Handle multiparts (for file upload) in Express

I want to upload a file to my Express application. I can access the uploaded file using request.files.MYFILE in a function uploadFile, but my problem is that uploadFile is called only when the file have been entirely uploaded so I can't -for example- get the amount of bytes received until the upload is finished.

Is there a way to manage multipart easily in express or should I use node-formidable directly ?

I don't think express supports it out of the box, but... You could modify connect/multipart module (http://www.senchalabs.org/connect/multipart.html) and add something like:

form.onPart = function(part) {
 //
}

it should allow you to access stream (more info: https://github.com/felixge/node-formidable).