trouble with private messaging - php

Question

Kindly Note: I know this might be a possible duplicate of other questions but i'd like help with my code!!
I'm trying to build a chat feature for my social network..I've used node.js and socket.io ...The prob with this code is that, the message is being delivered to every connected user instead of just the targeted to_user...The source of this code is from thenewboston tutorials...
I've built it as of now like this:
client.php
<div class="chat" hidden>
<textarea class="chat-name"><?php echo escape($data->username); ?></textarea>
<div class="chat-messages">
<?php
$chtrndr = $cht->renderchats(escape($data->id));
foreach ($chtrndr as $chtrndrs) {
echo '<div>' . $chtrndrs['m_from'] . ': ' . $chtrndrs['m_text'] . '</div><br>';
}
?>
</div>
<textarea class="chat-textarea" placeholder="Type your message"></textarea>
<div class="chat-status">Status:<span>Idle</span></div>
</div>
<!-- <script src="/socket.io/socket.io.js"></script> -->
<script src="http://127.0.0.1:8080/socket.io/socket.io.js"></script>
<script src="server.js"></script>
<script>
(function(){
var getNode = function(s) {
return document.querySelector(s);
},
//get required nodes
status = getNode('.chat-status span'),
messages = getNode('.chat-messages'),
textarea = getNode('.chat-textarea'),
chatName = getNode('.chat-name'),
statusDefault = status.textContent,
setStatus = function(s) {
status.textContent = s;
if(s!==statusDefault)
{
var delay = setTimeout(function(){
setStatus(statusDefault);
clearInterval(delay);
},3000);
}
};
setStatus('testing');
try {
var socket = io.connect('http://127.0.0.1:8080');
}
catch(e)
{
//set status to warn user
}
if(socket!==undefined)
{
//listen for output
socket.on('output',function(data){
if(data.length)
{
//loop through results
for(var x=0;x<data.length;x=x+1)
{
var message = document.createElement('div');
message.setAttribute('class','chat-message');
message.textContent = data[x].m_from + ': ' + data[x].m_text;
//append
messages.appendChild(message);
messages.insertBefore(message, messages.firstChild);
}
}
});
//listen for a status
socket.on('status',function(data){
setStatus((typeof data === 'object') ? data.message : data);
if(data.clear === true)
{
textarea.value = '';
}
});
//listen for keydown
textarea.addEventListener('keydown',function(event){
var self = this,
fname = <?php echo escape($_SESSION['user']); ?>,
tname = <?php echo $data->id; ?>;
if(event.which === 13 && event.shiftKey === false) {
socket.emit('input', {m_from:fname, m_to:tname, m_text:self.value});
event.preventDefault();
}
});
}
})();
</script>
And this is the server file:
SERVER.js
var client = require('socket.io').listen(8080).sockets;
var express = require('express');
var app = express();
var mysql = require('mysql');
var path = require('path');
var dbconn = mysql.createConnection({
host : 'localhost',
user : 'root',
password : '',
database : 'test'
});
app.use(express.static(path.resolve(__dirname, './css/')));
app.get('/',function(req,res){
res.sendFile(__dirname + '/index.html');
});
dbconn.connect(function(err){
if(err){
console.log('Database connection error');
}else{
console.log('Database connection successful');
}
client.on('connection',function(socket){
console.log('Data received from Db');
sendStatus = function(s){
socket.emit('status',s);
};
//wait for input
socket.on('input',function(data){
var fname = data.m_from,
tname = data.m_to,
m_text = data.m_text,
whitespacePattern = /^\s*$/;
if(whitespacePattern.test(m_text))
{
sendStatus('message is required');
}
else
{
var record = { m_from: fname, m_to:tname, m_text: m_text };
dbconn.query('INSERT INTO messages SET ?', record, function(err,res){
if(err) throw err;
client.emit('output',[data]);
sendStatus({
message: "message sent",
clear: true
});
});
}
});
});
});
i wud like to add the following functionality:
*(a)*Since it is a social network, it shud be capable of serving private chats, betn 2 logged in users...
(b) The messages shud be received by the receiver after he logs back in at a later time..
I've combed many pages on google n SO already and heard that rooms are my go-to. But being a noob in nodejs, idk how to implement the rooms to make private messaging possible...
If any1 cud help me code it or even set me on the right path, frm where i can learn to code in node.js with easy tutorials for beginners, it wud b a really gr8 help!! Thanx in advance!

Answer 1

Look it should be like every user in your application should have unique id
LOGIC
1.you have to emit the event from your backend(server side) on output_userId
Your frontEnd (client side) should listen to the socket event on output_userId
what this will do is like you are emitting the message for the specific user from server side and every user will be listening on output_userId which is their specific id. where userId is there unique id of the project.
example:
we have 3 users
1,2,3
now if user 1 is sending message to user 2
your events should be like
Server Side
Socket.emit(output_1)
client side
every client side user should listen to their output_userid
for user 1 it should be output_1
for user 2 it should be output_2
for user 3 it should be output_3