node mmmagic detectFile returns inode/x-empty

Question

I am trying to detect my uploaded file type. There are two files im uploading:

input.xls

And

input.ods

In node i run the following code:

var magic = new Magic(mmm.MAGIC_MIME_TYPE);
magic.detectFile(req.filePath, function(err, result) {
    if (err) {
        waterfallCallback(customError.invalidInputMessage('File not uploaded'));
        return;
    }

    var fileType;
    var error;
    switch(result) {
        case 'text/plain':
        case 'text/csv':
        case 'application/csv':
            fileType = 'csv';
            break;
        case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
        case 'application/vnd.ms-excel':
            fileType = 'excel';
            break;
        case 'application/vnd.ms-office':
            error = customError.invalidInputMessage('Fileformat not supported');
            break;
        case 'application/vnd.oasis.opendocument.spreadsheet':
            fileType = 'ods';
            break;
        default:
            error = customError.invalidInputMessage('Only xlsx, xls and csv file types are supported');
            return;
    }

    waterfallCallback(error, fileType);
});

Debugging this code says that the file type is :

inode/x-empty

Can anyone tell me why this is happening?