Firebaseでのリアルタイムwebアプリについて

HTML
1 <script>
2   function _assert(desc, v) {
3     if (v) {
4       return;
5     }
6     else {
7       let caller = _assert.caller || 'Top level';
8       console.error('ASSERT in %s, %s is :', caller, desc, v);
9     }
10   }
11  </script>
12</head>
13<body>
14  firebase signaling for multi-party (trickle ICE)<br />
15  <button type="button" onclick="startVideo();">Start Video</button>
16  <button type="button" onclick="stopVideo();">Stop Video</button>
17  &nbsp;
18  <button type="button" onclick="connect();">Connect</button>
19  <button type="button" onclick="hangUp();">Hang Up</button> 
20  &nbsp;
21  <a id="room_link" href="" target="_blank">Open another window (link to this room)</a>
22  <a id="mail_link" href="" target="_blank">Mail link of this room</a>
23  <div>
24    <video id="local_video" autoplay style="width: 160px; height: 120px; border: 1px solid black;"></video>
25  </div>
26  <div id="container">
27  </div>
28  <!--
29  <p>SDP to send:<br />
30    <textarea id="text_for_send_sdp" rows="5" cols="60" readonly="readonly">SDP to send</textarea>
31  </p>
32  <p>SDP received:&nbsp;
33    <button type="button" onclick="onSdpText();">Receive remote SDP</button>
34    <br />
35    <textarea id="text_for_receive_sdp" rows="5" cols="60"></textarea>
36  </p>
37  -->
38</body>
39<script type="text/javascript">
40  let localVideo = document.getElementById('local_video');
41  //let remoteVideo = document.getElementById('remote_video');
42  let localStream = null;
43  //let peerConnection = null;
44  //let textForSendSdp = document.getElementById('text_for_send_sdp');
45  //let textToReceiveSdp = document.getElementById('text_for_receive_sdp');
46
47  // ---- for multi party -----
48  let peerConnections = [];
49  let remoteStreams = [];
50  let remoteVideos = [];
51  const MAX_CONNECTION_COUNT = 3;
52
53  // --- multi video ---
54  let container = document.getElementById('container');
55  _assert('container', container);
56
57  // --- prefix -----
58  navigator.getUserMedia  = navigator.getUserMedia    || navigator.webkitGetUserMedia ||
59                            navigator.mozGetUserMedia || navigator.msGetUserMedia;
60  RTCPeerConnection = window.RTCPeerConnection || window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
61  RTCSessionDescription = window.RTCSessionDescription || window.webkitRTCSessionDescription || window.mozRTCSessionDescription;
62
63
64  /*---
65  // ----- use socket.io ---
66  let port = 3002;
67  let socket = io.connect('http://localhost:' + port + '/');
68    let room = getRoomName();
69  socket.on('connect', function(evt) {
70    console.log('socket.io connected. enter room=' + room );
71    socket.emit('enter', room);
72  });
73  socket.on('message', function(message) {
74    console.log('message:', message);
75    let fromId = message.from;
76
77    if (message.type === 'offer') {
78      // -- got offer ---
79      console.log('Received offer ...');
80      //let offer = message.sessionDescription;
81      let offer = new RTCSessionDescription(message);
82      setOffer(fromId, offer);
83    }
84    else if (message.type === 'answer') {
85      // --- got answer ---
86      console.log('Received answer ...');
87      //let answer = message.sessionDescription;
88      let answer = new RTCSessionDescription(message);
89      setAnswer(fromId, answer);
90    }
91    else if (message.type === 'candidate') {
92      // --- got ICE candidate ---
93      console.log('Received ICE candidate ...');
94      let candidate = new RTCIceCandidate(message.ice);
95      console.log(candidate);
96      addIceCandidate(fromId, candidate);
97    }
98    else if (message.type === 'call me') {
99      if (! isReadyToConnect()) {
100        console.log('Not ready to connect, so ignore');
101        return;
102      }
103      else if (! canConnectMore()) {
104        console.warn('TOO MANY connections, so ignore');
105      }
106
107      if (isConnectedWith(fromId)) {
108        // already connnected, so skip
109        console.log('already connected, so ignore');
110      }
111      else {
112        // connect new party
113        makeOffer(fromId);
114      }
115    }
116    else if (message.type === 'bye') {
117      if (isConnectedWith(fromId)) {
118        stopConnection(fromId);
119      }
120    }
121  });
122  socket.on('user disconnected', function(evt) {
123    console.log('====user disconnected==== evt:', evt);
124    let id = evt.id;
125    if (isConnectedWith(id)) {
126      stopConnection(id);
127    }
128  });
129  ---*/
130  
131  // ----- use firebase.io ----
132  const dataDebugFlag = false;
133  let room = getRoomName();
134  // Initialize Firebase
135  let config = {
136    apiKey: "AIzaSyByIlgG450k2OlUr9QQhgCIdZudK_NJHb8",  // <-- please set your API key
137    databaseURL: "https://test-1f1b0.firebaseio.com/",  // <-- please set your database URL
