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**Category:** Questions\
**Created:** [November 4, 2016, 4:16pm UTC](https://discourse.slimframework.com/t/how-to-use-html5-server-sent-events-sse/879 "2016-11-04T16:16:05Z")\
**Posts on this page:** 5\
**Page:** 1
**Author:**  [@SlimStorm](https://discourse.slimframework.com/u/SlimStorm)\
**Post date:** [November 4, 2016, 4:16pm UTC](https://discourse.slimframework.com/t/how-to-use-html5-server-sent-events-sse/879/1 "2016-11-04T16:16:05Z")
Hi,
See: [http://www.w3schools.com/HTML/html5\_serversentevents.asp](http://www.w3schools.com/HTML/html5_serversentevents.asp)
With just native PHP on the server side it’s a no-brainer, but how do I get this running with Slim3?
I need this badly for a project that updates a browser-client every 3 seconds
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**Author:**  [@TheLobos](https://discourse.slimframework.com/u/TheLobos)\
**Post date:** [November 4, 2016, 5:41pm UTC](https://discourse.slimframework.com/t/how-to-use-html5-server-sent-events-sse/879/2 "2016-11-04T17:41:31Z")
This is the first time I’ve heard of SSE (yes, my bad) but a first thought would be that if you don’t get a satisfying answer in the time you need, couldn’t the same thing be achieved by calling an Ajax function scheduled through setInterval()?
Maybe this helps, I just wanted to offer this suggestion.
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**Author:**  [@SlimStorm](https://discourse.slimframework.com/u/SlimStorm)\
**Post date:** [November 4, 2016, 5:48pm UTC](https://discourse.slimframework.com/t/how-to-use-html5-server-sent-events-sse/879/3 "2016-11-04T17:48:53Z")
That’s the way I’m doing it right now 🙂 … but It creates a lot of overhead as some intervals are 1 sec. The server is flooded with requests, compared to a simple loop that writest a few bytes every few seconds using SSE.
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**Author:**  [@tflight](https://discourse.slimframework.com/u/tflight)\
**Post date:** [November 5, 2016, 1:55pm UTC](https://discourse.slimframework.com/t/how-to-use-html5-server-sent-events-sse/879/4 "2016-11-05T13:55:18Z")
@SlimStorm, have a look at this comment in [Adding SSE requests to Slim](https://github.com/slimphp/Slim/issues/1959#issuecomment-250998762).
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**Author:**  [@SlimStorm](https://discourse.slimframework.com/u/SlimStorm)\
**Post date:** [November 5, 2016, 2:04pm UTC](https://discourse.slimframework.com/t/how-to-use-html5-server-sent-events-sse/879/5 "2016-11-05T14:04:15Z")
Presto, I did it. Reworked the CallbackStream in [https://github.com/phly/psr7examples](https://github.com/phly/psr7examples) and that did the trick.
Javascript snippet
`var evtSource = new EventSource(send_url);
evtSource.onmessage = function(event) {
if ( event.data.substr(0,3) == 'END') {
evtSource.close();
} else {
$('#result').html(event.data);
}
};`
Controller part (Slim3)
`$output = new CallbackStream(function () use ($request) {
for ($i=0; $i<10; $i++) {
$time = date('r');
echo "data: The server time is: {$time}\n\n";
ob_flush();
flush();
sleep(2);
}
echo "data: END\n\n";
ob_flush();
flush();
return '';
});
return (new Response())
->withHeader('Content-Type', 'text/event-stream')
->withHeader('Cache-Control', 'no-cache')
->withBody($output);`
CallbackStream helper class
[code]\