django AttributeError: dict object has no attribute 'pk'

Question

I'm making a simple django rest framework project. This is just creating a new user, and logging in. When I used django basic auth user model, everything worked well. But after changing basic user model to custom user, this error comes out when creating a new user:

dict object has no attribute 'pk'

Custom user model is made referred to django docs.

Error says that:

File "/home/seokchan/server/mdocker/lib/python3.5/site-packages/django/contrib/auth/__init__.py",
line 100, in login
    if _get_user_session_key(request) != user.pk or ( AttributeError: 'dict' object has no attribute 'pk'

This seems to say that user model has no pk, but I don't get it.

models.py

class MyUserManager(BaseUserManager):
        def create_user(self, username, email, password=None):

        if not email:
            raise ValueError('Users must have an email address')
        if not username:
            raise ValueError('Users must have an user name')

        user = self.model(
            email=self.normalize_email(email),
            username = username
        )

        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, username, email, password):

        user = self.create_user(
            username,
            password=password,
            email = email,
        )
        user.is_admin = True
        user.save(using=self._db)
        return user


class MyUser(AbstractBaseUser):
    id          = models.AutoField(primary_key=True)

    username = models.CharField(
        verbose_name='user name',
        max_length=30,
        unique=True,
    )

    email = models.EmailField(
        verbose_name='email address',
        max_length=255,
        unique=True,
    )

    is_active = models.BooleanField(default=True)
    is_admin = models.BooleanField(default=False)

    sth_test = models.TextField(blank = True)

    objects = MyUserManager()

    USERNAME_FIELD = 'username'
    REQUIRED_FIELDS = ['email']

    def __str__(self):
        return self.username

    def has_perm(self, perm, obj=None):
        "Does the user have a specific permission?"
        # Simplest possible answer: Yes, always
        return True

    def has_module_perms(self, app_label):
        "Does the user have permissions to view the app `app_label`?"
        # Simplest possible answer: Yes, always
        return True

    @property
    def is_staff(self):
        "Is the user a member of staff?"
        # Simplest possible answer: All admins are staff
        return self.is_admin

serializers.py

class CreateUserSerializer(serializers.ModelSerializer):
    class Meta:
        model = get_user_model
        fields = ('id', 'username', 'email', 'password', 'is_active')

    email = serializers.EmailField(
                required=True,
                validators=[UniqueValidator(queryset=User.objects.all())]
            )
    username = serializers.CharField(
                max_length=32,
                validators=[UniqueValidator(queryset=User.objects.all())]
            )
    password = serializers.CharField(min_length=8, write_only=True)

    def validate_email(self,value):
        if User.objects.filter(email=value).exists():
            raise serializers.ValidationError("err.")
        return value

    def create(self, validated_data):
        user = User.objects.create_user(
            validated_data['username'],
            validated_data['email'],
            validated_data['password'],
            )
        user.is_active = False
        user.save()


message=render_to_string('accounts/account_activate_email.html',{
            'user':user,
            'domain':'localhost:8000/api/accounts/activate', 
            'uid':urlsafe_base64_encode(force_bytes(user.pk)).decode('utf-8'),  
            'token':account_activation_token.make_token(user)  
        })

        mail_subject = 'Bplus'
        to_email = user.email 
        AuthEmail = EmailMessage(mail_subject, message, to=[to_email]) 
        AuthEmail.send()

        return validated_data

views.py

class UserCreateAPI(generics.GenericAPIView):
    serializer_class = CreateUserSerializer

    def post(self, request, *args, **kwargs):
        if len(request.data["username"]) < 4 or len(request.data["password"]) < 8:
            body = {"message":"short field"}
            return Response(body, status = 400) 

        serializer = self.get_serializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        user = serializer.save()
        user_for_auth = User.objects.get(username=user['username'])  
        login(request, user)

        return Response(
            {
                "user":UserSerializer(
                    user, context=self.get_serializer_context()
                ).data,
                "token":AuthToken.objects.create(user_for_auth),
            }  
        )

How can I fix this error?

Answer 1

Your serializer create method returns the validated data instead of the created object. Since that is a dict, that is what you end up passing to the login function.

You should have return user instead of return validated_data.