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Why Websocket connection is disconneting after sending message on iOS 15 devices?

I am building a website based on web socket communication. Its is working fine until iOS 14 but started breaking from iOS 15. Web socket java script client is able to open connection to server, but upon trying to send a message, the connection is getting closed. Following is my html and JS code.
function start_websocket() {
connection = new WebSocket("wss://localhost/wss/");
connection.onopen = function () {
console.log('Connection Opened');
};
connection.onerror = function (error) {
console.log('WebSocket Error ' + error);
};
connection.onclose = function(){
console.log("Closed");
};
connection.onmessage = function (e) {
console.log("Message Received :" + e.data);
};
}
function myFunction() {
var testText = document.getElementById("testText");
if (testText.value != "" && connection.readyState === connection.OPEN) {
connection.send("Test");
}
}
start_websocket();
myFunction() is an on-click event of a button.
A Java Websocket server is used, which will decode and send the messages based on the Data framing in https://datatracker.ietf.org/doc/html/rfc6455#section-5.
Saw different articles on the Web, but didn't found a solution to this issue. Any suggestions are much appreciated. Looking forward for your answers
Thanks in advance.

Proxy Chrome Storage

I am trying to get my proxy chrome extention to keep on/off after closing using chrome.local.storage. This does not seem to work, can anyone give some examples on how to get this kind of code working?
Right now my pac proxy works and turns on and off. The local storage does not seem to work at all, but I followed all the examples on the developer.chrome website. That does not work.
var channels;
var ny;
function endvpn() {
// turn off vpn
var config = {
mode: "pac_script",
pacScript: {
data: "function FindProxyForURL(url, host) {\n" +
" if (host == 'google.com /*')\n" +
" return 'PROXY blackhole:80';\n" +
" return 'DIRECT';\n" +
"}"
}
};
chrome.storage.local.set({ny: false});
// change vpn button
document.getElementById("vpnbtn").innerHTML = "Start Vpn";
// turn off event lisner for endvpn and start event listner to go back to startvpn
document.getElementById('vpnbtn').removeEventListener('click', endvpn, false);
document.getElementById("vpnbtn").addEventListener("click", startvpn);
}
function startvpn() {
// turn on vpn
var config = {
mode: "pac_script",
pacScript: {
data: "function FindProxyForURL(url, host) {\n" +
" if (host == 'google.com /*')\n" +
" return 'PROXY blackhole:80';\n" +
" return 'PROXY 209.127.191.180:80';\n" +
"}"
}
};
chrome.storage.local.set({ny: true});
// change vpn button
document.getElementById("vpnbtn").innerHTML = "Stop Vpn";
// turn off event lisner for startvpn and start event listner to go back to endvpn
document.getElementById('vpnbtn').removeEventListener('click', startvpn, false);
document.getElementById("vpnbtn").addEventListener("click", endvpn);
}
var rez = chrome.storage.local.get(ny);
alert(rez);
// start at startvpn
document.getElementById("vpnbtn").addEventListener("click", startvpn);

Most apis within Chrome extensions are asyncronous. See the documentation here. You can provide a callback as the second argument to the 'get' function where you can use the variable:
chrome.storage.local.get('ny', function(result){
alert(result.ny);
});

Websockets not working

I have the following code in javascript:
function ConnectWebSocket() {
if ("WebSocket" in window) {
myWebsocket = new WebSocket("wss://myserver/mychannel");
myWebsocket.onmessage = function(evt) {
alert("onmessage");
}
myWebsocket.onopen = function() {
alert("onopen");
myWebsocket.send("msg0");
myWebsocket.send("msg1");
myWebsocket.send("msg2");
}
myWebsocket.onclose = function() {
alert("onclose");
ConnectWebSocket();
}
} else {
// Do something if there is no websockets support
}
}
ConnectWebSocket();
The problem is that in Firefox, the connection is closed after sending the messages, and reopened due to the command on the onclose event. If I try to send only one message on onopen, the connection keeps opened, but if I try to send more than one message, the connection shut down. This issue appears only in Firefox, not in Chrome, not in IE, not in Safari.
Can someone help me? In other browsers like IE or Chrome, once the connection is created, it keep opened until I leave the page. I have the 40.0.3v of Firefox

Try this example:
var url = "ws://echo.websocket.org";
if (!window.WebSocket) alert("WebSocket not supported by this browser");
var myWebSocket = {
connect: function () {
var location = url
this._ws = new WebSocket(location);
this._ws.onopen = this._onopen;
this._ws.onmessage = this._onmessage;
this._ws.onclose = this._onclose;
this._ws.onerror = this._onerror;
},
_onopen: function () {
console.debug("WebSocket Connected");
},
_onmessage: function (message) {
console.debug("Message Recieved: " + message.data);
},
_onclose: function () {
console.debug("WebSocket Closed");
kiosk.connect();
},
_onerror: function (e) {
console.debug("Error occured: " + e);
},
_send: function (message) {
console.debug("Message Send: " + message);
if (this._ws) this._ws.send(message);
}
};
myWebSocket.connect();
setInterval(function() {
myWebSocket._send('msg1');
}, 5000);
Here is a JSFidlle

