I'm writing an app that has to take products from a database and export them to several different online marketplaces (Amazon, Play, etc.). I want to apply different rules about whether to include products, and how to price them, based on things like which supplier a product comes from, which market it's going to, and what category it's in..

I thought maybe there might be some kind of design pattern that deals with this kind of situation. I want to design something that's going to make it easy to add new rules later on. Does anyone have any thoughts about the best way to do this?