How to get rid of fruit flies from compost?

http://www.davidsuzuki.org/what-you-can-do/queen-of-green/faqs/composting/how-to-prevent-of-fruit-flies/

Vinegar works great

I would cover it up, to avoid this problem. Sure needs a rest from the sun. Take care

Spray it with a vinegar and water mixture

Fill a microwave-safe bowl with apple cider vinegar and a few drops of dish soap. Microwave the bowl so the mixture becomes even more aromatic. Leave the bowl out uncovered as fruit fly bait. The soap will reduce the surface tension, causing any fruit fly that lands on the surface to drown. Now, if what you have might be drain flies...if that is what you have try this: Boil some water on the stove and pour down your drain several times a day for about a week or Mix 1/2 cup salt, 1/2 cup baking soda and 1 cup of vinegar and then pour the mixture down the drain, leaving it overnight. In the morning, pour boiling hot water down the drain.

If a drain fly infestation lasts longer than 20 days despite different approaches to get rid of them, then it’s time to call a professional exterminator.