netbox/netbox/netbox/api/serializers/base.py

114 lines
3.9 KiB
Python

from functools import cached_property
from rest_framework import serializers
from rest_framework.utils.serializer_helpers import BindingDict
from drf_spectacular.utils import extend_schema_field
from drf_spectacular.types import OpenApiTypes
from utilities.api import get_related_object_by_attrs
from .fields import NetBoxAPIHyperlinkedIdentityField, NetBoxURLHyperlinkedIdentityField
__all__ = (
'BaseModelSerializer',
'ValidatedModelSerializer',
)
class BaseModelSerializer(serializers.ModelSerializer):
url = NetBoxAPIHyperlinkedIdentityField()
display_url = NetBoxURLHyperlinkedIdentityField()
display = serializers.SerializerMethodField(read_only=True)
def __init__(self, *args, nested=False, fields=None, **kwargs):
"""
Extends the base __init__() method to support dynamic fields.
:param nested: Set to True if this serializer is being employed within a parent serializer
:param fields: An iterable of fields to include when rendering the serialized object, If nested is
True but no fields are specified, Meta.brief_fields will be used.
"""
self.nested = nested
self._requested_fields = fields
# Disable validators for nested objects (which already exist)
if self.nested:
self.validators = []
# If this serializer is nested but no fields have been specified,
# default to using Meta.brief_fields (if set)
if self.nested and not fields:
self._requested_fields = getattr(self.Meta, 'brief_fields', None)
super().__init__(*args, **kwargs)
def to_internal_value(self, data):
# If initialized as a nested serializer, we should expect to receive the attrs or PK
# identifying a related object.
if self.nested:
queryset = self.Meta.model.objects.all()
return get_related_object_by_attrs(queryset, data)
return super().to_internal_value(data)
@cached_property
def fields(self):
"""
Override the fields property to check for requested fields. If defined,
return only the applicable fields.
"""
if not self._requested_fields:
return super().fields
fields = BindingDict(self)
for key, value in self.get_fields().items():
if key in self._requested_fields:
fields[key] = value
return fields
@extend_schema_field(OpenApiTypes.STR)
def get_display(self, obj):
return str(obj)
class ValidatedModelSerializer(BaseModelSerializer):
"""
Extends the built-in ModelSerializer to enforce calling full_clean() on a copy of the associated instance during
validation. (DRF does not do this by default; see https://github.com/encode/django-rest-framework/issues/3144)
"""
# Bypass DRF's built-in validation of unique constraints due to DRF bug #9410. Rely instead
# on our own custom model validation (below).
def get_unique_together_constraints(self, model):
return []
def validate(self, data):
# Skip validation if we're being used to represent a nested object
if self.nested:
return data
attrs = data.copy()
# Remove custom field data (if any) prior to model validation
attrs.pop('custom_fields', None)
# Skip ManyToManyFields
opts = self.Meta.model._meta
m2m_values = {}
for field in [*opts.local_many_to_many, *opts.related_objects]:
if field.name in attrs:
m2m_values[field.name] = attrs.pop(field.name)
# Run clean() on an instance of the model
if self.instance is None:
instance = self.Meta.model(**attrs)
else:
instance = self.instance
for k, v in attrs.items():
setattr(instance, k, v)
instance._m2m_values = m2m_values
instance.full_clean()
return data