Django rest create different objects with serializer - django-rest-framework

Question

In my project I have created a custom User object with a one to one relation to a Profile object in order to isolate authentication fields.
Profile
class Profile(models.Model):
first_name = models.CharField(max_length=50)
last_name = models.CharField(max_length=50)
image = models.ImageField(default='/user_images/default.png', upload_to='user_images', blank=True, null=True)
def __str__(self):
return self.first_name + " " + self.last_name
User
class User(AbstractBaseUser, PermissionsMixin):
email = models.EmailField(unique=True)
profile = models.OneToOneField(Profile, related_name="user" ,on_delete=models.CASCADE, default=None, blank=True, null=True)
is_visible = models.BooleanField(default=True)
is_staff = models.BooleanField(default=False)
is_active = models.BooleanField(default=True)
date_joined = models.DateTimeField(default=timezone.now)
USERNAME_FIELD = 'email'
REQUIRED_FIELDS = []
objects = CustomUserManager()
def __str__(self):
return self.email
My problem now is that i want to create the Profile object with the same request of the User object
View
class CustomView(APIView):
permission_classes = (permissions.AllowAny,)
def post(self, request, format='json'):
serializer = CustomSerializer(data=request.data)
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
Serializer
class CustomSerializer(serializers.Serializer):
# User
email = serializers.EmailField(required=True)
password = serializers.CharField(min_length=8, write_only=True)
# Profile
first_name = serializers.CharField(max_length=50)
last_name = serializers.CharField(max_length=50)
image = serializers.ImageField(allow_null=True, max_length=100, required=False)
def create(self, validated_data):
profile = Profile.objects.create(
first_name = validated_data['first_name'],
last_name = validated_data['first_name'],
image = validated_data['image'],
)
user = User.objects.create(
email = validated_data['email'],
profile = profile
)
user.set_password(validated_data['password'])
user.save()
return user
Now in the database everything is created correctly but i receive this error
Got AttributeError when attempting to get a value for field
first_name on serializer CustomSerializer. The serializer field
might be named incorrectly and not match any attribute or key on the
User instance. Original exception text was: 'User' object has no
attribute 'first_name'.
I suppose this means that a serializer can only handle the creation of one model so i'm supposed to handle my case?
Thanks

Answer 1

I assume that your error comes from to_representation() and what you can do is to set write_only=True on first_name, last_name and image fields like this:
first_name = serializers.CharField(max_length=50, write_only=True)
However, a more clean solution would be to use ModelSerialzier for both User and Profile models. If you do so, you'll have something like:
class ProfileSerializer(serializers.ModelSerializer):
class Meta:
model = Profile
fields = ("id", "first_name", "last_name", "image")
class UserSerializer(serializers.ModelSerializer):
profile = ProfileSerializer()
class Meta:
model = User
fields = ("id", "email", "profile", [...])
def create(self, validated_data):
...