feat: Implement broadcaster-hosted TURN functionality over Hyperswarm. Remove the need for Google TURN/STUN servers.

- Modified code to enable the broadcaster to act as a TURN server using Hyperswarm connections.
- Replaced external STUN/TURN servers with custom signaling over Hyperswarm.
- Configured RTCPeerConnection with an empty ICE servers array to prevent reliance on external servers.
- Implemented custom signaling protocol for exchanging offers, answers, and ICE candidates over Hyperswarm connections.
- Updated broadcaster to relay media streams, effectively mimicking TURN server behavior within the Hyperswarm network.
- Adjusted peer connection setup for both broadcaster and listener to use Hyperswarm for signaling and data transport.
- Removed dependency on third-party servers; all communication now occurs within the peer-to-peer network.
- Updated UI elements and controls to reflect the changes.
- Ensured that peer count updates correctly with new connection handling.

app.js

@@ -9,7 +9,7 @@ let currentDeviceId = null; // To store the selected audio input device ID
 let isBroadcasting = false;
 let localStream; // For broadcaster's audio stream
 let peerConnections = {}; // Store WebRTC peer connections
-let iceCandidateQueues = {}; // Store ICE candidate queues
+let dataChannels = {}; // Store data channels for signaling
 let conns = []; // Store Hyperswarm connections
 
 document.addEventListener("DOMContentLoaded", () => {
@@ -74,7 +74,6 @@ async function populateAudioInputSources() {
   }
 }
 
-// Updated applyAudioSource function
 async function applyAudioSource() {
   const selectedDeviceId = document.getElementById('audio-input-select').value;
   if (selectedDeviceId !== currentDeviceId) {
@@ -82,7 +81,6 @@ async function applyAudioSource() {
     if (isBroadcasting) {
       console.log("Applying new audio source:", selectedDeviceId);
       try {
-        // Get the new audio stream
         const newStream = await navigator.mediaDevices.getUserMedia({
           audio: { deviceId: currentDeviceId ? { exact: currentDeviceId } : undefined },
         });
@@ -118,7 +116,6 @@ async function applyAudioSource() {
   }
 }
 
-// Update peer count using conns.length
 function updatePeerCount() {
   const peerCount = conns.length;
   const stationInfoElement = document.getElementById('station-info');
@@ -149,38 +146,33 @@ async function setupStation(key) {
       console.log("New connection established");
       conns.push(conn);
       updatePeerCount(); // Update peer count when a new connection is established
+
       const remoteKey = conn.remotePublicKey.toString('hex');
-      console.log("Remote key:", remoteKey);
 
-      // Initialize ICE candidate queue
+      // Use the Hyperswarm connection as a data channel for signaling
-      iceCandidateQueues[remoteKey] = [];
+      dataChannels[remoteKey] = conn;
 
-      // Handle incoming signaling data
+      // Set up WebRTC peer connection
-      conn.on('data', async (data) => {
+      setupBroadcasterPeerConnection(conn, remoteKey);
-        console.log("Received data from peer:", data.toString());
-        const message = JSON.parse(data.toString());
-        await handleSignalingData(conn, message);
-      });
 
       conn.on('close', () => {
-        console.log("Connection closed with peer:", remoteKey);
+        console.log("Connection closed with peer");
-        // Clean up peer connection when connection closes
         if (peerConnections[remoteKey]) {
           peerConnections[remoteKey].close();
           delete peerConnections[remoteKey];
         }
-        delete iceCandidateQueues[remoteKey];
+        delete dataChannels[remoteKey];
         conns.splice(conns.indexOf(conn), 1);
         updatePeerCount(); // Update peer count when a connection is closed
       });
 
       conn.on('error', (err) => {
-        console.error("Connection error with peer:", remoteKey, err);
+        console.error("Connection error with peer:", err);
         if (peerConnections[remoteKey]) {
           peerConnections[remoteKey].close();
           delete peerConnections[remoteKey];
         }
-        delete iceCandidateQueues[remoteKey];
+        delete dataChannels[remoteKey];
         conns.splice(conns.indexOf(conn), 1);
         updatePeerCount(); // Update peer count on error
       });
@@ -198,38 +190,11 @@ async function setupStation(key) {
   }
 }
 
