How to create an endpoint with an arbitrary request format, saving logic, and response format?

[Travis Miller]

I'm new to DRF (and pretty new to Django and Python in general). I'm trying to build a simple API endpoint. But I'm having trouble figuring out the best approach.

1. The endpoint accepts a request payload similar to the following (this is contrived):

{

    "employee_id": 123,

    "favorite_flavor": "chocolate",

    "subscribe_to_updates": true,

    "cats_or_dogs": "cats"

}

Obviously, I would like to validate this payload before doing anything further with it.

2. The endpoint then creates several related records in the database. Note that the request payload is not a direct 1-to-1 representation of a Django ORM model. Instead, employee_id gets saved to one table, and favorite_flavor and subscribe_to_updates get saved to a second table. Perhaps cats_or_dogs doesn't get saved to the database at all – maybe it just triggers an email send, or writes a file to disk, or something like that.

3. Finally, I would like the endpoint to return an arbitrary JSON payload, which differs from both the request payload and the model structure:

{

    "recommended_dessert": "Black Forest Cake",

    "subscription_id": 5827,

    "cat_name": "Fluffy",

    "some_nested_object": {

        "foo": "bar"

    }

}

How can I do this? DRF provides a dizzying array of ways to do things, and I can't quite figure out which combination is best for my case.

Thanks!

[Michael Angelozzi]

To override the returned representation, you can override the `to_representation` method of a serializer:

    def to_representation(self, instance):

        data = super().to_representation(instance)

        data.pop('secret_field')

        data['some_new_field'] = 'Cow infiltrator!'

        data['nested_data'] = {'fav_toys': ['pogo_stick', 'cannon balls']}

        return data

Nested serializers are handled as per the docs: https://www.django-rest-framework.org/api-guide/serializers/#specifying-nested-serialization

You can specify arbitary fields in your serializer with https://www.django-rest-framework.org/api-guide/serializers/#specifying-fields-explicitly

Or use a callable via a method field: https://www.django-rest-framework.org/api-guide/fields/#serializermethodfield

You don't live in South Africa by any chance?

Cheers!