Error in superuser creation NOT NULL constraint failed

Question

I have created a custom user model Student to modify the default signup page provided by Django.

from django.db import models
from django.contrib.auth.models import AbstractUser

class Student(AbstractUser):
    email = models.EmailField(unique=True)
    roll = models.CharField(max_length=200, blank=False)
    contact_no = models.DecimalField(
        max_digits=10, decimal_places=0, blank=False)

I then migrated the database by running:

python manage.py makemigrations students

python manage.py migrate

Now when I try to create a superuser using the command python manage.py createsuperuser, it shows the following error:

Traceback (most recent call last):
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/utils.py", line 85, in _execute
    return self.cursor.execute(sql, params)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/sqlite3/base.py", line 296, in execute
    return Database.Cursor.execute(self, query, params)
sqlite3.IntegrityError: NOT NULL constraint failed: students_student.contact_no

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 15, in <module>
    execute_from_command_line(sys.argv)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/core/management/base.py", line 316, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/contrib/auth/management/commands/createsuperuser.py", line 59, in execute
    return super().execute(*args, **options)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/core/management/base.py", line 353, in execute
    output = self.handle(*args, **options)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/contrib/auth/management/commands/createsuperuser.py", line 184, in handle
    self.UserModel._default_manager.db_manager(database).create_superuser(**user_data)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/contrib/auth/models.py", line 161, in create_superuser
    return self._create_user(username, email, password, **extra_fields)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/contrib/auth/models.py", line 144, in _create_user
    user.save(using=self._db)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/contrib/auth/base_user.py", line 73, in save
    super().save(*args, **kwargs)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/base.py", line 717, in save
    force_update=force_update, update_fields=update_fields)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/base.py", line 747, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/base.py", line 830, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/base.py", line 868, in _do_insert
    using=using, raw=raw)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/query.py", line 1133, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/models/sql/compiler.py", line 1285, in execute_sql
    cursor.execute(sql, params)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/utils.py", line 100, in execute
    return super().execute(sql, params)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/utils.py", line 68, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/utils.py", line 77, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/utils.py", line 85, in _execute
    return self.cursor.execute(sql, params)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/utils.py", line 85, in _execute
    return self.cursor.execute(sql, params)
  File "/home/anirudh/.local/share/virtualenvs/Amrita-event-manager-DHqKHtGE/lib/python3.5/site-packages/django/db/backends/sqlite3/base.py", line 296, in execute
    return Database.Cursor.execute(self, query, params)
django.db.utils.IntegrityError: NOT NULL constraint failed: students_student.contact_no

How do I create a superuser with these fields?

Answer 1

There are two possible way to do that. You can add roll and contact_no in require_fields so that superuser command will ask them or you can use custom usermanager to overwrite your create_superuser method.

Solution 1

Add roll and contact_no in REQUIRED_FIELDS

class Student(AbstractUser):
    email = models.EmailField(unique=True)
    roll = models.CharField(max_length=200, blank=False)
    contact_no = models.DecimalField(
        max_digits=10, decimal_places=0, blank=False)
    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['roll', 'contact_no',] # By doing so create superuser command will ask their input

Solution 2

Add custom usermanager and overwrite create_superuser method

from django.contrib.auth.models import BaseUserManager, AbstractUser
from django.db import models
from django.utils import timezone

class UserManager(BaseUserManager):
      def _create_user(self, email, password, **extra_fields):
            """Create and save a User with the given email and password."""
          if not email:
                raise ValueError('The email must be set')
          if not password:
                raise ValueError('The password must be set')
          email = self.normalize_email(email)
          user = self.model(email=email, **extra_fields)
          user.set_password(password)
          user.save(using=self._db)
          return user
      def create_superuser(self, email, password, **extra_fields):
        """Create and save a SuperUser with the given email and password."""
          extra_fields.setdefault('is_staff', True)
          extra_fields.setdefault('is_superuser', True)
          extra_fields.setdefault('roll', YOUR DESIRE VALUE )
          extra_fields.setdefault('contact_no', YOUR DESIRE VALUE)
          if extra_fields.get('is_staff') is not True:
              raise ValueError('Superuser must have is_staff=True.')
          if extra_fields.get('is_superuser') is not True:
              raise ValueError('Superuser must have is_superuser=True.')
          super_user = self._create_user(email, password, **extra_fields)
          return super_user

class Student(AbstractUser):
     email = models.EmailField(unique=True)
     roll = models.CharField(max_length=200, blank=False)
     contact_no = models.DecimalField(
       max_digits=10, decimal_places=0, blank=False)
     objects = UserManager()
     USERNAME_FIELD = 'email'