Custom Fields Migration error 2.10.1

Environment

• Python version: 3.6.9
• NetBox version: migration from 2.9.4 to 2.10.1

Steps to Reproduce

1. have some custom fields in 2.9.4
2. ./upgrade.sh

Expected Behavior

Observed Behavior

Operations to perform:
  Apply all migrations: admin, auth, circuits, contenttypes, dcim, extras, ipam, secrets, sessions, taggit, tenancy, users, virtualization
Running migrations:
  Applying extras.0051_migrate_customfields...Traceback (most recent call last):
  File "netbox/manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/core/management/__init__.py", line 401, in execute_from_command_line
    utility.execute()
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/core/management/__init__.py", line 395, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/core/management/base.py", line 330, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/core/management/base.py", line 371, in execute
    output = self.handle(*args, **options)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/core/management/base.py", line 85, in wrapped
    res = handle_func(*args, **kwargs)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/core/management/commands/migrate.py", line 245, in handle
    fake_initial=fake_initial,
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/db/migrations/executor.py", line 117, in migrate
    state = self._migrate_all_forwards(state, plan, full_plan, fake=fake, fake_initial=fake_initial)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/db/migrations/executor.py", line 147, in _migrate_all_forwards
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/db/migrations/executor.py", line 227, in apply_migration
    state = migration.apply(state, schema_editor)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/db/migrations/migration.py", line 124, in apply
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state)
  File "/opt/netbox-2.10.1/venv/lib/python3.6/site-packages/django/db/migrations/operations/special.py", line 190, in database_forwards
    self.code(from_state.apps, schema_editor)
  File "/opt/netbox-2.10.1/netbox/extras/migrations/0051_migrate_customfields.py", line 69, in migrate_customfieldvalues
    cf_data['custom_field_data'][cfv.field.name] = deserialize_value(cfv.field, cfv.serialized_value)
TypeError: 'NoneType' object is not subscriptable

i insert some prints and cf_data is None from this DB Query: SELECT "dcim_rack"."custom_field_data" FROM "dcim_rack" INNER JOIN "dcim_site" ON ("dcim_rack"."site_id" = "dcim_site"."id") LEFT OUTER JOIN "dcim_rackgroup" ON ("dcim_rack"."group_id" = "dcim_rackgroup"."id") LEFT OUTER JOIN "dcim_site" T4 ON ("dcim_rackgroup"."site_id" = T4."id") WHERE "dcim_rack"."id" = 1 ORDER BY "dcim_site"."_name" ASC, T4."_name" ASC, "dcim_rackgroup"."name" ASC, "dcim_rack"."_name" ASC, "dcim_rack"."id" ASC

this field produce the error.

[rebortg]

Yes, this is a very old installation back to 2.2 or 2.3 maybe there some artifacts in the DB. i used your code snippet in the 0051_migrate_customfields.py file and the migration run without an error. At the moment i don’t see any issues with this custom field after the migration.

[csallen1204]

ImportError: cannot import name 'CustomFieldChoice' from 'extras.models'

@csallen1204 This is an unrelated issue pertaining to code that’s not part of the core NetBox project (startup_scripts/020_custom_fields.py). If you’re using the community Docker image, please raise a bug against that project.

Thanks @jeremystretch I found the script issue, fixed my version and reported it here https://github.com/netbox-community/netbox-docker/issues/373 in case anyone else lands here thinking it’s the same issue.