Fixes netbox-community#7279: Fix exception when tracing cable with no associated path

Author: jeremystretch

docs/release-notes/version-3.0.md

@@ -15,6 +15,7 @@
 * [#7167](https://github.com/netbox-community/netbox/issues/7167) - Ensure consistent font size when using monospace formatting
 * [#7226](https://github.com/netbox-community/netbox/issues/7226) - Exempt GraphQL API requests from CSRF inspection
 * [#7248](https://github.com/netbox-community/netbox/issues/7248) - Fix global search results section links
+* [#7279](https://github.com/netbox-community/netbox/issues/7279) - Fix exception when tracing cable with no associated path
 
 ---
 

netbox/dcim/views.py

@@ -2411,6 +2411,12 @@ def get_extra_context(self, request, instance):
             else:
                 path = related_paths.first()
 
+        # No paths found
+        if path is None:
+            return {
+                'path': None
+            }
+
         # Get the total length of the cable and whether the length is definitive (fully defined)
         total_length, is_definitive = path.get_total_length() if path else (None, False)
 

netbox/templates/dcim/cable_trace.html

@@ -5,7 +5,10 @@
 
 {% block content %}
     <div class="row">
+
+        {# Cable trace SVG & options #}
         <div class="col col-md-5">
+          {% if path %}
             <div class="text-center my-3">
                 <object data="{{ svg_url }}" class="rack_elevation"></object>
                 <a class="btn btn-outline-primary btn-sm my-3" href="{{ svg_url }}">
@@ -51,9 +54,15 @@ <h3 class="text-center text-success">Trace Completed</h3>
                     {% endif %}
                 {% endwith %}
             </div>
+          {% else %}
+            <h3 class="text-center text-muted my-3">
+              No paths found
+            </h3>
+          {% endif %}
         </div>
-        <div class="col col-md-7">
 
+        {# Related paths #}
+        <div class="col col-md-7">
             <div class="card">
                 <h5 class="card-header">
                   Related Paths
@@ -95,7 +104,7 @@ <h5 class="card-header">
                     </table>
                 </div>
             </div>
-
         </div>
+
     </div>
 {% endblock %}