Long story short, I want to build an iron farm under a one block deep pool. I read from other questions that you need sky access but I didn't understand what specific parts need lighting and whether having water and glass above those areas means that they are not receiving skylight. I am playing Minecraft Java 1.12.2 so my farm is going to be in the old fashioned way (pre 1.14) and the update aquatic hasn't affected me either. So this is possible and is there a special way I have to build this? Thanks
In 1.12.2 valid village doors are those that have a different number of solid ground blocks in front and behind them that have full sky light access (sky light value 15). So you basically only need a door, a solid block in front or behind (not on the side) on the ground and a clear path to the sky above that.