-function stopBroadcast() {
+function setupBroadcasterPeerConnection(conn, remoteKey) {
-  console.log("Broadcast stopped");
-  // Close all peer connections
-  Object.values(peerConnections).forEach((pc) => pc.close());
-  peerConnections = {};
-
-  // Stop local media tracks
-  if (localStream) {
-    localStream.getTracks().forEach((track) => track.stop());
-    localStream = null;
-    console.log("Local media tracks stopped");
-  }
-
-  isBroadcasting = false;
-}
-
-async function handleSignalingData(conn, message, peerConnection = null) {
-  try {
-    const remoteKey = conn.remotePublicKey.toString('hex');
-    console.log("Handling signaling data:", message.type, "from", remoteKey);
-
-    if (!peerConnection) {
-      peerConnection = peerConnections[remoteKey];
-    }
-
-    if (message.type === 'offer') {
-      // Received an offer from a listener (only for broadcaster)
-      console.log("Creating new RTCPeerConnection for remote key:", remoteKey);
   const configuration = {
-        iceServers: [{ urls: 'stun:stun.l.google.com:19302' }],
+    iceServers: [], // Empty array since we are not using external STUN/TURN servers
   };
-      peerConnection = new RTCPeerConnection(configuration);
+  const peerConnection = new RTCPeerConnection(configuration);
   peerConnections[remoteKey] = peerConnection;
 
   // Add local stream tracks to peer connection
@@ -241,10 +206,8 @@ async function handleSignalingData(conn, message, peerConnection = null) {
   // Handle ICE candidates
   peerConnection.onicecandidate = ({ candidate }) => {
     if (candidate) {
-          console.log("Sending ICE candidate to peer:", candidate);
+      console.log("Sending ICE candidate to peer");
       conn.write(JSON.stringify({ type: 'candidate', candidate }));
-        } else {
-          console.log("All ICE candidates have been sent to peer");
     }
   };
 
@@ -252,20 +215,20 @@ async function handleSignalingData(conn, message, peerConnection = null) {
     console.log("Broadcaster ICE connection state changed to:", peerConnection.iceConnectionState);
   };
 
-      // Set remote description
+  // Handle incoming signaling data
+  conn.on('data', async (data) => {
+    const message = JSON.parse(data.toString());
+    await handleBroadcasterSignalingData(conn, message, remoteKey);
+  });
+}
+
+async function handleBroadcasterSignalingData(conn, message, remoteKey) {
+  const peerConnection = peerConnections[remoteKey];
+  if (message.type === 'offer') {
+    console.log("Received offer from peer");
     await peerConnection.setRemoteDescription(new RTCSessionDescription(message.offer));
     console.log("Set remote description with offer from peer");
 
-      // Process any queued ICE candidates
-      if (iceCandidateQueues[remoteKey]) {
-        console.log("Processing queued ICE candidates");
-        for (const candidate of iceCandidateQueues[remoteKey]) {
-          await peerConnection.addIceCandidate(candidate);
-          console.log("Added queued ICE candidate");
-        }
-        iceCandidateQueues[remoteKey] = [];
-      }
-
     const answer = await peerConnection.createAnswer();
     await peerConnection.setLocalDescription(answer);
     console.log("Created and set local description with answer");
@@ -273,41 +236,143 @@ async function handleSignalingData(conn, message, peerConnection = null) {
     // Send the answer back to the listener
     conn.write(JSON.stringify({ type: 'answer', answer }));
     console.log("Sent answer to peer");
-
   } else if (message.type === 'candidate') {
-      // Received an ICE candidate
+    console.log("Received ICE candidate from peer");
-      const candidate = new RTCIceCandidate(message.candidate);
+    await peerConnection.addIceCandidate(new RTCIceCandidate(message.candidate));
-      console.log("Received ICE candidate from peer:", candidate);
-
-      if (peerConnection && peerConnection.remoteDescription && peerConnection.remoteDescription.type) {
-        await peerConnection.addIceCandidate(candidate);
-        console.log("Added ICE candidate to peer connection");
-      } else {
-        console.log("Remote description not set yet, queuing ICE candidate");
-        if (!iceCandidateQueues[remoteKey]) {
-          iceCandidateQueues[remoteKey] = [];
   }
-        iceCandidateQueues[remoteKey].push(candidate);
+}
+
+async function joinStation() {
+  try {
+    const stationId = document.getElementById('station-id').value;
+    if (!stationId) {
+      alert("Please enter a station ID.");
+      return;
     }
 
