[rest_framework serializer] a sample of class definitition #tags: django, rest_framework, serializer, class

class_serializer.py

# simple class with no models mappings
class LayerAuthSerializer(serializers.Serializer):
    nonce = serializers.CharField()
    display_name = serializers.CharField(required=False)
    avatar_url=serializers.CharField(required=False)
    

# a complex class definition
class CreateUserSerializer(serializers.Serializer):
	"""
	Serializer for create user request
	"""
	email = serializers.CharField(required=True)
	password = serializers.CharField(required=True) 
	gravatar_url = serializers.CharField(required=False) 

	def create(self, validated_data):
		# if user has used this number previously to authenticate,
		# then change validation code and and set number as validated = false  
		user = User.objects.create_user(email=validated_data['email'], password=validated_data['password'])

		# we detect if user has a profile picture from gravatar
		gravatar_url = validated_data.pop('gravatar_url', None)
		if gravatar_url is not None:
			photo = download_gravatar(gravatar_url)
			user.profile_avatar = photo
			user.save()
		return user

	def to_internal_value(self, data):
		super(CreateUserSerializer, self).to_internal_value(data)
		if not data.get('password'):
			raise serializers.ValidationError({
                'error': 'Password is required',
                'code' : exception_handler.ERROR_DATA_INCONSISTENCY
            })
		email = data.get('email')
		if not email:
			raise serializers.ValidationError({
	            'error': 'Email is required',
	            'code' : exception_handler.ERROR_DATA_INCONSISTENCY
		        })

		return data

 # custom field serializer
from django.contrib.auth.models import User
from django.utils.timezone import now
from rest_framework import serializers

class UserSerializer(serializers.ModelSerializer):
    days_since_joined = serializers.SerializerMethodField()

    class Meta:
        model = User

    def get_days_since_joined(self, obj):
        return (now() - obj.date_joined).days
      

 # custom field serializer with class
class ColorField(serializers.Field):
    """
    Color objects are serialized into 'rgb(#, #, #)' notation.
    """
    def to_representation(self, obj):
        return "rgb(%d, %d, %d)" % (obj.red, obj.green, obj.blue)

    def to_internal_value(self, data):
        data = data.strip('rgb(').rstrip(')')
        red, green, blue = [int(col) for col in data.split(',')]
        return Color(red, green, blue)