nautobot.extras.plugins.api.views.PluginsAPIRootView creates null entries when PluginConfig does not define a base_url

[lampwins]

Environment

• Python version: 3.9
• Nautobot version: 1.0.0b3

Steps to Reproduce

1. Create a plugin with name set to myplugin but in its PluginConfig do not define a base_url
2. Create a model and standard API viewset in the plugin
3. Navigate to the /api/plugins/ endpoint

Expected Behavior

The response should contain the hyperlink to the plugin's root view with the key myplugin

Observed Behavior

The plugin's hyperlink key is null.

This is caused because nautobot.extras.plugins.PluginConfig defines base_url = None and nautobot.extras.plugins.api.views.PluginsAPIRootView incorrectly checks if base_url has been define in the plugin's config. See

nautobot/nautobot/extras/plugins/__init__.py

Line 41 in ac1768a

base_url = None

and

nautobot/nautobot/extras/plugins/views.py

Line 72 in ac1768a

getattr(app_config, "base_url", app_config.label),

The base_url attribute is actually defined but it is None so label is never actually considered. We just need to adjust this logic.

[FragmentedPacket]

I'm curious after looking into this. Do we need to check/validate what settings should NOT be left as None?

It appears we aren't doing any validations for required attributes for PluginConfig, but just for the plugin's actual settings.