feat: automate patchpanel mappings and cable tenancy

netbox_utilities/tests/test_patchpanel.py

@@ -0,0 +1,29 @@
+from types import SimpleNamespace
+
+from django.test import SimpleTestCase
+
+from netbox_utilities.patchpanel import is_patchpanel, pair_ports
+
+
+def port(pk, name):
+    return SimpleNamespace(pk=pk, name=name)
+
+
+class PatchpanelPairingTest(SimpleTestCase):
+    def test_detects_patchpanel_role_case_insensitively(self):
+        self.assertTrue(is_patchpanel(SimpleNamespace(role=SimpleNamespace(name="Patchpanel"))))
+        self.assertTrue(is_patchpanel(SimpleNamespace(role=SimpleNamespace(name="PATCHPANEL"))))
+        self.assertFalse(is_patchpanel(SimpleNamespace(role=SimpleNamespace(name="Switch"))))
+
+    def test_pairs_front_and_rear_ports_in_natural_order(self):
+        front_ports = [port(10, "10"), port(2, "2"), port(1, "1")]
+        rear_ports = [port(102, "Rear 2"), port(110, "Rear 10"), port(101, "Rear 1")]
+
+        pairs = pair_ports(front_ports, rear_ports)
+
+        self.assertEqual([(front.pk, rear.pk) for front, rear in pairs], [(1, 101), (2, 102), (10, 110)])
+
+    def test_leaves_unmatched_ports_without_a_mapping(self):
+        pairs = pair_ports([port(1, "1"), port(2, "2")], [port(101, "1")])
+
+        self.assertEqual([(front.pk, rear.pk) for front, rear in pairs], [(1, 101)])

netbox_utilities/tests/test_tenant_autofill.py

@@ -5,7 +5,13 @@ from django import forms
 from django.test import SimpleTestCase
 from tenancy.models import TenantGroup
 
-from netbox_utilities.tenant_autofill import apply_tenant_autofill, infer_tenant_id, tenant_id_from_object
+from netbox_utilities.tenant_autofill import (
+    apply_cable_instance_tenant,
+    apply_tenant_autofill,
+    infer_tenant_id,
+    tenant_id_from_cable_terminations,
+    tenant_id_from_object,
+)
 from netbox_utilities.tenant_scope import ActiveTenantScope, active_tenant_scope
 
 
@@ -17,6 +23,11 @@ class FakeMeta:
         return [SimpleNamespace(name=name) for name in self.field_names]
 
 
+class FakeCableMeta(FakeMeta):
+    app_label = "dcim"
+    model_name = "cable"
+
+
 class FakeObject:
     def __init__(self, *, tenant_id=None, **relations):
         self.tenant_id = tenant_id
@@ -25,6 +36,14 @@ class FakeObject:
             setattr(self, name, value)
 
 
+class FakeCable(FakeObject):
+    def __init__(self, *, tenant_id=None, a_terminations=None, b_terminations=None):
+        super().__init__(tenant_id=tenant_id)
+        self._meta = FakeCableMeta("tenant")
+        self.a_terminations = a_terminations or []
+        self.b_terminations = b_terminations or []
+
+
 class FakeQuerySet:
     def __init__(self, model):
         self.model = model
@@ -50,6 +69,54 @@ class TenantAutofillTest(SimpleTestCase):
         finally:
             active_tenant_scope.reset(token)
 
+    def test_finds_common_cable_tenant_from_both_ends(self):
+        terminations = [FakeObject(device=FakeObject(tenant_id=42)), FakeObject(device=FakeObject(tenant_id=42))]
+
+        self.assertEqual(tenant_id_from_cable_terminations(terminations), 42)
+
+    def test_does_not_guess_when_cable_ends_have_different_tenants(self):
+        terminations = [FakeObject(device=FakeObject(tenant_id=42)), FakeObject(device=FakeObject(tenant_id=43))]
+
+        self.assertIsNone(tenant_id_from_cable_terminations(terminations))
+
+    def test_assigns_common_tenant_to_cable_instance(self):
+        cable = FakeCable(
+            a_terminations=[FakeObject(device=FakeObject(tenant_id=42))],
+            b_terminations=[FakeObject(device=FakeObject(tenant_id=42))],
+        )
+
+        self.assertEqual(apply_cable_instance_tenant(cable), 42)
+        self.assertEqual(cable.tenant_id, 42)
+
+    def test_prefers_cable_terminations_over_global_scope(self):
+        form = SimpleNamespace(
+            fields={"tenant": forms.IntegerField()},
+            initial={},
+            instance=FakeCable(a_terminations=[FakeObject(device=FakeObject(tenant_id=42))]),
+            is_bound=False,
+        )
+        token = active_tenant_scope.set(ActiveTenantScope("tenant", 17, frozenset({17})))
+        try:
+            self.assertEqual(infer_tenant_id(form), 42)
+        finally:
+            active_tenant_scope.reset(token)
+
+    def test_conflicting_cable_ends_do_not_fall_back_to_global_scope(self):
+        form = SimpleNamespace(
+            fields={"tenant": forms.IntegerField()},
+            initial={},
+            instance=FakeCable(
+                a_terminations=[FakeObject(device=FakeObject(tenant_id=42))],
+                b_terminations=[FakeObject(device=FakeObject(tenant_id=43))],
+            ),
+            is_bound=False,
+        )
+        token = active_tenant_scope.set(ActiveTenantScope("tenant", 17, frozenset({17})))
+        try:
+            self.assertIsNone(infer_tenant_id(form))
+        finally:
+            active_tenant_scope.reset(token)
+
     @patch("netbox_utilities.tenant_autofill._infer_group_id", return_value=None)
     @patch("netbox_utilities.tenant_autofill.infer_tenant_id", return_value=23)
     def test_prefills_and_marks_tenant_field(self, _infer_tenant_id, _infer_group_id):