Проблема с webrtc, не могу подключиться за звонок

Question

Я получил этот код на сайте tutorialspoint, который в основном содержит html-страницу, сервер и клиент, но не могу установить соединение

server.js

//require our websocket library 
var WebSocketServer = require('ws').Server; 

//creating a websocket server at port 9090 
var wss = new WebSocketServer({port: 8000}); 

//all connected to the server users 
var users = {};

//when a user connects to our sever 
wss.on('connection', function(connection) {

   console.log("User connected");

   //when server gets a message from a connected user 
   connection.on('message', function(message) { 

      var data;

      //accepting only JSON messages 
      try { 
         data = JSON.parse(message); 
      } catch (e) { 
         console.log("Invalid JSON"); 
         data = {}; 
      }

      //switching type of the user message 
      switch (data.type) { 
         //when a user tries to login 
         case "login": 
            console.log("User logged", data.name); 

            //if anyone is logged in with this username then refuse 
            if(users[data.name]) { 
               sendTo(connection, { 
                  type: "login", 
                  success: false 
               }); 
            } else { 
               //save user connection on the server 
               users[data.name] = connection; 
               connection.name = data.name;

               sendTo(connection, { 
                  type: "login", 
                  success: true 
               }); 
            } 

            break;

         case "offer": 
            //for ex. UserA wants to call UserB 
            console.log("Sending offer to: ", data.name); 

            //if UserB exists then send him offer details 
            var conn = users[data.name]; 

            if(conn != null) { 
               //setting that UserA connected with UserB 
               connection.otherName = data.name; 

               sendTo(conn, { 
                  type: "offer", 
                  offer: data.offer, 
                  name: connection.name 
               }); 
            } 

            break;

         case "answer": 
            console.log("Sending answer to: ", data.name); 
            //for ex. UserB answers UserA 
            var conn = users[data.name]; 

            if(conn != null) { 
               connection.otherName = data.name; 
               sendTo(conn, { 
                  type: "answer", 
                  answer: data.answer 
               });
            } 

            break;

         case "candidate": 
            console.log("Sending candidate to:",data.name); 
            var conn = users[data.name];  

            if(conn != null) { 
               sendTo(conn, { 
                  type: "candidate", 
                  candidate: data.candidate 
               }); 
            } 

            break;

         case "leave": 
            console.log("Disconnecting from", data.name); 
            var conn = users[data.name]; 
            if(conn)
               conn.otherName = null; 

            //notify the other user so he can disconnect his peer connection 
            if(conn != null) { 
               sendTo(conn, { 
                  type: "leave" 
               }); 
            }  

            break;

         default: 
            sendTo(connection, { 
               type: "error", 
               message: "Command not found: " + data.type 
            });

            break; 
      }  
   });

   //when user exits, for example closes a browser window 
   //this may help if we are still in "offer","answer" or "candidate" state 
   if (connection.otherName) {
    var conn = users[connection.otherName]; 
   conn.otherName = null;  

    if(conn != null) { 
// The connection is closed, trying to send at this point isn't a good idea
           sendTo(conn, { 
              type: "leave" 
          }); 
        }  
    }

   connection.send("Hello world"); 
}); 

function sendTo(connection, message) { 
   connection.send(JSON.stringify(message)); 
}

client.js

//our username 
var name; 
var connectedUser;

//connecting to our signaling server 
var conn = new WebSocket('ws://localhost:8000');

conn.onopen = function () { 
   console.log("Connected to the signaling server"); 
};

//when we got a message from a signaling server 
conn.onmessage = function (msg) { 
   console.log("Got message", msg.data); 
   var data = JSON.parse(msg.data); 

   switch(data.type) { 
      case "login": 
         handleLogin(data.success); 
         break; 
      //when somebody wants to call us 
      case "offer": 
         handleOffer(data.offer, data.name); 
         break; 
      case "answer": 
         handleAnswer(data.answer); 
         break; 
      //when a remote peer sends an ice candidate to us 
      case "candidate": 
         handleCandidate(data.candidate); 
         break; 
      case "leave": 
         handleLeave(); 
         break; 
      default: 
         break; 
   } 
}; 

conn.onerror = function (err) { 
   console.log("Got error", err); 
};

//alias for sending JSON encoded messages 
function send(message) { 
   //attach the other peer username to our messages 
   if (connectedUser) { 
      message.name = connectedUser; 
   } 

   conn.send(JSON.stringify(message)); 
};

//****** 
//UI selectors block 
//****** 

var loginPage = document.querySelector('#loginPage'); 
var usernameInput = document.querySelector('#usernameInput'); 
var loginBtn = document.querySelector('#loginBtn');

var callPage = document.querySelector('#callPage'); 
var callToUsernameInput = document.querySelector('#callToUsernameInput');
var callBtn = document.querySelector('#callBtn'); 

var hangUpBtn = document.querySelector('#hangUpBtn'); 
var localAudio = document.querySelector('#localAudio'); 
var remoteAudio = document.querySelector('#remoteAudio'); 

var yourConn; 
var stream; 

callPage.style.display = "none";

