Django_Basic_Manufacturing_3/venv/Lib/site-packages/modeltranslation/manager.py
2025-08-22 17:05:22 +07:00

639 lines
25 KiB
Python

"""
The idea of MultilingualManager is taken from
django-linguo by Zach Mathew
https://github.com/zmathew/django-linguo
"""
from __future__ import annotations
import itertools
from functools import reduce
from typing import Any, Literal, TypeVar, cast, overload
from collections.abc import Container, Iterator, Sequence, Iterable
from django.contrib.admin.utils import get_model_from_relation
from django.core.exceptions import FieldDoesNotExist
from django.db import models
from django.db.backends.utils import CursorWrapper
from django.db.models import Field, Model, F
from django.db.models.expressions import Col
from django.db.models.functions import Concat, ConcatPair
from django.db.models.lookups import Lookup
from django.db.models.query import QuerySet, ValuesIterable
from django.db.models.utils import create_namedtuple_class
from django.utils.tree import Node
from modeltranslation._typing import Self, AutoPopulate
from modeltranslation.fields import TranslationField
from modeltranslation.thread_context import auto_populate_mode
from modeltranslation.utils import (
auto_populate,
build_localized_fieldname,
get_language,
resolution_order,
)
_C2F_CACHE: dict[tuple[type[Model], str], Field] = {}
_F2TM_CACHE: dict[type[Model], dict[str, type[Model]]] = {}
def get_translatable_fields_for_model(model: type[Model]) -> list[str] | None:
from modeltranslation.translator import NotRegistered, translator
try:
return translator.get_options_for_model(model).get_field_names()
except NotRegistered:
return None
def rewrite_lookup_key(model: type[Model], lookup_key: str) -> str:
try:
pieces = lookup_key.split("__", 1)
original_key = pieces[0]
translatable_fields = get_translatable_fields_for_model(model)
if translatable_fields is not None:
# If we are doing a lookup on a translatable field,
# we want to rewrite it to the actual field name
# For example, we want to rewrite "name__startswith" to "name_fr__startswith"
if pieces[0] in translatable_fields:
pieces[0] = build_localized_fieldname(pieces[0], get_language())
if len(pieces) > 1:
# Check if we are doing a lookup to a related trans model
fields_to_trans_models = get_fields_to_translatable_models(model)
# Check ``original key``, as pieces[0] may have been already rewritten.
if original_key in fields_to_trans_models:
transmodel = fields_to_trans_models[original_key]
pieces[1] = rewrite_lookup_key(transmodel, pieces[1])
return "__".join(pieces)
except AttributeError:
return lookup_key
def append_fallback(model: type[Model], fields: Sequence[str]) -> tuple[set[str], set[str]]:
"""
If translated field is encountered, add also all its fallback fields.
Returns tuple: (set_of_new_fields_to_use, set_of_translated_field_names)
"""
fields_set = set(fields)
trans: set[str] = set()
from modeltranslation.translator import translator
opts = translator.get_options_for_model(model)
for key, _ in opts.all_fields.items():
if key in fields_set:
langs = resolution_order(get_language(), getattr(model, key).fallback_languages)
fields_set = fields_set.union(build_localized_fieldname(key, lang) for lang in langs)
fields_set.remove(key)
trans.add(key)
return fields_set, trans
def append_translated(model: type[Model], fields: Iterable[str]) -> set[str]:
"If translated field is encountered, add also all its translation fields."
fields_set = set(fields)
from modeltranslation.translator import translator
opts = translator.get_options_for_model(model)
for key, translated in opts.all_fields.items():
if key in fields_set:
fields_set = fields_set.union(f.name for f in translated)
return fields_set
def append_lookup_key(model: type[Model], lookup_key: str) -> set[str]:
"Transform spanned__lookup__key into all possible translation versions, on all levels"
pieces = lookup_key.split("__", 1)
fields = append_translated(model, (pieces[0],))
if len(pieces) > 1:
# Check if we are doing a lookup to a related trans model
fields_to_trans_models = get_fields_to_translatable_models(model)
if pieces[0] in fields_to_trans_models:
transmodel = fields_to_trans_models[pieces[0]]
rest = append_lookup_key(transmodel, pieces[1])
fields = {"__".join(pr) for pr in itertools.product(fields, rest)}
else:
fields = {"%s__%s" % (f, pieces[1]) for f in fields}
return fields
def append_lookup_keys(model: type[Model], fields: Sequence[str]) -> set[str]:
new_fields = []
for field in fields:
try:
new_field: Container[str] = append_lookup_key(model, field)
except AttributeError:
new_field = (field,)
new_fields.append(new_field)
return reduce(set.union, new_fields, set()) # type: ignore[arg-type]
def rewrite_order_lookup_key(model: type[Model], lookup_key: str) -> str:
try:
if lookup_key.startswith("-"):
return "-" + rewrite_lookup_key(model, lookup_key[1:])
else:
return rewrite_lookup_key(model, lookup_key)
except AttributeError:
return lookup_key
def get_fields_to_translatable_models(model: type[Model]) -> dict[str, type[Model]]:
if model in _F2TM_CACHE:
return _F2TM_CACHE[model]
results: list[tuple[str, type[Model]]] = []
for f in model._meta.get_fields():
if f.is_relation and f.related_model:
