Question

I have a single page that I need to on occasion asynchronously check the server to see if the status of the page is current (basically, Live or Offline). You will see I have a function with a var live that is set when the page initially loads. I then do an ajax request to the server to retrieve whether the status of live is true or false. I compare the initial live variable with the newly returned data json object. If they’re the same I do nothing, but if there different I apply some css classes. I recursively run it with setTimeout (Is there a better way to recursively do this?).

My Problem:
data.live doesn’t change from it’s initial time it runs even when it has changed in the db. I know my mysql is working because it returs the right value on the initial load. It seems like a caching issue.

Any help is greatly appreciated.

function checkLive() {
    var live = <?=$result["live"]?>;

    $.ajax({
        type: 'get',
        url: '/live/live.php',
        dataType: 'json',

        success: function(data) {
            console.log('checking for updates... current:' + data.live);
            if (data.live == live) {
                return;
            } else {
                var elems = $('div.player_meta, object, h3.offline_message');
                if (data.live == '1') {
                    elems.removeClass('offline').addClass('live');
                } else {
                    elems.addClass('live').addClass('offline');
                }
            }
        }
    });

    setTimeout(function() { checkLive() } ,15000);
} 

checkLive();

Answer 1

Use the cache option of $.ajax() to append a cache breaker to the URL, like this:

$.ajax({
    type: 'get',
    url: '/live/live.php',
    dataType: 'json',
    cache: false,
    //success, etc.
});

If that doesn’t resolve it…look at firebug, see if a request is being made (it should be after this for sure), if it’s still getting an old value, the issue is in PHP, not JavaScript.

---

Unrelated to the issue, just a side tip: If you need no parameters, you can skip the anonymous function call, this:

setTimeout(function() { checkLive() } ,15000);

can just be:

setTimeout(checkLive, 15000);