node.js Upload file formidable

app.js

/**
 * Module dependencies.
 */

var express = require('express')
 , routes = require('./routes')
 , stylus = require('stylus')
  , util = require('util')
	//,	form = require('connect-form')
	,	formidable = require('formidable')
	, sys = require('sys')
	;

var app = module.exports = express.createServer(
);

// Configuration

function compile(str, path){
  return stylus(str)
    //.import(__dirname + '/public/stylesheets/cruz-azul')
    .set('filename', path)
    .set('warn', true)
    .set('compress', true);
};

app.configure(function(){
  app.set('views', __dirname + '/views');
  app.set('view engine', 'jade');
  app.use(express.bodyParser());
  app.use(express.methodOverride());
  app.use(require('stylus').middleware({ src: __dirname + '/public', compile: compile }));
  app.use(app.router);
  app.use(express.static(__dirname + '/public'));
});

app.configure('development', function(){
  app.use(express.errorHandler({ dumpExceptions: true, showStack: true })); 
});

app.configure('production', function(){
  app.use(express.errorHandler()); 
});

//console.log('hola, esto trae sucursalprovider:', SucursalProvider);

// Routes


app.get('/upload-file', function(req, res){
	res.send(
           '<form action="/upload-file" enctype="multipart/form-data" method="post">'+
      '<input type="text" name="title"><br>'+
      '<input type="file" name="upload" multiple="multiple"><br>'+
      '<input type="submit" value="Upload">'+
      '</form>'

        );
        res.end();
});

app.post('/upload-file', function(req, res, next){
	var form = new formidable.IncomingForm(),
		fields = [],files=[];
                 form.uploadDir = './uploads';

	form
		.on('error', function(err){
			res.writeHead(200, {'content-type':'text/plain'});
			res.end('error:\n\n'+util.inspect(err));
		})
		.on('field', function(field, value){
			console.log(field, value);
			fields.push([field, value]);
		})
                .on('file', function(field, file) {
                    console.log(field, file);
                    files.push([field, file]);
                })
		.on('end', function(){
			console.log('-> post done');
			res.writeHead('200', {'content-type':'text/plain'});
			res.end('received fields:\n\n'+util.inspect(fields) +'\n\n received files: ' + util.inspect(files));
		});
	console.log(req);
	form.parse(req);
});

app.listen(3000);
console.log("Express server listening on port %d in %s mode", app.address().port, app.settings.env);

No no actua de esa forma, lo sube directamente a la carpeta especificada, lo único que se me viene a la mente es que no existe el directorio uploads o que no tienes permisos para escribir en la carpeta, trata de hacer sudo chown -R $USER ./uploads dentro del directorio del server (para asignarte propietario del directorio), luego imprimi la cadena form: console.log(form) justo luego de haber definido el form.uploadDir y debe de imprimir algo como esto:

{ error: null,
  ended: false,
  maxFieldsSize: 2097152,
  keepExtensions: false,
  uploadDir: './uploads',
  encoding: 'utf-8',
  headers: null,
  type: null,
  bytesReceived: null,
  bytesExpected: null,
  _parser: null,
  _flushing: 0,
  _fieldsSize: 0 }

Ahí podes ver si realmente te esta pasando el parámetro.

Ya encontre por que, en la linea 31, se configura app.use(express.bodyParser());, si comento esta linea ya funciona, ahora a buscar el por que!, Gracias por tu ayuda.