From f53810ebb29f0ef26c53b5be1973263e89b01f54 Mon Sep 17 00:00:00 2001
From: Jeremy Stretch <stretch@packetlife.net>
Date: Fri, 9 Oct 2020 15:53:45 -0400
Subject: [PATCH] Fixes #5231: Fix KeyError exception when viewing object with
 custom link and debugging is disabled

---
 docs/release-notes/version-2.9.md          |  8 +++++++
 netbox/extras/templatetags/custom_links.py |  2 +-
 netbox/extras/tests/test_views.py          | 25 +++++++++++++++++++++-
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/docs/release-notes/version-2.9.md b/docs/release-notes/version-2.9.md
index 3a284a121..2795e311a 100644
--- a/docs/release-notes/version-2.9.md
+++ b/docs/release-notes/version-2.9.md
@@ -1,5 +1,13 @@
 # NetBox v2.9
 
+## v2.9.7 (FUTURE)
+
+### Bug Fixes
+
+* [#5231](https://github.com/netbox-community/netbox/issues/5231) - Fix KeyError exception when viewing object with custom link and debugging is disabled
+
+---
+
 ## v2.9.6 (2020-10-09)
 
 ### Bug Fixes
diff --git a/netbox/extras/templatetags/custom_links.py b/netbox/extras/templatetags/custom_links.py
index 84c274f6f..9fbec489d 100644
--- a/netbox/extras/templatetags/custom_links.py
+++ b/netbox/extras/templatetags/custom_links.py
@@ -33,7 +33,7 @@ def custom_links(context, obj):
     # Pass select context data when rendering the CustomLink
     link_context = {
         'obj': obj,
-        'debug': context['debug'],  # django.template.context_processors.debug
+        'debug': context.get('debug', False),  # django.template.context_processors.debug
         'request': context['request'],  # django.template.context_processors.request
         'user': context['user'],  # django.contrib.auth.context_processors.auth
         'perms': context['perms'],  # django.contrib.auth.context_processors.auth
diff --git a/netbox/extras/tests/test_views.py b/netbox/extras/tests/test_views.py
index 4ff0b59c8..45a246f38 100644
--- a/netbox/extras/tests/test_views.py
+++ b/netbox/extras/tests/test_views.py
@@ -2,11 +2,13 @@ import urllib.parse
 import uuid
 
 from django.contrib.auth.models import User
+from django.contrib.contenttypes.models import ContentType
+from django.test import override_settings
 from django.urls import reverse
 
 from dcim.models import Site
 from extras.choices import ObjectChangeActionChoices
-from extras.models import ConfigContext, ObjectChange, Tag
+from extras.models import ConfigContext, CustomLink, ObjectChange, Tag
 from utilities.testing import ViewTestCases, TestCase
 
 
@@ -124,3 +126,24 @@ class ObjectChangeTestCase(TestCase):
         objectchange = ObjectChange.objects.first()
         response = self.client.get(objectchange.get_absolute_url())
         self.assertHttpStatus(response, 200)
+
+
+class CustomLinkTest(TestCase):
+    user_permissions = ['dcim.view_site']
+
+    def test_view_object_with_custom_link(self):
+        customlink = CustomLink(
+            content_type=ContentType.objects.get_for_model(Site),
+            name='Test',
+            text='FOO {{ obj.name }} BAR',
+            url='http://example.com/?site={{ obj.slug }}',
+            new_window=False
+        )
+        customlink.save()
+
+        site = Site(name='Test Site', slug='test-site')
+        site.save()
+
+        response = self.client.get(site.get_absolute_url(), follow=True)
+        self.assertEqual(response.status_code, 200)
+        self.assertIn(f'FOO {site.name} BAR', str(response.content))