Data too long for column when creating user

Question

By going to

url(r'api/users/', views.MyUserCreate.as_view(), name='user-create'),

one can see DRF Browsable API

which uses MyUserCreate (in views.py)

class MyUserCreate(APIView):
    """ 
    Creates the user. 
    """

    def post(self, request, format='json'):
        serializer = MyUserSerializer(data=request.data)
        if serializer.is_valid():
            MyUser.objects.create_user(
                        serializer.username,
                        serializer.password
            )
            if user:
                return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors,status=status.HTTP_400_BAD_REQUEST)

Note that it references MyUserSerializer (in serializers.py)

class MyUserSerializer(serializers.ModelSerializer):
    username = serializers.CharField(
            required=True,
            validators=[UniqueValidator(queryset=MyUser.objects.all())],
            min_length=5,
            max_length=20
            ),
    password = make_password(serializers.CharField(
            write_only=True,
            required=True,
            max_length=256
            ))

    class Meta:
        model = MyUser
        fields = ('username', 'password')

    def create_user(self, validated_data):
        password = make_password(validated_data['password'])
        user = MyUser.objects.create_user(validated_data['username'], password)
        return user

and MyUser (in models.py)

class MyUserManager(BaseUserManager):
    def create_user(self, username, password):
        user = self.model(
            username=username
        )
        user.set_password(password)
        user.save(using=self._db)
        return user

class MyUser(AbstractBaseUser):
    objects = MyUserManager()
    class Meta:
        # managed = False
        db_table = 'user_entity'

    user_id = models.AutoField(primary_key=True, db_column='userId')
    username = models.CharField(db_column='username', unique=True, max_length=20)
    password = models.CharField(db_column='userPassword', max_length=256)

    USERNAME_FIELD = 'username'

    def __str__(self):
        return str(self.user_id) + " (%s)" % str(self.username)

When I post to create a user

{
    "username": "tiagoperes",
    "password": "test"
}

I get

django.db.utils.DataError: (1406, "Data too long for column 'username' at row 1")

Following information from other users, checked if the column is UTF8

and doesn't make sense to use TextField instead of CharField here.

JPG · Accepted Answer · 2020-05-30T14:09:25.570

You are passing serializer.username to create function, which is not the data you are passed via POST request, hence the error.
Change your method create_user(...), to create(...) in MyUserSerializer so that, DRF will handle the function when you call the .save() method from view. (which is the DRF way)

Change your view as,

class MyUserCreate(APIView):

    def post(self, request, format='json'):
        serializer = MyUserSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

as well as your serializer

class MyUserSerializer(serializers.ModelSerializer):
    # rest of your code

    def create(self, validated_data):
        password = make_password(validated_data['password'])
        user = MyUser.objects.create_user(validated_data['username'], password)
        return user

Data too long for column when creating user

1 Answers1