Regression from APISelect option optimization

[hSaria]

Environment

• Python version: 3.6.8
• NetBox version: 2.6.10

Steps to Reproduce

1. Go to IP addresses page (/ipam/ip-addresses/)
2. Only the filter form, select a VRF

There are multiple places that this is happening at. This is one example.

Following #3812, it seems I messed up some APISelect-based fields and I'm still unsure what's affected and what's not (I'll put a comment with more info).

Expected Behavior

The list of VRFs is shown

Observed Behavior

Select is stuck at Searching...

[hSaria]

This seems to be related to the null option not being present, or rather no options being present at all.

Firstly, if you make the following change, the VRF field and most others start working:

--- a/netbox/utilities/templates/widgets/select_api.html
+++ b/netbox/utilities/templates/widgets/select_api.html
@@ -1,5 +1,5 @@
 <select name="{{ widget.name }}"{% include "django/forms/widgets/attrs.html" %}>{% for group_name, group_choices, group_index in widget.opt
-  <optgroup label="{{ group_name }}">{% endif %}{% for widget in group_choices %}{% if widget.attrs.selected %}
+  <optgroup label="{{ group_name }}">{% endif %}{% for widget in group_choices %}{% if widget.attrs.selected or widget.value == "null" %}
   {% include widget.template_name %}{% endif %}{% endfor %}{% if group_name %}
   </optgroup>{% endif %}{% endfor %}
 </select>

However, there is still at least one field that I found not working: the Rack group field in Racks (/dcim/racks/) and I have no idea why that one specifically is there.

I'm not 100% sure, but I think any static options (API will not return) will need to be put into the page (not filtered by the template). If it is just the null option that is always the exception, then the above diff will fix it, but if there instances where we mix multiple static options with an APISelect-based field, the patch won't work.

But again, the patch above still doesn't fix the Rack group field in Racks, and I can't figure out why.

[hSaria]

I think I found out why rack groups wasn't working: the default option has no value, so this fixes it

--- a/netbox/utilities/templates/widgets/select_api.html
+++ b/netbox/utilities/templates/widgets/select_api.html
@@ -1,5 +1,5 @@
 <select name="{{ widget.name }}"{% include "django/forms/widgets/attrs.html" %}>{% for group_name, group_choices, group_index in widget.optgroups %}{% if group_name %}
-  <optgroup label="{{ group_name }}">{% endif %}{% for widget in group_choices %}{% if widget.attrs.selected %}
+  <optgroup label="{{ group_name }}">{% endif %}{% for widget in group_choices %}{% if widget.attrs.selected or widget.value == "null" or not widget.value %}
   {% include widget.template_name %}{% endif %}{% endfor %}{% if group_name %}
   </optgroup>{% endif %}{% endfor %}
 </select>

I don't know if this is the best or most efficient solution considering I'm accounting for two exception manually

[hoalex]

This is also happening on the Devices page when trying to filter for a specific rack.

[jeremystretch]

Going to stick with option.value == "null" for now, until we have time to do some thorough cleanup around the select widgets. RackFilter.group_id (and possibly other fields) need to be changed to FilterChoiceField to populate null values correctly.

[hSaria]

@jeremystretch thanks for fixing and sorry for the mess.

[jeremystretch]

@hSaria No worries, I didn't catch it either.