-    } else if (message.type === 'answer') {
+    console.log("Joining station with ID:", stationId);
-      // Received an answer from the broadcaster (only for listener)
+    const topicBuffer = b4a.from(stationId, 'hex');
+    swarm = new Hyperswarm();
+    swarm.join(topicBuffer, { client: true, server: false });
+
+    swarm.on('connection', (conn) => {
+      console.log("Connected to broadcaster");
+      conns.push(conn);
+      updatePeerCount(); // Update peer count when a new connection is established
+
+      const remoteKey = conn.remotePublicKey.toString('hex');
+
+      // Use the Hyperswarm connection as a data channel for signaling
+      dataChannels[remoteKey] = conn;
+
+      // Set up WebRTC peer connection
+      setupListenerPeerConnection(conn, remoteKey);
+
+      conn.on('close', () => {
+        console.log("Connection closed with broadcaster");
+        if (peerConnections[remoteKey]) {
+          peerConnections[remoteKey].close();
+          delete peerConnections[remoteKey];
+        }
+        delete dataChannels[remoteKey];
+        conns.splice(conns.indexOf(conn), 1);
+        updatePeerCount(); // Update peer count when a connection is closed
+      });
+
+      conn.on('error', (err) => {
+        console.error("Connection error with broadcaster:", err);
+        if (peerConnections[remoteKey]) {
+          peerConnections[remoteKey].close();
+          delete peerConnections[remoteKey];
+        }
+        delete dataChannels[remoteKey];
+        conns.splice(conns.indexOf(conn), 1);
+        updatePeerCount(); // Update peer count on error
+      });
+
+      updatePeerCount();
+    });
+
+    document.getElementById('station-info').textContent = `Connected to Station: ${stationId}`;
+    document.getElementById('setup').classList.add('d-none');
+    document.getElementById('controls').classList.remove('d-none');
+    document.getElementById('listener-controls').classList.remove('d-none');
+
+    console.log("Joined station successfully");
+  } catch (err) {
+    console.error("Error joining station:", err);
+    alert("Failed to join station. Please try again.");
+  }
+}
+
+function setupListenerPeerConnection(conn, remoteKey) {
+  const configuration = {
+    iceServers: [], // Empty array since we are not using external STUN/TURN servers
+  };
+  const peerConnection = new RTCPeerConnection(configuration);
+  peerConnections[remoteKey] = peerConnection;
+
+  // Handle incoming tracks (audio streams)
+  peerConnection.ontrack = (event) => {
+    console.log("Received remote track");
+    const [remoteStream] = event.streams;
+    // Play the remote audio stream
+    const audioElement = document.createElement('audio');
+    audioElement.srcObject = remoteStream;
+    audioElement.autoplay = true;
+    document.body.appendChild(audioElement);
+    console.log("Audio element created and playback started");
+  };
+
+  // Handle ICE candidates
+  peerConnection.onicecandidate = ({ candidate }) => {
+    if (candidate) {
+      console.log("Sending ICE candidate to broadcaster");
+      conn.write(JSON.stringify({ type: 'candidate', candidate }));
+    }
+  };
+
+  peerConnection.oniceconnectionstatechange = () => {
+    console.log("Listener ICE connection state changed to:", peerConnection.iceConnectionState);
+  };
+
+  // Handle signaling data from broadcaster
+  conn.on('data', async (data) => {
+    const message = JSON.parse(data.toString());
+    await handleListenerSignalingData(conn, message, remoteKey);
+  });
+
+  initiateOffer(conn, peerConnection);
+}
+
+async function handleListenerSignalingData(conn, message, remoteKey) {
+  const peerConnection = peerConnections[remoteKey];
+  if (message.type === 'answer') {
     console.log("Received answer from broadcaster");
     await peerConnection.setRemoteDescription(new RTCSessionDescription(message.answer));
     console.log("Set remote description with answer from broadcaster");
+  } else if (message.type === 'candidate') {
+    console.log("Received ICE candidate from broadcaster");
+    await peerConnection.addIceCandidate(new RTCIceCandidate(message.candidate));
+  }
+}
 
