django.db.migrations.exceptions.NodeNotFoundError：迁移accounts.0001_initial依赖项引用不存在的父节点

Question

I'm trying to deploy my project on heroku,i'm using django 3.1 and i'm unable to do that. I'm getting error due to migrations. Please i humble request you to give some time to this question to resolve this problem. Whenever i run the command heroku run python manage.py migrate ,it gives following traceback.

Traceback (most recent call last):
  File "manage.py", line 22, in <module>
    main()
  File "manage.py", line 18, in main
    execute_from_command_line(sys.argv)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/base.py", line 371, in execute
    output = self.handle(*args, **options)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/base.py", line 85, in wrapped
    res = handle_func(*args, **kwargs)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/core/management/commands/migrate.py", line 92, in handle
    executor = MigrationExecutor(connection, self.migration_progress_callback)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/db/migrations/executor.py", line 18, in __init__
    self.loader = MigrationLoader(self.connection)
  File "/app/.heroku/python/lib/python3.6/site-packages/django/db/migrations/loader.py", line 53, in __init__
    self.build_graph()
  File "/app/.heroku/python/lib/python3.6/site-packages/django/db/migrations/loader.py", line 255, in build_graph
    self.graph.validate_consistency()
  File "/app/.heroku/python/lib/python3.6/site-packages/django/db/migrations/graph.py", line 195, in validate_consistency
    [n.raise_error() for n in self.node_map.values() if isinstance(n, DummyNode)]
  File "/app/.heroku/python/lib/python3.6/site-packages/django/db/migrations/graph.py", line 195, in <listcomp>
    [n.raise_error() for n in self.node_map.values() if isinstance(n, DummyNode)]
  File "/app/.heroku/python/lib/python3.6/site-packages/django/db/migrations/graph.py", line 58, in raise_error
    raise NodeNotFoundError(self.error_message, self.key, origin=self.origin)
django.db.migrations.exceptions.NodeNotFoundError: Migration accounts.0001_initial dependencies reference nonexistent parent node ('auth', '0023_remove_user_current_balance')

migration dependency

 dependencies = [
        ('auth', '0023_remove_user_current_balance'),
    ]

account.model

GENDER_CHOICES = (
    ('male','Male'),
    ('female','Female'),
    )
class User(auth.models.AbstractUser):
    
    current_balance = models.IntegerField(("user balance"),default=0, blank=True, null=True)
    age = models.IntegerField(("age"),blank=True, null=True)
    gender = models.CharField(("gender"), max_length=50,choices=GENDER_CHOICES,null=True)
    nationality = models.CharField(("nationality"), max_length=50,null=True)

    def __str__(self):
        return "@{}".format(self.username)

When i tried to comment out the dependency, Then it returned me: raise ValueError('Related model %r cannot be resolved' % self.remote_field.model)ValueError: Related model 'auth.Group' cannot be resolved

if more code is require then tell me in a comment section thank you.

Answer 1

I had the same problem. It is because of the inconsistent migration history. So I deleted the migrations directory in all installed apps and then called python manage.py makemigrations command. The new migrations had no problem.

Answer 2

This may happen if you remove some of past migration. All migrations create a graph (tree like structure). You just have to make sure there is no hanging branches in it that lead to previous branch that is not part of the tree anymore. You may put it on the paper to visualise it.

Fix would be:

1. To remove dependency from the list in case of branch :

Let's say affiliate app is deleted (with its migrations)

dependencies = [
    ('affiliate', '0003_remove_affiliateaccount_project'),
    ('partner', '0073_auto_20191008_1705'),
]

solution:

dependencies = [
    ('partner', '0073_auto_20191008_1705'),
]

2. To point it on different endpoint

   dependencies = [ ('auth', '0023_remove_user_current_balance'), ]

solution:

dependencies = [
    ('partner', 'XXXX_head_that_exists_YYYYMMDD_XXXX'),
]