🚀 Server-Sent Events - One Way Messaging🚀
A server-sent event is when a web page automatically gets updates from a server, a unidirectional "push".
While other methods like Polling, Webhooks, Websockets, and Long live connections exist, SSEs stand out as a dedicated channel for sending updates to the client. 🔄
Examples? Think stock price updates, news feeds, sport results, device monitoring - SSEs are your go-to solution! 💡
The HTML5 spec calls it "EventSource".
Implementation Guide:
client side :
1. Create a new EventSource object, and specify the URL of the resource
2. the onmessage event occurs each time an update is received, you can put your logic here
<JS>
var source = new EventSource("sse_url");
source.onmessage = function(event) {
document.getElementById("result").innerHTML = event.data;
};
server side:
1. Set the "Content-Type" header to "text/event-stream"
2. Specify that the page should not cache
3. Output the data to send (Always start with "data: ")
4. Flush the output data back to the web page
<?php
header('Content-Type: text/event-stream');
header('Cache-Control: no-cache');
$time = date('r');
echo "data: The server time is: {$time}\n\n";
flush();
?>
Code examples referred from here
You can also check out this article for a python server implementation using generators
