2475 lines
96 KiB
Python
2475 lines
96 KiB
Python
import copy
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import inspect
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import warnings
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from functools import partialmethod
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from itertools import chain
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import django
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from django.apps import apps
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from django.conf import settings
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from django.core import checks
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from django.core.exceptions import (
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NON_FIELD_ERRORS,
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FieldDoesNotExist,
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FieldError,
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MultipleObjectsReturned,
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ObjectDoesNotExist,
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ValidationError,
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)
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from django.db import (
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DJANGO_VERSION_PICKLE_KEY,
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DatabaseError,
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connection,
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connections,
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router,
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transaction,
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)
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from django.db.models import NOT_PROVIDED, ExpressionWrapper, IntegerField, Max, Value
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from django.db.models.constants import LOOKUP_SEP
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from django.db.models.constraints import CheckConstraint, UniqueConstraint
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from django.db.models.deletion import CASCADE, Collector
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from django.db.models.expressions import RawSQL
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from django.db.models.fields.related import (
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ForeignObjectRel,
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OneToOneField,
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lazy_related_operation,
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resolve_relation,
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)
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from django.db.models.functions import Coalesce
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from django.db.models.manager import Manager
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from django.db.models.options import Options
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from django.db.models.query import F, Q
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from django.db.models.signals import (
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class_prepared,
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post_init,
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post_save,
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pre_init,
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pre_save,
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)
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from django.db.models.utils import make_model_tuple
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from django.utils.encoding import force_str
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from django.utils.hashable import make_hashable
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from django.utils.text import capfirst, get_text_list
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from django.utils.translation import gettext_lazy as _
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class Deferred:
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def __repr__(self):
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return "<Deferred field>"
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def __str__(self):
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return "<Deferred field>"
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DEFERRED = Deferred()
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def subclass_exception(name, bases, module, attached_to):
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"""
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Create exception subclass. Used by ModelBase below.
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The exception is created in a way that allows it to be pickled, assuming
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that the returned exception class will be added as an attribute to the
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'attached_to' class.
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"""
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return type(
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name,
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bases,
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{
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"__module__": module,
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"__qualname__": "%s.%s" % (attached_to.__qualname__, name),
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},
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)
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def _has_contribute_to_class(value):
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# Only call contribute_to_class() if it's bound.
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return not inspect.isclass(value) and hasattr(value, "contribute_to_class")
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class ModelBase(type):
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"""Metaclass for all models."""
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def __new__(cls, name, bases, attrs, **kwargs):
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super_new = super().__new__
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# Also ensure initialization is only performed for subclasses of Model
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# (excluding Model class itself).
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parents = [b for b in bases if isinstance(b, ModelBase)]
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if not parents:
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return super_new(cls, name, bases, attrs)
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# Create the class.
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module = attrs.pop("__module__")
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new_attrs = {"__module__": module}
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classcell = attrs.pop("__classcell__", None)
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if classcell is not None:
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new_attrs["__classcell__"] = classcell
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attr_meta = attrs.pop("Meta", None)
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# Pass all attrs without a (Django-specific) contribute_to_class()
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# method to type.__new__() so that they're properly initialized
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# (i.e. __set_name__()).
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contributable_attrs = {}
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for obj_name, obj in attrs.items():
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if _has_contribute_to_class(obj):
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contributable_attrs[obj_name] = obj
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else:
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new_attrs[obj_name] = obj
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new_class = super_new(cls, name, bases, new_attrs, **kwargs)
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abstract = getattr(attr_meta, "abstract", False)
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meta = attr_meta or getattr(new_class, "Meta", None)
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base_meta = getattr(new_class, "_meta", None)
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app_label = None
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# Look for an application configuration to attach the model to.
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app_config = apps.get_containing_app_config(module)
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if getattr(meta, "app_label", None) is None:
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if app_config is None:
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if not abstract:
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raise RuntimeError(
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"Model class %s.%s doesn't declare an explicit "
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"app_label and isn't in an application in "
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"INSTALLED_APPS." % (module, name)
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)
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else:
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app_label = app_config.label
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new_class.add_to_class("_meta", Options(meta, app_label))
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if not abstract:
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new_class.add_to_class(
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"DoesNotExist",
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subclass_exception(
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"DoesNotExist",
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tuple(
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x.DoesNotExist
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for x in parents
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if hasattr(x, "_meta") and not x._meta.abstract
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)
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or (ObjectDoesNotExist,),
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module,
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attached_to=new_class,
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),
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)
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new_class.add_to_class(
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"MultipleObjectsReturned",
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subclass_exception(
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"MultipleObjectsReturned",
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tuple(
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x.MultipleObjectsReturned
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for x in parents
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if hasattr(x, "_meta") and not x._meta.abstract
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)
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or (MultipleObjectsReturned,),
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module,
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attached_to=new_class,
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),
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)
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if base_meta and not base_meta.abstract:
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# Non-abstract child classes inherit some attributes from their
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# non-abstract parent (unless an ABC comes before it in the
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# method resolution order).
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if not hasattr(meta, "ordering"):
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new_class._meta.ordering = base_meta.ordering
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if not hasattr(meta, "get_latest_by"):
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new_class._meta.get_latest_by = base_meta.get_latest_by
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is_proxy = new_class._meta.proxy
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# If the model is a proxy, ensure that the base class
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# hasn't been swapped out.
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if is_proxy and base_meta and base_meta.swapped:
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raise TypeError(
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"%s cannot proxy the swapped model '%s'." % (name, base_meta.swapped)
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)
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# Add remaining attributes (those with a contribute_to_class() method)
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# to the class.
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for obj_name, obj in contributable_attrs.items():
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new_class.add_to_class(obj_name, obj)
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# All the fields of any type declared on this model
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new_fields = chain(
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new_class._meta.local_fields,
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new_class._meta.local_many_to_many,
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new_class._meta.private_fields,
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)
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field_names = {f.name for f in new_fields}
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# Basic setup for proxy models.
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if is_proxy:
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base = None
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for parent in [kls for kls in parents if hasattr(kls, "_meta")]:
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if parent._meta.abstract:
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if parent._meta.fields:
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raise TypeError(
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"Abstract base class containing model fields not "
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"permitted for proxy model '%s'." % name
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)
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else:
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continue
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if base is None:
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base = parent
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elif parent._meta.concrete_model is not base._meta.concrete_model:
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raise TypeError(
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"Proxy model '%s' has more than one non-abstract model base "
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"class." % name
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)
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if base is None:
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raise TypeError(
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"Proxy model '%s' has no non-abstract model base class." % name
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)
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new_class._meta.setup_proxy(base)
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new_class._meta.concrete_model = base._meta.concrete_model
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else:
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new_class._meta.concrete_model = new_class
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# Collect the parent links for multi-table inheritance.
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parent_links = {}
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for base in reversed([new_class] + parents):
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# Conceptually equivalent to `if base is Model`.
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if not hasattr(base, "_meta"):
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continue
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# Skip concrete parent classes.
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if base != new_class and not base._meta.abstract:
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continue
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# Locate OneToOneField instances.
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for field in base._meta.local_fields:
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if isinstance(field, OneToOneField) and field.remote_field.parent_link:
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related = resolve_relation(new_class, field.remote_field.model)
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parent_links[make_model_tuple(related)] = field
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# Track fields inherited from base models.
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inherited_attributes = set()
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# Do the appropriate setup for any model parents.
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for base in new_class.mro():
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if base not in parents or not hasattr(base, "_meta"):
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# Things without _meta aren't functional models, so they're
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# uninteresting parents.
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inherited_attributes.update(base.__dict__)
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continue
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parent_fields = base._meta.local_fields + base._meta.local_many_to_many
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if not base._meta.abstract:
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# Check for clashes between locally declared fields and those
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# on the base classes.
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for field in parent_fields:
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if field.name in field_names:
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raise FieldError(
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"Local field %r in class %r clashes with field of "
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"the same name from base class %r."
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% (
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field.name,
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name,
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base.__name__,
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)
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)
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else:
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inherited_attributes.add(field.name)
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# Concrete classes...
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base = base._meta.concrete_model
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base_key = make_model_tuple(base)
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if base_key in parent_links:
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field = parent_links[base_key]
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elif not is_proxy:
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attr_name = "%s_ptr" % base._meta.model_name
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field = OneToOneField(
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base,
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on_delete=CASCADE,
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name=attr_name,
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auto_created=True,
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parent_link=True,
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)
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if attr_name in field_names:
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raise FieldError(
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"Auto-generated field '%s' in class %r for "
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"parent_link to base class %r clashes with "
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"declared field of the same name."
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% (
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attr_name,
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name,
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base.__name__,
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)
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)
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# Only add the ptr field if it's not already present;
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# e.g. migrations will already have it specified
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if not hasattr(new_class, attr_name):
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new_class.add_to_class(attr_name, field)
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else:
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field = None
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new_class._meta.parents[base] = field
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else:
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base_parents = base._meta.parents.copy()
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# Add fields from abstract base class if it wasn't overridden.
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for field in parent_fields:
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if (
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field.name not in field_names
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and field.name not in new_class.__dict__
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and field.name not in inherited_attributes
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):
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new_field = copy.deepcopy(field)
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new_class.add_to_class(field.name, new_field)
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# Replace parent links defined on this base by the new
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# field. It will be appropriately resolved if required.
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if field.one_to_one:
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for parent, parent_link in base_parents.items():
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if field == parent_link:
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base_parents[parent] = new_field
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# Pass any non-abstract parent classes onto child.
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new_class._meta.parents.update(base_parents)
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# Inherit private fields (like GenericForeignKey) from the parent
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# class
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for field in base._meta.private_fields:
|
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if field.name in field_names:
|
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if not base._meta.abstract:
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raise FieldError(
|
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"Local field %r in class %r clashes with field of "
|
|
"the same name from base class %r."
|
|
% (
|
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field.name,
|
|
name,
|
|
base.__name__,
|
|
)
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)
|
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else:
|
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field = copy.deepcopy(field)
|
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if not base._meta.abstract:
|
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field.mti_inherited = True
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new_class.add_to_class(field.name, field)
|
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# Copy indexes so that index names are unique when models extend an
|
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# abstract model.
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new_class._meta.indexes = [
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copy.deepcopy(idx) for idx in new_class._meta.indexes
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]
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if abstract:
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# Abstract base models can't be instantiated and don't appear in
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# the list of models for an app. We do the final setup for them a
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# little differently from normal models.
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attr_meta.abstract = False
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new_class.Meta = attr_meta
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return new_class
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new_class._prepare()
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new_class._meta.apps.register_model(new_class._meta.app_label, new_class)
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return new_class
|
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|
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def add_to_class(cls, name, value):
|
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if _has_contribute_to_class(value):
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value.contribute_to_class(cls, name)
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else:
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setattr(cls, name, value)
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|
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def _prepare(cls):
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"""Create some methods once self._meta has been populated."""
