I'm designing a chatroom in ratchet websockets to be as responsive as possible. It knows when a user leaves the page, and everything like that. But if a user/client for example loses its connection with the server, the issue is the client cant let the server know it has disconnected, because it has already disconnected and cant send the server a message. So how do I track when a chat client has lost their internet connection and is no longer online?
Two possible solutions I can think of:
server polls the clients once every 15 mins to half hour to check to see who is online. Clients who do not respond get disconnected. Is this possible to do without interrupting everything else going on in php? if so how? and where do I put the code? I saw something about
addPeriodicTimer()fromLoopInterfacebut im not sure if that would do the job or where the function would fit into my code. Also does it callsleep()function because that would not be good. I still want other tasks happening in the background while this function is on a timer (if possible in php)onClose()method in php Can this detect when a user has really disconnected in every circumstance? If so, when this event fires off, how can I find out which user was disconnected? it only passes a ConnectionInterface and no message.
Sorry, im still new to the ratchet library and still trying to work out how to achieve this task.
my code for server.php:
<?php
require($_SERVER['DOCUMENT_ROOT'].'/var/www/html/vendor/autoload.php');
use Ratchet\Server\IoServer;
use Ratchet\Http\HttpServer;
use Ratchet\WebSocket\WsServer;
$server = IoServer::factory(new HttpServer(new WsServer(new Chat)), 8080);
$server->run();
?>
code for app.js
// JavaScript Document
var chat = document.getElementById("chatwindow");
var msg = document.getElementById("messagebox");
var refInterval = 0;
var timeup = false;
var awaytimer;
var socket = new WebSocket("ws://52.39.48.172:8080");
var openn = false;
function addMessage(msg){
"use strict";
chat.innerHTML += "<p>" + msg + "</p>";
}
msg.addEventListener('keypress', function(evt){
"use strict";
if(evt.charCode != 13)
return;
evt.preventDefault();
if(msg.value == "" || !openn)
return;
socket.send(JSON.stringify({
msg: msg.value,
uname: nme,
uid: id,
tag: "[msgsend]"
}));
msg.value = "";
});
socket.onopen = function(evt) {
openn = true;
socket.send(JSON.stringify({
uname: nme,
uid: id,
tag: "[connected]"
}));
};
socket.onmessage = function(evt) {
var data = JSON.parse(evt.data);
if(data.tag == "[connected]")
{
addMessage(data.uname + " has connected...");
}
else if(data.tag == "[bye]")
{
addMessage(data.uname + " has left the room...");
if(data.uname == nme)
socket.close();
}
else if(data.tag == "[msgsend]")
{
addMessage(data.uname + ": " + data.msg);
}
};
window.onfocus = refPage;
function refPage()
{
if(timeup == true)
{
if(refInterval == 1)
{
refInterval = 0;
location.reload();
}
}
else
{
clearTimeout(awaytimer);
}
timeup = false;
}
window.onblur = timelyExit;
function timelyExit()
{
refInterval = 1;
// change this to trigger some kind of inactivity timer
awaytimer = setTimeout(function(){socket.send(JSON.stringify({
uname: nme,
uid: id,
tag: "[bye]"
})); timeup=true; }, 900000);
}
window.onoffline = window.onunload = window.onbeforeunload = confirmExit;
function confirmExit()
{
socket.send(JSON.stringify({
uname: nme,
uid: id,
tag: "[bye]"
}));
socket.close();
}
socket.onclose = function() {
openn = false;
//cant send server this message because already closed.
/*
socket.send(JSON.stringify({
uname: nme,
uid: id,
tag: "[bye]"
}));
*/
socket.close();
};
Code for chat.php
<?php
error_reporting(E_ALL ^ E_NOTICE);
session_id($_GET['sessid']);
if(!session_id)
session_start();
$userid = $_SESSION["userid"];
$username = $_SESSION["username"];
$isadmin = $_SESSION["isadmin"];
use Ratchet\MessageComponentInterface;
use Ratchet\ConnectionInterface;
class Chat implements MessageComponentInterface
{
protected $clients;
public function __construct()
{
$this->clients = new \SplObjectStorage;
}
public function onOpen(ConnectionInterface $conn)
{
$this->clients->attach($conn);
}
public function onClose(ConnectionInterface $conn)
{
$this->clients->detach($conn);
}
public function onMessage(ConnectionInterface $conn, $msg)
{
$msgjson = json_decode($msg);
$tag = $msgjson->tag;
if($tag == "[msgsend]")
{
foreach($this->clients as $client)
{
$client->send($msg);
}
}
else if($tag == "[bye]")
{
foreach($this->clients as $client)
{
$client->send($msg);
}
onClose($conn);
}
else if($tag == "[connected]")
{
//store client information
//send out messages
foreach($this->clients as $client)
{
$client->send($msg);
}
}
}
public function onError(ConnectionInterface $conn, Exception $e)
{
echo "Error: " . $e->getMessage();
$conn -> close();
}
}
?>
Edit: just tested and confirmed onClose() method doesnt fire when internet connection is terminated.
is there a way i can still go about the first solution?