# The new get_field() will find GenericForeignKey relations.
# In that case the 'related_model' attribute is set to None
# so it is necessary to check for this value before trying to
# get translatable fields.
related_model = get_model_from_relation(f) # type: ignore[arg-type]
if get_translatable_fields_for_model(related_model) is not None:
results.append((f.name, related_model))
_F2TM_CACHE[model] = dict(results)
return _F2TM_CACHE[model]
def get_field_by_colum_name(model: type[Model], col: str) -> Field:
# First, try field with the column name
try:
field = cast(Field, model._meta.get_field(col))
if field.column == col:
return field
except FieldDoesNotExist:
pass
field = _C2F_CACHE.get((model, col), None) # type: ignore[arg-type]
if field:
return field
# D'oh, need to search through all of them.
for field in model._meta.fields:
if field.column == col:
_C2F_CACHE[(model, col)] = field
return field
assert False, "No field found for column %s" % col
_T = TypeVar("_T", bound=Model, covariant=True)
class MultilingualQuerySet(QuerySet[_T]):
def __init__(self, *args: Any, **kwargs: Any) -> None:
super().__init__(*args, **kwargs)
self._post_init()
def _post_init(self) -> None:
self._rewrite = True
self._populate = None
if self.model and self.query.default_ordering and (not self.query.order_by):
if self.model._meta.ordering:
# If we have default ordering specified on the model, set it now so that
# it can be rewritten. Otherwise sql.compiler will grab it directly from _meta
ordering = []
for key in self.model._meta.ordering:
ordering.append(rewrite_order_lookup_key(self.model, key))
self.query.add_ordering(*ordering)
def __reduce__(self):
return multilingual_queryset_factory, (self.__class__.__bases__[0],), self.__getstate__()
def _clone(self) -> Self:
return self.__clone()
def __clone(self, **kwargs: Any) -> Self:
# This method is private, so outside code can use default _clone without `kwargs`,
# and we're here can use private version with `kwargs`.
# Refs: https://github.com/deschler/django-modeltranslation/issues/483
kwargs.setdefault("_rewrite", self._rewrite)
kwargs.setdefault("_populate", self._populate)
if hasattr(self, "translation_fields"):
kwargs.setdefault("translation_fields", self.translation_fields)
if hasattr(self, "original_fields"):
kwargs.setdefault("original_fields", self.original_fields)
cloned = super()._clone()
cloned.__dict__.update(kwargs)
return cloned
def rewrite(self, mode: bool = True) -> Self:
return self.__clone(_rewrite=mode)
def populate(self, mode: AutoPopulate = "all") -> Self:
"""
Overrides the translation fields population mode for this query set.
"""
return self.__clone(_populate=mode)
def _rewrite_applied_operations(self) -> None:
"""
Rewrite fields in already applied filters/ordering.
Useful when converting any QuerySet into MultilingualQuerySet.