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opts = cls._meta
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opts._prepare(cls)
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if opts.order_with_respect_to:
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cls.get_next_in_order = partialmethod(
|
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cls._get_next_or_previous_in_order, is_next=True
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)
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cls.get_previous_in_order = partialmethod(
|
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cls._get_next_or_previous_in_order, is_next=False
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)
|
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# Defer creating accessors on the foreign class until it has been
|
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# created and registered. If remote_field is None, we're ordering
|
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# with respect to a GenericForeignKey and don't know what the
|
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# foreign class is - we'll add those accessors later in
|
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# contribute_to_class().
|
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if opts.order_with_respect_to.remote_field:
|
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wrt = opts.order_with_respect_to
|
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remote = wrt.remote_field.model
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lazy_related_operation(make_foreign_order_accessors, cls, remote)
|
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|
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# Give the class a docstring -- its definition.
|
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if cls.__doc__ is None:
|
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cls.__doc__ = "%s(%s)" % (
|
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cls.__name__,
|
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", ".join(f.name for f in opts.fields),
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)
|
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|
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get_absolute_url_override = settings.ABSOLUTE_URL_OVERRIDES.get(
|
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opts.label_lower
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)
|
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if get_absolute_url_override:
|
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setattr(cls, "get_absolute_url", get_absolute_url_override)
|
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|
|
if not opts.managers:
|
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if any(f.name == "objects" for f in opts.fields):
|
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raise ValueError(
|
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"Model %s must specify a custom Manager, because it has a "
|
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"field named 'objects'." % cls.__name__
|
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)
|
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manager = Manager()
|
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manager.auto_created = True
|
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cls.add_to_class("objects", manager)
|
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|
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# Set the name of _meta.indexes. This can't be done in
|
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# Options.contribute_to_class() because fields haven't been added to
|
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# the model at that point.
|
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for index in cls._meta.indexes:
|
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if not index.name:
|
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index.set_name_with_model(cls)
|
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|
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class_prepared.send(sender=cls)
|
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|
|
@property
|
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def _base_manager(cls):
|
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return cls._meta.base_manager
|
|
|
|
@property
|
|
def _default_manager(cls):
|
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return cls._meta.default_manager
|
|
|
|
|
|
class ModelStateFieldsCacheDescriptor:
|
|
def __get__(self, instance, cls=None):
|
|
if instance is None:
|
|
return self
|
|
res = instance.fields_cache = {}
|
|
return res
|
|
|
|
|
|
class ModelState:
|
|
"""Store model instance state."""
|
|
|
|
db = None
|
|
# If true, uniqueness validation checks will consider this a new, unsaved
|
|
# object. Necessary for correct validation of new instances of objects with
|
|
# explicit (non-auto) PKs. This impacts validation only; it has no effect
|
|
# on the actual save.
|
|
adding = True
|
|
fields_cache = ModelStateFieldsCacheDescriptor()
|
|
|
|
|
|
class Model(metaclass=ModelBase):
|
|
def __init__(self, *args, **kwargs):
|
|
# Alias some things as locals to avoid repeat global lookups
|
|
cls = self.__class__
|
|
opts = self._meta
|
|
_setattr = setattr
|
|
_DEFERRED = DEFERRED
|
|
if opts.abstract:
|
|
raise TypeError("Abstract models cannot be instantiated.")
|
|
|
|
pre_init.send(sender=cls, args=args, kwargs=kwargs)
|
|
|
|
# Set up the storage for instance state
|
|
self._state = ModelState()
|
|
|
|
# There is a rather weird disparity here; if kwargs, it's set, then args
|
|
# overrides it. It should be one or the other; don't duplicate the work
|
|
# The reason for the kwargs check is that standard iterator passes in by
|
|
# args, and instantiation for iteration is 33% faster.
|
|
if len(args) > len(opts.concrete_fields):
|
|
# Daft, but matches old exception sans the err msg.
|
|
raise IndexError("Number of args exceeds number of fields")
|
|
|
|
if not kwargs:
|
|
fields_iter = iter(opts.concrete_fields)
|
|
# The ordering of the zip calls matter - zip throws StopIteration
|
|
# when an iter throws it. So if the first iter throws it, the second
|
|
# is *not* consumed. We rely on this, so don't change the order
|
|
# without changing the logic.
|
|
for val, field in zip(args, fields_iter):
|
|
if val is _DEFERRED:
|
|
continue
|
|
_setattr(self, field.attname, val)
|
|
else:
|
|
# Slower, kwargs-ready version.
|
|
fields_iter = iter(opts.fields)
|
|
for val, field in zip(args, fields_iter):
|
|
if val is _DEFERRED:
|
|
continue
|
|
_setattr(self, field.attname, val)
|
|
if kwargs.pop(field.name, NOT_PROVIDED) is not NOT_PROVIDED:
|
|
raise TypeError(
|
|
f"{cls.__qualname__}() got both positional and "
|
|
f"keyword arguments for field '{field.name}'."
|
|
)
|
|
|
|
# Now we're left with the unprocessed fields that *must* come from
|
|
# keywords, or default.
|
|
|
|
for field in fields_iter:
|
|
is_related_object = False
|
|
# Virtual field
|
|
if field.attname not in kwargs and field.column is None:
|
|
continue
|
|
if kwargs:
|
|
if isinstance(field.remote_field, ForeignObjectRel):
|
|
try:
|
|
# Assume object instance was passed in.
|
|
rel_obj = kwargs.pop(field.name)
|
|
is_related_object = True
|
|
except KeyError:
|
|
try:
|
|
# Object instance wasn't passed in -- must be an ID.
|
|
val = kwargs.pop(field.attname)
|
|
except KeyError:
|
|
val = field.get_default()
|
|
else:
|
|
try:
|
|
val = kwargs.pop(field.attname)
|
|
except KeyError:
|
|
# This is done with an exception rather than the
|
|
# default argument on pop because we don't want
|
|
# get_default() to be evaluated, and then not used.
|
|
# Refs #12057.
|
|
val = field.get_default()
|
|
else:
|
|
val = field.get_default()
|
|
|
|
if is_related_object:
|
|
# If we are passed a related instance, set it using the
|
|
# field.name instead of field.attname (e.g. "user" instead of
|
|
# "user_id") so that the object gets properly cached (and type
|
|
# checked) by the RelatedObjectDescriptor.
|
|
if rel_obj is not _DEFERRED:
|
|
_setattr(self, field.name, rel_obj)
|
|
else:
|
|
if val is not _DEFERRED:
|
|
_setattr(self, field.attname, val)
|
|
|
|
if kwargs:
|
|
property_names = opts._property_names
|
|
unexpected = ()
|
|
for prop, value in kwargs.items():
|
|
# Any remaining kwargs must correspond to properties or virtual
|
|
# fields.
|
|
if prop in property_names:
|
|
if value is not _DEFERRED:
|
|
_setattr(self, prop, value)
|
|
else:
|
|
try:
|
|
opts.get_field(prop)
|
|
except FieldDoesNotExist:
|
|
unexpected += (prop,)
|
|
else:
|
|
if value is not _DEFERRED:
|
|
_setattr(self, prop, value)
|
|
if unexpected:
|
|
unexpected_names = ", ".join(repr(n) for n in unexpected)
|
|
raise TypeError(
|
|
f"{cls.__name__}() got unexpected keyword arguments: "
|
|
f"{unexpected_names}"
|
|
)
|
|
super().__init__()
|
|
post_init.send(sender=cls, instance=self)
|
|
|
|
@classmethod
|
|
def from_db(cls, db, field_names, values):
|
|
if len(values) != len(cls._meta.concrete_fields):
|
|
values_iter = iter(values)
|
|
values = [
|
|
next(values_iter) if f.attname in field_names else DEFERRED
|
|
for f in cls._meta.concrete_fields
|
|
]
|
|
new = cls(*values)
|
|
new._state.adding = False
|
|
new._state.db = db
|
|
return new
|
|
|
|
def __repr__(self):
|
|
return "<%s: %s>" % (self.__class__.__name__, self)
|
|
|
|
def __str__(self):
|
|
return "%s object (%s)" % (self.__class__.__name__, self.pk)
|
|
|
|
def __eq__(self, other):
|
|
if not isinstance(other, Model):
|
|
return NotImplemented
|
|
if self._meta.concrete_model != other._meta.concrete_model:
|
|
return False
|
|
my_pk = self.pk
|
|
if my_pk is None:
|
|
return self is other
|
|
return my_pk == other.pk
|
|
|
|
def __hash__(self):
|
|
if self.pk is None:
|
|
raise TypeError("Model instances without primary key value are unhashable")
|
|
return hash(self.pk)
|
|
|
|
def __reduce__(self):
|
|
data = self.__getstate__()
|
|
data[DJANGO_VERSION_PICKLE_KEY] = django.__version__
|
|
class_id = self._meta.app_label, self._meta.object_name
|
|
return model_unpickle, (class_id,), data
|
|
|
|
def __getstate__(self):
|
|
"""Hook to allow choosing the attributes to pickle."""
|
|
state = self.__dict__.copy()
|
|
state["_state"] = copy.copy(state["_state"])
|
|
state["_state"].fields_cache = state["_state"].fields_cache.copy()
|
|
# memoryview cannot be pickled, so cast it to bytes and store
|
|
# separately.
|
|
_memoryview_attrs = []
|
|
for attr, value in state.items():
|
|
if isinstance(value, memoryview):
|
|
_memoryview_attrs.append((attr, bytes(value)))
|
|
if _memoryview_attrs:
|
|
state["_memoryview_attrs"] = _memoryview_attrs
|
|
for attr, value in _memoryview_attrs:
|
|
state.pop(attr)
|
|
return state
|
|
|
|
def __setstate__(self, state):
|
|
pickled_version = state.get(DJANGO_VERSION_PICKLE_KEY)
|
|
if pickled_version:
|
|
if pickled_version != django.__version__:
|
|
warnings.warn(
|
|
"Pickled model instance's Django version %s does not "
|
|
"match the current version %s."