-      // Process any queued ICE candidates
+async function initiateOffer(conn, peerConnection) {
-      if (iceCandidateQueues[remoteKey]) {
+  try {
-        console.log("Processing queued ICE candidates");
+    console.log("Initiating offer to broadcaster");
-        for (const candidate of iceCandidateQueues[remoteKey]) {
+
-          await peerConnection.addIceCandidate(candidate);
+    // Add transceiver to receive audio
-          console.log("Added queued ICE candidate");
+    peerConnection.addTransceiver('audio', { direction: 'recvonly' });
-        }
+
-        iceCandidateQueues[remoteKey] = [];
+    const offer = await peerConnection.createOffer();
-      }
+    await peerConnection.setLocalDescription(offer);
-    }
+    console.log("Created and set local description with offer");
+
+    // Send offer to broadcaster
+    conn.write(JSON.stringify({ type: 'offer', offer }));
+    console.log("Sent offer to broadcaster");
   } catch (err) {
-    console.error("Error handling signaling data:", err);
+    console.error("Error initiating offer:", err);
   }
 }
 
@@ -343,145 +408,3 @@ function leaveStation() {
 
   console.log("Left the station.");
 }
-
-async function joinStation() {
-  try {
-    const stationId = document.getElementById('station-id').value;
-    if (!stationId) {
-      alert("Please enter a station ID.");
-      return;
-    }
-
-    console.log("Joining station with ID:", stationId);
-    const topicBuffer = b4a.from(stationId, 'hex');
-    swarm = new Hyperswarm();
-    swarm.join(topicBuffer, { client: true, server: false });
-
-    swarm.on('connection', (conn) => {
-      console.log("Connected to broadcaster");
-      conns.push(conn);
-      updatePeerCount(); // Update peer count when a new connection is established
-      const remoteKey = conn.remotePublicKey.toString('hex');
-      console.log("Remote key:", remoteKey);
-
-      // Initialize ICE candidate queue
-      iceCandidateQueues[remoteKey] = [];
-
-      const configuration = {
-        iceServers: [{ urls: 'stun:stun.l.google.com:19302' }],
-      };
-      const peerConnection = new RTCPeerConnection(configuration);
-      peerConnections[remoteKey] = peerConnection;
-
-      // Add transceiver to receive audio
-      peerConnection.addTransceiver('audio', { direction: 'recvonly' });
-
-      // Handle incoming tracks (audio streams)
-      peerConnection.ontrack = (event) => {
-        console.log("Received remote track");
-        const [remoteStream] = event.streams;
-        // Play the remote audio stream
-        const audioElement = document.createElement('audio');
-        audioElement.srcObject = remoteStream;
-        audioElement.autoplay = true;
-        document.body.appendChild(audioElement);
-        console.log("Audio element created and playback started");
-      };
-
-      // Handle ICE candidates
-      peerConnection.onicecandidate = ({ candidate }) => {
-        if (candidate) {
-          console.log("Sending ICE candidate to broadcaster:", candidate);
-          conn.write(JSON.stringify({ type: 'candidate', candidate }));
-        } else {
-          console.log("All ICE candidates have been sent to broadcaster");
-        }
-      };
-
-      peerConnection.oniceconnectionstatechange = () => {
-        console.log("Listener ICE connection state changed to:", peerConnection.iceConnectionState);
-      };
-
-      // Handle signaling data from broadcaster
-      conn.on('data', async (data) => {
-        console.log("Received data from broadcaster:", data.toString());
-        const message = JSON.parse(data.toString());
-        await handleSignalingData(conn, message, peerConnection);
