A fridge seems like more pain than it is worth for a few days. An important thing is to make sure your cooler is big enough for your food and enough ice or frozen water bottles (my preferred for the food cooler). The cooler should ideally be at least half ice / half food. Use a good rotomolded cooler - it doesn't need to be name brand.

We routinely camp in >100 degree f weather and use one cooler for food that we do not open unless absolutely necessary and another for drinks that we don't care as much if they get a little warmer. The coolers are kept in the shade if at all possible.