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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': 'newuser@email.com',
  '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.

Answers

An update for this thread, in the latest versions of DRF there is actually a ChoiceField.

So all you need to do if you want to return the display_name is to subclass ChoiceField to_representation method like this:

from django.contrib.auth import get_user_model
from rest_framework import serializers

User = get_user_model()

class ChoiceField(serializers.ChoiceField):

    def to_representation(self, obj):
        if obj == '' and self.allow_blank:
            return obj
        return self._choices[obj]

    def to_internal_value(self, data):
        # To support inserts with the value
        if data == '' and self.allow_blank:
            return ''

        for key, val in self._choices.items():
            if val == data:
                return key
        self.fail('invalid_choice', input=data)


class UserSerializer(serializers.ModelSerializer):
    gender = ChoiceField(choices=User.GENDER_CHOICES)

    class Meta:
        model = User

So there is no need to change the __init__ method or add any additional package.