Closes #15621: User notifications (#16800)

* Initial work on #15621

* Signal receiver should ignore models which don't support notifications

* Flesh out NotificationGroup functionality

* Add NotificationGroup filters for users & groups

* Separate read & dimiss actions

* Enable one-click dismissals from notifications list

* Include total notification count in dropdown

* Drop 'kind' field from Notification model

* Register event types in the registry; add colors & icons

* Enable event rules to target notification groups

* Define dynamic choices for Notification.event_name

* Move event registration to core

* Add more job events

* Misc cleanup

* Misc cleanup

* Correct absolute URLs for notifications & subscriptions

* Optimize subscriber notifications

* Use core event types when queuing events

* Standardize queued event attribute to event_type; change content_type to object_type

* Rename Notification.event_name to event_type

* Restore NotificationGroupBulkEditView

* Add API tests

* Add view & filterset tests

* Add model documentation

* Fix tests

* Update notification bell when notifications have been cleared

* Ensure subscribe button appears only on relevant models

* Notifications/subscriptions cannot be ordered by object

* Misc cleanup

* Add event icon & type to notifications table

* Adjust icon sizing

* Mute color of read notifications

* Misc cleanup

netbox/extras/forms/bulk_import.py

@@ -3,16 +3,17 @@ import re
 from django import forms
 from django.contrib.postgres.forms import SimpleArrayField
 from django.core.exceptions import ObjectDoesNotExist
-from django.utils.safestring import mark_safe
 from django.utils.translation import gettext_lazy as _
 
 from core.models import ObjectType
 from extras.choices import *
 from extras.models import *
 from netbox.forms import NetBoxModelImportForm
+from users.models import Group, User
 from utilities.forms import CSVModelForm
 from utilities.forms.fields import (
-    CSVChoiceField, CSVContentTypeField, CSVModelChoiceField, CSVMultipleContentTypeField, SlugField,
+    CSVChoiceField, CSVContentTypeField, CSVModelChoiceField, CSVModelMultipleChoiceField, CSVMultipleContentTypeField,
+    SlugField,
 )
 
 __all__ = (
@@ -23,6 +24,7 @@ __all__ = (
     'EventRuleImportForm',
     'ExportTemplateImportForm',
     'JournalEntryImportForm',
+    'NotificationGroupImportForm',
     'SavedFilterImportForm',
     'TagImportForm',
     'WebhookImportForm',
@@ -247,3 +249,24 @@ class JournalEntryImportForm(NetBoxModelImportForm):
         fields = (
             'assigned_object_type', 'assigned_object_id', 'created_by', 'kind', 'comments', 'tags'
         )
+
+
+class NotificationGroupImportForm(CSVModelForm):
+    users = CSVModelMultipleChoiceField(
+        label=_('Users'),
+        queryset=User.objects.all(),
+        required=False,
+        to_field_name='username',
+        help_text=_('User names separated by commas, encased with double quotes')
+    )
+    groups = CSVModelMultipleChoiceField(
+        label=_('Groups'),
+        queryset=Group.objects.all(),
+        required=False,
+        to_field_name='name',
+        help_text=_('Group names separated by commas, encased with double quotes')
+    )
+
+    class Meta:
+        model = NotificationGroup
+        fields = ('name', 'description', 'users', 'groups')