Add support for finding all rear ports in a virtual chassis

Implements filter_virtual_chassis_member.
This also displays all rear ports on the master member of a virtual chassis.

netbox/dcim/filtersets.py

@@ -1596,6 +1596,7 @@ class FrontPortFilterSet(
         model = FrontPort
         fields = ['id', 'name', 'label', 'type', 'color', 'description', 'cable_end']
 
+
     def filter_virtual_chassis_member(self, queryset, name, value):
         try:
             vc_front_port_ids = []
@@ -1611,6 +1612,17 @@ class RearPortFilterSet(
     NetBoxModelFilterSet,
     CabledObjectFilterSet
 ):
+    virtual_chassis_member = MultiValueCharFilter(
+        method='filter_virtual_chassis_member',
+        field_name='name',
+        label=_('Virtual Chassis Rear Ports for Device')
+    )
+    virtual_chassis_member_id = MultiValueNumberFilter(
+        method='filter_virtual_chassis_member',
+        field_name='pk',
+        label=_('Virtual Chassis Rear Ports for Device (ID)')
+    )
+
     type = django_filters.MultipleChoiceFilter(
         choices=PortTypeChoices,
         null_value=None
@@ -1621,6 +1633,16 @@ class RearPortFilterSet(
         fields = ['id', 'name', 'label', 'type', 'color', 'positions', 'description', 'cable_end']
 
 
+    def filter_virtual_chassis_member(self, queryset, name, value):
+        try:
+            vc_rear_port_ids = []
+            for device in Device.objects.filter(**{f'{name}__in': value}):
+                vc_rear_port_ids.extend(device.vc_rear_ports(if_master=False).values_list('id', flat=True))
+            return queryset.filter(pk__in=vc_front_rear_ids)
+        except Device.DoesNotExist:
+            return queryset.none()
+
+
 class ModuleBayFilterSet(DeviceComponentFilterSet, NetBoxModelFilterSet):
 
     class Meta:

netbox/dcim/models/devices.py

@@ -1119,6 +1119,22 @@ class Device(
             filter |= Q(device__virtual_chassis=self.virtual_chassis)
         return FrontPort.objects.filter(filter)
 
+    @property
+    def rear_ports_count(self):
+        return self.vc_rear_ports().count()
+
+    def vc_rear_ports(self, if_master=True):
+        """
+        Return a QuerySet matching all RearPorts assigned to this Device or, if this Device is a VC master, to another
+        Device belonging to the same VirtualChassis.
+
+        :param if_master: If True, return VC member rear ports only if this Device is the VC master.
+        """
+        filter = Q(device=self)
+        if self.virtual_chassis and (self.virtual_chassis.master == self or not if_master):
+            filter |= Q(device__virtual_chassis=self.virtual_chassis)
+        return RearPort.objects.filter(filter)
+    
     def get_cables(self, pk_list=False):
         """
         Return a QuerySet or PK list matching all Cables connected to a component of this Device.