Solution for FirebaseRTC Codelab

public/app.js

@@ -1,6 +1,5 @@
 mdc.ripple.MDCRipple.attachTo(document.querySelector('.mdc-button'));
 
-// DEfault configuration - Change these if you have a different STUN or TURN server.
 const configuration = {
   iceServers: [
     {
@@ -42,11 +41,34 @@ async function createRoom() {
   });
 
   // Code for creating a room below
-
+  const offer = await peerConnection.createOffer();
+  await peerConnection.setLocalDescription(offer);
+  console.log('Created offer:', offer);
+
+  const roomWithOffer = {
+    'offer': {
+      type: offer.type,
+      sdp: offer.sdp,
+    },
+  };
+  const roomRef = await db.collection('rooms').add(roomWithOffer);
+  roomId = roomRef.id;
+  console.log(`New room created with SDP offer. Room ID: ${roomRef.id}`);
+  document.querySelector(
+      '#currentRoom').innerText = `Current room is ${roomRef.id} - You are the caller!`;
   // Code for creating a room above
 
   // Code for collecting ICE candidates below
-
+  const callerCandidatesCollection = roomRef.collection('callerCandidates');
+
+  peerConnection.addEventListener('icecandidate', event => {
+    if (!event.candidate) {
+      console.log('Got final candidate!');
+      return;
+    }
+    console.log('Got candidate: ', event.candidate);
+    callerCandidatesCollection.add(event.candidate.toJSON());
+  });
   // Code for collecting ICE candidates above
 
   peerConnection.addEventListener('track', event => {
@@ -58,11 +80,26 @@ async function createRoom() {
   });
 
   // Listening for remote session description below
-
+  roomRef.onSnapshot(async snapshot => {
+    const data = snapshot.data();
+    if (!peerConnection.currentRemoteDescription && data.answer) {
+      console.log('Got remote description: ', data.answer);
+      const rtcSessionDescription = new RTCSessionDescription(data.answer);
+      await peerConnection.setRemoteDescription(rtcSessionDescription);
+    }
+  });
   // Listening for remote session description above
 
   // Listen for remote ICE candidates below
-
+  roomRef.collection('calleeCandidates').onSnapshot(snapshot => {
+    snapshot.docChanges().forEach(async change => {
+      if (change.type === 'added') {
+        let data = change.doc.data();
+        console.log(`Got new remote ICE candidate: ${JSON.stringify(data)}`);
+        await peerConnection.addIceCandidate(new RTCIceCandidate(data));
+      }
+    });
+  });
   // Listen for remote ICE candidates above
 }
 
@@ -96,7 +133,15 @@ async function joinRoomById(roomId) {
     });
 
     // Code for collecting ICE candidates below
-
+    const calleeCandidatesCollection = roomRef.collection('calleeCandidates');
+    peerConnection.addEventListener('icecandidate', event => {
+      if (!event.candidate) {
+        console.log('Got final candidate!');
+        return;
+      }
+      console.log('Got candidate: ', event.candidate);
+      calleeCandidatesCollection.add(event.candidate.toJSON());
+    });
     // Code for collecting ICE candidates above
 
     peerConnection.addEventListener('track', event => {
@@ -108,11 +153,32 @@ async function joinRoomById(roomId) {
     });
 
     // Code for creating SDP answer below
-
+    const offer = roomSnapshot.data().offer;
+    console.log('Got offer:', offer);
+    await peerConnection.setRemoteDescription(new RTCSessionDescription(offer));
+    const answer = await peerConnection.createAnswer();
+    console.log('Created answer:', answer);
+    await peerConnection.setLocalDescription(answer);
+
+    const roomWithAnswer = {
+      answer: {
+        type: answer.type,
+        sdp: answer.sdp,
+      },
+    };
+    await roomRef.update(roomWithAnswer);
     // Code for creating SDP answer above
 
     // Listening for remote ICE candidates below
-
+    roomRef.collection('callerCandidates').onSnapshot(snapshot => {
+      snapshot.docChanges().forEach(async change => {
+        if (change.type === 'added') {
+          let data = change.doc.data();
+          console.log(`Got new remote ICE candidate: ${JSON.stringify(data)}`);
+          await peerConnection.addIceCandidate(new RTCIceCandidate(data));
+        }
+      });
+    });
     // Listening for remote ICE candidates above
   }
 }