I had my car door open ready to exit my car, there were no operating cars on the road at the time, so because it was raining I was reaching for my umbrella. My girlfriend was in the passenger. When I turned to grab my umbrella a driver hit my car door. They had a clear lane to go around from the opposite direction, so who is at fault. Considering I took all the necessary precautions to make sure the coast was clear prior to opening the door and the other driver had time to see my car door open, considering I was close to the corner and they were heading the same direction. Who is at fault?

If you were parked and you didn't open the door in the path of the car they are.

Yes my car was parked, and when I opened the door, there were no operating cars on the road. It's a two way street and I made sure that there were no coming traffic.

But you should still report this to your insurer and then file a claim against the other driver's insurer.