Tweak broadcaster example

Author: markandrus

README.md

@@ -16,7 +16,7 @@ This project presents a few example applications using node-webrtc.
   [node-canvas](https://github.com/Automattic/node-canvas), and RTCVideoSource
   to draw spinning text on top of an incoming video.
 - [Stream recording](examples/stream-record) using ffmpeg and RTCVideoSink
-- SFU example with one [broadcaster](examples/sfu-broadcast) which forward stream to many [clients](examples/sfu-watch)
+- Broadcast example with one ["broadcaster"](examples/broadcaster) forwarding to many ["viewers"](examples/viewers)
 
 Usage
 -----

examples/sfu-broadcast/client.js examples/broadcaster/client.jsexamples/sfu-broadcast/client.js renamed to examples/broadcaster/client.js

@@ -2,8 +2,10 @@
 
 const createExample = require('../../lib/browser/example');
 
-const description = 'Example of <a href="https://webrtcglossary.com/sfu/" target="_blank">SFU</a> <br/><br/>\
-Start broadcast and then your stream will be forward using  RTCAudioSink, RTCVideoSink, RTCAudioSource, RTCVideoSource';
+const description = 'Start a broadcast. Your stream will be forwarded to \
+multiple "watchers". Although you can prototype such a system with \
+node-webrtc, you should consider using an \
+<a href="https://webrtcglossary.com/sfu/" target="_blank">SFU</a>.';
 
 const localVideo = document.createElement('video');
 localVideo.autoplay = true;
@@ -32,7 +34,7 @@ async function beforeAnswer(peerConnection) {
   };
 }
 
-createExample('sfu-broadcast', description, { beforeAnswer });
+createExample('broadcaster', description, { beforeAnswer });
 
 const videos = document.createElement('div');
 videos.className = 'grid';

examples/broadcaster/server.js

@@ -0,0 +1,28 @@
+'use strict';
+
+const { EventEmitter } = require('events');
+
+const broadcaster = new EventEmitter();
+const { on } = broadcaster;
+
+function beforeOffer(peerConnection) {
+  const audioTrack = broadcaster.audioTrack = peerConnection.addTransceiver('audio').receiver.track;
+  const videoTrack = broadcaster.videoTrack = peerConnection.addTransceiver('video').receiver.track;
+
+  broadcaster.emit('newBroadcast', {
+    audioTrack,
+    videoTrack
+  });
+
+  const { close } = peerConnection;
+  peerConnection.close = function() {
+    audioTrack.stop()
+    videoTrack.stop()
+    return close.apply(this, arguments);
+  };
+}
+
+module.exports = { 
+  beforeOffer,
+  broadcaster
+};

examples/sfu-broadcast/server.js

@@ -2,8 +2,10 @@
 
 const createExample = require('../../lib/browser/example');
 
-const description = 'Example of <a href="https://webrtcglossary.com/sfu/" target="_blank">SFU</a> <br/><br/>\
-Start receive sfu-broadcaster stream.';
+const description = 'Watch a broadcast. You should have already started the \
+broadcast example. Although you can prototype such a system with  node-webrtc, \
+you should consider using an \
+<a href="https://webrtcglossary.com/sfu/" target="_blank">SFU</a>.';
 
 const remoteVideo = document.createElement('video');
 remoteVideo.autoplay = true;
@@ -22,7 +24,7 @@ async function beforeAnswer(peerConnection) {
   };
 }
 
-createExample('sfu-watch', description, { beforeAnswer });
+createExample('viewer', description, { beforeAnswer });
 
 const videos = document.createElement('div');
 videos.className = 'grid';

examples/sfu-watch/client.js examples/viewer/client.jsexamples/sfu-watch/client.js renamed to examples/viewer/client.js

@@ -1,21 +1,25 @@
 'use strict';
 
-const { event } = require('../sfu-broadcast/server')
+const { broadcaster } = require('../broadcaster/server')
 
 function beforeOffer(peerConnection) {
   const audioTransceiver = peerConnection.addTransceiver('audio');
   const videoTransceiver = peerConnection.addTransceiver('video');
 
-  const onNewBroadcast = ({ audioTrack, videoTrack })=>{
+  function onNewBroadcast({ audioTrack, videoTrack }) {
     audioTransceiver.sender.replaceTrack(audioTrack),
     videoTransceiver.sender.replaceTrack(videoTrack) 
-  };
+  }
+
+  broadcaster.on('newBroadcast', onNewBroadcast)
 
-  event.on('newBroadcast', onNewBroadcast)
+  if (broadcaster.audioTrack && broadcaster.videoTrack) {
+    onNewBroadcast(broadcaster);
+  }
 
   const { close } = peerConnection;
   peerConnection.close = function() {
-    event.removeListener('newBroadcast', onNewBroadcast);
+    broadcaster.removeListener('newBroadcast', onNewBroadcast);
     return close.apply(this, arguments);
   }
 }

examples/sfu-watch/server.js examples/viewer/server.jsexamples/sfu-watch/server.js renamed to examples/viewer/server.js

@@ -48,5 +48,5 @@ <h1>node-webrtc examples</h1>
   <li><a href="/sine-wave-stereo/index.html">sine-wave-stereo
   <li><a href="/video-compositing/index.html">video-compositing
   <li><a href="/stream-record/index.html">record-audio-video-stream
-  <li><a href="/sfu-broadcast/index.html">sfu-broadcast</a> & <a href="/sfu-watch/index.html">sfu-watch
+  <li><a href="/broadcaster/index.html">broadcaster</a> &amp; <a href="/viewer/index.html">viewer
 <script src="index.js"></script>