
  226.     pc.processingLocalSDP = false;
  227.  
  228.     self._handleNegotiationStats('set_' + sessionDescription.type, targetMid, sessionDescription, false);
  229.     self._trigger('handshakeProgress', sessionDescription.type, targetMid);
  230.  
  231.     if (sessionDescription.type === self.HANDSHAKE_PROGRESS.ANSWER) {
  232.       pc.setAnswer = 'local';
  233.     } else {
  234.       pc.setOffer = 'local';
  235.     }
  236.  
  237.     if (!self._initOptions.enableIceTrickle && !pc.gathered) {
  238.       log.log([targetMid, 'RTCSessionDescription', sessionDescription.type,
  239.         'Local session description sending is halted to complete ICE gathering.']);
  240.       return;
  241.     }
  242.  
  243.     var messageToSend = {
  244.       type: sessionDescription.type,
  245.       sdp: sessionDescription.sdp,
  246.       mid: self._user.sid,
  247.       target: targetMid,
  248.       rid: self._room.id,
  249.       userInfo: self._getUserInfo(targetMid)
  250.     };
  251.  
  252.     // Merging Restart and Offer messages. The already present keys in offer message will not be overwritten.
  253.     // Only news keys from mergeMessage are added.
  254.     if (mergeMessage && Object.keys(mergeMessage).length) {
  255.       var keys = Object.keys(mergeMessage);
  256.       var currentMessageKeys = Object.keys(messageToSend);
  257.       for (var keyIndex = 0; keyIndex < keys.length; keyIndex++) {
  258.         var key = keys[keyIndex];
  259.         if (currentMessageKeys.indexOf(key) === -1) {
  260.           messageToSend[key] = mergeMessage[key];
  261.         }
  262.       }
  263.     }
  264.  
  265.     self._sendChannelMessage(messageToSend);
  266.     self._handleNegotiationStats(sessionDescription.type, targetMid, sessionDescription, false);
  267.   };
  268.  
  269.   var onErrorCbFn = function(error) {
  270.     log.error([targetMid, 'RTCSessionDescription', sessionDescription.type, 'Local description failed setting ->'], error);
  271.  
  272.     pc.processingLocalSDP = false;
  273.  
  274.     self._handleNegotiationStats('error_set_' + sessionDescription.type, targetMid, sessionDescription, false, error);
  275.     self._trigger('handshakeProgress', self.HANDSHAKE_PROGRESS.ERROR, targetMid, error);
  276.   };
  277.  
  278.   pc.setLocalDescription(new RTCSessionDescription(sessionDescription), onSuccessCbFn, onErrorCbFn);
  279. };
  280.  
  281.