Introduce ObjectAttribute for displaying read-only instance attributes on forms

netbox/utilities/forms/rendering.py

@@ -3,8 +3,8 @@ import string
 from functools import cached_property
 
 __all__ = (
-    'FieldGroup',
     'InlineFields',
+    'ObjectAttribute',
     'TabbedFieldGroups',
 )
 
@@ -41,3 +41,9 @@ class TabbedFieldGroups:
                 'fields': group.field_names,
             } for i, group in enumerate(self.groups, start=1)
         ]
+
+
+class ObjectAttribute:
+
+    def __init__(self, name):
+        self.name = name

netbox/utilities/templates/form_helpers/render_fieldset.html

@@ -12,6 +12,17 @@
       {# Single form field #}
       {% render_field items.0 %}
 
+    {% elif layout == 'attribute' %}
+      {# A static attribute of the form's instance #}
+      <div class="row mb-3">
+        <label class="col-sm-3 col-form-label text-lg-end required">{{ title }}</label>
+        <div class="col">
+          <div class="form-control-plaintext">
+            {{ items.0|linkify }}
+          </div>
+        </div>
+      </div>
+
     {% elif layout == 'inline' %}
       {# Multiple form fields on the same line #}
       <div class="row mb-3">

netbox/utilities/templatetags/form_helpers.py

@@ -1,6 +1,6 @@
 from django import template
 
-from utilities.forms.rendering import InlineFields, TabbedFieldGroups
+from utilities.forms.rendering import InlineFields, ObjectAttribute, TabbedFieldGroups
 
 __all__ = (
     'getfield',
@@ -81,6 +81,13 @@ def render_fieldset(form, fieldset, heading=None):
                 ('tabs', None, tabs)
             )
 
+        elif type(item) is ObjectAttribute:
+            value = getattr(form.instance, item.name)
+            label = value._meta.verbose_name if hasattr(value, '_meta') else item.name
+            rows.append(
+                ('attribute', label.title(), [value])
+            )
+
         # A single form field
         elif item in form.fields:
             rows.append(