Test file write in rails application

I am developing a rails API application for an iphone app. Some of the endpoints lead to functions that write data into a file and stores it in a directory. Everything works fine but every time I run a test for one of these specific endpoints a file is written. Is it possible to get the file to automatically be removed once the test is complete?

More info: I am using RSpec with shoulda_matchers and FactoryGirl in case it is any use.