feat: Add BGP Sessions tab to Interface detail pages

- Add InterfaceBGPSessionsView class with tab registration for displaying BGP sessions associated with interfaces via their IP addresses
- Fix GenericForeignKey filtering by using ContentType and assigned_object_type/id fields instead of direct assigned_object lookup
- Add necessary imports for Interface and ContentType models

Author: Kani999

netbox_bgp/template_content.py

@@ -1,5 +1,12 @@
-from dcim.models import Device, Site
+from dcim.models import Device, Interface, Site
 from django.conf import settings
+<<<<<<< HEAD
+=======
+from django.contrib.contenttypes.models import ContentType
+from django.db.models import Q, QuerySet
+from django.http import HttpRequest
+from ipam.models import ASN, IPAddress
+>>>>>>> ed30fbc (feat: Add BGP Sessions tab to Interface detail pages)
 from netbox.plugins import PluginTemplateExtension
 from netbox.views.generic import ObjectChildrenView
 from utilities.views import ViewTab, register_model_view
@@ -164,6 +171,43 @@ def get_children(self, request: HttpRequest, parent: ASN) -> QuerySet[BGPSession
         return ASNBGPSessionsView._get_asn_bgp_sessions(parent)
 
 
+@register_model_view(Interface, name="bgp-sessions", path="bgp-sessions")
+class InterfaceBGPSessionsView(generic.ObjectChildrenView):
+    """View to display BGP sessions associated with an interface."""
+
+    queryset = Interface.objects.all()
+    child_model = BGPSession
+    filterset = BGPSessionFilterSet
+    table = BGPSessionTable
+    template_name = "generic/object_children.html"
+    hide_if_empty = False
+
+    @staticmethod
+    def _get_interface_bgp_sessions(interface: Interface) -> QuerySet[BGPSession]:
+        """Helper to get BGP sessions related to an interface via its IP addresses."""
+        ct = ContentType.objects.get_for_model(Interface)
+        ips = IPAddress.objects.filter(
+            assigned_object_type=ct, assigned_object_id=interface.pk
+        )
+        return BGPSession.objects.filter(
+            Q(local_address__in=ips) | Q(remote_address__in=ips)
+        ).distinct()
+
+    tab = ViewTab(
+        label="BGP Sessions",
+        badge=lambda obj: InterfaceBGPSessionsView._get_interface_bgp_sessions(
+            obj
+        ).count(),
+        permission="netbox_bgp.view_bgpsession",
+    )
+
+    def get_children(
+        self, request: HttpRequest, parent: Interface
+    ) -> QuerySet[BGPSession]:
+        """Get BGP sessions for the interface."""
+        return InterfaceBGPSessionsView._get_interface_bgp_sessions(parent)
+
+
 # Register only when device_ext_page is set to 'tab';
 class DeviceBGPSessionsView(generic.ObjectChildrenView):
     """View to display BGP sessions associated with a device."""