From 81e788b9c0d089ad76ed4d7076505b6962cd9c60 Mon Sep 17 00:00:00 2001
From: saquibaijaz <saquibaijaz@navgurukul.org>
Date: Mon, 13 Mar 2023 23:09:03 +0530
Subject: [PATCH] Added validation for empty username and fixed undefined
 message

---
 .gitignore        |   3 +
 index.js          |  23 +-
 package-lock.json | 760 +++++++++++++++++++++++++++++++++++++++++++++-
 views/index.ejs   | 153 +++++++---
 4 files changed, 881 insertions(+), 58 deletions(-)
 create mode 100644 .gitignore

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 00000000..c6873c31
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+node_modules/
+npm-debug.log
+package-lock.json
diff --git a/index.js b/index.js
index 8e9febf1..b5eadf7e 100644
--- a/index.js
+++ b/index.js
@@ -3,26 +3,29 @@ const app = express();
 const http = require('http').Server(app);
 const io = require('socket.io')(http);
 
-app.get('/', function(req, res) {
+app.get('/', function (req, res) {
     res.render('index.ejs');
 });
 
-io.sockets.on('connection', function(socket) {
-    socket.on('username', function(username) {
-        socket.username = username;
-        io.emit('is_online', '🔵 <i>' + socket.username + ' join the chat..</i>');
+io.sockets.on('connection', function (socket) {
+    socket.on('username', function (username) {
+        if (username) { // check if username is not null or empty
+            socket.username = username;
+            io.emit('is_online', '🔵 <i>' + socket.username + ' joined the chat..</i>');
+        }
     });
 
-    socket.on('disconnect', function(username) {
-        io.emit('is_online', '🔴 <i>' + socket.username + ' left the chat..</i>');
+    socket.on('disconnect', function (username) {
+        if (socket.username) { // check if username is not null or empty
+            io.emit('is_online', '🔴 <i>' + socket.username + ' left the chat..</i>');
+        }
     })
 
-    socket.on('chat_message', function(message) {
+    socket.on('chat_message', function (message) {
         io.emit('chat_message', '<strong>' + socket.username + '</strong>: ' + message);
     });
-
 });
 
