mysteriendrama/lib/python3.11/site-packages/django/db/models/fields/related_lookups.py

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2023-07-22 12:04:19 +02:00
import warnings
from django.db.models.lookups import (
Exact,
GreaterThan,
GreaterThanOrEqual,
In,
IsNull,
LessThan,
LessThanOrEqual,
)
from django.utils.deprecation import RemovedInDjango50Warning
class MultiColSource:
contains_aggregate = False
contains_over_clause = False
def __init__(self, alias, targets, sources, field):
self.targets, self.sources, self.field, self.alias = (
targets,
sources,
field,
alias,
)
self.output_field = self.field
def __repr__(self):
return "{}({}, {})".format(self.__class__.__name__, self.alias, self.field)
def relabeled_clone(self, relabels):
return self.__class__(
relabels.get(self.alias, self.alias), self.targets, self.sources, self.field
)
def get_lookup(self, lookup):
return self.output_field.get_lookup(lookup)
def resolve_expression(self, *args, **kwargs):
return self
def get_normalized_value(value, lhs):
from django.db.models import Model
if isinstance(value, Model):
if value.pk is None:
# When the deprecation ends, replace with:
# raise ValueError(
# "Model instances passed to related filters must be saved."
# )
warnings.warn(
"Passing unsaved model instances to related filters is deprecated.",
RemovedInDjango50Warning,
)
value_list = []
sources = lhs.output_field.path_infos[-1].target_fields
for source in sources:
while not isinstance(value, source.model) and source.remote_field:
source = source.remote_field.model._meta.get_field(
source.remote_field.field_name
)
try:
value_list.append(getattr(value, source.attname))
except AttributeError:
# A case like Restaurant.objects.filter(place=restaurant_instance),
# where place is a OneToOneField and the primary key of Restaurant.
return (value.pk,)
return tuple(value_list)
if not isinstance(value, tuple):
return (value,)
return value
class RelatedIn(In):
def get_prep_lookup(self):
if not isinstance(self.lhs, MultiColSource):
if self.rhs_is_direct_value():
# If we get here, we are dealing with single-column relations.
self.rhs = [get_normalized_value(val, self.lhs)[0] for val in self.rhs]
# We need to run the related field's get_prep_value(). Consider
# case ForeignKey to IntegerField given value 'abc'. The
# ForeignKey itself doesn't have validation for non-integers,
# so we must run validation using the target field.
if hasattr(self.lhs.output_field, "path_infos"):
# Run the target field's get_prep_value. We can safely
# assume there is only one as we don't get to the direct
# value branch otherwise.
target_field = self.lhs.output_field.path_infos[-1].target_fields[
-1
]
self.rhs = [target_field.get_prep_value(v) for v in self.rhs]
elif not getattr(self.rhs, "has_select_fields", True) and not getattr(
self.lhs.field.target_field, "primary_key", False
):
if (
getattr(self.lhs.output_field, "primary_key", False)
and self.lhs.output_field.model == self.rhs.model
):
# A case like
# Restaurant.objects.filter(place__in=restaurant_qs), where
# place is a OneToOneField and the primary key of
# Restaurant.
target_field = self.lhs.field.name
else:
target_field = self.lhs.field.target_field.name
self.rhs.set_values([target_field])
return super().get_prep_lookup()
def as_sql(self, compiler, connection):
if isinstance(self.lhs, MultiColSource):
# For multicolumn lookups we need to build a multicolumn where clause.
# This clause is either a SubqueryConstraint (for values that need
# to be compiled to SQL) or an OR-combined list of
# (col1 = val1 AND col2 = val2 AND ...) clauses.
from django.db.models.sql.where import (
AND,
OR,
SubqueryConstraint,
WhereNode,
)
root_constraint = WhereNode(connector=OR)
if self.rhs_is_direct_value():
values = [get_normalized_value(value, self.lhs) for value in self.rhs]
for value in values:
value_constraint = WhereNode()
for source, target, val in zip(
self.lhs.sources, self.lhs.targets, value
):
lookup_class = target.get_lookup("exact")
lookup = lookup_class(
target.get_col(self.lhs.alias, source), val
)
value_constraint.add(lookup, AND)
root_constraint.add(value_constraint, OR)
else:
root_constraint.add(
SubqueryConstraint(
self.lhs.alias,
[target.column for target in self.lhs.targets],
[source.name for source in self.lhs.sources],
self.rhs,
),
AND,
)
return root_constraint.as_sql(compiler, connection)
return super().as_sql(compiler, connection)
class RelatedLookupMixin:
def get_prep_lookup(self):
if not isinstance(self.lhs, MultiColSource) and not hasattr(
self.rhs, "resolve_expression"
):
# If we get here, we are dealing with single-column relations.
self.rhs = get_normalized_value(self.rhs, self.lhs)[0]
# We need to run the related field's get_prep_value(). Consider case
# ForeignKey to IntegerField given value 'abc'. The ForeignKey itself
# doesn't have validation for non-integers, so we must run validation
# using the target field.
if self.prepare_rhs and hasattr(self.lhs.output_field, "path_infos"):
# Get the target field. We can safely assume there is only one
# as we don't get to the direct value branch otherwise.
target_field = self.lhs.output_field.path_infos[-1].target_fields[-1]
self.rhs = target_field.get_prep_value(self.rhs)
return super().get_prep_lookup()
def as_sql(self, compiler, connection):
if isinstance(self.lhs, MultiColSource):
assert self.rhs_is_direct_value()
self.rhs = get_normalized_value(self.rhs, self.lhs)
from django.db.models.sql.where import AND, WhereNode
root_constraint = WhereNode()
for target, source, val in zip(
self.lhs.targets, self.lhs.sources, self.rhs
):
lookup_class = target.get_lookup(self.lookup_name)
root_constraint.add(
lookup_class(target.get_col(self.lhs.alias, source), val), AND
)
return root_constraint.as_sql(compiler, connection)
return super().as_sql(compiler, connection)
class RelatedExact(RelatedLookupMixin, Exact):
pass
class RelatedLessThan(RelatedLookupMixin, LessThan):
pass
class RelatedGreaterThan(RelatedLookupMixin, GreaterThan):
pass
class RelatedGreaterThanOrEqual(RelatedLookupMixin, GreaterThanOrEqual):
pass
class RelatedLessThanOrEqual(RelatedLookupMixin, LessThanOrEqual):
pass
class RelatedIsNull(RelatedLookupMixin, IsNull):
pass