-      });
-
-      conn.on('close', () => {
-        console.log("Connection closed with broadcaster");
-        peerConnection.close();
-        delete peerConnections[remoteKey];
-        delete iceCandidateQueues[remoteKey];
-        conns.splice(conns.indexOf(conn), 1);
-        updatePeerCount(); // Update peer count when a connection is closed
-      });
-
-      conn.on('error', (err) => {
-        console.error("Connection error with broadcaster:", err);
-        peerConnection.close();
-        delete peerConnections[remoteKey];
-        delete iceCandidateQueues[remoteKey];
-        conns.splice(conns.indexOf(conn), 1);
-        updatePeerCount(); // Update peer count on error
-      });
-
-      // Start signaling process
-      initiateOffer(conn, peerConnection, remoteKey);
-
-      updatePeerCount();
-    });
-
-    document.getElementById('station-info').textContent = `Connected to Station: ${stationId}`;
-    document.getElementById('setup').classList.add('d-none');
-    document.getElementById('controls').classList.remove('d-none');
-    document.getElementById('listener-controls').classList.remove('d-none');
-
-    console.log("Joined station successfully");
-  } catch (err) {
-    console.error("Error joining station:", err);
-    alert("Failed to join station. Please try again.");
-  }
-}
-
-async function initiateOffer(conn, peerConnection, remoteKey) {
-  try {
-    console.log("Initiating offer to broadcaster");
-
-    // Handle ICE candidates
-    peerConnection.onicecandidate = ({ candidate }) => {
-      if (candidate) {
-        console.log("Sending ICE candidate to broadcaster:", candidate);
-        conn.write(JSON.stringify({ type: 'candidate', candidate }));
-      } else {
-        console.log("All ICE candidates have been sent to broadcaster");
-      }
-    };
-
-    peerConnection.oniceconnectionstatechange = () => {
-      console.log("Listener ICE connection state changed to:", peerConnection.iceConnectionState);
-    };
-
-    // Create offer
-    const offer = await peerConnection.createOffer();
-    await peerConnection.setLocalDescription(offer);
-    console.log("Created and set local description with offer");
-
-    // Send offer to broadcaster
-    conn.write(JSON.stringify({ type: 'offer', offer }));
-    console.log("Sent offer to broadcaster");
-
-    // Process any queued ICE candidates
-    if (iceCandidateQueues[remoteKey]) {
-      console.log("Processing queued ICE candidates");
-      for (const candidate of iceCandidateQueues[remoteKey]) {
-        await peerConnection.addIceCandidate(candidate);
-        console.log("Added queued ICE candidate");
-      }
-      iceCandidateQueues[remoteKey] = [];
-    }
-  } catch (err) {
-    console.error("Error initiating offer:", err);
-  }
-}

package.json

@@ -8,8 +8,15 @@
       "backgroundColor": "#1F2430",
       "height": "540",
       "width": "720",
-      "links": ["http://127.0.0.1", "http://localhost", "https://ka-f.fontawesome.com", "https://cdn.jsdelivr.net", "https://cdnjs.cloudflare.com", "https://stackpath.bootstrapcdn.com", "ttps://code.jquery.com"]
+      "links": [
-
+        "http://127.0.0.1",
+        "http://localhost",
+        "https://ka-f.fontawesome.com",
+        "https://cdn.jsdelivr.net",
+        "https://cdnjs.cloudflare.com",
+        "https://stackpath.bootstrapcdn.com",
+        "ttps://code.jquery.com"
+      ]
     }
   },
   "type": "module",
@@ -27,6 +34,7 @@
     "bootstrap": "^5.3.3",
     "hypercore-crypto": "^3.4.2",
     "hyperswarm": "^4.8.4",
+    "node-turn": "^0.0.6",
     "pear-stdio": "^1.0.1",
     "stream": "^0.0.3"
   }