"""
self._rewrite_where(self.query.where)
self._rewrite_order()
self._rewrite_select_related()
# This method was not present in django-linguo
def select_related(self, *fields: Any, **kwargs: Any) -> Self:
if not self._rewrite:
return super().select_related(*fields, **kwargs)
# TO CONSIDER: whether this should rewrite only current language, or all languages?
# fk -> [fk, fk_en] (with en=active) VS fk -> [fk, fk_en, fk_de, fk_fr ...] (for all langs)
# new_args = append_lookup_keys(self.model, fields)
new_args: list[str | None] = []
for key in fields:
if key is None:
new_args.append(None)
else:
new_args.append(rewrite_lookup_key(self.model, key))
return super().select_related(*new_args, **kwargs)
# This method was not present in django-linguo
def _rewrite_col(self, col: Col) -> None:
"""Django >= 1.7 column name rewriting"""
if isinstance(col, Col):
new_name = rewrite_lookup_key(self.model, col.target.name)
if col.target.name != new_name:
new_field = self.model._meta.get_field(new_name)
if col.target is col.source:
col.source = new_field
col.target = new_field
elif hasattr(col, "col"):
self._rewrite_col(col.col)
elif hasattr(col, "lhs"):
self._rewrite_col(col.lhs)
def _rewrite_where(self, q: Lookup | Node) -> None:
"""
Rewrite field names inside WHERE tree.
"""
if isinstance(q, Lookup):
self._rewrite_col(q.lhs)
if isinstance(q, Node):
for child in q.children:
self._rewrite_where(child)
def _rewrite_order(self) -> None:
self.query.order_by = [
rewrite_order_lookup_key(self.model, field_name) for field_name in self.query.order_by
]
def _rewrite_select_related(self) -> None:
if isinstance(self.query.select_related, dict):
new = {}
for field_name, value in self.query.select_related.items():
new[rewrite_order_lookup_key(self.model, field_name)] = value
self.query.select_related = new
# This method was not present in django-linguo
def _rewrite_q(self, q: Node | tuple[str, Any]) -> Any:
"""Rewrite field names inside Q call."""
if isinstance(q, tuple) and len(q) == 2:
return rewrite_lookup_key(self.model, q[0]), q[1]
if isinstance(q, Node):
q.children = list(map(self._rewrite_q, q.children))
return q
# This method was not present in django-linguo
def _rewrite_f(self, q: models.F | Node) -> models.F | Node:
"""
Rewrite field names inside F call.
"""
if isinstance(q, models.F):
q.name = rewrite_lookup_key(self.model, q.name)
return q
if isinstance(q, Node):
q.children = list(map(self._rewrite_f, q.children))
# Django >= 1.8
if hasattr(q, "lhs"):
q.lhs = self._rewrite_f(q.lhs)
if hasattr(q, "rhs"):
q.rhs = self._rewrite_f(q.rhs)
return q
def _rewrite_filter_or_exclude(self, args: Any, kwargs: Any) -> tuple[Any, Any]:
if not self._rewrite:
return args, kwargs
args = tuple(map(self._rewrite_q, args))
for key, val in list(kwargs.items()):
new_key = rewrite_lookup_key(self.model, key)
del kwargs[key]
kwargs[new_key] = self._rewrite_f(val)
return args, kwargs
def _filter_or_exclude(self, negate: bool, args: Any, kwargs: Any) -> Self:
args, kwargs = self._rewrite_filter_or_exclude(args, kwargs)
return super()._filter_or_exclude(negate, args, kwargs)
def _get_original_fields(self) -> list[str]:
source = (
self.model._meta.concrete_fields
if hasattr(self.model._meta, "concrete_fields")
else self.model._meta.fields
)
return [f.attname for f in source if not isinstance(f, TranslationField)]
def order_by(self, *field_names: Any) -> Self:
"""
Change translatable field names in an ``order_by`` argument
to translation fields for the current language.
"""
if not self._rewrite:
return super().order_by(*field_names)
new_args = []
for key in field_names:
new_args.append(rewrite_order_lookup_key(self.model, key))
return super().order_by(*new_args)
def distinct(self, *field_names: Any) -> Self:
"""
Change translatable field names in an ``distinct`` argument
to translation fields for the current language.
"""
if not self._rewrite:
return super().distinct(*field_names)
new_args = []
for key in field_names:
new_args.append(rewrite_order_lookup_key(self.model, key))
return super().distinct(*new_args)
def update(self, **kwargs: Any) -> int:
if not self._rewrite:
return super().update(**kwargs)
for key, val in list(kwargs.items()):
new_key = rewrite_lookup_key(self.model, key)
del kwargs[key]
kwargs[new_key] = self._rewrite_f(val)
return super().update(**kwargs)
update.alters_data = True
def _update(self, values: list[tuple[Field, type[Model] | None, Any]]) -> CursorWrapper:
"""
This method is called in .save() method to update an existing record.
Here we force to update translation fields as well if the original
field only is passed in `save()` in argument `update_fields`.
