Implemented WebRTC peer-to-peer screen-roadcasting

config.example.json

@@ -36,7 +36,7 @@
     },
     "iceServers":[
         {
-            "url":"stun:stun.moonlight-stream.org:3478"
+            "urls":["stun:stun.moonlight-stream.org:3478"]
         }
     ],
     "links":{

config.example.jsonc

@@ -68,7 +68,7 @@
     //Privdes STUN/TURN servers for WebRTC functionality
     "iceServers":[
         {
-            "url":"stun:stun.moonlight-stream.org:3478"
+            "urls":["stun:stun.moonlight-stream.org:3478"]
         }
     ],
     //Provides customizable links for navbar

www/js/channel/mediaHandler.js

@@ -944,6 +944,7 @@ class WebRTCLivestreamHandler extends rawFileBase{
         //Call derived constructor
         super(client, player, media, "webrtc");
 
+        //Define RTCHandler related listeners
         this.defineListeners();
     }
 
@@ -968,18 +969,22 @@ class WebRTCLivestreamHandler extends rawFileBase{
         };
 
         //If we're not streaming
-        if(!this.client.webRTCHandler.isStreaming){
+        if(!this.client.webRTCHandler.isBroadcasting){
             //Send stream request
             await this.client.webRTCHandler.requestStream();
+        //otherwise
+        }else{
+            //Load broadcasting stream into the player for local playback
+            this.startStream(this.client.webRTCHandler.broadcastingStream);
         }
     }
 
-    start(){
+    startStream(stream){
-        //call derived start function
+        //Set video source object to stream
-        super.start();        
+        this.video.srcObject = stream;
 
-        //Lock the player
+        //Autoplay Stream
-        this.setPlayerLock(true);
+        this.video.play();
     }
 
     setVideoTitle(title){
@@ -996,4 +1001,12 @@ class WebRTCLivestreamHandler extends rawFileBase{
         //Inject glowspan into title in a way that allows it to be easily replaced
         this.player.title.prepend(glowSpan);
     }
+
+    end(){
+        //Let the webRTC handler know the stream ended
+        this.client.webRTCHandler.end();
+
+        //Call derived method
+        super.end();
+    }
 }

www/js/channel/panels/queuePanel/queuePanel.js

@@ -309,9 +309,11 @@ class queuePanel extends panelObj{
     async goLive(event){
         //If we're broadcastinv via webrtc
         if(this.client.streamType == "webrtc"){
-            this.client.webRTCHandler.isBroadcasting = true;
+            await this.client.webRTCHandler.startStream();
 
-            this.client.webRTCHandler.broadcastingStream = await navigator.mediaDevices.getDisplayMedia();
+            //this.client.webRTCHandler.isBroadcasting = true;
+
+            //this.client.webRTCHandler.broadcastingStream = await navigator.mediaDevices.getDisplayMedia();
        }
 
         //Start a livestream

www/js/channel/webRTCHandler.js

@@ -33,6 +33,16 @@ class webRTCHandler{
          */
         this.isBroadcasting = false;
 
+        /**
+         * Flag thrown when a request to view a stream is answered
+         */
+        this.answered = false;
+
+        /**
+         * Create variable to hold Internet Connectivity Establishment configuration
+         */
+        this.iceConfig;
+
         /**
          * Create variable to hold the peer connection object for the currently playing remote stream 
          */
@@ -49,9 +59,9 @@ class webRTCHandler{
         this.currentViewers = new Map();
 
         /**
-         * Create variable to hold Internet Connectivity Establishment configuration
+         * Create array to hold candidates cached before 
          */
-        this.iceConfig;
+        this.cachedCandidates = [];
 
         //Call setup functions
         this.setupInput();
@@ -71,6 +81,29 @@ class webRTCHandler{
         this.client.socket.on("RTCData", this.handleRTCData.bind(this));
     }
 
+    async startStream(){
+        //Throw broadcasting flag
+        this.isBroadcasting = true;
+
+        //Get media stream from browser input
+        this.broadcastingStream = await navigator.mediaDevices.getDisplayMedia({
+            video: true,
+            audio: true
+        });
+
+        //If we didn't get any audio tracks from the DisplayMedia portion of the API
+        if(this.broadcastingStream == null || this.broadcastingStream.getAudioTracks().length == 0){
+            //Bug user for an audio device
+            const tempStream = await navigator.mediaDevices.getUserMedia({video: false, audio: true});
+
+            //For each track received from audio device
+            for(const track of tempStream.getAudioTracks()){
+                //Add to existing broadcast stream
+                this.broadcastingStream.addTrack(track);
+            }
+        }
+    }
+
     /**
      * Handles and routes incoming RTC Messages
      * Normally I'd use dedicated socket.io message types, however throwing user input seems like bad security practice
@@ -113,14 +146,15 @@ class webRTCHandler{
         //Create new peer connection w/ provided ice config
         this.currentStream = new RTCPeerConnection(this.iceConfig)
 
