External Authentication and creating new users on login

[cameronwilson99]

The sftpgo documentation makes mention of this:
If authentication succeeds the HTTP response code must be 200 and the response body can be:

• a valid SFTPGo user serialized as JSON. The user will be added/updated within the defined data provider
• empty, the existing SFTPGo user does not need to be updated. Please note that in versions 2.0.x and earlier an empty response was interpreted as an authentication error

I'm trying to get this to work, and so far I can log in with an existing user, but I am getting invalid credentials errors when the user does not yet exist in sftpgo. What fields are required to return for the server to use?

const sftpgoUser = {
  status: 1,
  username: username,
  password: passwordHash,
  home_dir: `/srv/sftpgo/data/${username}`,
  permissions: {
      "/": ["list", "download", "upload", "delete", "rename"]
  },
  groups: ["testgroup"],
}

const userExists = req.body.user
if (userExists) {
  return res.status(200).send();
} else {
  return res.status(200).json(sftpgoUser);
}