Check response time of a website with ajax

ajax, javascript, jquery

Solution

The code itself is fine assuming that the code is running on the same origin as the one it's checking; you can't use ajax cross-origin unless both ends (client and server) support and are using CORS.

It could be caching, yes, you'd have to refer to the browser tools (any decent browser has a Network tab or similar in its developer tools) to know for sure. You can also disable caching by setting `cache: false` in the `ajax` call (see the `ajax` documentation for details), although that's a somewhat synthetic way to do it. A better way would be to ensure that whatever URL you're using for this timing responds with cache headers telling the browser (and proxies) not to cache it.

You can tell if the page doesn't exist or is "unavailable" (whatever that means) by hooking the `error` function and looking at the information it gives you:

var start = new Date();
$.ajax ({
    url: 'http://www.example.com',
    error : function(jqxhr, status, ex) {
        // Look at status here
    },
    complete : function()
    {
        alert(new Date() - start)
    },
}); 

The arguments given to `error` are also described in the docs linked above.

Problem

Original source