This is the lock that Im using: http://www.ebay.com/itm/12V-Electromagnetic-Door-Locks-Magne... . Its electromagnetic and not a turn lock.
And the actuator that I built to control the lock is something like this: https://www.tindie.com/products/Armtronix/wifi-esp8266-solid...
The callback script in the dhcp server pushes an event to a mqtt broker on dhcp commit event.
And all of these orchestrated by home-assistant.io, on top of which, we have also mobile and voice (alexa) integration too.