A couple of years ago I wrote a set of utility classes (which inherit from Serializer and ViewSet) which "solve" this problem by inspecting serializers at the beginning of the request and figuring out what to pass to `select_related` and `prefetch_related` "automatically". It supports nested serializers, N-N, etc. Also lets you "help it" by saying "assume attribute X of a serializer accesses fields X,Y,Z of its object", for more "sophisticated" cases.
It's a very messy piece of code but it has survived many projects since I first wrote it 6 years ago. The day I enabled it at a previous job, we reduced a page load from 20s to 800ms or so just with it.
Huh, ran into same issue on a rails project; queries kicked off in inside serializes were a weed. We toyed with throwing errors if a query was made during serialization.
On top of that, everything about serialization is terribly slow in Rails :|
It's a very messy piece of code but it has survived many projects since I first wrote it 6 years ago. The day I enabled it at a previous job, we reduced a page load from 20s to 800ms or so just with it.