Water Leakage Sensor on ESP8266 + Micropython + Domoticz

Some time ago, my wife asked me to make a water leakage sensor. She was afraid that the hose in the boiler room can be leaky, and the water would flood the newly laid wooden floor. And I as a true engineer undertook such a sensor to do.
From my 15 years of experience as an medical engineer, I know that easiest way of detecting water is metal pins shorted by water. The principle of operation of the simplest sensors is that water has to short two (or more) metal pins, and as soon as it happens, alarm triggers.”