refactor: settings are read through django.conf

instances/forms.py and instances/models.py imported values from the
webvirtcloud.settings module itself, which bypasses DJANGO_SETTINGS_MODULE
(settings-dev, test overrides) and runs the module a second time. They
now read django.conf.settings. webvirtcloud/urls.py also loses its
fallback that set REST_FRAMEWORK's schema class at import for settings.py
copies without it: the template sets it, and an older settings.py is
rebuilt from the template when updating.

instances/forms.py

@@ -3,7 +3,6 @@ import re
 from django import forms
 from django.conf import settings
 from django.utils.translation import gettext_lazy as _
-from webvirtcloud.settings import QEMU_CONSOLE_LISTENER_ADDRESSES, QEMU_KEYMAPS
 
 from .models import CreateInstance, Flavor
 from .utils import nic_macs
@@ -62,11 +61,11 @@ class ConsoleForm(forms.Form):
         if "pty" in (instance.config_console_type, self.data.get("console_type")):
             del self.fields["password_action"], self.fields["password"]
             return
-        keymap_choices = [("auto", _("Auto"))] + list((c, c) for c in QEMU_KEYMAPS)
+        keymap_choices = [("auto", _("Auto"))] + list((c, c) for c in settings.QEMU_KEYMAPS)
         # Only administrators choose the listen address: beyond localhost the
         # console is reachable from the network. A disabled field ignores
         # posted values.
-        listeners = list(QEMU_CONSOLE_LISTENER_ADDRESSES)
+        listeners = list(settings.QEMU_CONSOLE_LISTENER_ADDRESSES)
         # an address set elsewhere (the XML editor) is offered, so a save keeps it
         if listener and listener not in dict(listeners):
             listeners.append((listener, listener))

instances/models.py

@@ -1,4 +1,5 @@
 from computes.models import Compute
+from django.conf import settings
 from django.core.validators import MinValueValidator
 from django.db import models
 from django.utils.functional import cached_property
@@ -11,7 +12,6 @@ from libvirt import (
 from operations import claims
 from operations.models import Claim
 from vrtManager.instance import PERSISTENT_XML, wvmInstance
-from webvirtcloud.settings import QEMU_CONSOLE_LISTENER_ADDRESSES
 
 
 class Flavor(models.Model):
@@ -466,7 +466,7 @@ class CreateInstance(models.Model):
         max_length=16, error_messages={"required": _("Please select a video driver")}
     )
     listener_addr = models.CharField(
-        max_length=20, choices=QEMU_CONSOLE_LISTENER_ADDRESSES
+        max_length=20, choices=settings.QEMU_CONSOLE_LISTENER_ADDRESSES
     )
 
     class Meta:

webvirtcloud/urls.py

@@ -9,17 +9,6 @@ from appsettings.views import appsettings
 from console.views import console
 from instances.views import index
 
-# Fallback for existing installations where REST_FRAMEWORK.DEFAULT_SCHEMA_CLASS is not configured in settings.py
-user_rf = getattr(settings, "REST_FRAMEWORK", None)
-if not user_rf or "DEFAULT_SCHEMA_CLASS" not in user_rf:
-    try:
-        from rest_framework.settings import api_settings
-        from drf_spectacular.openapi import AutoSchema
-
-        api_settings.DEFAULT_SCHEMA_CLASS = AutoSchema
-    except (ImportError, AttributeError):
-        pass
-
 urlpatterns = [
     path("", index, name="index"),
     path("admin/", include(("admin.urls", "admin"), namespace="admin")),