Django REST nested objects validate - django

Question

My database:
User
-----------------------------------
id | name
-----------------------------------
1 | Phuong Vu
-----------------------------------
Profile
-----------------------------------
user_id | phone_number
-----------------------------------
1 | 123456
-----------------------------------
My models:
class User(models.Model):
id = models.AutoField(primary_key=True)
name = models.CharField(max_length=100)
class Profile(models.Model):
user = models.OneToOneField(User, primary_key=True)
phone_number = models.CharField(max_length=15, unique=True, blank=True)
My serializers:
class ProfileSerializer(serializers.ModelSerializer):
def validate(self, attrs):
##################################
# I want get current instance here
##################################
print self.instance
return attrs
class Meta:
model = Profile
class UserSerializer(serializers.ModelSerializer):
profile = ProfileSerializer(many=False)
class Meta:
model = User
This is in my view, I called is_valid 2 times in 2 ways to test:
profile_data = {
'phone_number':'123456'
}
user = User.objects.get(pk=1)
profile = Profile.objects.get(user_id=1)
setattr(user, 'profile', profile)
data = {
'profile': profile_data
}
serializer = UserSerializer(
user,
data=data,
partial=True
)
# This said 'Profile phone number is exist'
# because ProfileSerialiser.instance is None
serializer.is_valid()
# This is fine because ProfileSerialiser.instance is not None
profile_serialiser = ProfileSerialiser(profile, data=profile_data, partial=True)
profile_serializer.is_valid()
After create serializer instance, UserSerializer.instance is not None but children ProfileSerializer.instance is None.
So how can I fix this issue? (Access to self.instance in ProfileSerializer after it has created via UserSerialiser)