If you are OK with that light always turning off 30 minutes after it was turned on during this long weekend, then it’s easy.
Use the official smart lighting app to set a “power allowance” on that light so that it always turns itself off after 30 minutes.
Then you create a second smart lighting rule to turn the light on when the door opens during the desired timeframe.
That should be all you need.
If you want it to only turn off after 30 minutes if it was turned on because of the door opening, but to stay on if it was turned on in some other fashion, see the how to article in the community – created wiki on creating a virtual timer:
That same article also explains how to use the power allowance feature if you aren’t familiar with that, just look at step two in the how to.
When you get home again, either remove those rules or change them to only run in a mode that you aren’t using.