nautobot-server loaddata errors for ObjectChange records

[mzbroch]

Environment

• Nautobot version (Docker tag too if applicable): 34c06ba7a177 (v2.0.0b1)
• Python version: 3.8
• Database platform, version:
• Middleware(s):

Steps to Reproduce

1. dumpdata as per Nautobot documentation (https://docs.nautobot.com/projects/core/en/v2.0.0-beta.1/administration/nautobot-server/?h=dumpdata#dumpdata)
2. loaddata as per Nautobot documentation

Expected Behavior

loaddata works

Observed Behavior

loaddata errors :

root@34c06ba7a177:/source# nautobot-server dumpdata --natural-foreign --natural-primary --exclude contenttypes --exclude auth.permission --format json --indent 2 --traceback  > /tmp/nautobot_dump.json
08:17:03.254 DEBUG   nautobot.core.celery __init__.py        import_jobs_as_celery_tasks() :
  Importing system Jobs
08:17:03.449 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositorySync
08:17:03.455 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositoryDryRun
08:17:04.736 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleDryRunJob
08:17:04.737 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleJob
08:17:04.737 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleHiddenJob
08:17:04.738 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleLoggingJob
08:17:04.738 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleJobHookReceiver
08:17:04.739 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleSimpleJobButtonReceiver
08:17:04.740 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleComplexJobButtonReceiver

root@34c06ba7a177:/source# nautobot-server loaddata --traceback /tmp/nautobot_dump.json
08:17:26.171 DEBUG   nautobot.core.celery __init__.py        import_jobs_as_celery_tasks() :
  Importing system Jobs
08:17:26.378 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositorySync
08:17:26.385 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job nautobot.core.jobs.GitRepositoryDryRun
08:17:28.808 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleDryRunJob
08:17:28.809 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleJob
08:17:28.809 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleHiddenJob
08:17:28.810 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleLoggingJob
08:17:28.810 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleJobHookReceiver
08:17:28.811 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleSimpleJobButtonReceiver
08:17:28.812 DEBUG   nautobot.core.celery __init__.py                      register_jobs() :
  Registering job example_plugin.jobs.ExampleComplexJobButtonReceiver
Traceback (most recent call last):
  File "/usr/local/lib/python3.8/site-packages/django/core/serializers/json.py", line 70, in Deserializer
    yield from PythonDeserializer(objects, **options)
  File "/usr/local/lib/python3.8/site-packages/django/core/serializers/python.py", line 148, in Deserializer
    obj = base.build_instance(Model, data, using)
  File "/usr/local/lib/python3.8/site-packages/django/core/serializers/base.py", line 263, in build_instance
    natural_key = Model(**data).natural_key()
  File "/source/nautobot/core/models/__init__.py", line 90, in natural_key
    for lookups in [lookup.split("__") for lookup in self.natural_key_field_lookups]:
  File "/usr/local/lib/python3.8/site-packages/django/utils/functional.py", line 61, in __get__
    return self.fget(cls)
  File "/source/nautobot/core/models/__init__.py", line 146, in natural_key_field_lookups
    raise AttributeError(
AttributeError: Unable to identify an intrinsic natural-key definition for ObjectChange. If there isn't at least one UniqueConstraint, unique_together, or field with unique=True, you probably need to explicitly declare the 'natural_key_field_names' for this model, or potentially override the default 'natural_key_field_lookups' implementation for this model.

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

Traceback (most recent call last):
  File "/usr/local/bin/nautobot-server", line 6, in <module>
    sys.exit(main())
  File "/source/nautobot/core/cli/__init__.py", line 54, in main
    run_app(
  File "/source/nautobot/core/runner/runner.py", line 263, in run_app
    management.execute_from_command_line([runner_name, command] + command_args)
  File "/usr/local/lib/python3.8/site-packages/django/core/management/__init__.py", line 419, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python3.8/site-packages/django/core/management/__init__.py", line 413, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python3.8/site-packages/django/core/management/base.py", line 354, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/usr/local/lib/python3.8/site-packages/django/core/management/base.py", line 398, in execute
    output = self.handle(*args, **options)
  File "/usr/local/lib/python3.8/site-packages/django/core/management/commands/loaddata.py", line 78, in handle
    self.loaddata(fixture_labels)
  File "/usr/local/lib/python3.8/site-packages/django/core/management/commands/loaddata.py", line 123, in loaddata
    self.load_label(fixture_label)
  File "/usr/local/lib/python3.8/site-packages/django/core/management/commands/loaddata.py", line 181, in load_label
    for obj in objects:
  File "/usr/local/lib/python3.8/site-packages/django/core/serializers/json.py", line 74, in Deserializer
    raise DeserializationError() from exc
django.core.serializers.base.DeserializationError: Problem installing fixture '/tmp/nautobot_dump.json':

[bryanculver]

Are you dumping and loading between different Nautobot versions?

[glennmatthews]

Looks like a miss in #1574, as ObjectChange isn't mentioned in #2907/#2908/#2909. More fuel for us needing to do #3752 though.

[mzbroch]

Are you dumping and loading between different Nautobot versions?

Both on same container instance from 34c06ba7a177 (v2.0.0b1)

[itdependsnetworks]

If there is such a thing as priority on beta code, this would be one I would vote for. We are using similar constructs for our data generation processes and it is not working, which means it is more difficult to test, and given the amount of changes that is obviously problematic.

[glennmatthews]

It's also worth being aware of #3666 in that case, which may take some time longer to resolve than this specific issue.

[glennmatthews]

Resolved by #3896.