Fixes #20432: Allow cablepaths with CircuitTerminations that have different parent Circuit's (#20770)

Author: DanSheps

netbox/dcim/models/cables.py

@@ -10,6 +10,7 @@
 from core.models import ObjectType
 from dcim.choices import *
 from dcim.constants import *
+from dcim.exceptions import UnsupportedCablePath
 from dcim.fields import PathField
 from dcim.utils import decompile_path_node, object_to_path_node
 from netbox.choices import ColorChoices
@@ -28,8 +29,6 @@
     'CableTermination',
 )
 
-from ..exceptions import UnsupportedCablePath
-
 trace_paths = Signal()
 
 
@@ -615,7 +614,7 @@ def from_origin(cls, terminations):
         Cable or WirelessLink connects (interfaces, console ports, circuit termination, etc.). All terminations must be
         of the same type and must belong to the same parent object.
         """
-        from circuits.models import CircuitTermination
+        from circuits.models import CircuitTermination, Circuit
 
         if not terminations:
             return None
@@ -637,8 +636,11 @@ def from_origin(cls, terminations):
                 raise UnsupportedCablePath(_("All mid-span terminations must have the same termination type"))
 
             # All mid-span terminations must all be attached to the same device
-            if (not isinstance(terminations[0], PathEndpoint) and not
-                    all(t.parent_object == terminations[0].parent_object for t in terminations[1:])):
+            if (
+                not isinstance(terminations[0], PathEndpoint) and
+                not isinstance(terminations[0].parent_object, Circuit) and
+                not all(t.parent_object == terminations[0].parent_object for t in terminations[1:])
+            ):
                 raise UnsupportedCablePath(_("All mid-span terminations must have the same parent object"))
 
             # Check for a split path (e.g. rear port fanning out to multiple front ports with
@@ -782,32 +784,39 @@ def from_origin(cls, terminations):
 
             elif isinstance(remote_terminations[0], CircuitTermination):
                 # Follow a CircuitTermination to its corresponding CircuitTermination (A to Z or vice versa)
-                if len(remote_terminations) > 1:
-                    is_split = True
-                    break
-                circuit_termination = CircuitTermination.objects.filter(
-                    circuit=remote_terminations[0].circuit,
-                    term_side='Z' if remote_terminations[0].term_side == 'A' else 'A'
-                ).first()
-                if circuit_termination is None:
+                qs = Q()
+                for remote_termination in remote_terminations:
+                    qs |= Q(
+                        circuit=remote_termination.circuit,
+                        term_side='Z' if remote_termination.term_side == 'A' else 'A'
+                    )
+
+                # Get all circuit terminations
+                circuit_terminations = CircuitTermination.objects.filter(qs)
+
+                if not circuit_terminations.exists():
                     break
-                elif circuit_termination._provider_network:
+                elif all([ct._provider_network for ct in circuit_terminations]):
                     # Circuit terminates to a ProviderNetwork
                     path.extend([
-                        [object_to_path_node(circuit_termination)],
-                        [object_to_path_node(circuit_termination._provider_network)],
+                        [object_to_path_node(ct) for ct in circuit_terminations],
+                        [object_to_path_node(ct._provider_network) for ct in circuit_terminations],
                     ])
                     is_complete = True
                     break
-                elif circuit_termination.termination and not circuit_termination.cable:
+                elif all([ct.termination and not ct.cable for ct in circuit_terminations]):
                     # Circuit terminates to a Region/Site/etc.
                     path.extend([
-                        [object_to_path_node(circuit_termination)],
-                        [object_to_path_node(circuit_termination.termination)],
+                        [object_to_path_node(ct) for ct in circuit_terminations],
+                        [object_to_path_node(ct.termination) for ct in circuit_terminations],
                     ])
                     break
+                elif any([ct.cable in links for ct in circuit_terminations]):
+                    # No valid path
+                    is_split = True
+                    break
 
