Create an instance from serializer without persisting it to db

Question

Working in the context of creating a django model:

# Creates potato and saves a row to db
spud = Potato.objects.create(...)

# Also creates a potato instance, but doesn't hit db yet.
# Could call `spud.save()` later if/when we want that.
spud = Potato(...)

In factory boy we also have an analogy for this Djangoism

# Returns a saved instance
spud = PotatoFactory.create()

# Returns an instance that's not saved
spud = PotatoFactory.build()

In rest framework v3.3.2, I can't find the analogy. Is it possible?

serializer = PotatoSerializer(data=...)

# creates the instance and saves in db
serializer.create(serializer.validated_data)

I can write my own, something like this:

class PotatoSerializer:
    ...
    def build(self, validated_data):
        return self.Meta.model(**validated_data)

But it's a drag not to have it on the base serializer, am I missing something?

Answer 1

Default Serializer do save to the database. However, if you want to test against the validation, a simple call to is_valid will do and avoid saving to the database.

I'm mostly guessing as your question isn't very clear regarding your goal.