jquery ajax call not asynchronous

Question

I am fresh to jQuery\'s implementation of it\'s AJAX methods.

I have a simple setup that accesses two different pages, one which takes 10 seconds to complete (I have

Answer 1

I have discovered the cause of the javascript call hanging.

To prevent a race condition from occurring with user session data, PHP locks the data until one of two conditions occur.

1. The previously called PHP script calls session_write_close().

2. The previously called PHP script completes processing and implicitly calls session_write_close().

Following the logic that a call to the server that does not call session_start() should allow true asynchronous calls, I created a dummy PHP page that just spits out a simple string and called to that page every second while the 10 second script ran. It ran perfectly.

The solution came from reading this discussion on the symfony forums.

Answer 2

What about something like

I dropped the try catch's and made your setTimeout's to look like check_id = setTimeout(progressCheck, 1000);

function beginLogin(){
    var login_url = "http://example.com/home/loginScript";
    return $.ajax({
        url: login_url,
        success: function(data){
            $("#result_div").append('<pre>' + data + '</pre><hr/>');
            alert("finished");
        },
        error: function(a, b, c){
            console.log(a)
            console.log(b)
            console.log(c)
        }
    });
}

function progressCheck(){
    var check_url = "http://example.com/home/checkLoginProgress";
    var ajax = $.ajax({
        url: check_url,
        success: function(data){
            $("#progress_div").append('<pre>' + data + '</pre><hr/>');
        },
        error: function(a, b, c){
            console.log(a)
            console.log(b)
            console.log(c)
        }
    });

    check_id = setTimeout(progressCheck, 1000);
    return ajax;
}

// set progress checking function to call every second
var check_id = setTimeout(progressCheck, 1000);

function clearCheck(){
    try {
        clearTimeout(check_id);
    } catch (e) {
        alert("There was an error clearing the check: " + e);
        return false;
    }
    return true;
}