Imagine I asked you to build an API endpoint with name and id fields that looked like the following.

    "name": "William Vincent",
    "id": "v1.0-2018"

Do you see the issue? Using id is a problem since Django sets id to the primary key of a database entry by default, yet we need to output id representing a different value somehow. The answer is to use the source argument in Django Rest Framework’s serializer class.

Here’s what the and files would look like.

from django.db import models

class Person(models.Model):
    name = models.CharField(max_length=100)
    person_id = models.CharField(max_length=100)

from rest_framework import serializers
from . import models

class PersonSerializer(serializers.ModelSerializer):
    id = serializers.CharField(source='person_id')

    class Meta:
        model = models.Person
        fields = ('name', 'id',)

So the next time you need to override the outputted field name on a model, think first of your serializer and then of source.

Next Steps

Want to learn more about Django APIs? I’ve written an entire book on the subject called Django for APIs. The first two chapters are available to read for free.