Django - Ajax HttpResponse delay

Question

I have a django view function that calls another function if a condition is true, the function is called as a separate process, the view returns a status variable which shows if the function was called or not, the status is returned to a ajax click event assigned to a button.
The problem is that when the function 'do_work' is executed ajax success function isn't run until 'do_work' terminates.

view function /update/

if condition:
        p = Process(target=do_work, args(pack,))
        p.daemon = True
        p.start()
        success = "True"
else:
        success = "False"
print success
return HttpResponse(success)

Ajax call

 $('button.update').click(function() {
                id = $(this).attr('id');
                $.post("/update/", {
                pack : id,
                }, function(result){
                    alert(result);
                    });
                return false;
                });

the 'print success' gets executed right away in both cases, but the alert wont pop up until the function do_woks terminates

Answer 1

What do you need in this? Can you be a bit more specific? Of course your AJAX call will not show an alert until do_work terminates. That's how any web interaction takes place...

Be more specific -

1. What are you doing?
2. What does "do_work()" do (List the code)?
3. Does do_work() work independently?
4. Why do you need to run it as a separate process?

UPDATE: OK this is what might be happening. You spawn a process. The parent process does not wait for the child process to terminate. After the child gets spawned, the parent process continues with the execution. Try adding p.join() after p.start(). That should make the parent process wait until the child process terminates & execute the flow only once.

P.S: Still curious as to why you need to spawn a child process as part of normal runtime execution? Process creation is an overhead!

Answer 2

Although you see the printed message before you return HttpResponse(success), that return statement in itself can't asynchronously finish the response.

Presumably after that function returns, your web server is still waiting for something else to happen (such as for all child processes to terminate) before it finishes the response.

For asynchronous tasks in Django I highly recommend Celery.