// Login when the user clicks the button 
loginBtn.addEventListener("click", function (event) { 
   name = usernameInput.value; 

   if (name.length > 0) { 
      send({ 
         type: "login", 
         name: name 
      }); 
   } 

});

function handleLogin(success) { 
   if (success === false) { 
      alert("Ooops...try a different username"); 
   } else { 
      loginPage.style.display = "none"; 
      callPage.style.display = "block"; 

      //********************** 
      //Starting a peer connection 
      //********************** 

      //getting local audio stream 
      navigator.webkitGetUserMedia({ video: false, audio: true }, function (myStream) { 
         stream = myStream; 

         //displaying local audio stream on the page 
         localAudio.src = window.URL.createObjectURL(stream);

         //using Google public stun server 
         var configuration = { 
            "iceServers": [{ "url": "stun:stun2.1.google.com:19302" }] 
         }; 

         yourConn = new webkitRTCPeerConnection(configuration); 

         // setup stream listening 
         yourConn.addStream(stream); 

         //when a remote user adds stream to the peer connection, we display it 
         yourConn.onaddstream = function (e) { 
            remoteAudio.src = window.URL.createObjectURL(e.stream); 
         }; 

         // Setup ice handling 
         yourConn.onicecandidate = function (event) { 
            if (event.candidate) { 
               send({ 
                  type: "candidate", 
                  candidate: event.candidate 
               }); 
            } 
         }; 

      }, function (error) { 
         console.log(error); 
      }); 

   } 
};

//initiating a call 
callBtn.addEventListener("click", function () { 
   var callToUsername = callToUsernameInput.value; 

   if (callToUsername.length > 0) { 
      connectedUser = callToUsername; 

      // create an offer 
      yourConn.createOffer(function (offer) { 
         send({
            type: "offer", 
            offer: offer 
         }); 

         yourConn.setLocalDescription(offer); 
      }, function (error) { 
         alert("Error when creating an offer"); 
      }); 
   } 
});

//when somebody sends us an offer 
function handleOffer(offer, name) { 
   connectedUser = name; 
   yourConn.setRemoteDescription(new RTCSessionDescription(offer)); 

   //create an answer to an offer 
   yourConn.createAnswer(function (answer) { 
      yourConn.setLocalDescription(answer); 

      send({ 
         type: "answer", 
         answer: answer 
      });

   }, function (error) { 
      alert("Error when creating an answer"); 
   }); 

};

//when we got an answer from a remote user 
function handleAnswer(answer) { 
   yourConn.setRemoteDescription(new RTCSessionDescription(answer)); 
};

//when we got an ice candidate from a remote user 
function handleCandidate(candidate) { 
   yourConn.addIceCandidate(new RTCIceCandidate(candidate)); 
};

//hang up
hangUpBtn.addEventListener("click", function () { 
   send({ 
      type: "leave" 
   }); 

   handleLeave(); 
});

function handleLeave() { 
   connectedUser = null; 
   remoteAudio.src = null; 

   yourConn.close(); 
   yourConn.onicecandidate = null; 
   yourConn.onaddstream = null; 
};

index.html

<html>

   <head> 
      <title>WebRTC Voice Demo</title> 
      <link rel = "stylesheet" href = "node_modules/bootstrap/dist/css/bootstrap.min.css"/> 
   </head>

   <style> 
      body { 
         background: #eee; 
         padding: 5% 0; 
      } 
   </style>

   <body> 
      <div id = "loginPage" class = "container text-center"> 

         <div class = "row"> 
            <div class = "col-md-4 col-md-offset-4">

               <h2>WebRTC Voice Demo. Please sign in</h2>

               <label for = "usernameInput" class = "sr-only">Login</label> 
               <input type = "email" id = "usernameInput" 
                  class = "form-control formgroup"
                  placeholder = "Login" required = "" autofocus = ""> 
               <button id = "loginBtn" class = "btn btn-lg btn-primary btnblock">
                  Sign in</button> 
            </div> 
         </div> 

      </div>

      <div id = "callPage" class = "call-page">

         <div class = "row"> 

            <div class = "col-md-6 text-right"> 
               Local audio: <audio id = "localAudio" 
               controls autoplay></audio> 
            </div>

            <div class = "col-md-6 text-left"> 
               Remote audio: <audio id = "remoteAudio" 
                  controls autoplay></audio> 
            </div> 

         </div> 

         <div class = "row text-center"> 
            <div class = "col-md-12"> 
               <input id = "callToUsernameInput" 
                  type = "text" placeholder = "username to call" /> 
               <button id = "callBtn" class = "btn-success btn">Call</button> 
               <button id = "hangUpBtn" class = "btn-danger btn">Hang Up</button> 
            </div> 
         </div>

      </div> 

      <script src = "client.js"></script> 

   </body>

</html>

package.json, внутри папки audiochat

{ 
   "name": "webrtc-audiochat", 
   "version": "0.1.0", 
   "description": "webrtc-audiochat", 
   "author": "Author", 
   "license": "BSD-2-Clause" 
}

Как мне это сделать?

Ничего не появляется, когда я нажимаю кнопку вызова, я хотел позвонить, но не могу сделать это и не знаю, как решить