Cool plugin! If you are the author, would you be willing to share your experience of building the plugin to begin with? We don't have a publicly documented plugin API or anything, so I imagine you had to figure a lot of this out from reverse engineering and such.
Graylog has this out of the box since v2.0 and integrated with the authentication layer: <a href="https://www.graylog.org/blog/55-announcing-graylog-v2-0-ga" rel="nofollow">https://www.graylog.org/blog/55-announcing-graylog-v2-0-ga</a>