Django Rest Framework with ChoiceField

Question

I have a few fields in my user model that are choice fields and am trying to figure out how to best implement that into Django Rest Framework.

Below is some simplified code to show what I'm doing.

# models.py
class User(AbstractUser):
    GENDER_CHOICES = (
        ('M', 'Male'),
        ('F', 'Female'),
    )

    gender = models.CharField(max_length=1, choices=GENDER_CHOICES)


# serializers.py 
class UserSerializer(serializers.ModelSerializer):
    gender = serializers.CharField(source='get_gender_display')

    class Meta:
        model = User


# viewsets.py
class UserViewSet(viewsets.ModelViewSet):
    queryset = User.objects.all()
    serializer_class = UserSerializer

Essentially what I'm trying to do is to have the get/post/put methods use the display value of the choice field instead of the code, looking something like the below JSON.

{
  'username': 'newtestuser',
  'email': '[e-mail]',
  'first_name': 'first',
  'last_name': 'last',
  'gender': 'Male'
  // instead of 'gender': 'M'
}

How would I go about doing that? The above code does not work. Before I had something like this working for GET, but for POST/PUT it was giving me errors. I'm looking for general advice on how to do this, it seems like it would be something common, but I can't find examples. Either that or I'm doing something terribly wrong.

Answer 1

I suggest to use django-models-utils with a custom DRF serializer field

Code becomes:

# models.py
from model_utils import Choices

class User(AbstractUser):
    GENDER = Choices(
       ('M', 'Male'),
       ('F', 'Female'),
    )

    gender = models.CharField(max_length=1, choices=GENDER, default=GENDER.M)


# serializers.py 
from rest_framework import serializers

class ChoicesField(serializers.Field):
    def __init__(self, choices, **kwargs):
        self._choices = choices
        super(ChoicesField, self).__init__(**kwargs)

    def to_representation(self, obj):
        return self._choices[obj]

    def to_internal_value(self, data):
        return getattr(self._choices, data)

class UserSerializer(serializers.ModelSerializer):
    gender = ChoicesField(choices=User.GENDER)

    class Meta:
        model = User

# viewsets.py
class UserViewSet(viewsets.ModelViewSet):
    queryset = User.objects.all()
    serializer_class = UserSerializer