[Answered ]-Django REST Framework after PUT/PATCH action

The post_save method on views exists exactly for this reason. The Django REST Framework documentation doesn’t cover it well, but it is a hook that is called with two arguments, obj (the object that was saved) and created (True for POST/PUT-as-create, False for PUT-as-update/PATCH).

You can get access to the sent data with self.request.DATA, which should allow you to modify saved objects to suit your needs.

post_save as mentioned before is now (>2.x) outdated (https://www.django-rest-framework.org/api-guide/generic-views/). The new functions to hook on generic views are:

perform_create(self, serializer)
perform_update(self, serializer)
perform_destroy(self, instance)