Upload fail

gistfile1.txt

    app.use(function (req, res, next) {
        var files = req.files;

        if (req.method.toLowerCase() === 'post' && req.user && files) {// only for logged in users
            var counter = 0;
            for (var file in files) {
                counter++;
                var filename = Math.random().toString(16).substr(2) + Date.now().toString(16);
                filename += '.' + files[file].name.split('.').pop();
                fs.rename(files[file].path, __dirname + '/public/uploads/' + filename, (function (file, filename) {
                    return function (err) {
                        if (err) {
                            console.log(err);
                        } else {
                            req.body[file] = filename;
                        }
                        if (!--counter) {
                            next();
                        }
                    }
                }(file, filename)));
            }
        } else {
            next();
        }
    });