Improved logic for recording cable path connection status

netbox/circuits/models.py

@@ -237,7 +237,7 @@ class CircuitTermination(CableTermination):
     )
     connection_status = models.NullBooleanField(
         choices=CONNECTION_STATUS_CHOICES,
-        default=CONNECTION_STATUS_CONNECTED
+        blank=True
     )
     port_speed = models.PositiveIntegerField(
         verbose_name='Port speed (Kbps)'

netbox/dcim/models.py

@@ -88,7 +88,7 @@ class CableTermination(models.Model):
     class Meta:
         abstract = True
 
-    def trace(self, position=1):
+    def trace(self, position=1, follow_circuits=False):
         """
         Return a list representing a complete cable path, with each individual segment represented as a three-tuple:
             [
@@ -97,7 +97,7 @@ class CableTermination(models.Model):
                 (termination E, cable, termination F)
             ]
         """
-        def get_peer_port(termination, position=1):
+        def get_peer_port(termination, position=1, follow_circuits=False):
             from circuits.models import CircuitTermination
 
             # Map a front port to its corresponding rear port
@@ -117,7 +117,7 @@ class CableTermination(models.Model):
                 return peer_port, 1
 
             # Follow a circuit to its other termination
-            elif isinstance(termination, CircuitTermination):
+            elif isinstance(termination, CircuitTermination) and follow_circuits:
                 peer_termination = termination.get_peer_termination()
                 if peer_termination is None:
                     return None, None
@@ -133,7 +133,7 @@ class CableTermination(models.Model):
         far_end = self.cable.termination_b if self.cable.termination_a == self else self.cable.termination_a
         path = [(self, self.cable, far_end)]
 
-        peer_port, position = get_peer_port(far_end, position)
+        peer_port, position = get_peer_port(far_end, position, follow_circuits)
         if peer_port is None:
             return path
 
@@ -1704,7 +1704,7 @@ class ConsolePort(CableTermination, ComponentModel):
     )
     connection_status = models.NullBooleanField(
         choices=CONNECTION_STATUS_CHOICES,
-        default=CONNECTION_STATUS_CONNECTED
+        blank=True
     )
 
     objects = DeviceComponentManager()
@@ -1792,7 +1792,7 @@ class PowerPort(CableTermination, ComponentModel):
     )
     connection_status = models.NullBooleanField(
         choices=CONNECTION_STATUS_CHOICES,
-        default=CONNECTION_STATUS_CONNECTED
+        blank=True
     )
 
     objects = DeviceComponentManager()
@@ -1897,7 +1897,7 @@ class Interface(CableTermination, ComponentModel):
     )
     connection_status = models.NullBooleanField(
         choices=CONNECTION_STATUS_CHOICES,
-        default=CONNECTION_STATUS_CONNECTED
+        blank=True
     )
     lag = models.ForeignKey(
         to='self',
@@ -2554,7 +2554,7 @@ class Cable(ChangeLoggedModel):
             ))
 
         # Virtual interfaces cannot be connected
-        endpoint_a, endpoint_b = self.get_path_endpoints()
+        endpoint_a, endpoint_b, _ = self.get_path_endpoints()
         if (
             (
                 isinstance(endpoint_a, Interface) and
@@ -2600,42 +2600,18 @@ class Cable(ChangeLoggedModel):
         Traverse both ends of a cable path and return its connected endpoints. Note that one or both endpoints may be
         None.
         """
-        def trace_cable(termination, position=1):
-
-            # Given a front port, follow the cable connected to the corresponding rear port/position
-            if isinstance(termination, FrontPort):
-                peer_port = termination.rear_port
-                position = termination.rear_port_position
-
-            # Given a rear port/position, follow the cable connected to the corresponding front port
-            elif isinstance(termination, RearPort):
-                if position not in range(1, termination.positions + 1):
-                    raise Exception("Invalid position for {} ({} positions): {})".format(
-                        termination, termination.positions, position
-                    ))
-                peer_port = FrontPort.objects.get(
-                    rear_port=termination,
-                    rear_port_position=position,
-                )
-                position = 1
+        a_path = self.termination_a.trace()
+        b_path = self.termination_b.trace()
 
