Simple Solution to Rest Client NTLM

scratch.rb

require 'ntlm/http'
require 'rest-client'
require 'json'

# Quick monkey patch to rest client payloads since for some reason Net/NTLM insists on playing payload streams backwards.
class RestClient::Payload::Base
  def rewind
    @stream.rewind
  end
end

auth_proc = ->(req, _args){ req.ntlm_auth(username, domain, password)}
res = RestClient::Request.new(method: :post, url: url, payload: payload}, before_execution_proc: auth_proc ).execute
res