It may be that your support var is not behaving as you expect. The following code works in FireFox without closing the connection:
function ConnectWebSocket() {
if ("WebSocket" in window) {
myWebsocket = new WebSocket("ws://echo.websocket.org/");
myWebsocket.onmessage = function (evt) {
alert("onmessage");
}
myWebsocket.onopen = function () {
alert("onopen");
myWebsocket.send("a test message");
}
myWebsocket.onclose = function () {
alert("onclose");
ConnectWebSocket();
}
} else {
// Do something if there is no websockets support
}
}
ConnectWebSocket();
Example Fiddle
You can use the tool on Websocket.org to make sure websockets are
working correctly in your browser.
Or (although your issue is with FF) you can use the steps listed
here to debug websockets.

Try it.
var WS = window.WebSocket || window.MozWebSocket;
if (WS){
var websocket = new WS("wss://myserver/mychannel");
}

Firefox OS alarm to wake up closed app

Looking at documentation it looks like the alarm api can be used to restart an app at a certain time
I changed the code from boilerplate example in this way
// Alarm API
var alarmDate = new Date("Jul 8, 2014 19:35:00"),
addAlarm = document.querySelector("#add-alarm"),
alarmDisplay = document.querySelector("#alarm-display");
if (addAlarm) {
addAlarm.onclick = function () {
var alarm = navigator.mozAlarms.add(alarmDate, "honorTimezone", {
"optionalData" : "I am data"
});
alarm.onsuccess = function () {
var request = window.navigator.mozApps.getSelf();
request.onsuccess = function() {
navigator.mozSetMessageHandler("alarm", function (mozAlarm) {
request.result.launch();
alert("alarm fired: " + JSON.stringify(mozAlarm.data));
});
};
request.onerror = function() {
alert("Error: " + request.error.name);
};
};
The code seems to bring up the app only if the app is running (even in background) BUT not if the app is closed.
Is this the intended behaviour? Any way to restart a closed app?
Also is it possible to bring up the app in foreground and make it unlock the screen?
Thanks
UPDATE
Just as a clarification, the issue appears when the system memory load requires killing an app. Android provides a way to schedule restart of an app (while iOS, afaik, does not...).
It would be useful if an app could be restarted at the moment in which it's required.
That's also saving a lot of battery...

Your code is wrong: the setMessageHandler is created in the onsuccess handler of mozAlarms.add. That code will not be executed when the alarm fires. You need to always add the listener on app startup.
Here's some simple code that adds and responds to an alarm (from app-days-dhaka).
var request = navigator.mozAlarms.add(new Date((+new Date()) + 30000), 'ignoreTimezone', {
type: 'yolo'
});
console.log('setting to', new Date((+new Date()) + 30000) + '')
request.onsuccess = function() {
console.log('success');
}
request.onerror = function() {
console.error('err');
}
navigator.mozSetMessageHandler('alarm', function() {
console.log('alarm');
launchSelf();
});
function launchSelf() {
var request = window.navigator.mozApps.getSelf();
request.onsuccess = function() {
if (request.result) {
request.result.launch();
}
};
}
Open the app (this will set the alarm), then close the app immediately (via long press on home). After 30 seconds the app will open again automatically.

Reconnect hub necessary

I have simple project in ASP.NET Web site with signalr.
Code for start connection hub:
var scriptStarted = 'var myHub = $.connection.' + hubName + ';' + methodNameInitHub + '(myHub);';
$.connection.hub.error(function () {
alert("An error occured");
});
$.connection.hub.start()
.done(function () {
eval(scriptStarted);
myHub.server.registerClient($.connection.hub.id, clientIdentifier);
})
.fail(function () { alert("Could not Connect!"); });
This method is call in "methodNameInitHub + '(myHub);"
function methodInitEventHub(hub) {
if (hub) {
hub.client.addEvent = function (eventOperationName, eventType) {
$("#events").append("<li>" + eventOperationName + ", " + eventType + "</li>");
};
}
}
Code for stop connection hub:
$.connection.hub.stop();
When I load .aspx page and start hub all code execute without errors, but event from server not recieved.
After I stop and start again hub connection events begining received in client (browser)
http://clip2net.com/s/2CP2e
Why I need to restart connection hub for begin received event from server ?
Thanks.

The reason you're having issues is because you must have at least 1 client side hub function prior to calling start otherwise you will not be subscribed to the hub.
Try doing
myHub.client.foo = function() {}
prior to start.
The reason why it works after you stop then re-start the connection is because your script binds a new client method, hence allowing you to subscribe to the hub after you've restarted the connection.
Hope this helps!