Join related models in django rest framework

Question

Trying to create an API method for getting user profile. The problem is that there are two tables related to user: built in django User and SocialAccount from allauth framework. I guess the joining part should be in serializers so after a research I came up with this:

from rest_framework import serializers
from django.contrib.auth.models import User
from allauth.socialaccount.models import SocialAccount


class UserSerializer(serializers.ModelSerializer):

    class Meta:
        model = User
        fields = ('pk', 'first_name', 'last_name')


class SocialSerializer(serializers.ModelSerializer):
    user = UserSerializer(many=False, read_only=True)

    class Meta:
        model = SocialAccount
        fields = ('uid', 'provider', 'user')

It works but it outputs it as nested objects:

{
  "uid": "",
  "provider": "",
  "user": {
    "pk": 5,
    "first_name": "",
    "last_name": ""
  }
}

I would like it to be as one object:

{
  "uid": "",
  "provider": "",
  "pk": 5,
  "first_name": "",
  "last_name": ""
}

Answer 1

You can either try to flatten the JSON (see this link) or redefine your serializer as below:

class SocialSerializer(serializers.ModelSerializer):
    pk = serializers.SerializerMethodField()
    first_name = serializers.SerializerMethodField()
    last_name = serializers.SerializerMethodField()

    class Meta:
        model = SocialAccount
        fields = ('uid', 'provider', 'pk', 'first_name', 'last_name')

    def get_pk(self, obj):
        return obj.user.pk

    def get_first_name(self, obj):
        return obj.user.first_name

    def get_last_name(self, obj):
        return obj.user.last_name

These are serializers.SerializermethodField() fields which will look at the get_<field_name> method and call them and use the returned value.

http://www.django-rest-framework.org/api-guide/fields/#serializermethodfield

Answer 2

alternatively, try

class SocialSerializer(serializers.ModelSerializer):
    user = UserSerializer()

    class Meta:
        model = SocialAccount
        fields = ('uid', 'provider', 'user')

    def to_representation(self, instance):
        data = super(SocialSerializer, self).to_representation(instance)
        user = data.pop('user')
        for key, val in user.items():
            data.update({key: val})
        return data