"""
# TODO: Should the original field (field without lang code suffix) be updated
# when only the default translation field (`field_<DEFAULT_LANG_CODE>`) is passed in `update_fields`?
# Currently, we don't synchronize values of the original and default translation fields in that case.
field_names_to_update = {field.name for field, *_ in values}
translation_values: list[tuple[Field, type[Model] | None, Any]] = []
for field, model, value in values:
translation_field_name = rewrite_lookup_key(self.model, field.name)
if translation_field_name not in field_names_to_update:
translatable_field = cast(Field, self.model._meta.get_field(translation_field_name))
translation_values.append((translatable_field, model, value))
values += translation_values
return super()._update(values)
# This method was not present in django-linguo
@property
def _populate_mode(self) -> AutoPopulate:
# Populate can be set using a global setting or a manager method.
if self._populate is None:
return auto_populate_mode()
return self._populate
# This method was not present in django-linguo
def create(self, **kwargs: Any) -> _T:
"""
Allows to override population mode with a ``populate`` method.
"""
with auto_populate(self._populate_mode):
return super().create(**kwargs)
# This method was not present in django-linguo
def get_or_create(self, *args: Any, **kwargs: Any) -> tuple[_T, bool]:
"""
Allows to override population mode with a ``populate`` method.
"""
with auto_populate(self._populate_mode):
return super().get_or_create(*args, **kwargs)
# This method was not present in django-linguo
def defer(self, *fields: Any) -> Self:
fields = append_lookup_keys(self.model, fields) # type: ignore[assignment]
return super().defer(*fields)
# This method was not present in django-linguo
def only(self, *fields: Any) -> Self:
fields = append_lookup_keys(self.model, fields) # type: ignore[assignment]
return super().only(*fields)
# This method was not present in django-linguo
def raw_values(self, *fields: str, **expressions: Any) -> Self:
return super().values(*fields, **expressions)
def _values(self, *original: str, **kwargs: Any) -> Self:
selects_all = kwargs.pop("selects_all", False)
if not kwargs.pop("prepare", False):
return super()._values(*original, **kwargs)
new_fields, translation_fields = append_fallback(self.model, original)
annotation_keys = set(self.query.annotation_select.keys()) if selects_all else set()
new_fields.update(annotation_keys)
clone = super()._values(*list(new_fields), **kwargs)
clone.original_fields = tuple(original)
clone.translation_fields = translation_fields
return clone
# This method was not present in django-linguo
def values(self, *fields: str, **expressions: Any) -> Self:
if not self._rewrite:
return super().values(*fields, **expressions)
selects_all = not fields
if not fields:
# Emulate original queryset behaviour: get all fields that are not translation fields
fields = self._get_original_fields() # type: ignore[assignment]
fields += tuple(expressions)
clone = self._values(*fields, prepare=True, selects_all=selects_all, **expressions)
clone._iterable_class = FallbackValuesIterable
return clone
# This method was not present in django-linguo
def values_list(self, *fields: str, flat: bool = False, named: bool = False) -> Self:
if not self._rewrite:
return super().values_list(*fields, flat=flat, named=named)
if flat and named:
raise TypeError("'flat' and 'named' can't be used together.")
if flat and len(fields) > 1:
raise TypeError(
"'flat' is not valid when values_list is called with more than one field."
)
selects_all = not fields
if not fields:
# Emulate original queryset behaviour: get all fields that are not translation fields
fields = self._get_original_fields() # type: ignore[assignment]
field_names = {f for f in fields if not hasattr(f, "resolve_expression")}
_fields = []
expressions = {}
counter = 1
for field in fields:
if hasattr(field, "resolve_expression"):
field_id_prefix = getattr(field, "default_alias", field.__class__.__name__.lower())
while True:
field_id = field_id_prefix + str(counter)
counter += 1
if field_id not in field_names:
break
expressions[field_id] = field
_fields.append(field_id)
else:
_fields.append(field)
clone = self._values(*_fields, prepare=True, selects_all=selects_all, **expressions)
clone._iterable_class = (
FallbackNamedValuesListIterable
if named
else FallbackFlatValuesListIterable
if flat
else FallbackValuesListIterable
)
return clone
# This method was not present in django-linguo
def dates(self, field_name: str, *args: Any, **kwargs: Any) -> Self:
if not self._rewrite:
return super().dates(field_name, *args, **kwargs)
new_key = rewrite_lookup_key(self.model, field_name)
return super().dates(new_key, *args, **kwargs)
def _rewrite_concat(self, concat: Concat | ConcatPair):
new_source_expressions = []
for exp in concat.source_expressions:
if isinstance(exp, (Concat, ConcatPair)):
exp = self._rewrite_concat(exp)
if isinstance(exp, F):
exp = self._rewrite_f(exp)
new_source_expressions.append(exp)
concat.set_source_expressions(new_source_expressions)
return concat
def annotate(self, *args: Any, **kwargs: Any) -> Self:
if not self._rewrite:
return super().annotate(*args, **kwargs)
for key, val in list(kwargs.items()):
if isinstance(val, models.F):
kwargs[key] = self._rewrite_f(val)
if isinstance(val, Concat):
kwargs[key] = self._rewrite_concat(val)
return super().annotate(*args, **kwargs)
class FallbackValuesIterable(ValuesIterable):
queryset: MultilingualQuerySet[Model]
class X:
