How to implement an ajax request queue using jQuery

Question

What is the best way to implement an Ajax request queue using jQuery? Specifically, I want to accomplish the following:

A user triggers any number of Ajax requests within a web page, which need to be queued up and submitted sequentially.
The web page needs to receive responses from the server and adjust itself accordingly.
Finally, if an error occurs (connection lost, server failed to respond, etc.), I want jQuery to invoke a JavaScript function.

I'm struggling with the last requirement in particular, as the error handling mechanism in jQuery's Ajax functions is not very intuitive. Are there any examples/tutorials that could help me with this task?

Thanks!

You might like this: http://www.erichynds.com/jquery/using-deferreds-in-jquery/ — Mike Robinson, Apr 08 '11 at 21:54

score 2 · Accepted Answer · edited May 23 '17 at 11:47

2

I've made a few buffers like this. Some examples can be found simple task Buffer and deferred item queue.

As for error handling you can always use .ajaxError

edited May 23 '17 at 11:47

Community

1
1

answered Apr 08 '11 at 21:58

Raynos

166,823
56
351
396

Thanks, these look promising! – Tony the Pony Apr 08 '11 at 22:00
@Jen if you use node on the server, think about using socket.io or now ;) – Raynos Apr 08 '11 at 22:16

score 1 · Answer 2 · answered Apr 08 '11 at 21:56

jQuery ajax has an error attribute where you can attach a function and the method will only fire if an error occurs. See the below example:

jQuery.ajax({
            type: "POST",
            url: "url",
            dataType:"json",
            data:{},
            success:function(data){                    
                alert("Succeed!");
            },
            error:function (xhr, ajaxOptions, thrownError){
                alert(xhr.status);
                alert(thrownError);
            }    
        });

I hope you find this helpful.

Thanks! I've tried these error handlers before, but found their behavior quite unpredictable. I would get a *success* indication even if the connection was lost... — Tony the Pony, Apr 08 '11 at 21:59

How to implement an ajax request queue using jQuery

2 Answers2

Linked