-            # Termination is not a pass-through port, so we've reached the end of the path
-            else:
-                return termination
-
-            # Find the cable (if any) attached to the peer port
-            next_cable = peer_port.cable
-
-            # If no cable exists, return None
-            if next_cable is None:
-                return None
-
-            far_end = next_cable.termination_b if next_cable.termination_a == peer_port else next_cable.termination_a
-
-            # Return the far side termination of the cable
-            return trace_cable(far_end, position)
+        # Determine overall path status (connected or planned)
+        cables = [segment[1] for segment in a_path + b_path]
+        if all(cables) and all([c.status for c in cables]):
+            path_status = CONNECTION_STATUS_CONNECTED
+        else:
+            path_status = CONNECTION_STATUS_PLANNED
 
-        return trace_cable(self.termination_a), trace_cable(self.termination_b)
+        # (A path end, B path end, connected/planned)
+        return a_path[-1][2], b_path[-1][2], path_status
 
 
 #

netbox/dcim/signals.py

@@ -23,26 +23,35 @@ def clear_virtualchassis_members(instance, **kwargs):
 
 @receiver(post_save, sender=Cable)
 def update_connected_endpoints(instance, **kwargs):
+    """
+    When a Cable is saved, check for and update its two connected endpoints
+    """
 
     # Cache the Cable on its two termination points
-    instance.termination_a.cable = instance
-    instance.termination_a.save()
-    instance.termination_b.cable = instance
-    instance.termination_b.save()
+    if instance.termination_a.cable != instance:
+        instance.termination_a.cable = instance
+        instance.termination_a.save()
+    if instance.termination_b.cable != instance:
+        instance.termination_b.cable = instance
+        instance.termination_b.save()
 
     # Check if this Cable has formed a complete path. If so, update both endpoints.
-    endpoint_a, endpoint_b = instance.get_path_endpoints()
+    endpoint_a, endpoint_b, path_status = instance.get_path_endpoints()
     if endpoint_a is not None and endpoint_b is not None:
         endpoint_a.connected_endpoint = endpoint_b
-        endpoint_a.connection_status = True
+        endpoint_a.connection_status = path_status
         endpoint_a.save()
         endpoint_b.connected_endpoint = endpoint_a
-        endpoint_b.connection_status = True
+        endpoint_b.connection_status = path_status
         endpoint_b.save()
 
 
 @receiver(pre_delete, sender=Cable)
 def nullify_connected_endpoints(instance, **kwargs):
+    """
+    When a Cable is deleted, check for and update its two connected endpoints
+    """
+    endpoint_a, endpoint_b, _ = instance.get_path_endpoints()
 
     # Disassociate the Cable from its termination points
     if instance.termination_a is not None:
@@ -53,7 +62,6 @@ def nullify_connected_endpoints(instance, **kwargs):
         instance.termination_b.save()
 
     # If this Cable was part of a complete path, tear it down
-    endpoint_a, endpoint_b = instance.get_path_endpoints()
     if endpoint_a is not None and endpoint_b is not None:
         endpoint_a.connected_endpoint = None
         endpoint_a.connection_status = None

