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Python Django Authentication Users and Authorization Custom User Model

Posted by Ben Ella
Ben Ella
17,872 Points

I get an error when I try to makemigrations and migrate

error:

django.db.migrations.exceptions.InconsistentMigrationHistory: Migration admin.0001_initial is applied before its dependency accounts.0001_initial on database 'default'.

My User model:

class User(AbstractBaseUser, PermissionsMixin):

    email = models.EmailField(unique=True)
    username = models.CharField(max_length=40, unique=True)
    display_name = models.CharField(max_length=140)
    avatar = models.ImageField(blank=True, null=True)
    date_joined = models.DateTimeField(default=timezone.now)
    is_active = models.BooleanField(default=True)
    is_staff = models.BooleanField(default=False)

    objects = UserManager()

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

    def __str__(self):
        return self.display_name


    def get_short_name(self):
        return self.display_name

    def get_full_name(self):
        return "{} ({})".format(self.display_name, self.email)

    def get_long_name(self):
        return "{} ({})".format(self.display_name, self.email)
Fernando Cordeiro
Fernando Cordeiro
34,597 Points

One year too late, but here's how I solved it:

  1. went through all the migration folders and deleted everything (pycache, migration files) but the __init__.pys.
  2. deleted db.sqlite3 from the root too 3 finally, ran in the terminal python manage.py makemigrations and python manage.py migrate

Kenneth Love, is there any other, less drastic way?

1 Answer

Jonatan Witoszek
Jonatan Witoszek
15,384 Points
Jonatan Witoszek
Jonatan Witoszek
15,384 Points

In my case though deleting all other migrations (that step might have been unnesesary), removing django.contrib.admin and path('admin/', admin.site.urls), in msg/urls.py, then running migrations resolved the problem. You can add these again later to bring the admin back.

It is much bigger though:

This issue is described in Django Documentation

Quoting it:

Changing AUTH_USER_MODEL after you’ve created database tables is significantly more difficult since it affects foreign keys and many-to-many relationships, for example. Due to limitations of Django’s dynamic dependency feature for swappable models, the model referenced by AUTH_USER_MODEL must be created in the first migration of its app (usually called 0001_initial); otherwise, you’ll have dependency issues.

In older version they've even stated:

Changing this setting after you have tables created is not supported by makemigrations and will result in you having to manually fix your schema, port your data from the old user table, and possibly manually reapply some migrations.

While researching this issue I've also found this great answer on StackOverflow.

You have to be extra-careful when doing this sort of things. As shown in the video, I have deleted all users this way and the new user I have created mapped all Kenneth posts to that user ¯_(ツ)_/¯

Fernando Cordeiro