Initial work on #6087

netbox/ipam/models/ip.py

@@ -293,6 +293,16 @@ class Prefix(PrimaryModel):
         blank=True
     )
 
+    # Cached depth & child counts
+    _depth = models.PositiveSmallIntegerField(
+        default=0,
+        editable=False
+    )
+    _children = models.PositiveBigIntegerField(
+        default=0,
+        editable=False
+    )
+
     objects = PrefixQuerySet.as_manager()
 
     csv_headers = [
@@ -306,6 +316,13 @@ class Prefix(PrimaryModel):
         ordering = (F('vrf').asc(nulls_first=True), 'prefix', 'pk')  # (vrf, prefix) may be non-unique
         verbose_name_plural = 'prefixes'
 
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        # Cache the original prefix and VRF so we can check if they have changed on post_save
+        self._prefix = self.prefix
+        self._vrf = self.vrf
+
     def __str__(self):
         return str(self.prefix)
 
@@ -373,6 +390,14 @@ class Prefix(PrimaryModel):
             return self.prefix.version
         return None
 
+    @property
+    def depth(self):
+        return self._depth
+
+    @property
+    def children(self):
+        return self._children
+
     def _set_prefix_length(self, value):
         """
         Expose the IPNetwork object's prefixlen attribute on the parent model so that it can be manipulated directly,
@@ -385,6 +410,26 @@ class Prefix(PrimaryModel):
     def get_status_class(self):
         return PrefixStatusChoices.CSS_CLASSES.get(self.status)
 
+    def get_parents(self, include_self=False):
+        """
+        Return all containing Prefixes in the hierarchy.
+        """
+        lookup = 'net_contains_or_equals' if include_self else 'net_contains'
+        return Prefix.objects.filter(**{
+            'vrf': self.vrf,
+            f'prefix__{lookup}': self.prefix
+        })
+
+    def get_children(self, include_self=False):
+        """
+        Return all covered Prefixes in the hierarchy.
+        """
+        lookup = 'net_contained_or_equal' if include_self else 'net_contained'
+        return Prefix.objects.filter(**{
+            'vrf': self.vrf,
+            f'prefix__{lookup}': self.prefix
+        })
+
     def get_duplicates(self):
         return Prefix.objects.filter(vrf=self.vrf, prefix=str(self.prefix)).exclude(pk=self.pk)