netbox/dcim/tests/test_models.py

@@ -1,5 +1,6 @@
 from django.test import TestCase
 
+from dcim.constants import *
 from dcim.models import *
 
 
@@ -252,3 +253,95 @@ class CableTestCase(TestCase):
         cable = Cable(termination_a=self.interface2, termination_b=virtual_interface)
         with self.assertRaises(ValidationError):
             cable.clean()
+
+
+class CablePathTestCase(TestCase):
+
+    def setUp(self):
+
+        site = Site.objects.create(name='Test Site 1', slug='test-site-1')
+        manufacturer = Manufacturer.objects.create(name='Test Manufacturer 1', slug='test-manufacturer-1')
+        devicetype = DeviceType.objects.create(
+            manufacturer=manufacturer, model='Test Device Type 1', slug='test-device-type-1'
+        )
+        devicerole = DeviceRole.objects.create(
+            name='Test Device Role 1', slug='test-device-role-1', color='ff0000'
+        )
+        self.device1 = Device.objects.create(
+            device_type=devicetype, device_role=devicerole, name='Test Device 1', site=site
+        )
+        self.device2 = Device.objects.create(
+            device_type=devicetype, device_role=devicerole, name='Test Device 2', site=site
+        )
+        self.interface1 = Interface.objects.create(device=self.device1, name='eth0')
+        self.interface2 = Interface.objects.create(device=self.device2, name='eth0')
+        self.panel1 = Device.objects.create(
+            device_type=devicetype, device_role=devicerole, name='Test Panel 1', site=site
+        )
+        self.panel2 = Device.objects.create(
+            device_type=devicetype, device_role=devicerole, name='Test Panel 2', site=site
+        )
+        self.rear_port1 = RearPort.objects.create(
+            device=self.panel1, name='Rear Port 1', type=PORT_TYPE_8P8C
+        )
+        self.front_port1 = FrontPort.objects.create(
+            device=self.panel1, name='Front Port 1', type=PORT_TYPE_8P8C, rear_port=self.rear_port1
+        )
+        self.rear_port2 = RearPort.objects.create(
+            device=self.panel2, name='Rear Port 2', type=PORT_TYPE_8P8C
+        )
+        self.front_port2 = FrontPort.objects.create(
+            device=self.panel2, name='Front Port 2', type=PORT_TYPE_8P8C, rear_port=self.rear_port2
+        )
+
+    def test_path_completion(self):
+
+        # First segment
+        cable1 = Cable(termination_a=self.interface1, termination_b=self.front_port1)
+        cable1.save()
+        interface1 = Interface.objects.get(pk=self.interface1.pk)
+        self.assertIsNone(interface1.connected_endpoint)
+        self.assertIsNone(interface1.connection_status)
+
+        # Second segment
+        cable2 = Cable(termination_a=self.rear_port1, termination_b=self.rear_port2)
+        cable2.save()
+        interface1 = Interface.objects.get(pk=self.interface1.pk)
+        self.assertIsNone(interface1.connected_endpoint)
+        self.assertIsNone(interface1.connection_status)
+
+        # Third segment
+        cable3 = Cable(termination_a=self.front_port2, termination_b=self.interface2, status=CONNECTION_STATUS_PLANNED)
+        cable3.save()
+        interface1 = Interface.objects.get(pk=self.interface1.pk)
+        self.assertEqual(interface1.connected_endpoint, self.interface2)
+        self.assertEqual(interface1.connection_status, CONNECTION_STATUS_PLANNED)
+
+        # Switch third segment from planned to connected
+        cable3.status = CONNECTION_STATUS_CONNECTED
+        cable3.save()
+        interface1 = Interface.objects.get(pk=self.interface1.pk)
+        self.assertEqual(interface1.connected_endpoint, self.interface2)
+        self.assertEqual(interface1.connection_status, CONNECTION_STATUS_CONNECTED)
+
+    def test_path_teardown(self):
+
+        # Build the path
+        cable1 = Cable(termination_a=self.interface1, termination_b=self.front_port1)
+        cable1.save()
+        cable2 = Cable(termination_a=self.rear_port1, termination_b=self.rear_port2)
+        cable2.save()
+        cable3 = Cable(termination_a=self.front_port2, termination_b=self.interface2)
+        cable3.save()
+        interface1 = Interface.objects.get(pk=self.interface1.pk)
+        self.assertEqual(interface1.connected_endpoint, self.interface2)
+        self.assertEqual(interface1.connection_status, CONNECTION_STATUS_CONNECTED)
+
+        # Remove a cable
+        cable2.delete()
+        interface1 = Interface.objects.get(pk=self.interface1.pk)
+        self.assertIsNone(interface1.connected_endpoint)
+        self.assertIsNone(interface1.connection_status)
+        interface2 = Interface.objects.get(pk=self.interface2.pk)
+        self.assertIsNone(interface2.connected_endpoint)
+        self.assertIsNone(interface2.connection_status)

netbox/dcim/views.py

@@ -1625,7 +1625,7 @@ class CableTraceView(View):
 
         return render(request, 'dcim/cable_trace.html', {
             'obj': obj,
-            'trace': obj.trace(),
+            'trace': obj.trace(follow_circuits=True),
         })