I am making a web dashboard and for this I have a javascript function that loops infinitely, updating a particular div at frequent intervals. (it uses ajax/jquery to do this).
I have used a loop with setTimeout:
<!doctype html>
<html>
<head>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.5/jquery.min.js"></script>
<script type="text/javascript" language="javascript">
function updateMain() {
setTimeout(function() {
console.log("updating");
$('#main').load('new-content.php #main', function() {});
updateMain();
}, 3000)
}
updateMain();
</script>
</head>
<body>
<div id="main">
<p>hi there</p>
</div>
</body>
</html>
'new-content.php' is a file that is constantly updated by another part of my program, to show the new content for the dashboard. it looks something like this:
<div id="main">
<p>Hello i am updated content</p>
</div>
I am sure the loop is working as the "updating" messages appear at regular intervals in the console.
When the program starts, the div is showing "hello there", and in the new-content.php file it has "hello am updated content".
The first time the loop runs, it updates the div to show "hello i am updated content".
But if I further update the new-content.php file, for example to say "hello I am further updated content", it just won't show on my webpage. However I am sure that the loop is still running as the messages appear in console.
It's like ajax has some cached version of the new-content.php file that it loads at the start then keeps using forever.
I am very confused, if you could help me I would be very grateful
Thank you
PS: if it is of relevance, the website is running through flask but I don't think this is the problem.
EDIT: I believe it is actually a flask caching issue
You can try adding a cache buster to see if that helps. Change your code as follows:
function updateMain() {
setTimeout(function() {
console.log("updating");
const cb = new Date().getTime();
$('#main').load('new-content.php?cb=' + cb + '#main',function() {
updateMain();
});
}, 3000)
}
updateMain();
Wasn't able to solve the issue but for anyone who is trying to make a similar project, I decided to use flask-socketio instead which allows me to send data to javascript to be shown on the page, instead of javascript loading the data itself from a file. (the answer by vladtn on this SO post was useful as an introduction to socketio)