Django restframework user email already exists error

Question

I am trying to write a login view in django restframe work to authenticate a user into the application but each time I send a request to the server I keep getting this error

`{ 'email': ['email already exist'] }``

here is how I wrote my login serializer

class UserLoginSerializer(serializers.ModelSerializer):
    full_name: str = serializers.CharField(source='get_name', read_only=True)
    tokens: str  = serializers.CharField(source='get_token', read_only=True)
    class Meta:
        model = User
        fields = (
            'id',
            'full_name',
            'email',
            'password',
            'is_superuser',
            'is_seller',
            'created_at',
            'profile_pic',
            'tokens' 
        )
        extra_kwargs = {
            'password' : {'write_only':True, 'required': True},
            'id': {'read_only': True},
            'is_superuser': {'read_only': True},
            'is_seller': {'read_only': True},
            'created_at': {'read_only': True},
            'profile_pic': {'read_only': True}
        }

    def validate(self, data: dict) -> dict:
        email: str = data.get('email', '')
        password: str = data.get('password', '')
        print(password, email) 
        user: auth = auth.authenticate(email=email, password=password)
        print(user)
            
        data = {
            'email': user.email,
            'tokens': user.get_token()
        } 
        return data

and here is how I wrote my loginapiview


class UserLoginAPIView(generics.GenericAPIView):
    serializer_class = UserLoginSerializer

    def post(self, request):
        serializer = self.serializer_class(data=request.data)
        serializer.is_valid(raise_exception=True)
        return Response(serializer.data, status=status.HTTP_200_OK)

what is your authentication backend?

Amin Basiri
– Amin Basiri

2024-04-22 07:09:37 +00:00
Commented Apr 22, 2024 at 7:09 — Amin Basiri
– Amin Basiri, Commented Apr 22, 2024 at 7:09

Nealium · Accepted Answer · 2024-04-22 00:29:49Z

1

My assumption is it is because you are using a ModelSerializer, so the built in email validator is checking as if it's a create call

This is my Email User Serializer, shamelessly ripped and edited from rest_framework.authtoken.serializers.AuthTokenSerializer. It's slightly different from yours as it's returning user in validated_data instead of returning it directly from the validate function, so there's a bit extra inside the view.

from django.contrib.auth import authenticate
from rest_framework import serializers
from django.utils.translation import gettext_lazy as _

class EmailUserLoginSerializer(serializers.Serializer):
    """Email login"""

    email = serializers.CharField(label=_("email"), write_only=True)
    password = serializers.CharField(
        label=_("Password"),
        style={"input_type": "password"},
        trim_whitespace=False,
        write_only=True,
    )
    token = serializers.CharField(label=_("Token"), read_only=True)

    def validate(self, attrs):
        """Validate"""
        email = attrs.get("email")
        password = attrs.get("password")

        if email and password:
            user = authenticate(
                request=self.context.get("request"),
                email=email,
                password=password,
            )

            # The authenticate call simply returns None for is_active=False
            # users. (Assuming the default ModelBackend authentication
            # backend.)
            if not user:
                msg = _("Unable to log in with provided credentials.")
                raise serializers.ValidationError(msg, code="authorization")
        else:
            msg = _('Must include "email" and "password".')
            raise serializers.ValidationError(msg, code="authorization")

        attrs["user"] = user
        return attrs

class UserLoginAPIView(generics.GenericAPIView):
    serializer_class = EmailUserLoginSerializer

    def post(self, request):
        serializer = self.serializer_class(data=request.data)
        serializer.is_valid(raise_exception=True)
        user = serializer.validated_data["user"]
        # Note: No need for status=status.HTTP_200_OK as that's the default!
        return Response({
            "email": user.email,
            "tokens": user.get_token(),
        })

answered Apr 22, 2024 at 0:29

Nealium

2,2781 gold badge9 silver badges12 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

kelani darasimi Over a year ago

but why do we need to pass the request into authenticate

Nealium Over a year ago

@kelanidarasimi In this specific situation you don't really have to, as you're using the default django auth, See: django.contrib.auth.backends.ModelBackend authenticate.

Nealium Over a year ago

@kelanidarasimi But looking at some of the django-rest-framework authentication functions, example: rest_framework.authentication.BasicAuthentication authenticate, they do use the request to rip out the header. sooo, up to you to keep it. imo it's not hurting anybody and the default django auth as it as an argument, so why not?

BRIJESH · Accepted Answer · 2024-04-22 00:55:16Z

1

Because you mention a email field in UserLoginSerializer. So email is required in a post request body otherwise serializer through an error.

answered Apr 22, 2024 at 0:55

BRIJESH

113 bronze badges

1 Comment

Community Over a year ago

As it’s currently written, your answer is unclear. Please edit to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center.

Collectives™ on Stack Overflow

Django restframework user email already exists error

2 Answers 2

3 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related