A POC (proof of concept) system to modernize a front-end project with live updates from various programs while minimizing changes to those source codes.
There are no intended changes to be made to this POC. It has served its purpose.
This program listens to UDP messages on one thread and handles a websocket server on another thread. Any message arriving on the specified UDP port will be broadcast to the WebSocket clients. Any message arriving on the websocket will be received but ignored.
$ ./live_gateway --udp_port 3030 --websocket_port 3031HTML
<!DOCTYPE html>
<html lang="en">
<head>
<title>Live Gateway</title>
</head>
<body>
<h1>Live Gateway</h1>
<div id="log">
<p><em>Connecting...</em></p>
</div>
<input type="text" id="text" />
<button type="button" id="send">send</button>
<script type="text/javascript">
const chat = document.getElementById('log');
const text = document.getElementById('text');
const uri = 'ws://127.0.0.1:3031/listen';
const ws = new WebSocket(uri);
function message(data) {
const line = document.createElement('p');
line.innerText = data;
chat.appendChild(line);
}
ws.onopen = function() {
chat.innerHTML = '<p><em>Connected!</em></p>';
};
ws.onmessage = function(msg) {
message('<Server>: ' + msg.data);
};
ws.onclose = function() {
chat.getElementsByTagName('em')[0].innerText = 'Disconnected!';
};
send.onclick = function() {
const msg = text.value;
ws.send(msg);
text.value = '';
message('<You>: ' + msg);
};
</script>
</body>
</html>Bash
$ nc -u 127.0.0.1 3030
Hello WorldPHP
<?php
$sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
$msg = "Hello World";
$len = strlen($msg);
socket_sendto($sock, $msg, $len, 0, '127.0.0.1', 3030);
socket_close($sock);
?>Ruby
require 'socket'
sock = UDPSocket.new
sock.connect("127.0.0.1", 3030)
sock.send "Hello World", 0Python
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.connect(("127.0.0.1", 3030))
sock.send(b"Hello World")