Liferay Yubikey OTP Login

I bought a Yubikey 4 last fall but didn’t have time to play with it until now. Yubikey is awesome and quite cheap USB authentication key. It also support FIDO U2F in addition to one-time-password. So far I’ve enabled on my Facebook account as well as MacOS Sierra login.  I also wanted to write some code and integrate it with Liferay. As a result I’ve implemented a simple Yubikey OTP login. More