-                terminations = [circuit_termination]
+                terminations = circuit_terminations
 
             else:
                 # Check for non-symmetric path

netbox/dcim/tests/test_cablepaths.py

@@ -2270,6 +2270,80 @@ def test_222_single_path_via_multiple_singleposition_rear_ports(self):
         CableTraceSVG(interface1).render()
         CableTraceSVG(interface2).render()
 
+    def test_223_interface_to_interface_via_multiple_circuit_terminations(self):
+        provider = Provider.objects.first()
+        circuit_type = CircuitType.objects.first()
+        circuit1 = self.circuit
+        circuit2 = Circuit.objects.create(provider=provider, type=circuit_type, cid='Circuit 2')
+        interface1 = Interface.objects.create(device=self.device, name='Interface 1')
+        interface2 = Interface.objects.create(device=self.device, name='Interface 2')
+        circuittermination1_A = CircuitTermination.objects.create(
+            circuit=circuit1,
+            termination=self.site,
+            term_side='A'
+        )
+        circuittermination1_Z = CircuitTermination.objects.create(
+            circuit=circuit1,
+            termination=self.site,
+            term_side='Z'
+        )
+        circuittermination2_A = CircuitTermination.objects.create(
+            circuit=circuit2,
+            termination=self.site,
+            term_side='A'
+        )
+        circuittermination2_Z = CircuitTermination.objects.create(
+            circuit=circuit2,
+            termination=self.site,
+            term_side='Z'
+        )
+
+        # Create cables
+        cable1 = Cable(
+            a_terminations=[interface1],
+            b_terminations=[circuittermination1_A, circuittermination2_A]
+        )
+        cable2 = Cable(
+            a_terminations=[interface2],
+            b_terminations=[circuittermination1_Z, circuittermination2_Z]
+        )
+        cable1.save()
+        cable2.save()
+
+        self.assertEqual(CablePath.objects.count(), 2)
+
+        path1 = self.assertPathExists(
+            (
+                interface1,
+                cable1,
+                (circuittermination1_A, circuittermination2_A),
+                (circuittermination1_Z, circuittermination2_Z),
+                cable2,
+                interface2
+
+            ),
+            is_active=True,
+            is_complete=True,
+        )
+        interface1.refresh_from_db()
+        self.assertPathIsSet(interface1, path1)
+
+        path2 = self.assertPathExists(
+            (
+                interface2,
+                cable2,
+                (circuittermination1_Z, circuittermination2_Z),
+                (circuittermination1_A, circuittermination2_A),
+                cable1,
+                interface1
+
+            ),
+            is_active=True,
+            is_complete=True,
+        )
+        interface2.refresh_from_db()
+        self.assertPathIsSet(interface2, path2)
+
     def test_301_create_path_via_existing_cable(self):
         """
         [IF1] --C1-- [FP1] [RP1] --C2-- [RP2] [FP2] --C3-- [IF2]
@@ -2510,3 +2584,33 @@ def test_401_exclude_midspan_devices(self):
             is_active=True
         )
         self.assertEqual(CablePath.objects.count(), 0)
+
+    def test_402_exclude_circuit_loopback(self):
+        interface = Interface.objects.create(device=self.device, name='Interface 1')
+        circuittermination1 = CircuitTermination.objects.create(
+            circuit=self.circuit,
+            termination=self.site,
+            term_side='A'
+        )
+        circuittermination2 = CircuitTermination.objects.create(
+            circuit=self.circuit,
+            termination=self.site,
+            term_side='Z'
+        )
+
+        # Create cables
+        cable = Cable(
+            a_terminations=[interface],
+            b_terminations=[circuittermination1, circuittermination2]
+        )
+        cable.save()
+
+        path = self.assertPathExists(
+            (interface, cable, (circuittermination1, circuittermination2)),
+            is_active=True,
+            is_complete=False,
+            is_split=True
+        )
+        self.assertEqual(CablePath.objects.count(), 1)
+        interface.refresh_from_db()
+        self.assertPathIsSet(interface, path)