# This stupid class is needed as object use __slots__ and has no __dict__.
pass
def __iter__(self) -> Iterator[dict[str, Any]]:
instance = self.X()
fields = self.queryset.original_fields
fields += tuple(f for f in self.queryset.query.annotation_select if f not in fields)
for row in super().__iter__():
instance.__dict__.update(row)
for key in self.queryset.translation_fields:
row[key] = getattr(self.queryset.model, key).__get__(instance, None)
# Restore original ordering.
yield {k: row[k] for k in fields}
class FallbackValuesListIterable(FallbackValuesIterable):
def __iter__(self) -> Iterator[tuple[Any, ...]]:
for row in super().__iter__():
yield tuple(row.values())
class FallbackNamedValuesListIterable(FallbackValuesIterable):
def __iter__(self) -> Iterator[tuple[Any, ...]]:
for row in super().__iter__():
names, values = row.keys(), row.values()
tuple_class = create_namedtuple_class(*names)
new = tuple.__new__
yield new(tuple_class, values)
class FallbackFlatValuesListIterable(FallbackValuesListIterable):
def __iter__(self) -> Iterator[Any]:
for row in super().__iter__():
yield row[0]
@overload
def multilingual_queryset_factory(
old_cls: type[Any], instantiate: Literal[False]
) -> type[MultilingualQuerySet]: ...
@overload
def multilingual_queryset_factory(
old_cls: type[Any], instantiate: Literal[True] = ...
) -> MultilingualQuerySet: ...
def multilingual_queryset_factory(
old_cls: type[Any], instantiate: bool = True
) -> type[MultilingualQuerySet] | MultilingualQuerySet:
if old_cls == models.query.QuerySet:
NewClass = MultilingualQuerySet
else:
class NewClass(old_cls, MultilingualQuerySet): # type: ignore[no-redef]
pass
NewClass.__name__ = "Multilingual%s" % old_cls.__name__
return NewClass() if instantiate else NewClass
class MultilingualQuerysetManager(models.Manager[_T]):
"""
This class gets hooked in MRO just before plain Manager, so that every call to
get_queryset returns MultilingualQuerySet.
"""
def get_queryset(self) -> MultilingualQuerySet[_T]:
qs = super().get_queryset()
return self._patch_queryset(qs)
def _patch_queryset(self, qs: QuerySet[_T]) -> MultilingualQuerySet[_T]:
qs.__class__ = multilingual_queryset_factory(qs.__class__, instantiate=False)
qs = cast(MultilingualQuerySet[_T], qs)
qs._post_init()
qs._rewrite_applied_operations()
return qs
class MultilingualManager(MultilingualQuerysetManager[_T]):
def rewrite(self, *args: Any, **kwargs: Any):
return self.get_queryset().rewrite(*args, **kwargs)
def populate(self, *args: Any, **kwargs: Any):
return self.get_queryset().populate(*args, **kwargs)
def raw_values(self, *args: Any, **kwargs: Any):
return self.get_queryset().raw_values(*args, **kwargs)
def get_queryset(self) -> MultilingualQuerySet[_T]:
"""
This method is repeated because some managers that don't use super() or alter queryset class
may return queryset that is not subclass of MultilingualQuerySet.
"""
qs = super().get_queryset()
if isinstance(qs, MultilingualQuerySet):
# Is already patched by MultilingualQuerysetManager - in most of the cases
# when custom managers use super() properly in get_queryset.
return qs
return self._patch_queryset(qs)