Files
NetBox-Export/netbox_export/services/graph.py
T

217 lines
8.1 KiB
Python

from __future__ import annotations
from collections import deque
from django.apps import apps
from django.contrib.contenttypes.fields import GenericForeignKey
from django.contrib.contenttypes.models import ContentType
from django.db import models
from .codec import object_key
from .exceptions import GraphLimitError
EXCLUDED_APP_LABELS = {
"account",
"admin",
"auth",
"contenttypes",
"sessions",
"users",
"netbox_export",
}
EXCLUDED_MODELS = {
"core.job",
"core.objectchange",
"extras.eventrule",
"extras.journalentry",
"extras.notification",
"extras.notificationgroup",
"extras.savedfilter",
"extras.subscription",
}
SCOPE_LINK_FIELDS = {"tenant", "site", "location", "region"}
PEER_CONTAINER_MODELS = {"dcim.cable", "circuits.circuit", "circuits.virtualcircuit"}
def is_exportable_model(model) -> bool:
opts = model._meta
return bool(
opts.managed
and not opts.abstract
and not opts.proxy
and not opts.auto_created
and opts.app_label not in EXCLUDED_APP_LABELS
and opts.label_lower not in EXCLUDED_MODELS
)
def exportable_models():
return tuple(model for model in apps.get_models() if is_exportable_model(model))
def _descendants(obj):
if hasattr(obj, "get_descendants"):
return list(obj.get_descendants(include_self=True))
return [obj]
def seed_scope(scope_type: str, scope_id: int):
from dcim.models import Location, Region, Site
from tenancy.models import Tenant, TenantGroup
models_by_scope = {
"tenant_group": TenantGroup,
"tenant": Tenant,
"region": Region,
"site": Site,
"location": Location,
}
model = models_by_scope[scope_type]
root = model.objects.get(pk=scope_id)
seeds = _descendants(root)
if scope_type == "tenant_group":
group_ids = [obj.pk for obj in seeds]
seeds.extend(Tenant.objects.filter(group_id__in=group_ids))
elif scope_type == "region":
region_ids = [obj.pk for obj in seeds]
seeds.extend(Site.objects.filter(region_id__in=region_ids))
return root, seeds
class ObjectGraph:
"""Collect scoped objects first and their forward dependencies second."""
def __init__(self, max_objects: int):
self.max_objects = max_objects
self.members: dict[str, models.Model] = {}
self.dependencies: dict[str, models.Model] = {}
@property
def objects(self) -> dict[str, models.Model]:
return {**self.members, **self.dependencies}
def _check_limit(self):
if len(self.objects) > self.max_objects:
raise GraphLimitError(
f"Der Export würde mehr als {self.max_objects} Objekte enthalten. "
"Bitte den Bereich verkleinern oder max_objects erhöhen."
)
def add_member(self, obj) -> bool:
key = object_key(obj)
if key in self.members:
return False
self.dependencies.pop(key, None)
self.members[key] = obj
self._check_limit()
return True
def add_dependency(self, obj) -> bool:
key = object_key(obj)
if key in self.members or key in self.dependencies or not is_exportable_model(type(obj)):
return False
self.dependencies[key] = obj
self._check_limit()
return True
def collect(self, seeds):
queue = deque()
for obj in seeds:
if self.add_member(obj):
queue.append(obj)
models_to_scan = exportable_models()
while True:
while queue:
parent = queue.popleft()
parent_model = type(parent)
parent_ct = ContentType.objects.get_for_model(parent_model)
for candidate_model in models_to_scan:
query = models.Q()
for field in candidate_model._meta.concrete_fields:
if not isinstance(field, (models.ForeignKey, models.OneToOneField)):
continue
if field.remote_field.model is not parent_model:
continue
if (
field.remote_field.on_delete not in (models.CASCADE, models.PROTECT)
and field.name not in SCOPE_LINK_FIELDS
):
continue
query |= models.Q(**{field.attname: parent.pk})
for field in candidate_model._meta.private_fields:
if isinstance(field, GenericForeignKey):
query |= models.Q(**{field.ct_field: parent_ct, field.fk_field: parent.pk})
if not query:
continue
for child in candidate_model.objects.filter(query).distinct().iterator():
if self.add_member(child):
queue.append(child)
promoted = False
for obj in list(self.members.values()):
for field in obj._meta.concrete_fields:
if not isinstance(field, (models.ForeignKey, models.OneToOneField)):
continue
related = getattr(obj, field.name, None)
if related is None or related._meta.label_lower not in PEER_CONTAINER_MODELS:
continue
if self.add_member(related):
queue.append(related)
promoted = True
if not promoted:
break
dependency_queue = deque(self.members.values())
scanned = set()
while dependency_queue:
obj = dependency_queue.popleft()
key = object_key(obj)
if key in scanned:
continue
scanned.add(key)
related_objects = []
for field in obj._meta.concrete_fields:
if isinstance(field, (models.ForeignKey, models.OneToOneField)):
related = getattr(obj, field.name, None)
if related is not None:
related_objects.append(related)
for field in obj._meta.private_fields:
if isinstance(field, GenericForeignKey):
related = getattr(obj, field.name, None)
if related is not None:
related_objects.append(related)
for field in obj._meta.many_to_many:
try:
related_objects.extend(getattr(obj, field.name).all())
except (AttributeError, TypeError):
pass
if hasattr(obj, "custom_field_data"):
from extras.models import CustomField
custom_fields = list(CustomField.objects.get_for_model(type(obj)))
related_objects.extend(custom_fields)
for custom_field in custom_fields:
if custom_field.type not in ("object", "multiobject") or not custom_field.related_object_type:
continue
raw_value = obj.custom_field_data.get(custom_field.name)
if raw_value in (None, "", []):
continue
target_model = custom_field.related_object_type.model_class()
target_ids = raw_value if custom_field.type == "multiobject" else [raw_value]
related_objects.extend(target_model._default_manager.filter(pk__in=target_ids))
if (
obj._meta.label_lower == "extras.customfield"
and obj.type in ("object", "multiobject")
and obj.related_object_type
and obj.default not in (None, "", [])
):
target_model = obj.related_object_type.model_class()
target_ids = obj.default if obj.type == "multiobject" else [obj.default]
related_objects.extend(target_model._default_manager.filter(pk__in=target_ids))
for related in related_objects:
if self.add_dependency(related):
dependency_queue.append(related)
return self