How to modify file after being uploaded to tus-node-server?

Question

I am using tus-node-server, I get the file id but when I modify the file, the url of this file is no longer working.

I found that there is a write function in the source code, but I am not sure how to use it to update the file

    /**
     * Write to the file, starting at the provided offset
     *
     * @param  {object} req http.incomingMessage
     * @param  {string} file_id   Name of file
     * @param  {integer} offset     starting offset
     * @return {Promise}
     */
    write(req, file_id, offset) {

I have file_id, but how do I send the new file content and should the offset be 0?

I just need a way to edit the files after being uploaded whether through the previous function or through any other method