Using Django auth UserAdmin for a custom user model

After digging around the Django source code for a while, I found a working soultion. I am not totally happy with this solution, but it seems to work. Feel free to suggest better solutions!

Django uses UserAdmin to render the nice admin look for User model. By just using this in our admin.py-file, we can get the same look for our model.

from django.contrib.auth.admin import UserAdmin
admin.site.register(MyUser, UserAdmin)

However, this alone is probably not a good solution, since Django Admin will not display any of your special fields. There are two reasons for this:

UserAdmin uses UserChangeForm as the form to be used when modifying the object, which in its turn uses User as its model.

UserAdmin defines a formsets-property, later used by UserChangeForm, which does not include your special fields.

So, I created a special change-form which overloads the Meta inner-class so that the change form uses the correct model. I also had to overload UserAdmin to add my special fields to the fieldset, which is the part of this solution I dislike a bit, since it looks a bit ugly. Feel free to suggest improvements!

from django.contrib.auth.admin import UserAdmin
from django.contrib.auth.forms import UserChangeForm

class MyUserChangeForm(UserChangeForm):
    class Meta(UserChangeForm.Meta):
        model = MyUser

class MyUserAdmin(UserAdmin):
    form = MyUserChangeForm

    fieldsets = UserAdmin.fieldsets + (
            (None, {'fields': ('some_extra_data',)}),
    )


admin.site.register(MyUser, MyUserAdmin)

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A simpler solution, admin.py:

from django.contrib.auth.admin import UserAdmin
from main.models import MyUser

class MyUserAdmin(UserAdmin):
    model = MyUser

    fieldsets = UserAdmin.fieldsets + (
            (None, {'fields': ('some_extra_data',)}),
    )

admin.site.register(MyUser, MyUserAdmin)

Django will correctly reference MyUser model for creation and modification. I'm using Django 1.6.2.

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nico's answer has been extremely helpful but I found Django still references the User model when creating a new user.

Ticket #19353 references this problem.

In order to fix it i had to make a few more additions to admin.py

admin.py:

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from django.contrib.auth.forms import UserChangeForm, UserCreationForm
from main.models import MyUser
from django import forms


class MyUserChangeForm(UserChangeForm):
    class Meta(UserChangeForm.Meta):
        model = MyUser


class MyUserCreationForm(UserCreationForm):
    class Meta(UserCreationForm.Meta):
        model = MyUser

    def clean_username(self):
        username = self.cleaned_data['username']
        try:
            MyUser.objects.get(username=username)
        except MyUser.DoesNotExist:
            return username
        raise forms.ValidationError(self.error_messages['duplicate_username'])


class MyUserAdmin(UserAdmin):
    form = MyUserChangeForm
    add_form = MyUserCreationForm
    fieldsets = UserAdmin.fieldsets + (
        (None, {'fields': ('extra_field1', 'extra_field2',)}),
    )

admin.site.register(MyUser, MyUserAdmin)

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cesc's answer wasn't working for me when I attempted to add a custom field to the creation form. Perhaps it's changed since 1.6.2? Either way, I found adding the field to both fieldsets and add_fieldsets did the trick.

ADDITIONAL_USER_FIELDS = (
    (None, {'fields': ('some_additional_field',)}),
)

class MyUserAdmin(UserAdmin):
    model = MyUser

    add_fieldsets = UserAdmin.add_fieldsets + ADDITIONAL_USER_FIELDS
    fieldsets = UserAdmin.fieldsets + ADDITIONAL_USER_FIELDS

admin.site.register(MyUser, MyUserAdmin)

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Another similar solution (Took from here):

from __future__ import unicode_literals

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from django.contrib.auth.models import AbstractUser
from django.utils.translation import ugettext_lazy as _

from .models import User


class UserAdminWithExtraFields(UserAdmin):

    def __init__(self, *args, **kwargs):
        super(UserAdminWithExtraFields, self).__init__(*args, **kwargs)

        abstract_fields = [field.name for field in AbstractUser._meta.fields]
        user_fields = [field.name for field in self.model._meta.fields]

        self.fieldsets += (
            (_('Extra fields'), {
                'fields': [
                    f for f in user_fields if (
                        f not in abstract_fields and
                        f != self.model._meta.pk.name
                    )
                ],
            }),
        )


admin.site.register(User, UserAdminWithExtraFields)

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If you want to hook into the default sections instead of copying and pasting Django core code, you can extend the UserAdmin class and inject your fields into the fieldsets attribute as wished.

In Django v4.0.x, the fieldsets tuple you are modifying looks like this:

    fieldsets = (
        (None, {"fields": ("username", "password")}),
        (_("Personal info"), {"fields": ("first_name", "last_name", "email")}),
        (
            _("Permissions"),
            {
                "fields": (
                    "is_active",
                    "is_staff",
                    "is_superuser",
                    "groups",
                    "user_permissions",
                ),
            },
        ),
        (_("Important dates"), {"fields": ("last_login", "date_joined")}),
    )

Source: https://github.com/django/django/blob/stable/4.0.x/django/contrib/auth/admin.py#L47-L63

Now, for example, to add a custom role field:

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin as BaseUserAdmin
from .models import User


class UserAdmin(BaseUserAdmin):
    fieldsets = BaseUserAdmin.fieldsets
    fieldsets[0][1]['fields'] = fieldsets[0][1]['fields'] + (
        'role',
    )


admin.site.register(User, UserAdmin)

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