-        //Not really used atm but it's necissary for most browsers to need either a data channel or media track
+        //Setup peer event handlers
-        //addeed to the requesting peer before they start pulling ICE candidates...
-        this.currentStream.createDataChannel("aux");
-
         this.currentStream.addEventListener('icecandidate', this.sendIceCandidate.bind(this));
+        this.currentStream.addEventListener('track', this.handleVideoStream.bind(this));
 
         //Create offer from peerConnection
-        const offer = await this.currentStream.createOffer();
+        const offer = await this.currentStream.createOffer({
+            offerToReceiveAudio: true,
+            offerToReceiveVideo: true
+        });
 
         //Set offer as peerConnections local description
         await this.currentStream.setLocalDescription(offer);
@@ -161,18 +195,35 @@ class webRTCHandler{
         //Get answer from received data
         const answer = new RTCSessionDescription(data.body);
 
+        //Throw answered flag
+        this.answered = true;
+
+        //for each cached ICE candidate
+        for(const candidate of this.cachedCandidates){
+            //Send cached candidate, handing candidate to method packed in a phoney event object 
+            this.sendIceCandidate({candidate});
+        }
+
         //Set remote desription
         this.currentStream.setRemoteDescription(answer);
+
     }
 
     sendIceCandidate(event){
         //If we have a candidate
         if(event.candidate != null){
+            //If our stream request was answered
+            if(this.answered){
                 //Send that shit off!
                 this.client.socket.emit('relayRTCData',{
                     type: 'candidate',
                     body: event.candidate
                 });
+            //Otherwise
+            }else{
+                //Cache candidate
+                this.cachedCandidates.push(event.candidate);
+            }
         }
     }
 
@@ -186,10 +237,34 @@ class webRTCHandler{
             this.currentStream.addIceCandidate(data.body);
         }
     }
+
+    async handleVideoStream(event){
+        //If we where given a media stream
+        if(event.streams != null && event.streams[0] != null){
+            //hand it over to our player
+            this.client.player.mediaHandler.startStream(event.streams[0]);
+        }
+    }
+
+    end(){
+        //Drop flags
+        this.isBroadcasting = false;
+        this.answered = false;
+
+        //clear peer/media stream objects
+        this.currentStream = null;
+        this.broadcastingStream = null;
+
+        //clear currentViewers map
+        this.currentViewers.clear();
+
+        //Clear candidate cache
+        this.cachedCandidates = [];
+    }
 }
 
 /**
- * Class representing a single connected viewer
+ * Class representing a single connected remote viewer
  */
 class connectedViewer{
     constructor(user, socket, offer, broadcastingStream, iceConfig, client){
@@ -214,7 +289,7 @@ class connectedViewer{
         this.iceConfig = iceConfig;
         
         /**
-         * Client channe object
+         * Client channel object
          */
         this.client = client;
 
@@ -226,12 +301,12 @@ class connectedViewer{
         //Create peer from iceConfig
         const peer = new RTCPeerConnection(this.iceConfig);
 
+        //For every track from the local stream
         for(const track of this.broadcastingStream.getTracks()){
+            //Add it to the list of available tracks for our peer
             peer.addTrack(track, this.broadcastingStream);
         }
 
-        peer.addEventListener('icecandidate', this.sendIceCandidate.bind(this));
-
         //Set peer remote description to connection offer from viewer
         peer.setRemoteDescription(new RTCSessionDescription(offer));
 
@@ -241,6 +316,9 @@ class connectedViewer{
         //Set answer as local description
         await peer.setLocalDescription(answer);
 
+        //Setup peer ICE Candidate event listner
+        peer.addEventListener('icecandidate', this.sendIceCandidate.bind(this));
+
         //Save peer by socket identifier
         this.peers.set(socket, peer);
 
@@ -265,9 +343,7 @@ class connectedViewer{
     }
 
     handleIceCandidate(data){
-        console.log(this);
         const peer = this.peers.get(data.source.socket);
-        console.log(peer);
         peer.addIceCandidate(data.body);
 
         //Save peer by socket identifier