Django REST Framework: how to cache the result of SerializerMethodField?

Question

I have a SerializerMethodField that make some heavy computation. I also use the same method into another SerializerMethodField of the same serializer. How can I cache the result of the first one, so I run only once the heavy computation?

Answer 1

Since the computation is common between two methods of the same serializer, you can use the cached_property decorator. This will cache the result of the method on the model instance, and the result will persist as long as the instance does.

from django.utils.functional import cached_property

class Person(models.Model):

    @cached_property
    def friends(self):
        ...