Django user model username (unique=False)

Question

I have seen many of the solution but none of it seems to be answering the question.

My user model is using AbstractUser right now. Is there a way to make username(unique = False)

Since i wanted to allow user to ba able to have duplication of same username, as the login im am using is by email address and password

Below is the code that i tried but doesnt work.

Code:

class MyUser(AbstractUser):
    username = models.CharField(max_length=30, unique=False)

error:

customuser.MyUser: (auth.E003) 'MyUser.username' must be unique because it is named as the 'USERNAME_FI ELD'

Can this help with what you're trying to do: https://stackoverflow.com/questions/37332190/django-login-with-email? — bonidjukic, Feb 20 '18 at 09:38
@bonidjukic I already can login using email. I just need to make username unique = false. Thats it — Jin Nii Sama, Feb 20 '18 at 09:49
The code you have should work. Have you updated your settings to instruct Django to use your custom `User` model? — shad0w_wa1k3r, Feb 20 '18 at 09:54
`customuser.MyUser: (auth.E003) 'MyUser.username' must be unique because it is named as the 'USERNAME_FI ELD'.` This is the error i get — Jin Nii Sama, Feb 20 '18 at 09:57
You should add that error to your question, that would make it much more clear. — shad0w_wa1k3r, Feb 20 '18 at 09:59

score 3 · Answer 1 · answered Feb 16 '19 at 05:24

A non-unique username field is allowed if you use a custom authentication backend that can support it.

If you want to use django's default authentication backend you cannot make username non unique.

You will have to implement a class with get_user(user_id) and authenticate(request, **credentials) methods for a custom backend.

You can read it in the documentation here. https://docs.djangoproject.com/en/2.1/topics/auth/customizing/#specifying-custom-user-model

score 2 · Answer 2 · answered Feb 20 '18 at 10:00

2

Try to specify email as username field with USERNAME_FIELD attribute:

class MyUser(AbstractUser):
    username = models.CharField(max_length=30, unique=False)
    USERNAME_FIELD = 'email'

answered Feb 20 '18 at 10:00

neverwalkaloner

46,181
7
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then the unique=False would ruin the whole validation of unique email – Jin Nii Sama Feb 21 '18 at 02:51
email is a must to be unique, Just wanted to change username unique into false. – Jin Nii Sama Feb 21 '18 at 02:52

score 2 · Answer 3 · answered Feb 16 '19 at 05:07

2

class MyUser(AbstractUser):
    username = models.CharField(max_length=30, unique=False)
    email = models.EmailField(max_length=255, unique=True)
    USERNAME_FIELD = 'email'

answered Feb 16 '19 at 05:07

Nikhil Bhardwaj

562
10
18

Please explain a little about your answer. – Mehrdad Pedramfar Feb 16 '19 at 07:45
@MehrdadPedramfar I don't know about his code so I just want give some info related to his code and I don't want to add something additional in it..... And he is inheriting AbstractUser class so, that username field will directly make an impact on the Django username field.... This is it – Nikhil Bhardwaj Feb 16 '19 at 10:45

score 1 · Answer 4 · answered Mar 14 '23 at 16:51

It is possible, if a custom user class is used and with the authentication backend from Django itself:

Create a custom user class based on the Abstract User class:

 from django.contrib.auth.models import AbstractUser

 class CustomUser(AbstractUser):
     username = models.CharField(_("username"), max_length=254, unique=False)
     email = models.EmailField(_("email"), max_length=254, unique=True)

     USERNAME_FIELD = "email"
     REQUIRED_FIELDS = ["username"]

     objects = CustomUserManager()

     def __str__(self):
       return self.username

Create a Custom User Manager class, as described in: https://docs.djangoproject.com/en/4.1/topics/auth/customizing/#writing-a-manager-for-a-custom-user-model
Update the SQL database configuration by running in bash:
```
 manage.py makemigrations
 manage.py migrate
```

The username field now should be recognised as non-unique, while the email is the unique key identifier.

Hope this helps!

MK.

Django user model username (unique=False)

4 Answers4