|
|
% (pickled_version, django.__version__),
|
|
RuntimeWarning,
|
|
stacklevel=2,
|
|
)
|
|
else:
|
|
warnings.warn(
|
|
"Pickled model instance's Django version is not specified.",
|
|
RuntimeWarning,
|
|
stacklevel=2,
|
|
)
|
|
if "_memoryview_attrs" in state:
|
|
for attr, value in state.pop("_memoryview_attrs"):
|
|
state[attr] = memoryview(value)
|
|
self.__dict__.update(state)
|
|
|
|
def _get_pk_val(self, meta=None):
|
|
meta = meta or self._meta
|
|
return getattr(self, meta.pk.attname)
|
|
|
|
def _set_pk_val(self, value):
|
|
for parent_link in self._meta.parents.values():
|
|
if parent_link and parent_link != self._meta.pk:
|
|
setattr(self, parent_link.target_field.attname, value)
|
|
return setattr(self, self._meta.pk.attname, value)
|
|
|
|
pk = property(_get_pk_val, _set_pk_val)
|
|
|
|
def get_deferred_fields(self):
|
|
"""
|
|
Return a set containing names of deferred fields for this instance.
|
|
"""
|
|
return {
|
|
f.attname
|
|
for f in self._meta.concrete_fields
|
|
if f.attname not in self.__dict__
|
|
}
|
|
|
|
def refresh_from_db(self, using=None, fields=None):
|
|
"""
|
|
Reload field values from the database.
|
|
|
|
By default, the reloading happens from the database this instance was
|
|
loaded from, or by the read router if this instance wasn't loaded from
|
|
any database. The using parameter will override the default.
|
|
|
|
Fields can be used to specify which fields to reload. The fields
|
|
should be an iterable of field attnames. If fields is None, then
|
|
all non-deferred fields are reloaded.
|
|
|
|
When accessing deferred fields of an instance, the deferred loading
|
|
of the field will call this method.
|
|
"""
|
|
if fields is None:
|
|
self._prefetched_objects_cache = {}
|
|
else:
|
|
prefetched_objects_cache = getattr(self, "_prefetched_objects_cache", ())
|
|
for field in fields:
|
|
if field in prefetched_objects_cache:
|
|
del prefetched_objects_cache[field]
|
|
fields.remove(field)
|
|
if not fields:
|
|
return
|
|
if any(LOOKUP_SEP in f for f in fields):
|
|
raise ValueError(
|
|
'Found "%s" in fields argument. Relations and transforms '
|
|
"are not allowed in fields." % LOOKUP_SEP
|
|
)
|
|
|
|
hints = {"instance": self}
|
|
db_instance_qs = self.__class__._base_manager.db_manager(
|
|
using, hints=hints
|
|
).filter(pk=self.pk)
|
|
|
|
# Use provided fields, if not set then reload all non-deferred fields.
|
|
deferred_fields = self.get_deferred_fields()
|
|
if fields is not None:
|
|
fields = list(fields)
|
|
db_instance_qs = db_instance_qs.only(*fields)
|
|
elif deferred_fields:
|
|
fields = [
|
|
f.attname
|
|
for f in self._meta.concrete_fields
|
|
if f.attname not in deferred_fields
|
|
]
|
|
db_instance_qs = db_instance_qs.only(*fields)
|
|
|
|
db_instance = db_instance_qs.get()
|
|
non_loaded_fields = db_instance.get_deferred_fields()
|
|
for field in self._meta.concrete_fields:
|
|
if field.attname in non_loaded_fields:
|
|
# This field wasn't refreshed - skip ahead.
|
|
continue
|
|
setattr(self, field.attname, getattr(db_instance, field.attname))
|
|
# Clear cached foreign keys.
|
|
if field.is_relation and field.is_cached(self):
|
|
field.delete_cached_value(self)
|
|
|
|
# Clear cached relations.
|
|
for field in self._meta.related_objects:
|
|
if field.is_cached(self):
|
|
field.delete_cached_value(self)
|
|
|
|
self._state.db = db_instance._state.db
|
|
|
|
def serializable_value(self, field_name):
|
|
"""
|
|
Return the value of the field name for this instance. If the field is
|
|
a foreign key, return the id value instead of the object. If there's
|
|
no Field object with this name on the model, return the model
|
|
attribute's value.
|
|
|
|
Used to serialize a field's value (in the serializer, or form output,
|
|
for example). Normally, you would just access the attribute directly
|
|
and not use this method.
|
|
"""
|
|
try:
|
|
field = self._meta.get_field(field_name)
|
|
except FieldDoesNotExist:
|
|
return getattr(self, field_name)
|
|
return getattr(self, field.attname)
|
|
|
|
def save(
|
|
self, force_insert=False, force_update=False, using=None, update_fields=None
|
|
):
|
|
"""
|
|
Save the current instance. Override this in a subclass if you want to
|
|
control the saving process.
|
|
|
|
The 'force_insert' and 'force_update' parameters can be used to insist
|
|
that the "save" must be an SQL insert or update (or equivalent for
|
|
non-SQL backends), respectively. Normally, they should not be set.
|
|
"""
|
|
self._prepare_related_fields_for_save(operation_name="save")
|
|
|
|
using = using or router.db_for_write(self.__class__, instance=self)
|
|
if force_insert and (force_update or update_fields):
|
|
raise ValueError("Cannot force both insert and updating in model saving.")
|
|
|
|
deferred_fields = self.get_deferred_fields()
|
|
if update_fields is not None:
|
|
# If update_fields is empty, skip the save. We do also check for
|
|
# no-op saves later on for inheritance cases. This bailout is
|
|
# still needed for skipping signal sending.
|
|
if not update_fields:
|
|
return
|
|
|
|
update_fields = frozenset(update_fields)
|
|
field_names = self._meta._non_pk_concrete_field_names
|
|
non_model_fields = update_fields.difference(field_names)
|
|
|
|
if non_model_fields:
|
|
raise ValueError(
|
|
"The following fields do not exist in this model, are m2m "
|
|
"fields, or are non-concrete fields: %s"
|
|
% ", ".join(non_model_fields)
|
|
)
|
|
|
|
# If saving to the same database, and this model is deferred, then
|
|
# automatically do an "update_fields" save on the loaded fields.
|
|
elif not force_insert and deferred_fields and using == self._state.db:
|
|
field_names = set()
|
|
for field in self._meta.concrete_fields:
|
|
if not field.primary_key and not hasattr(field, "through"):
|
|
field_names.add(field.attname)
|
|
loaded_fields = field_names.difference(deferred_fields)
|
|
if loaded_fields:
|
|
update_fields = frozenset(loaded_fields)
|
|
|
|
self.save_base(
|
|
using=using,
|
|
force_insert=force_insert,
|
|
force_update=force_update,
|
|
update_fields=update_fields,
|
|
)
|
|
|
|
save.alters_data = True
|
|
|
|
def save_base(
|
|
self,
|
|
raw=False,
|
|
force_insert=False,
|
|
force_update=False,
|
|
using=None,
|
|
update_fields=None,
|
|
):
|
|
"""
|
|
Handle the parts of saving which should be done only once per save,
|
|
yet need to be done in raw saves, too. This includes some sanity
|
|
checks and signal sending.
|
|
|
|
The 'raw' argument is telling save_base not to save any parent
|
|
models and not to do any changes to the values before save. This
|
|
is used by fixture loading.
|
|
"""
|
|
using = using or router.db_for_write(self.__class__, instance=self)
|
|
assert not (force_insert and (force_update or update_fields))
|
|
assert update_fields is None or update_fields
|
|
cls = origin = self.__class__
|
|
# Skip proxies, but keep the origin as the proxy model.
|
|
if cls._meta.proxy:
|
|
cls = cls._meta.concrete_model
|
|
meta = cls._meta
|
|
if not meta.auto_created:
|
|
pre_save.send(
|
|
sender=origin,
|
|
instance=self,
|
|
raw=raw,
|
|
using=using,
|
|
update_fields=update_fields,
|
|
)
|
|
# A transaction isn't needed if one query is issued.
|
|
if meta.parents:
|
|
context_manager = transaction.atomic(using=using, savepoint=False)
|
|
else:
|
|
context_manager = transaction.mark_for_rollback_on_error(using=using)
|
|
with context_manager:
|
|
parent_inserted = False
|
|
if not raw:
|
|
parent_inserted = self._save_parents(cls, using, update_fields)
|
|
updated = self._save_table(
|
|
raw,
|
|
cls,
|
|
force_insert or parent_inserted,
|
|
force_update,
|
|
using,
|
|
update_fields,
|
|
)
|
|
# Store the database on which the object was saved
|
|
self._state.db = using
|
|
# Once saved, this is no longer a to-be-added instance.
|
|
self._state.adding = False
|
|
|
|
# Signal that the save is complete
|
|
if not meta.auto_created:
|
|
post_save.send(
|
|
sender=origin,
|
|
instance=self,
|
|
created=(not updated),
|
|
update_fields=update_fields,
|
|
raw=raw,
|
|
using=using,
|
|
)
|
|
|
|
save_base.alters_data = True
|
|
|
|
def _save_parents(self, cls, using, update_fields):
|
|
"""Save all the parents of cls using values from self."""
|
|
meta = cls._meta
|
|
inserted = False
|
|
for parent, field in meta.parents.items():
|
|
# Make sure the link fields are synced between parent and self.
|
|
if (
|
|
field
|
|
and getattr(self, parent._meta.pk.attname) is None
|
|
and getattr(self, field.attname) is not None
|
|
):
|
|
setattr(self, parent._meta.pk.attname, getattr(self, field.attname))
|
|
parent_inserted = self._save_parents(
|
|
cls=parent, using=using, update_fields=update_fields
|
|
)
|
|
updated = self._save_table(
|
|
cls=parent,
|
|
using=using,
|
|
update_fields=update_fields,
|
|
force_insert=parent_inserted,
|
|
)
|
|
if not updated:
|
|
inserted = True
|
|
# Set the parent's PK value to self.
|
|
if field:
|
|
setattr(self, field.attname, self._get_pk_val(parent._meta))
|
|
# Since we didn't have an instance of the parent handy set
|
|
# attname directly, bypassing the descriptor. Invalidate
|
|
# the related object cache, in case it's been accidentally
|
|
# populated. A fresh instance will be re-built from the
|
|
# database if necessary.
|
|
if field.is_cached(self):
|
|
field.delete_cached_value(self)
|
|
return inserted
|
|
|
|
def _save_table(
|
|
self,
|
|
raw=False,
|
|
cls=None,
|
|
force_insert=False,
|
|
force_update=False,
|
|
using=None,
|
|
update_fields=None,
|
|
):
|
|
"""
|
|
Do the heavy-lifting involved in saving. Update or insert the data
|
|
for a single table.
|
|
"""
|
|
meta = cls._meta
|
|
non_pks = [f for f in meta.local_concrete_fields if not f.primary_key]
|
|
|
|
if update_fields:
|
|
non_pks = [
|
|
f
|
|
for f in non_pks
|
|
if f.name in update_fields or f.attname in update_fields
|
|
]
|
|
|
|
pk_val = self._get_pk_val(meta)
|
|
if pk_val is None:
|
|
pk_val = meta.pk.get_pk_value_on_save(self)
|
|
setattr(self, meta.pk.attname, pk_val)
|
|
pk_set = pk_val is not None
|
|
if not pk_set and (force_update or update_fields):
|
|
raise ValueError("Cannot force an update in save() with no primary key.")
