From dd707c97af7df048db7bb659fa11bc8002115804 Mon Sep 17 00:00:00 2001
From: Jeremy Stretch <stretch@packetlife.net>
Date: Mon, 17 Aug 2020 11:08:14 -0400
Subject: [PATCH] Cache custom fields on instance prior to save()

---
 netbox/extras/forms.py               | 15 +++++++++++++--
 netbox/extras/models/customfields.py |  1 -
 netbox/extras/signals.py             |  4 ----
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/netbox/extras/forms.py b/netbox/extras/forms.py
index cecbfae72..90ec828c7 100644
--- a/netbox/extras/forms.py
+++ b/netbox/extras/forms.py
@@ -29,6 +29,9 @@ class CustomFieldModelForm(forms.ModelForm):
 
         super().__init__(*args, **kwargs)
 
+        if self.instance._cf is None:
+            self.instance._cf = {}
+
         self._append_customfield_fields()
 
     def _append_customfield_fields(self):
@@ -48,9 +51,12 @@ class CustomFieldModelForm(forms.ModelForm):
             field_name = 'cf_{}'.format(cf.name)
             if self.instance.pk:
                 self.fields[field_name] = cf.to_form_field(set_initial=False)
-                self.fields[field_name].initial = self.custom_field_values.get(cf.name)
+                value = self.custom_field_values.get(cf.name)
+                self.fields[field_name].initial = value
+                self.instance._cf[cf.name] = value
             else:
                 self.fields[field_name] = cf.to_form_field()
+                self.instance._cf[cf.name] = self.fields[field_name].initial
 
             # Annotate the field in the list of CustomField form fields
             self.custom_fields.append(field_name)
@@ -77,13 +83,18 @@ class CustomFieldModelForm(forms.ModelForm):
             cfv.save()
 
     def save(self, commit=True):
+
+        # Cache custom field values on object prior to save to ensure change logging
+        for cf_name in self.custom_fields:
+            self.instance._cf[cf_name[3:]] = self.cleaned_data.get(cf_name)
+
         obj = super().save(commit)
 
         # Handle custom fields the same way we do M2M fields
         if commit:
             self._save_custom_fields()
         else:
-            self.save_custom_fields = self._save_custom_fields
+            obj.save_custom_fields = self._save_custom_fields
 
         return obj
 
diff --git a/netbox/extras/models/customfields.py b/netbox/extras/models/customfields.py
index 62e2ca4df..2671864fb 100644
--- a/netbox/extras/models/customfields.py
+++ b/netbox/extras/models/customfields.py
@@ -1,4 +1,3 @@
-import logging
 from collections import OrderedDict
 from datetime import date
 
diff --git a/netbox/extras/signals.py b/netbox/extras/signals.py
index 370f21e43..c5d1a7cf7 100644
--- a/netbox/extras/signals.py
+++ b/netbox/extras/signals.py
@@ -25,10 +25,6 @@ def _handle_changed_object(request, sender, instance, **kwargs):
     else:
         return
 
-    # Cache any custom field values to ensure they are captured during serialization
-    if hasattr(instance, 'cache_custom_fields'):
-        instance.cache_custom_fields()
-
     # Record an ObjectChange if applicable
     if hasattr(instance, 'to_objectchange'):
         objectchange = instance.to_objectchange(action)