138  };
139  let databaseRoot = ''; // <--- plaase set your database root for signaling
140  firebase.initializeApp(config);
141  let database = firebase.database();
142  let roomBroadcastRef;
143  let clientRef;
144  let clientId;
145
146  joinRoom(room);
147  setRoomLink(room);
148
149  function joinRoom(room) {
150    console.log('join room name = ' + room);
151
152    let key = database.ref(databaseRoot + room + '/_join_').push({ joined : 'unknown'}).key
153    clientId = 'member_' + key;
154    console.log('joined to room=' + room + ' as clientId=' + clientId);
155    database.ref(databaseRoot + room + '/_join_/' + key).update({ joined : clientId});
156    
157    
158    // remove join object
159    if (! dataDebugFlag) {
160      let jooinRef =  database.ref(databaseRoot + room + '/_join_/' + key);
161      jooinRef.remove();
162    }
163      
164    roomBroadcastRef = database.ref(databaseRoot + room + '/_broadcast_');
165    roomBroadcastRef.on('child_added', function(data) {
166      console.log('roomBroadcastRef.on(data) data.key=' + data.key + ', data.val():', data.val());
167      let message = data.val();
168      let fromId = message.from;
169      if (fromId === clientId) {
170        // ignore self message
171        return;
172      }
173      
174      if (message.type === 'call me') {
175        if (! isReadyToConnect()) {
176          console.log('Not ready to connect, so ignore');
177          return;
178        }
179        else if (! canConnectMore()) {
180          console.warn('TOO MANY connections, so ignore');
181        }
182
183        if (isConnectedWith(fromId)) {
184          // already connnected, so skip
185          console.log('already connected, so ignore');
186        }
187        else {
188          // connect new party
189          makeOffer(fromId);
190        }
191      }
192      else if (message.type === 'bye') {
193        if (isConnectedWith(fromId)) {
194          stopConnection(fromId);
195        }
196      }
197    });
198
199    clientRef = database.ref(databaseRoot + room + '/_direct_/' + clientId);
200    clientRef.on('child_added', function(data) {
201      console.log('clientRef.on(data)  data.key=' + data.key + ', data.val():', data.val());
202      let message = data.val();
203      let fromId = message.from;
204
205      if (message.type === 'offer') {
206        // -- got offer ---
207        console.log('Received offer ... fromId=' + fromId);
208        //let offer = message.sessionDescription;
209        let offer = new RTCSessionDescription(message);
210        setOffer(fromId, offer);
211      }
212      else if (message.type === 'answer') {
213        // --- got answer ---
214        console.log('Received answer ... fromId=' + fromId);
215        //let answer = message.sessionDescription;
216        let answer = new RTCSessionDescription(message);
217        setAnswer(fromId, answer);
218      }
219      else if (message.type === 'candidate') {
220        // --- got ICE candidate ---
221        console.log('Received ICE candidate ... fromId=' + fromId);
222        //let candidate = new RTCIceCandidate(message.ice);
223        let candidate = new RTCIceCandidate(JSON.parse(message.ice)); // <---- JSON
224        console.log(candidate);
225        addIceCandidate(fromId, candidate);
226      }
227      
228      if (! dataDebugFlag) {
229        // remove direct message
230        let messageRef =  database.ref(databaseRoot + room + '/_direct_/' + clientId + '/' + data.key);
231        messageRef.remove();
232      }
233    });
234  }
235  
236  function setRoomLink(room) {
237    let url = document.location.href;
238    let anchorLink = document.getElementById('room_link');
239    anchorLink.href = url;
240    let anchorMail = document.getElementById('mail_link');
241    let mailtoUrl = 'mailto:?subject=invitation-of-multi-party-videochat&body=' + url;
242    anchorMail.href = mailtoUrl;
243  }
244  // ----- use firebase.io ---- //
245  
246
247  // --- broadcast message to all members in room
248  function emitRoom(msg) {
249    //socket.emit('message', msg);
250    msg.from = clientId;
251    roomBroadcastRef.push(msg);
252  }
253
254  function emitTo(id, msg) {
255    //msg.sendto = id;
256    //socket.emit('message', msg);
257
258    console.log('===== sending from=' + clientId + ' ,  to=' + id);
259    msg.from = clientId;
260    database.ref(databaseRoot + room + '/_direct_/' + id).push(msg);
261  }
262

前提・実現したいこと

firebaseというサービスのhosting機能とリアルタイムデータベースを用いて、webアプリを作成しています。
リアルタイムのチャットとビデオチャットを同一のサイト内で行えるようなアプリを作ることを目的としています。

発生している問題・エラーメッセージ

以前はnode.jsのsocket.ioを使用してローカルでのリアルタイムビデオチャットは作成できたのですが、firebaseのサービスを利用し始めてからはオンラインで成功したことがありません。
まずfirebaseにおいてコマンドプロンプトでinitというコマンドを実行したときにできるpublicフォルダ内のindex.htmlのプログラムの書き換えができなくて困っています。
また、プログラム内でデータベースへのパスをしてもデータベース内にツリーが表示されず、データベースに接続できません。
以上の問題が現在起こっています。