|
|
updated = False
|
|
# Skip an UPDATE when adding an instance and primary key has a default.
|
|
if (
|
|
not raw
|
|
and not force_insert
|
|
and self._state.adding
|
|
and meta.pk.default
|
|
and meta.pk.default is not NOT_PROVIDED
|
|
):
|
|
force_insert = True
|
|
# If possible, try an UPDATE. If that doesn't update anything, do an INSERT.
|
|
if pk_set and not force_insert:
|
|
base_qs = cls._base_manager.using(using)
|
|
values = [
|
|
(
|
|
f,
|
|
None,
|
|
(getattr(self, f.attname) if raw else f.pre_save(self, False)),
|
|
)
|
|
for f in non_pks
|
|
]
|
|
forced_update = update_fields or force_update
|
|
updated = self._do_update(
|
|
base_qs, using, pk_val, values, update_fields, forced_update
|
|
)
|
|
if force_update and not updated:
|
|
raise DatabaseError("Forced update did not affect any rows.")
|
|
if update_fields and not updated:
|
|
raise DatabaseError("Save with update_fields did not affect any rows.")
|
|
if not updated:
|
|
if meta.order_with_respect_to:
|
|
# If this is a model with an order_with_respect_to
|
|
# autopopulate the _order field
|
|
field = meta.order_with_respect_to
|
|
filter_args = field.get_filter_kwargs_for_object(self)
|
|
self._order = (
|
|
cls._base_manager.using(using)
|
|
.filter(**filter_args)
|
|
.aggregate(
|
|
_order__max=Coalesce(
|
|
ExpressionWrapper(
|
|
Max("_order") + Value(1), output_field=IntegerField()
|
|
),
|
|
Value(0),
|
|
),
|
|
)["_order__max"]
|
|
)
|
|
fields = meta.local_concrete_fields
|
|
if not pk_set:
|
|
fields = [f for f in fields if f is not meta.auto_field]
|
|
|
|
returning_fields = meta.db_returning_fields
|
|
results = self._do_insert(
|
|
cls._base_manager, using, fields, returning_fields, raw
|
|
)
|
|
if results:
|
|
for value, field in zip(results[0], returning_fields):
|
|
setattr(self, field.attname, value)
|
|
return updated
|
|
|
|
def _do_update(self, base_qs, using, pk_val, values, update_fields, forced_update):
|
|
"""
|
|
Try to update the model. Return True if the model was updated (if an
|
|
update query was done and a matching row was found in the DB).
|
|
"""
|
|
filtered = base_qs.filter(pk=pk_val)
|
|
if not values:
|
|
# We can end up here when saving a model in inheritance chain where
|
|
# update_fields doesn't target any field in current model. In that
|
|
# case we just say the update succeeded. Another case ending up here
|
|
# is a model with just PK - in that case check that the PK still
|
|
# exists.
|
|
return update_fields is not None or filtered.exists()
|
|
if self._meta.select_on_save and not forced_update:
|
|
return (
|
|
filtered.exists()
|
|
and
|
|
# It may happen that the object is deleted from the DB right after
|
|
# this check, causing the subsequent UPDATE to return zero matching
|
|
# rows. The same result can occur in some rare cases when the
|
|
# database returns zero despite the UPDATE being executed
|
|
# successfully (a row is matched and updated). In order to
|
|
# distinguish these two cases, the object's existence in the
|
|
# database is again checked for if the UPDATE query returns 0.
|
|
(filtered._update(values) > 0 or filtered.exists())
|
|
)
|
|
return filtered._update(values) > 0
|
|
|
|
def _do_insert(self, manager, using, fields, returning_fields, raw):
|
|
"""
|
|
Do an INSERT. If returning_fields is defined then this method should
|
|
return the newly created data for the model.
|
|
"""
|
|
return manager._insert(
|
|
[self],
|
|
fields=fields,
|
|
returning_fields=returning_fields,
|
|
using=using,
|
|
raw=raw,
|
|
)
|
|
|
|
def _prepare_related_fields_for_save(self, operation_name, fields=None):
|
|
# Ensure that a model instance without a PK hasn't been assigned to
|
|
# a ForeignKey, GenericForeignKey or OneToOneField on this model. If
|
|
# the field is nullable, allowing the save would result in silent data
|
|
# loss.
|
|
for field in self._meta.concrete_fields:
|
|
if fields and field not in fields:
|
|
continue
|
|
# If the related field isn't cached, then an instance hasn't been
|
|
# assigned and there's no need to worry about this check.
|
|
if field.is_relation and field.is_cached(self):
|
|
obj = getattr(self, field.name, None)
|
|
if not obj:
|
|
continue
|
|
# A pk may have been assigned manually to a model instance not
|
|
# saved to the database (or auto-generated in a case like
|
|
# UUIDField), but we allow the save to proceed and rely on the
|
|
# database to raise an IntegrityError if applicable. If
|
|
# constraints aren't supported by the database, there's the
|
|
# unavoidable risk of data corruption.
|
|
if obj.pk is None:
|
|
# Remove the object from a related instance cache.
|
|
if not field.remote_field.multiple:
|
|
field.remote_field.delete_cached_value(obj)
|
|
raise ValueError(
|
|
"%s() prohibited to prevent data loss due to unsaved "
|
|
"related object '%s'." % (operation_name, field.name)
|
|
)
|
|
elif getattr(self, field.attname) in field.empty_values:
|
|
# Set related object if it has been saved after an
|
|
# assignment.
|
|
setattr(self, field.name, obj)
|
|
# If the relationship's pk/to_field was changed, clear the
|
|
# cached relationship.
|
|
if getattr(obj, field.target_field.attname) != getattr(
|
|
self, field.attname
|
|
):
|
|
field.delete_cached_value(self)
|
|
# GenericForeignKeys are private.
|
|
for field in self._meta.private_fields:
|
|
if fields and field not in fields:
|
|
continue
|
|
if (
|
|
field.is_relation
|
|
and field.is_cached(self)
|
|
and hasattr(field, "fk_field")
|
|
):
|
|
obj = field.get_cached_value(self, default=None)
|
|
if obj and obj.pk is None:
|
|
raise ValueError(
|
|
f"{operation_name}() prohibited to prevent data loss due to "
|
|
f"unsaved related object '{field.name}'."
|
|
)
|
|
|
|
def delete(self, using=None, keep_parents=False):
|
|
if self.pk is None:
|
|
raise ValueError(
|
|
"%s object can't be deleted because its %s attribute is set "
|
|
"to None." % (self._meta.object_name, self._meta.pk.attname)
|
|
)
|
|
using = using or router.db_for_write(self.__class__, instance=self)
|
|
collector = Collector(using=using, origin=self)
|
|
collector.collect([self], keep_parents=keep_parents)
|
|
return collector.delete()
|
|
|
|
delete.alters_data = True
|
|
|
|
def _get_FIELD_display(self, field):
|
|
value = getattr(self, field.attname)
|
|
choices_dict = dict(make_hashable(field.flatchoices))
|
|
# force_str() to coerce lazy strings.
|
|
return force_str(
|
|
choices_dict.get(make_hashable(value), value), strings_only=True
|
|
)
|
|
|
|
def _get_next_or_previous_by_FIELD(self, field, is_next, **kwargs):
|
|
if not self.pk:
|
|
raise ValueError("get_next/get_previous cannot be used on unsaved objects.")
|
|
op = "gt" if is_next else "lt"
|
|
order = "" if is_next else "-"
|
|
param = getattr(self, field.attname)
|
|
q = Q.create([(field.name, param), (f"pk__{op}", self.pk)], connector=Q.AND)
|
|
q = Q.create([q, (f"{field.name}__{op}", param)], connector=Q.OR)
|
|
qs = (
|
|
self.__class__._default_manager.using(self._state.db)
|
|
.filter(**kwargs)
|
|
.filter(q)
|
|
.order_by("%s%s" % (order, field.name), "%spk" % order)
|
|
)
|
|
try:
|
|
return qs[0]
|
|
except IndexError:
|
|
raise self.DoesNotExist(
|
|
"%s matching query does not exist." % self.__class__._meta.object_name
|
|
)
|
|
|
|
def _get_next_or_previous_in_order(self, is_next):
|
|
cachename = "__%s_order_cache" % is_next
|
|
if not hasattr(self, cachename):
|
|
op = "gt" if is_next else "lt"
|
|
order = "_order" if is_next else "-_order"
|
|
order_field = self._meta.order_with_respect_to
|
|
filter_args = order_field.get_filter_kwargs_for_object(self)
|
|
obj = (
|
|
self.__class__._default_manager.filter(**filter_args)
|
|
.filter(
|
|
**{
|
|
"_order__%s"
|
|
% op: self.__class__._default_manager.values("_order").filter(
|
|
**{self._meta.pk.name: self.pk}
|
|
)
|
|
}
|
|
)
|
|
.order_by(order)[:1]
|
|
.get()
|
|
)
|
|
setattr(self, cachename, obj)
|
|
return getattr(self, cachename)
|
|
|
|
def _get_field_value_map(self, meta, exclude=None):
|
|
if exclude is None:
|
|
exclude = set()
|
|
meta = meta or self._meta
|
|
return {
|
|
field.name: Value(getattr(self, field.attname), field)
|
|
for field in meta.local_concrete_fields
|
|
if field.name not in exclude
|
|
}
|
|
|
|
def prepare_database_save(self, field):
|
|
if self.pk is None:
|
|
raise ValueError(
|
|
"Unsaved model instance %r cannot be used in an ORM query." % self
|
|
)
|
|
return getattr(self, field.remote_field.get_related_field().attname)
|
|
|
|
def clean(self):
|
|
"""
|
|
Hook for doing any extra model-wide validation after clean() has been
|
|
called on every field by self.clean_fields. Any ValidationError raised
|
|
by this method will not be associated with a particular field; it will
|
|
have a special-case association with the field defined by NON_FIELD_ERRORS.
|
|
"""
|
|
pass
|
|
|
|
def validate_unique(self, exclude=None):
|
|
"""
|
|
Check unique constraints on the model and raise ValidationError if any
|
|
failed.
|
|
"""
|
|
unique_checks, date_checks = self._get_unique_checks(exclude=exclude)
|
|
|
|
errors = self._perform_unique_checks(unique_checks)
|
|
date_errors = self._perform_date_checks(date_checks)
|
|
|
|
for k, v in date_errors.items():
|
|
errors.setdefault(k, []).extend(v)
|
|
|
|
if errors:
|
|
raise ValidationError(errors)
|
|
|
|
def _get_unique_checks(self, exclude=None, include_meta_constraints=False):
|
|
"""
|
|
Return a list of checks to perform. Since validate_unique() could be
|
|
called from a ModelForm, some fields may have been excluded; we can't
|
|
perform a unique check on a model that is missing fields involved
|
|
in that check. Fields that did not validate should also be excluded,
|
|
but they need to be passed in via the exclude argument.
