Internal server error on list Job Template/Jobs when source workflow deleted

[MrFoxTrot]

Please confirm the following

• I agree to follow this project's code of conduct.
• I have checked the current issues for duplicates.
• I understand that AWX is open source software provided for free and that I might not receive a timely response.
• I am NOT reporting a (potential) security vulnerability. (These should be emailed to security@ansible.com instead.)

Bug Summary

Accessing a Job (from JobTemplate) via UI/API after deleting its parent-parent workflow results in a 500 Internal Server Error.

AWX version

24.4.0

Select the relevant components

• UI
• UI (tech preview)
• API
• Docs
• Collection
• CLI
• Other

Installation method

kubernetes

Modifications

no

Ansible version

No response

Operating system

No response

Web browser

No response

Steps to reproduce

Setup:

• wf1 - Workflow with one node (wf2)
• wf2 - Workflow with one node (jt1)
• jt1 - JobTemplate (with random task)

1. Start wf1
2. Wait for its complition
3. Delete wf1 job
4. Open jt1 job with UI/API
5. Got 500 - Internal server error

Expected results

Opened job with "-" in source_worflow

Actual results

500 - Internal server error

Additional information

django.request Internal Server Error: /api/v2/job_templates/1268/jobs/
Traceback (most recent call last):
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/django/core/handlers/exception.py", line 55, in inner
    response = get_response(request)
               ^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/django/core/handlers/base.py", line 197, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib64/python3.11/contextlib.py", line 81, in inner
    return func(*args, **kwds)
           ^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/django/views/decorators/csrf.py", line 56, in wrapper_view
    return view_func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/django/views/generic/base.py", line 104, in view
    return self.dispatch(request, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/generics.py", line 342, in dispatch
    return super(APIView, self).dispatch(request, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/views.py", line 509, in dispatch
    response = self.handle_exception(exc)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/views.py", line 469, in handle_exception
    self.raise_uncaught_exception(exc)
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/views.py", line 480, in raise_uncaught_exception
    raise exc
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/views.py", line 506, in dispatch
    response = handler(request, *args, **kwargs)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/generics.py", line 203, in get
    return self.list(request, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/mixins.py", line 43, in list
    return self.get_paginated_response(serializer.data)
                                       ^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/serializers.py", line 795, in data
    ret = super().data
          ^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/serializers.py", line 249, in data
    self._data = self.to_representation(self.instance)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/serializers.py", line 713, in to_representation
    return [
           ^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/serializers.py", line 714, in <listcomp>
    self.child.to_representation(item) for item in iterable
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 3535, in to_representation
    ret = super(JobSerializer, self).to_representation(obj)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 943, in to_representation
    ret = super(UnifiedJobListSerializer, self).to_representation(obj)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 885, in to_representation
    ret = super(UnifiedJobSerializer, self).to_representation(obj)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 3276, in to_representation
    ret = super(JobOptionsSerializer, self).to_representation(obj)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/serializers.py", line 538, in to_representation
    ret[field.field_name] = field.to_representation(attribute)
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/rest_framework/fields.py", line 1872, in to_representation
    return method(value)
           ^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 428, in _get_summary_fields
    return {} if obj is None else self.get_summary_fields(obj)
                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 3545, in get_summary_fields
    summary_fields = super(JobSerializer, self).get_summary_fields(obj)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/api/serializers.py", line 844, in get_summary_fields
    ancestor = obj.ancestor_job
               ^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/main/models/unified_jobs.py", line 1640, in ancestor_job
    return self.get_workflow_job().ancestor_job if self.spawned_by_workflow else self
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/var/lib/awx/venv/awx/lib64/python3.11/site-packages/awx/main/models/unified_jobs.py", line 1640, in ancestor_job
    return self.get_workflow_job().ancestor_job if self.spawned_by_workflow else self
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'ancestor_job'

[thedoubl3j]

@MrFoxTrot Thanks for opening this issue, I do have one questions around the expected results, just to make sure I am understanding. After the workflow has been deleted, you are expecting that if you navigate to the job_template that was assigned to the node in that workflow, that it should open/shown? (aka like launch or edit etc). I would expect that to be the case. I will see if I can get time to see if I can reproduce this on devel, just wanted to make sure I got the steps correct.