Imagine I sell some products (e.g. books, games etc.) and each instance of particular product can have some tags. (So in JSON API I would probably model it as separate resources tags, books, games with M:N relationship between tags and all other resources. But I imagine it could get more complicated). Now the use case is:
Show me all products (of any type) having a) a given tag, b) at least one of given tags, c) all of given tags. Additional requirement is that each of the questions should be answered by single REST call.
Any recommendations how to model these use case (or at least a) in JSON API?