|
|
"""
|
|
if exclude is None:
|
|
exclude = set()
|
|
unique_checks = []
|
|
|
|
unique_togethers = [(self.__class__, self._meta.unique_together)]
|
|
constraints = []
|
|
if include_meta_constraints:
|
|
constraints = [(self.__class__, self._meta.total_unique_constraints)]
|
|
for parent_class in self._meta.get_parent_list():
|
|
if parent_class._meta.unique_together:
|
|
unique_togethers.append(
|
|
(parent_class, parent_class._meta.unique_together)
|
|
)
|
|
if include_meta_constraints and parent_class._meta.total_unique_constraints:
|
|
constraints.append(
|
|
(parent_class, parent_class._meta.total_unique_constraints)
|
|
)
|
|
|
|
for model_class, unique_together in unique_togethers:
|
|
for check in unique_together:
|
|
if not any(name in exclude for name in check):
|
|
# Add the check if the field isn't excluded.
|
|
unique_checks.append((model_class, tuple(check)))
|
|
|
|
if include_meta_constraints:
|
|
for model_class, model_constraints in constraints:
|
|
for constraint in model_constraints:
|
|
if not any(name in exclude for name in constraint.fields):
|
|
unique_checks.append((model_class, constraint.fields))
|
|
|
|
# These are checks for the unique_for_<date/year/month>.
|
|
date_checks = []
|
|
|
|
# Gather a list of checks for fields declared as unique and add them to
|
|
# the list of checks.
|
|
|
|
fields_with_class = [(self.__class__, self._meta.local_fields)]
|
|
for parent_class in self._meta.get_parent_list():
|
|
fields_with_class.append((parent_class, parent_class._meta.local_fields))
|
|
|
|
for model_class, fields in fields_with_class:
|
|
for f in fields:
|
|
name = f.name
|
|
if name in exclude:
|
|
continue
|
|
if f.unique:
|
|
unique_checks.append((model_class, (name,)))
|
|
if f.unique_for_date and f.unique_for_date not in exclude:
|
|
date_checks.append((model_class, "date", name, f.unique_for_date))
|
|
if f.unique_for_year and f.unique_for_year not in exclude:
|
|
date_checks.append((model_class, "year", name, f.unique_for_year))
|
|
if f.unique_for_month and f.unique_for_month not in exclude:
|
|
date_checks.append((model_class, "month", name, f.unique_for_month))
|
|
return unique_checks, date_checks
|
|
|
|
def _perform_unique_checks(self, unique_checks):
|
|
errors = {}
|
|
|
|
for model_class, unique_check in unique_checks:
|
|
# Try to look up an existing object with the same values as this
|
|
# object's values for all the unique field.
|
|
|
|
lookup_kwargs = {}
|
|
for field_name in unique_check:
|
|
f = self._meta.get_field(field_name)
|
|
lookup_value = getattr(self, f.attname)
|
|
# TODO: Handle multiple backends with different feature flags.
|
|
if lookup_value is None or (
|
|
lookup_value == ""
|
|
and connection.features.interprets_empty_strings_as_nulls
|
|
):
|
|
# no value, skip the lookup
|
|
continue
|
|
if f.primary_key and not self._state.adding:
|
|
# no need to check for unique primary key when editing
|
|
continue
|
|
lookup_kwargs[str(field_name)] = lookup_value
|
|
|
|
# some fields were skipped, no reason to do the check
|
|
if len(unique_check) != len(lookup_kwargs):
|
|
continue
|
|
|
|
qs = model_class._default_manager.filter(**lookup_kwargs)
|
|
|
|
# Exclude the current object from the query if we are editing an
|
|
# instance (as opposed to creating a new one)
|
|
# Note that we need to use the pk as defined by model_class, not
|
|
# self.pk. These can be different fields because model inheritance
|
|
# allows single model to have effectively multiple primary keys.
|
|
# Refs #17615.
|
|
model_class_pk = self._get_pk_val(model_class._meta)
|
|
if not self._state.adding and model_class_pk is not None:
|
|
qs = qs.exclude(pk=model_class_pk)
|
|
if qs.exists():
|
|
if len(unique_check) == 1:
|
|
key = unique_check[0]
|
|
else:
|
|
key = NON_FIELD_ERRORS
|
|
errors.setdefault(key, []).append(
|
|
self.unique_error_message(model_class, unique_check)
|
|
)
|
|
|
|
return errors
|
|
|
|
def _perform_date_checks(self, date_checks):
|
|
errors = {}
|
|
for model_class, lookup_type, field, unique_for in date_checks:
|
|
lookup_kwargs = {}
|
|
# there's a ticket to add a date lookup, we can remove this special
|
|
# case if that makes it's way in
|
|
date = getattr(self, unique_for)
|
|
if date is None:
|
|
continue
|
|
if lookup_type == "date":
|
|
lookup_kwargs["%s__day" % unique_for] = date.day
|
|
lookup_kwargs["%s__month" % unique_for] = date.month
|
|
lookup_kwargs["%s__year" % unique_for] = date.year
|
|
else:
|
|
lookup_kwargs["%s__%s" % (unique_for, lookup_type)] = getattr(
|
|
date, lookup_type
|
|
)
|
|
lookup_kwargs[field] = getattr(self, field)
|
|
|
|
qs = model_class._default_manager.filter(**lookup_kwargs)
|
|
# Exclude the current object from the query if we are editing an
|
|
# instance (as opposed to creating a new one)
|
|
if not self._state.adding and self.pk is not None:
|
|
qs = qs.exclude(pk=self.pk)
|
|
|
|
if qs.exists():
|
|
errors.setdefault(field, []).append(
|
|
self.date_error_message(lookup_type, field, unique_for)
|
|
)
|
|
return errors
|
|
|
|
def date_error_message(self, lookup_type, field_name, unique_for):
|
|
opts = self._meta
|
|
field = opts.get_field(field_name)
|
|
return ValidationError(
|
|
message=field.error_messages["unique_for_date"],
|
|
code="unique_for_date",
|
|
params={
|
|
"model": self,
|
|
"model_name": capfirst(opts.verbose_name),
|
|
"lookup_type": lookup_type,
|
|
"field": field_name,
|
|
"field_label": capfirst(field.verbose_name),
|
|
"date_field": unique_for,
|
|
"date_field_label": capfirst(opts.get_field(unique_for).verbose_name),
|
|
},
|
|
)
|
|
|
|
def unique_error_message(self, model_class, unique_check):
|
|
opts = model_class._meta
|
|
|
|
params = {
|
|
"model": self,
|
|
"model_class": model_class,
|
|
"model_name": capfirst(opts.verbose_name),
|
|
"unique_check": unique_check,
|
|
}
|
|
|
|
# A unique field
|
|
if len(unique_check) == 1:
|
|
field = opts.get_field(unique_check[0])
|
|
params["field_label"] = capfirst(field.verbose_name)
|
|
return ValidationError(
|
|
message=field.error_messages["unique"],
|
|
code="unique",
|
|
params=params,
|
|
)
|
|
|
|
# unique_together
|
|
else:
|
|
field_labels = [
|
|
capfirst(opts.get_field(f).verbose_name) for f in unique_check
|
|
]
|
|
params["field_labels"] = get_text_list(field_labels, _("and"))
|
|
return ValidationError(
|
|
message=_("%(model_name)s with this %(field_labels)s already exists."),
|
|
code="unique_together",
|
|
params=params,
|
|
)
|
|
|
|
def get_constraints(self):
|
|
constraints = [(self.__class__, self._meta.constraints)]
|
|
for parent_class in self._meta.get_parent_list():
|
|
if parent_class._meta.constraints:
|
|
constraints.append((parent_class, parent_class._meta.constraints))
|
|
return constraints
|
|
|
|
def validate_constraints(self, exclude=None):
|
|
constraints = self.get_constraints()
|
|
using = router.db_for_write(self.__class__, instance=self)
|
|
|
|
errors = {}
|
|
for model_class, model_constraints in constraints:
|
|
for constraint in model_constraints:
|
|
try:
|
|
constraint.validate(model_class, self, exclude=exclude, using=using)
|
|
except ValidationError as e:
|
|
if e.code == "unique" and len(constraint.fields) == 1:
|
|
errors.setdefault(constraint.fields[0], []).append(e)
|
|
else:
|
|
errors = e.update_error_dict(errors)
|
|
if errors:
|
|
raise ValidationError(errors)
|
|
|
|
def full_clean(self, exclude=None, validate_unique=True, validate_constraints=True):
|
|
"""
|
|
Call clean_fields(), clean(), validate_unique(), and
|
|
validate_constraints() on the model. Raise a ValidationError for any
|
|
errors that occur.
|
|
"""
|
|
errors = {}
|
|
if exclude is None:
|
|
exclude = set()
|
|
else:
|
|
exclude = set(exclude)
|
|
|
|
try:
|
|
self.clean_fields(exclude=exclude)
|
|
except ValidationError as e:
|
|
errors = e.update_error_dict(errors)
|
|
|
|
# Form.clean() is run even if other validation fails, so do the
|
|
# same with Model.clean() for consistency.
|
|
try:
|
|
self.clean()
|
|
except ValidationError as e:
|
|
errors = e.update_error_dict(errors)
|
|
|
|
# Run unique checks, but only for fields that passed validation.
|
|
if validate_unique:
|
|
for name in errors:
|
|
if name != NON_FIELD_ERRORS and name not in exclude:
|
|
exclude.add(name)
|
|
try:
|
|
self.validate_unique(exclude=exclude)
|
|
except ValidationError as e:
|
|
errors = e.update_error_dict(errors)
|
|
|
|
# Run constraints checks, but only for fields that passed validation.
|
|
if validate_constraints:
|
|
for name in errors:
|
|
if name != NON_FIELD_ERRORS and name not in exclude:
|
|
exclude.add(name)
|
|
try:
|
|
self.validate_constraints(exclude=exclude)
|
|
except ValidationError as e:
|
|
errors = e.update_error_dict(errors)
|
|
|
|
if errors:
|
|
raise ValidationError(errors)
|
|
|
|
def clean_fields(self, exclude=None):
|
|
"""
|
|
Clean all fields and raise a ValidationError containing a dict
|
|
of all validation errors if any occur.
