How can I implement auto-save using time-interval with form that does an HTTP post?

I have a web application that posts a form to a Node.js webservice:

...method="post" action="/kudosapi/report"...

Now I need to implement an auto-save feature on this form. I can work out how to detect changes, etc., but what I'm not sure about is how (or IF) I can leverage this same HTML form action.

In the current design, once the user clicks a [Save] button, the form is submitted and the Node.js service redirects them back to another, i.e., the main, screen (this page is an editor).

My first instinct was to pass a parameter in the form to let the service know that's being auto-saved so it would not do the re-direct but I'm not sure that's sufficient.

Suggestions now how I can do this w/o completely rewriting the form/API?

Thanks!

Solution

What you need to know in this case is that there is a difference in how you can POST data from the client: you can do it synchronously or asynchronously. Sending a POST in an asynchronous way is what you want to do here, and you can do that with an ajax request the likes of:

$.ajax( {
  method : "POST" ,
  url    : "/kudosapi/report" ,
  [ .. ]
} );