Config Context error in Virtual Machine and Device

[maximebrun]

Environment

• Python version: 3.7.9 (from docker image python:3.7-alpine)
• NetBox version: 2.9.8 (migrate from 2.6.9)

Steps to Reproduce

1. Create a VM.
2. Add 2 tags to the VM previously created.
3. Go to Config Context tab of this VM.

Expected Behavior

Display config context information.

Observed Behavior

An Error message :

MultipleObjectsReturned at /virtualization/virtual-machines/399/config-context/

get() returned more than one VirtualMachine -- it returned 2!

2 is the number of tag attached to the VM. A vm with 4 tags will return a error message "-- it returned 4!".

Comment

Problem exist with virtual machine and device.

I'm not very confident it is the way to really fix the issue but perhaps it can help :

Problem seems to be in ConfigContextModelQuerySet class. Adding a distinct in queryset of class VirtualMachineConfigContextView fix the error (I don't use config context so i can't test more).

 class VirtualMachineConfigContextView(ObjectConfigContextView):
-    queryset = VirtualMachine.objects.annotate_config_context_data()
+    queryset = VirtualMachine.objects.distinct().annotate_config_context_data()
     base_template = 'virtualization/virtualmachine.html'

[krombel]

We are running on v2.9.9 now but still have the issue:

<class 'virtualization.models.VirtualMachine.MultipleObjectsReturned'>

get() returned more than one VirtualMachine -- it returned 2!

Python version: 3.8.6
NetBox version: 2.9.9

This is the stack trace:

netbox_1         | Internal Server Error: /virtualization/virtual-machines/11/config-context/
netbox_1         | Traceback (most recent call last):
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
netbox_1         |     response = get_response(request)
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/django/core/handlers/base.py", line 179, in _get_response
netbox_1         |     response = wrapped_callback(request, *callback_args, **callback_kwargs)
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/django/views/generic/base.py", line 73, in view
netbox_1         |     return self.dispatch(request, *args, **kwargs)
netbox_1         |   File "/opt/netbox/netbox/utilities/views.py", line 124, in dispatch
netbox_1         |     return super().dispatch(request, *args, **kwargs)
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/django/views/generic/base.py", line 101, in dispatch
netbox_1         |     return handler(request, *args, **kwargs)
netbox_1         |   File "/opt/netbox/netbox/extras/views.py", line 146, in get
netbox_1         |     obj = get_object_or_404(self.queryset, pk=pk)
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/django/shortcuts.py", line 76, in get_object_or_404
netbox_1         |     return queryset.get(*args, **kwargs)
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/cacheops/query.py", line 353, in get
netbox_1         |     return qs._no_monkey.get(qs, *args, **kwargs)
netbox_1         |   File "/usr/local/lib/python3.8/site-packages/django/db/models/query.py", line 433, in get
netbox_1         |     raise self.model.MultipleObjectsReturned(
netbox_1         | virtualization.models.VirtualMachine.MultipleObjectsReturned: get() returned more than one VirtualMachine -- it returned 2!
netbox_1         | 192.168.0.2 - - [10/Nov/2020:13:58:48 +0000] "GET /virtualization/virtual-machines/11/config-context/ HTTP/1.0" 500 1854 "https://nb.ov.ffmuc.net/virtualization/virtual-machines/11/" "Mozilla/5.0"

If it makes any difference: We are running netbox in docker. We use the tags to add or remove config context based on tags.
In case we remove one tag we can see the config context again in the UI. The API does not suffer of this issue so this is only an UI issue

[colawebrunner]

We are also now running on v2.9.9, but still having the issue:

<class 'virtualization.models.VirtualMachine.MultipleObjectsReturned'>

get() returned more than one VirtualMachine -- it returned 2!

Python version: 3.7.9
NetBox version: 2.9.9

This is the traceback:

Traceback (most recent call last):
  File "/opt/netbox/venv/lib/python3.7/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/opt/netbox/venv/lib/python3.7/site-packages/django/core/handlers/base.py", line 179, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/opt/netbox/venv/lib/python3.7/site-packages/django/views/generic/base.py", line 73, in view
    return self.dispatch(request, *args, **kwargs)
  File "/opt/netbox/netbox/utilities/views.py", line 124, in dispatch
    return super().dispatch(request, *args, **kwargs)
  File "/opt/netbox/venv/lib/python3.7/site-packages/django/views/generic/base.py", line 101, in dispatch
    return handler(request, *args, **kwargs)
  File "/opt/netbox/netbox/extras/views.py", line 146, in get
    obj = get_object_or_404(self.queryset, pk=pk)
  File "/opt/netbox/venv/lib/python3.7/site-packages/django/shortcuts.py", line 76, in get_object_or_404
    return queryset.get(*args, **kwargs)
  File "/opt/netbox/venv/lib/python3.7/site-packages/cacheops/query.py", line 353, in get
    return qs._no_monkey.get(qs, *args, **kwargs)
  File "/opt/netbox/venv/lib/python3.7/site-packages/django/db/models/query.py", line 436, in get
    num if not limit or num < limit else 'more than %s' % (limit - 1),

Exception Type: MultipleObjectsReturned at /virtualization/virtual-machines/1974/config-context/
Exception Value: get() returned more than one VirtualMachine -- it returned 2!