|
|
"""
|
|
if exclude is None:
|
|
exclude = set()
|
|
|
|
errors = {}
|
|
for f in self._meta.fields:
|
|
if f.name in exclude:
|
|
continue
|
|
# Skip validation for empty fields with blank=True. The developer
|
|
# is responsible for making sure they have a valid value.
|
|
raw_value = getattr(self, f.attname)
|
|
if f.blank and raw_value in f.empty_values:
|
|
continue
|
|
try:
|
|
setattr(self, f.attname, f.clean(raw_value, self))
|
|
except ValidationError as e:
|
|
errors[f.name] = e.error_list
|
|
|
|
if errors:
|
|
raise ValidationError(errors)
|
|
|
|
@classmethod
|
|
def check(cls, **kwargs):
|
|
errors = [
|
|
*cls._check_swappable(),
|
|
*cls._check_model(),
|
|
*cls._check_managers(**kwargs),
|
|
]
|
|
if not cls._meta.swapped:
|
|
databases = kwargs.get("databases") or []
|
|
errors += [
|
|
*cls._check_fields(**kwargs),
|
|
*cls._check_m2m_through_same_relationship(),
|
|
*cls._check_long_column_names(databases),
|
|
]
|
|
clash_errors = (
|
|
*cls._check_id_field(),
|
|
*cls._check_field_name_clashes(),
|
|
*cls._check_model_name_db_lookup_clashes(),
|
|
*cls._check_property_name_related_field_accessor_clashes(),
|
|
*cls._check_single_primary_key(),
|
|
)
|
|
errors.extend(clash_errors)
|
|
# If there are field name clashes, hide consequent column name
|
|
# clashes.
|
|
if not clash_errors:
|
|
errors.extend(cls._check_column_name_clashes())
|
|
errors += [
|
|
*cls._check_index_together(),
|
|
*cls._check_unique_together(),
|
|
*cls._check_indexes(databases),
|
|
*cls._check_ordering(),
|
|
*cls._check_constraints(databases),
|
|
*cls._check_default_pk(),
|
|
]
|
|
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_default_pk(cls):
|
|
if (
|
|
not cls._meta.abstract
|
|
and cls._meta.pk.auto_created
|
|
and
|
|
# Inherited PKs are checked in parents models.
|
|
not (
|
|
isinstance(cls._meta.pk, OneToOneField)
|
|
and cls._meta.pk.remote_field.parent_link
|
|
)
|
|
and not settings.is_overridden("DEFAULT_AUTO_FIELD")
|
|
and cls._meta.app_config
|
|
and not cls._meta.app_config._is_default_auto_field_overridden
|
|
):
|
|
return [
|
|
checks.Warning(
|
|
f"Auto-created primary key used when not defining a "
|
|
f"primary key type, by default "
|
|
f"'{settings.DEFAULT_AUTO_FIELD}'.",
|
|
hint=(
|
|
f"Configure the DEFAULT_AUTO_FIELD setting or the "
|
|
f"{cls._meta.app_config.__class__.__qualname__}."
|
|
f"default_auto_field attribute to point to a subclass "
|
|
f"of AutoField, e.g. 'django.db.models.BigAutoField'."
|
|
),
|
|
obj=cls,
|
|
id="models.W042",
|
|
),
|
|
]
|
|
return []
|
|
|
|
@classmethod
|
|
def _check_swappable(cls):
|
|
"""Check if the swapped model exists."""
|
|
errors = []
|
|
if cls._meta.swapped:
|
|
try:
|
|
apps.get_model(cls._meta.swapped)
|
|
except ValueError:
|
|
errors.append(
|
|
checks.Error(
|
|
"'%s' is not of the form 'app_label.app_name'."
|
|
% cls._meta.swappable,
|
|
id="models.E001",
|
|
)
|
|
)
|
|
except LookupError:
|
|
app_label, model_name = cls._meta.swapped.split(".")
|
|
errors.append(
|
|
checks.Error(
|
|
"'%s' references '%s.%s', which has not been "
|
|
"installed, or is abstract."
|
|
% (cls._meta.swappable, app_label, model_name),
|
|
id="models.E002",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_model(cls):
|
|
errors = []
|
|
if cls._meta.proxy:
|
|
if cls._meta.local_fields or cls._meta.local_many_to_many:
|
|
errors.append(
|
|
checks.Error(
|
|
"Proxy model '%s' contains model fields." % cls.__name__,
|
|
id="models.E017",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_managers(cls, **kwargs):
|
|
"""Perform all manager checks."""
|
|
errors = []
|
|
for manager in cls._meta.managers:
|
|
errors.extend(manager.check(**kwargs))
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_fields(cls, **kwargs):
|
|
"""Perform all field checks."""
|
|
errors = []
|
|
for field in cls._meta.local_fields:
|
|
errors.extend(field.check(**kwargs))
|
|
for field in cls._meta.local_many_to_many:
|
|
errors.extend(field.check(from_model=cls, **kwargs))
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_m2m_through_same_relationship(cls):
|
|
"""Check if no relationship model is used by more than one m2m field."""
|
|
|
|
errors = []
|
|
seen_intermediary_signatures = []
|
|
|
|
fields = cls._meta.local_many_to_many
|
|
|
|
# Skip when the target model wasn't found.
|
|
fields = (f for f in fields if isinstance(f.remote_field.model, ModelBase))
|
|
|
|
# Skip when the relationship model wasn't found.
|
|
fields = (f for f in fields if isinstance(f.remote_field.through, ModelBase))
|
|
|
|
for f in fields:
|
|
signature = (
|
|
f.remote_field.model,
|
|
cls,
|
|
f.remote_field.through,
|
|
f.remote_field.through_fields,
|
|
)
|
|
if signature in seen_intermediary_signatures:
|
|
errors.append(
|
|
checks.Error(
|
|
"The model has two identical many-to-many relations "
|
|
"through the intermediate model '%s'."
|
|
% f.remote_field.through._meta.label,
|
|
obj=cls,
|
|
id="models.E003",
|
|
)
|
|
)
|
|
else:
|
|
seen_intermediary_signatures.append(signature)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_id_field(cls):
|
|
"""Check if `id` field is a primary key."""
|
|
fields = [
|
|
f for f in cls._meta.local_fields if f.name == "id" and f != cls._meta.pk
|
|
]
|
|
# fields is empty or consists of the invalid "id" field
|
|
if fields and not fields[0].primary_key and cls._meta.pk.name == "id":
|
|
return [
|
|
checks.Error(
|
|
"'id' can only be used as a field name if the field also "
|
|
"sets 'primary_key=True'.",
|
|
obj=cls,
|
|
id="models.E004",
|
|
)
|
|
]
|
|
else:
|
|
return []
|
|
|
|
@classmethod
|
|
def _check_field_name_clashes(cls):
|
|
"""Forbid field shadowing in multi-table inheritance."""
|
|
errors = []
|
|
used_fields = {} # name or attname -> field
|
|
|
|
# Check that multi-inheritance doesn't cause field name shadowing.
|
|
for parent in cls._meta.get_parent_list():
|
|
for f in parent._meta.local_fields:
|
|
clash = used_fields.get(f.name) or used_fields.get(f.attname) or None
|
|
if clash:
|
|
errors.append(
|
|
checks.Error(
|
|
"The field '%s' from parent model "
|
|
"'%s' clashes with the field '%s' "
|
|
"from parent model '%s'."
|
|
% (clash.name, clash.model._meta, f.name, f.model._meta),
|
|
obj=cls,
|
|
id="models.E005",
|
|
)
|
|
)
|
|
used_fields[f.name] = f
|
|
used_fields[f.attname] = f
|
|
|
|
# Check that fields defined in the model don't clash with fields from
|
|
# parents, including auto-generated fields like multi-table inheritance
|
|
# child accessors.
|
|
for parent in cls._meta.get_parent_list():
|
|
for f in parent._meta.get_fields():
|
|
if f not in used_fields:
|
|
used_fields[f.name] = f
|
|
|
|
for f in cls._meta.local_fields:
|
|
clash = used_fields.get(f.name) or used_fields.get(f.attname) or None
|
|
# Note that we may detect clash between user-defined non-unique
|
|
# field "id" and automatically added unique field "id", both
|
|
# defined at the same model. This special case is considered in
|
|
# _check_id_field and here we ignore it.
|
|
id_conflict = (
|
|
f.name == "id" and clash and clash.name == "id" and clash.model == cls
|
|
)
|
|
if clash and not id_conflict:
|
|
errors.append(
|
|
checks.Error(
|
|
"The field '%s' clashes with the field '%s' "
|
|
"from model '%s'." % (f.name, clash.name, clash.model._meta),
|
|
obj=f,
|
|
id="models.E006",
|
|
)
|
|
)
|
|
used_fields[f.name] = f
|
|
used_fields[f.attname] = f
|
|
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_column_name_clashes(cls):
|
|
# Store a list of column names which have already been used by other fields.
|
|
used_column_names = []
|
|
errors = []
|
|
|
|
for f in cls._meta.local_fields:
|
|
_, column_name = f.get_attname_column()
|
|
|
|
# Ensure the column name is not already in use.
|
|
if column_name and column_name in used_column_names:
|
|
errors.append(
|
|
checks.Error(
|
|
"Field '%s' has column name '%s' that is used by "
|
|
"another field." % (f.name, column_name),
|
|
hint="Specify a 'db_column' for the field.",
|
|
obj=cls,
|
|
id="models.E007",
|
|
)
|
|
)
|
|
else:
|
|
used_column_names.append(column_name)
|
|
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_model_name_db_lookup_clashes(cls):
|
|
errors = []
|
|
model_name = cls.__name__
|
|
if model_name.startswith("_") or model_name.endswith("_"):
|
|
errors.append(
|
|
checks.Error(
|
|
"The model name '%s' cannot start or end with an underscore "
|
|
"as it collides with the query lookup syntax." % model_name,
|
|
obj=cls,
|
|
id="models.E023",
|
|
)
|
|
)
|
|
elif LOOKUP_SEP in model_name:
|
|
errors.append(
|
|
checks.Error(
|
|
"The model name '%s' cannot contain double underscores as "
|
|
"it collides with the query lookup syntax." % model_name,
|
|
obj=cls,
|
|
id="models.E024",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_property_name_related_field_accessor_clashes(cls):
|
|
errors = []
|
|
property_names = cls._meta._property_names
|
|
related_field_accessors = (
|
|
f.get_attname()
|
|
for f in cls._meta._get_fields(reverse=False)
|
|
if f.is_relation and f.related_model is not None
|
|
)
|
|
for accessor in related_field_accessors:
|
|
if accessor in property_names:
|
|
errors.append(
|
|
checks.Error(
|
|
"The property '%s' clashes with a related field "
|
|
"accessor." % accessor,
|
|
obj=cls,
|
|
id="models.E025",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_single_primary_key(cls):
|
|
errors = []
|
|
if sum(1 for f in cls._meta.local_fields if f.primary_key) > 1:
|
|
errors.append(
|
|
checks.Error(
|
|
"The model cannot have more than one field with "
|
|
"'primary_key=True'.",
|
|
obj=cls,
|
|
id="models.E026",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
# RemovedInDjango51Warning.
|
|
@classmethod
|
|
def _check_index_together(cls):
|
|
"""Check the value of "index_together" option."""