-const server = http.listen(8080, function() {
+const server = http.listen(8080, function () {
     console.log('listening on *:8080');
 });
\ No newline at end of file
diff --git a/package-lock.json b/package-lock.json
index c72f16df..46ac727b 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,8 +1,766 @@
 {
   "name": "node-simple-group-chat",
   "version": "1.0.0",
-  "lockfileVersion": 1,
+  "lockfileVersion": 2,
   "requires": true,
+  "packages": {
+    "": {
+      "name": "node-simple-group-chat",
+      "version": "1.0.0",
+      "license": "ISC",
+      "dependencies": {
+        "ejs": "^2.6.1",
+        "express": "^4.16.4",
+        "socket.io": "^2.2.0"
+      }
+    },
+    "node_modules/accepts": {
+      "version": "1.3.5",
+      "resolved": "https://registry.npmjs.org/accepts/-/accepts-1.3.5.tgz",
+      "integrity": "sha1-63d99gEXI6OxTopywIBcjoZ0a9I=",
+      "dependencies": {
+        "mime-types": "~2.1.18",
+        "negotiator": "0.6.1"
+      },
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+      }
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+      "integrity": "sha1-/ts5T58OAqqXaOcCvaI7UF+ufh8="
+    },
+    "node_modules/array-flatten": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/array-flatten/-/array-flatten-1.1.1.tgz",
+      "integrity": "sha1-ml9pkFGx5wczKPKgCJaLZOopVdI="
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+    "node_modules/arraybuffer.slice": {
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diff --git a/views/index.ejs b/views/index.ejs
index 46292c42..9cd228a9 100644
--- a/views/index.ejs
+++ b/views/index.ejs
@@ -1,50 +1,109 @@
 <!DOCTYPE html>
 <html>
-  <head>
-    <title>Simple Group Chat on Node.js</title>
-    <style>
-        * { margin: 0; padding: 0; box-sizing: border-box; }
-        body { font: 13px Helvetica, Arial; }
-        form { background: #fff; padding: 3px; position: fixed; bottom: 0; width: 100%; border-color: #000; border-top-style: solid; border-top-width: 1px;}
-        form input { border-style: solid; border-width: 1px; padding: 10px; width: 85%; margin-right: .5%; }
-        form button { width: 9%; background: rgb(130, 224, 255); border: none; padding: 10px; margin-left: 2%; }
-        #messages { list-style-type: none; margin: 0; padding: 0; }
-        #messages li { padding: 5px 10px; }
-        #messages li:nth-child(odd) { background: #eee; }
-    </style>
-    <script src="../../socket.io/socket.io.js"></script>
-    <script src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
-  </head>
-  <body>
-    <ul id="messages"></ul>
-    <form action="/" method="POST" id="chatForm">
-      <input id="txt" autocomplete="off" autofocus="on" oninput="isTyping()" placeholder="type your message here..." /><button>Send</button>
-    </form>
-    <script>
-            var socket = io.connect('http://localhost:8080');
-
-            // submit text message without reload/refresh the page
-            $('form').submit(function(e){
-                e.preventDefault(); // prevents page reloading
-                socket.emit('chat_message', $('#txt').val());
-                $('#txt').val('');
-                return false;
-            });
-
-            // append the chat text message
-            socket.on('chat_message', function(msg){
-                $('#messages').append($('<li>').html(msg));
-            });
-
-            // append text if someone is online
-            socket.on('is_online', function(username) {
-                $('#messages').append($('<li>').html(username));
-            });
-
-            // ask username
-            var username = prompt('Please tell me your name');
-            socket.emit('username', username);
-
-    </script>
-  </body>
+
+<head>
+  <title>Simple Group Chat on Node.js</title>
+  <style>
+    * {
+      margin: 0;
+      padding: 0;
+      box-sizing: border-box;
+    }
+
+    body {
+      font: 13px Helvetica, Arial;
+    }
+
+    form {
+      background: #fff;
+      padding: 3px;
+      position: fixed;
+      bottom: 0;
+      width: 100%;
+      border-color: #000;
+      border-top-style: solid;
+      border-top-width: 1px;
+    }
+
+    form input {
+      border-style: solid;
+      border-width: 1px;
+      padding: 10px;
+      width: 85%;
+      margin-right: .5%;
+    }
+
+    form button {
+      width: 9%;
+      background: rgb(130, 224, 255);
+      border: none;
+      padding: 10px;
+      margin-left: 2%;
+    }
+
+    #messages {
+      list-style-type: none;
+      margin: 0;
+      padding: 0;
+    }
+
+    #messages li {
+      padding: 5px 10px;
+    }
+
+    #messages li:nth-child(odd) {
+      background: #eee;
+    }
+  </style>
+  <script src="../../socket.io/socket.io.js"></script>
+  <script src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
+</head>
+
+<body>
+  <h2>This is a Chat using web sockets</h2>
+  <ul id="messages"></ul>
+  <form action="/" method="POST" id="chatForm">
+    <input id="txt" autocomplete="off" autofocus="on" oninput="isTyping()"
+      placeholder="type your message here..." /><button>Send</button>
+  </form>
+  <script>
+    var socket = io.connect('http://localhost:8080');
+
+    // submit text message without reload/refresh the page
+    $('form').submit(function (e) {
+      e.preventDefault(); // prevents page reloading
+      socket.emit('chat_message', $('#txt').val());
+      $('#txt').val('');
+      return false;
+    });
+
+    // append the chat text message
+    socket.on('chat_message', function (msg) {
+      $('#messages').append($('<li>').html(msg));
+    });
+
+    // append text if someone is online
+    socket.on('is_online', function (username) {
+      $('#messages').append($('<li>').html(username));
+    });
+
+
+    function getUsername() {
+      var username = prompt('Please tell me your name');
+      if (username === null || username.trim() === '') {
+        // if username is empty or user clicked cancel, show error message
+        alert('You cannot join the chat without entering a username. Please refresh the page and add a username to join the chat.');
+      }
+      return username;
+    }
+
+    var username = getUsername();
+
+    if (username !== null && username.trim() !== '') {
+      socket.emit('username', username);
+    }
+
+  </script>
+</body>
+
 </html>
\ No newline at end of file