let handleUserLoginPromises = (data) => {
  let { username, password } = data

  let authenticate = (authType) =>
    app.requestUserAuth(authType)
      .then(authData => server.authenticate(authData).catch(handleNeedsAuth))

  let handleNeedsAuth = (err) => err.needsAuth
    ? authenticate(err.authType)
    : Promise.reject(err)

  return server.login(username, password).catch(handleNeedsAuth)
}