|
|
if not isinstance(cls._meta.index_together, (tuple, list)):
|
|
return [
|
|
checks.Error(
|
|
"'index_together' must be a list or tuple.",
|
|
obj=cls,
|
|
id="models.E008",
|
|
)
|
|
]
|
|
|
|
elif any(
|
|
not isinstance(fields, (tuple, list)) for fields in cls._meta.index_together
|
|
):
|
|
return [
|
|
checks.Error(
|
|
"All 'index_together' elements must be lists or tuples.",
|
|
obj=cls,
|
|
id="models.E009",
|
|
)
|
|
]
|
|
|
|
else:
|
|
errors = []
|
|
for fields in cls._meta.index_together:
|
|
errors.extend(cls._check_local_fields(fields, "index_together"))
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_unique_together(cls):
|
|
"""Check the value of "unique_together" option."""
|
|
if not isinstance(cls._meta.unique_together, (tuple, list)):
|
|
return [
|
|
checks.Error(
|
|
"'unique_together' must be a list or tuple.",
|
|
obj=cls,
|
|
id="models.E010",
|
|
)
|
|
]
|
|
|
|
elif any(
|
|
not isinstance(fields, (tuple, list))
|
|
for fields in cls._meta.unique_together
|
|
):
|
|
return [
|
|
checks.Error(
|
|
"All 'unique_together' elements must be lists or tuples.",
|
|
obj=cls,
|
|
id="models.E011",
|
|
)
|
|
]
|
|
|
|
else:
|
|
errors = []
|
|
for fields in cls._meta.unique_together:
|
|
errors.extend(cls._check_local_fields(fields, "unique_together"))
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_indexes(cls, databases):
|
|
"""Check fields, names, and conditions of indexes."""
|
|
errors = []
|
|
references = set()
|
|
for index in cls._meta.indexes:
|
|
# Index name can't start with an underscore or a number, restricted
|
|
# for cross-database compatibility with Oracle.
|
|
if index.name[0] == "_" or index.name[0].isdigit():
|
|
errors.append(
|
|
checks.Error(
|
|
"The index name '%s' cannot start with an underscore "
|
|
"or a number." % index.name,
|
|
obj=cls,
|
|
id="models.E033",
|
|
),
|
|
)
|
|
if len(index.name) > index.max_name_length:
|
|
errors.append(
|
|
checks.Error(
|
|
"The index name '%s' cannot be longer than %d "
|
|
"characters." % (index.name, index.max_name_length),
|
|
obj=cls,
|
|
id="models.E034",
|
|
),
|
|
)
|
|
if index.contains_expressions:
|
|
for expression in index.expressions:
|
|
references.update(
|
|
ref[0] for ref in cls._get_expr_references(expression)
|
|
)
|
|
for db in databases:
|
|
if not router.allow_migrate_model(db, cls):
|
|
continue
|
|
connection = connections[db]
|
|
if not (
|
|
connection.features.supports_partial_indexes
|
|
or "supports_partial_indexes" in cls._meta.required_db_features
|
|
) and any(index.condition is not None for index in cls._meta.indexes):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support indexes with conditions."
|
|
% connection.display_name,
|
|
hint=(
|
|
"Conditions will be ignored. Silence this warning "
|
|
"if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W037",
|
|
)
|
|
)
|
|
if not (
|
|
connection.features.supports_covering_indexes
|
|
or "supports_covering_indexes" in cls._meta.required_db_features
|
|
) and any(index.include for index in cls._meta.indexes):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support indexes with non-key columns."
|
|
% connection.display_name,
|
|
hint=(
|
|
"Non-key columns will be ignored. Silence this "
|
|
"warning if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W040",
|
|
)
|
|
)
|
|
if not (
|
|
connection.features.supports_expression_indexes
|
|
or "supports_expression_indexes" in cls._meta.required_db_features
|
|
) and any(index.contains_expressions for index in cls._meta.indexes):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support indexes on expressions."
|
|
% connection.display_name,
|
|
hint=(
|
|
"An index won't be created. Silence this warning "
|
|
"if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W043",
|
|
)
|
|
)
|
|
fields = [
|
|
field for index in cls._meta.indexes for field, _ in index.fields_orders
|
|
]
|
|
fields += [include for index in cls._meta.indexes for include in index.include]
|
|
fields += references
|
|
errors.extend(cls._check_local_fields(fields, "indexes"))
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_local_fields(cls, fields, option):
|
|
from django.db import models
|
|
|
|
# In order to avoid hitting the relation tree prematurely, we use our
|
|
# own fields_map instead of using get_field()
|
|
forward_fields_map = {}
|
|
for field in cls._meta._get_fields(reverse=False):
|
|
forward_fields_map[field.name] = field
|
|
if hasattr(field, "attname"):
|
|
forward_fields_map[field.attname] = field
|
|
|
|
errors = []
|
|
for field_name in fields:
|
|
try:
|
|
field = forward_fields_map[field_name]
|
|
except KeyError:
|
|
errors.append(
|
|
checks.Error(
|
|
"'%s' refers to the nonexistent field '%s'."
|
|
% (
|
|
option,
|
|
field_name,
|
|
),
|
|
obj=cls,
|
|
id="models.E012",
|
|
)
|
|
)
|
|
else:
|
|
if isinstance(field.remote_field, models.ManyToManyRel):
|
|
errors.append(
|
|
checks.Error(
|
|
"'%s' refers to a ManyToManyField '%s', but "
|
|
"ManyToManyFields are not permitted in '%s'."
|
|
% (
|
|
option,
|
|
field_name,
|
|
option,
|
|
),
|
|
obj=cls,
|
|
id="models.E013",
|
|
)
|
|
)
|
|
elif field not in cls._meta.local_fields:
|
|
errors.append(
|
|
checks.Error(
|
|
"'%s' refers to field '%s' which is not local to model "
|
|
"'%s'." % (option, field_name, cls._meta.object_name),
|
|
hint="This issue may be caused by multi-table inheritance.",
|
|
obj=cls,
|
|
id="models.E016",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_ordering(cls):
|
|
"""
|
|
Check "ordering" option -- is it a list of strings and do all fields
|
|
exist?
|
|
"""
|
|
if cls._meta._ordering_clash:
|
|
return [
|
|
checks.Error(
|
|
"'ordering' and 'order_with_respect_to' cannot be used together.",
|
|
obj=cls,
|
|
id="models.E021",
|
|
),
|
|
]
|
|
|
|
if cls._meta.order_with_respect_to or not cls._meta.ordering:
|
|
return []
|
|
|
|
if not isinstance(cls._meta.ordering, (list, tuple)):
|
|
return [
|
|
checks.Error(
|
|
"'ordering' must be a tuple or list (even if you want to order by "
|
|
"only one field).",
|
|
obj=cls,
|
|
id="models.E014",
|
|
)
|
|
]
|
|
|
|
errors = []
|
|
fields = cls._meta.ordering
|
|
|
|
# Skip expressions and '?' fields.
|
|
fields = (f for f in fields if isinstance(f, str) and f != "?")
|
|
|
|
# Convert "-field" to "field".
|
|
fields = ((f[1:] if f.startswith("-") else f) for f in fields)
|
|
|
|
# Separate related fields and non-related fields.
|
|
_fields = []
|
|
related_fields = []
|
|
for f in fields:
|
|
if LOOKUP_SEP in f:
|
|
related_fields.append(f)
|
|
else:
|
|
_fields.append(f)
|
|
fields = _fields
|
|
|
|
# Check related fields.
|
|
for field in related_fields:
|
|
_cls = cls
|
|
fld = None
|
|
for part in field.split(LOOKUP_SEP):
|
|
try:
|
|
# pk is an alias that won't be found by opts.get_field.
|
|
if part == "pk":
|
|
fld = _cls._meta.pk
|
|
else:
|
|
fld = _cls._meta.get_field(part)
|
|
if fld.is_relation:
|
|
_cls = fld.path_infos[-1].to_opts.model
|
|
else:
|
|
_cls = None
|
|
except (FieldDoesNotExist, AttributeError):
|
|
if fld is None or (
|
|
fld.get_transform(part) is None and fld.get_lookup(part) is None
|
|
):
|
|
errors.append(
|
|
checks.Error(
|
|
"'ordering' refers to the nonexistent field, "
|
|
"related field, or lookup '%s'." % field,
|
|
obj=cls,
|
|
id="models.E015",
|
|
)
|
|
)
|
|
|
|
# Skip ordering on pk. This is always a valid order_by field
|
|
# but is an alias and therefore won't be found by opts.get_field.
|
|
fields = {f for f in fields if f != "pk"}
|
|
|
|
# Check for invalid or nonexistent fields in ordering.
|
|
invalid_fields = []
|
|
|
|
# Any field name that is not present in field_names does not exist.
|
|
# Also, ordering by m2m fields is not allowed.
|
|
opts = cls._meta
|
|
valid_fields = set(
|
|
chain.from_iterable(
|
|
(f.name, f.attname)
|
|
if not (f.auto_created and not f.concrete)
|
|
else (f.field.related_query_name(),)
|
|
for f in chain(opts.fields, opts.related_objects)
|
|
)
|
|
)
|
|
|
|
invalid_fields.extend(fields - valid_fields)
|
|
|
|
for invalid_field in invalid_fields:
|
|
errors.append(
|
|
checks.Error(
|
|
"'ordering' refers to the nonexistent field, related "
|
|
"field, or lookup '%s'." % invalid_field,
|
|
obj=cls,
|
|
id="models.E015",
|
|
)
|
|
)
|
|
return errors
|
|
|
|
@classmethod
|
|
def _check_long_column_names(cls, databases):
|
|
"""
|
|
Check that any auto-generated column names are shorter than the limits
|
|
for each database in which the model will be created.
|
|
"""
|
|
if not databases:
|
|
return []
|
|
errors = []
|
|
allowed_len = None
|
|
db_alias = None
|
|
|
|
# Find the minimum max allowed length among all specified db_aliases.
|
|
for db in databases:
|
|
# skip databases where the model won't be created
|
|
if not router.allow_migrate_model(db, cls):
|
|
continue
|
|
connection = connections[db]
|
|
max_name_length = connection.ops.max_name_length()
|
|
if max_name_length is None or connection.features.truncates_names:
|
|
continue
|
|
else:
|
|
if allowed_len is None:
|
|
allowed_len = max_name_length
|
|
db_alias = db
|
|
elif max_name_length < allowed_len:
|
|
allowed_len = max_name_length
|
|
db_alias = db
|
|
|
|
if allowed_len is None:
|
|
return errors
|
|
|
|
for f in cls._meta.local_fields:
|
|
_, column_name = f.get_attname_column()
|
|
|
|
# Check if auto-generated name for the field is too long
|
|
# for the database.
|
|
if (
|
|
f.db_column is None
|
|
and column_name is not None
|
|
and len(column_name) > allowed_len
|
|
):
|
|
errors.append(
|
|
checks.Error(
|
|
'Autogenerated column name too long for field "%s". '
|
|
'Maximum length is "%s" for database "%s".'
|
|
% (column_name, allowed_len, db_alias),
|
|
hint="Set the column name manually using 'db_column'.",
|
|
obj=cls,
|
|
id="models.E018",
|
|
)
|
|
)
|
|
|
|
for f in cls._meta.local_many_to_many:
|
|
# Skip nonexistent models.
|
|
if isinstance(f.remote_field.through, str):
|
|
continue
|
|
|
|
# Check if auto-generated name for the M2M field is too long
|
|
# for the database.
|
|
for m2m in f.remote_field.through._meta.local_fields:
|
|
_, rel_name = m2m.get_attname_column()
|
|
if (
|
|
m2m.db_column is None
|
|
and rel_name is not None
|
|
and len(rel_name) > allowed_len
|
|
):
|
|
errors.append(
|
|
checks.Error(
|
|
"Autogenerated column name too long for M2M field "
|
|
'"%s". Maximum length is "%s" for database "%s".'
|
|
% (rel_name, allowed_len, db_alias),
|
|
hint=(
|
|
"Use 'through' to create a separate model for "
|
|
"M2M and then set column_name using 'db_column'."
|
|
),
|
|
obj=cls,
|
|
id="models.E019",
|
|
)
|
|
)
|
|
|
|
return errors
|
|
|
|
@classmethod
|
|
def _get_expr_references(cls, expr):
|
|
if isinstance(expr, Q):
|
|
for child in expr.children:
|
|
if isinstance(child, tuple):
|
|
lookup, value = child
|
|
yield tuple(lookup.split(LOOKUP_SEP))
|
|
yield from cls._get_expr_references(value)
|
|
else:
|
|
yield from cls._get_expr_references(child)
|
|
elif isinstance(expr, F):
|
|
yield tuple(expr.name.split(LOOKUP_SEP))
|
|
elif hasattr(expr, "get_source_expressions"):
|
|
for src_expr in expr.get_source_expressions():
|
|
yield from cls._get_expr_references(src_expr)
|
|
|
|
@classmethod
|
|
def _check_constraints(cls, databases):
|
|
errors = []
|
|
for db in databases:
|
|
if not router.allow_migrate_model(db, cls):
|
|
continue
|
|
connection = connections[db]
|
|
if not (
|
|
connection.features.supports_table_check_constraints
|
|
or "supports_table_check_constraints" in cls._meta.required_db_features
|
|
) and any(
|
|
isinstance(constraint, CheckConstraint)
|
|
for constraint in cls._meta.constraints
|
|
):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support check constraints."
|
|
% connection.display_name,
|
|
hint=(
|
|
"A constraint won't be created. Silence this "
|
|
"warning if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W027",
|
|
)
|
|
)
|
|
if not (
|
|
connection.features.supports_partial_indexes
|
|
or "supports_partial_indexes" in cls._meta.required_db_features
|
|
) and any(
|
|
isinstance(constraint, UniqueConstraint)
|
|
and constraint.condition is not None
|
|
for constraint in cls._meta.constraints
|
|
):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support unique constraints with "
|
|
"conditions." % connection.display_name,
|
|
hint=(
|
|
"A constraint won't be created. Silence this "
|
|
"warning if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W036",
|
|
)
|
|
)
|
|
if not (
|
|
connection.features.supports_deferrable_unique_constraints
|
|
or "supports_deferrable_unique_constraints"
|
|
in cls._meta.required_db_features
|
|
) and any(
|
|
isinstance(constraint, UniqueConstraint)
|
|
and constraint.deferrable is not None
|
|
for constraint in cls._meta.constraints
|
|
):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support deferrable unique constraints."
|
|
% connection.display_name,
|
|
hint=(
|
|
"A constraint won't be created. Silence this "
|
|
"warning if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W038",
|
|
)
|
|
)
|
|
if not (
|
|
connection.features.supports_covering_indexes
|
|
or "supports_covering_indexes" in cls._meta.required_db_features
|
|
) and any(
|
|
isinstance(constraint, UniqueConstraint) and constraint.include
|
|
for constraint in cls._meta.constraints
|
|
):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support unique constraints with non-key "
|
|
"columns." % connection.display_name,
|
|
hint=(
|
|
"A constraint won't be created. Silence this "
|
|
"warning if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W039",
|
|
)
|
|
)
|
|
if not (
|
|
connection.features.supports_expression_indexes
|
|
or "supports_expression_indexes" in cls._meta.required_db_features
|
|
) and any(
|
|
isinstance(constraint, UniqueConstraint)
|
|
and constraint.contains_expressions
|
|
for constraint in cls._meta.constraints
|
|
):
|
|
errors.append(
|
|
checks.Warning(
|
|
"%s does not support unique constraints on "
|
|
"expressions." % connection.display_name,
|
|
hint=(
|
|
"A constraint won't be created. Silence this "
|
|
"warning if you don't care about it."
|
|
),
|
|
obj=cls,
|
|
id="models.W044",
|
|
)
|
|
)
|
|
fields = set(
|
|
chain.from_iterable(
|
|
(*constraint.fields, *constraint.include)
|
|
for constraint in cls._meta.constraints
|
|
if isinstance(constraint, UniqueConstraint)
|
|
)
|
|
)
|
|
references = set()
|
|
for constraint in cls._meta.constraints:
|
|
if isinstance(constraint, UniqueConstraint):
|
|
if (
|
|
connection.features.supports_partial_indexes
|
|
or "supports_partial_indexes"
|
|
not in cls._meta.required_db_features
|
|
) and isinstance(constraint.condition, Q):
|
|
references.update(
|
|
cls._get_expr_references(constraint.condition)
|
|
)
|
|
if (
|
|
connection.features.supports_expression_indexes
|
|
or "supports_expression_indexes"
|
|
not in cls._meta.required_db_features
|
|
) and constraint.contains_expressions:
|
|
for expression in constraint.expressions:
|
|
references.update(cls._get_expr_references(expression))
|
|
elif isinstance(constraint, CheckConstraint):
|
|
if (
|
|
connection.features.supports_table_check_constraints
|
|
or "supports_table_check_constraints"
|
|
not in cls._meta.required_db_features
|
|
):
|
|
if isinstance(constraint.check, Q):
|
|
references.update(
|
|
cls._get_expr_references(constraint.check)
|
|
)
|
|
if any(
|
|
isinstance(expr, RawSQL)
|
|
for expr in constraint.check.flatten()
|
|
):
|
|
errors.append(
|
|
checks.Warning(
|
|
f"Check constraint {constraint.name!r} contains "
|
|
f"RawSQL() expression and won't be validated "
|
|
f"during the model full_clean().",
|
|
hint=(
|
|
"Silence this warning if you don't care about "
|
|
"it."
|
|
),
|
|
obj=cls,
|
|
id="models.W045",
|
|
),
|
|
)
|
|
for field_name, *lookups in references:
|
|
# pk is an alias that won't be found by opts.get_field.
|
|
if field_name != "pk":
|
|
fields.add(field_name)
|
|
if not lookups:
|
|
# If it has no lookups it cannot result in a JOIN.
|
|
continue
|
|
try:
|
|
if field_name == "pk":
|
|
field = cls._meta.pk
|
|
else:
|
|
field = cls._meta.get_field(field_name)
|
|
if not field.is_relation or field.many_to_many or field.one_to_many:
|
|
continue
|
|
except FieldDoesNotExist:
|
|
continue
|
|
# JOIN must happen at the first lookup.
|
|
first_lookup = lookups[0]
|
|
if (
|
|
hasattr(field, "get_transform")
|
|
and hasattr(field, "get_lookup")
|
|
and field.get_transform(first_lookup) is None
|
|
and field.get_lookup(first_lookup) is None
|
|
):
|
|
errors.append(
|
|
checks.Error(
|
|
"'constraints' refers to the joined field '%s'."
|
|
% LOOKUP_SEP.join([field_name] + lookups),
|
|
obj=cls,
|
|
id="models.E041",
|
|
)
|
|
)
|
|
errors.extend(cls._check_local_fields(fields, "constraints"))
|
|
return errors
|
|
|
|
|
|
############################################
|
|
# HELPER FUNCTIONS (CURRIED MODEL METHODS) #
|
|
############################################
|
|
|
|
# ORDERING METHODS #########################
|
|
|
|
|
|
def method_set_order(self, ordered_obj, id_list, using=None):
|
|
order_wrt = ordered_obj._meta.order_with_respect_to
|
|
filter_args = order_wrt.get_forward_related_filter(self)
|
|
ordered_obj.objects.db_manager(using).filter(**filter_args).bulk_update(
|
|
[ordered_obj(pk=pk, _order=order) for order, pk in enumerate(id_list)],
|
|
["_order"],
|
|
)
|
|
|
|
|
|
def method_get_order(self, ordered_obj):
|
|
order_wrt = ordered_obj._meta.order_with_respect_to
|
|
filter_args = order_wrt.get_forward_related_filter(self)
|
|
pk_name = ordered_obj._meta.pk.name
|
|
return ordered_obj.objects.filter(**filter_args).values_list(pk_name, flat=True)
|
|
|
|
|
|
def make_foreign_order_accessors(model, related_model):
|
|
setattr(
|
|
related_model,
|
|
"get_%s_order" % model.__name__.lower(),
|
|
partialmethod(method_get_order, model),
|
|
)
|
|
setattr(
|
|
related_model,
|
|
"set_%s_order" % model.__name__.lower(),
|
|
partialmethod(method_set_order, model),
|
|
)
|
|
|
|
|
|
########
|
|
# MISC #
|
|
########
|
|
|
|
|
|
def model_unpickle(model_id):
|
|
"""Used to unpickle Model subclasses with deferred fields."""
|
|
if isinstance(model_id, tuple):
|
|
model = apps.get_model(*model_id)
|
|
else:
|
|
# Backwards compat - the model was cached directly in earlier versions.
|
|
model = model_id
|
|
return model.__new__(model)
|
|
|
|
|
|
model_unpickle.__safe_for_unpickle__ = True
|