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pyint-87acf0d168ba-I13

Lower every eligible synchronous for loop to a while loop

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Posnett00–1; higher is more readable
Dorn00–1; higher is more readable
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Source code

import copy import operator import warnings from contextlib import nullcontext from functools import partial, reduce from itertools import chain, islice from weakref import ref as weak_ref from asgiref.sync import sync_to_async import django from django.conf import settings from django.core import exceptions from django.db import ( DJANGO_VERSION_PICKLE_KEY, IntegrityError, NotSupportedError, connections, router, transaction, ) from django.db.models import AutoField, DateField, DateTimeField, Field, Max, sql from django.db.models.constants import LOOKUP_SEP, OnConflict from django.db.models.deletion import Collector from django.db.models.expressions import ( Case, Col, ColPairs, DatabaseDefault, F, OrderBy, Value, When, ) from django.db.models.fetch_modes import FETCH_ONE from django.db.models.functions import Cast, Trunc from django.db.models.query_utils import PROHIBITED_FILTER_KWARGS, FilteredRelation, Q from django.db.models.sql.constants import GET_ITERATOR_CHUNK_SIZE, ROW_COUNT from django.db.models.utils import ( AltersData, create_namedtuple_class, resolve_callables, ) from django.utils import timezone from django.utils.deprecation import ( RemovedInDjango70Warning, RemovedInDjango71Warning, warn_about_external_use, ) from django.utils.functional import cached_property from django.utils.inspect import func_accepts_kwargs, func_supports_parameter from django.utils.warnings import django_file_prefixes class QuerySet(AltersData): """Represent a lazy database lookup for a set of objects.""" def __init__(self, model=None, query=None, using=None, hints=None): self.model = model self._db = using self._hints = hints or {} self._query = query or sql.Query(self.model) self._result_cache = None self._sticky_filter = False self._for_write = False self._prefetch_related_lookups = () self._prefetch_done = False self._known_related_objects = {} # {rel_field: {pk: rel_obj}} self._iterable_class = ModelIterable self._fetch_mode = DEFAULT_FETCH_MODE self._fields = None self._defer_next_filter = False self._deferred_filter = None self._cloning_enabled = True @property def query(self): if self._deferred_filter: negate, args, kwargs = self._deferred_filter self._filter_or_exclude_inplace(negate, args, kwargs) self._deferred_filter = None return self._query @query.setter def query(self, value): if value.values_select: self._iterable_class = ValuesIterable self._query = value def as_manager(cls): # Address the circular dependency between `Queryset` and `Manager`. from django.db.models.manager import Manager manager = Manager.from_queryset(cls)() manager._built_with_as_manager = True return manager as_manager.queryset_only = True as_manager = classmethod(as_manager) ######################## # PYTHON MAGIC METHODS # ######################## def __deepcopy__(self, memo): """Don't populate the QuerySet's cache.""" obj = self.__class__() loopIterator = __import__("builtins").iter(self.__dict__.items()) while True: try: k, v = __import__("builtins").next(loopIterator) except __import__("builtins").StopIteration: break if k == "_result_cache": obj.__dict__[k] = None else: obj.__dict__[k] = copy.deepcopy(v, memo) return obj def __getstate__(self): # Force the cache to be fully populated. self._fetch_all() return {**self.__dict__, DJANGO_VERSION_PICKLE_KEY: django.__version__} def __setstate__(self, state): pickled_version = state.get(DJANGO_VERSION_PICKLE_KEY) if pickled_version: if pickled_version != django.__version__: warnings.warn( "Pickled queryset instance's Django version %s does not " "match the current version %s." % (pickled_version, django.__version__), RuntimeWarning, stacklevel=2, ) else: warnings.warn( "Pickled queryset instance's Django version is not specified.", RuntimeWarning, stacklevel=2, ) self.__dict__.update(state) def __repr__(self): data = list(self[: REPR_OUTPUT_SIZE + 1]) if len(data) > REPR_OUTPUT_SIZE: data[-1] = "...(remaining elements truncated)..." return "<%s %r>" % (self.__class__.__name__, data) def __len__(self): self._fetch_all() return len(self._result_cache) def __iter__(self): """ The queryset iterator protocol uses three nested iterators in the default case: 1. sql.compiler.execute_sql() - Returns 100 rows at time (constants.GET_ITERATOR_CHUNK_SIZE) using cursor.fetchmany(). This part is responsible for doing some column masking, and returning the rows in chunks. 2. sql.compiler.results_iter() - Returns one row at time. At this point the rows are still just tuples. In some cases the return values are converted to Python values at this location. 3. self.iterator() - Responsible for turning the rows into model objects. """ self._fetch_all() return iter(self._result_cache) def __aiter__(self): # Remember, __aiter__ itself is synchronous, it's the thing it returns # that is async! async def generator(): await sync_to_async(self._fetch_all)() loopIteratorA = __import__("builtins").iter(self._result_cache) while True: try: item = __import__("builtins").next(loopIteratorA) except __import__("builtins").StopIteration: break yield item return generator() def __bool__(self): self._fetch_all() return bool(self._result_cache) def __getitem__(self, k): """Retrieve an item or slice from the set of results.""" if not isinstance(k, (int, slice)): raise TypeError( "QuerySet indices must be integers or slices, not %s." % type(k).__name__ ) if (isinstance(k, int) and k < 0) or ( isinstance(k, slice) and ( (k.start is not None and k.start < 0) or (k.stop is not None and k.stop < 0) ) ): raise ValueError("Negative indexing is not supported.") if self._result_cache is not None: return self._result_cache[k] if isinstance(k, slice): qs = self._chain() if k.start is not None: start = int(k.start) else: start = None if k.stop is not None: stop = int(k.stop) else: stop = None qs.query.set_limits(start, stop) return list(qs)[:: k.step] if k.step else qs qs = self._chain() qs.query.set_limits(k, k + 1) qs._fetch_all() return qs._result_cache[0] def __class_getitem__(cls, *args, **kwargs): return cls def __and__(self, other): self._check_operator_queryset(other, "&") self._merge_sanity_check(other) if isinstance(other, EmptyQuerySet): return other if isinstance(self, EmptyQuerySet): return self combined = self._chain() combined._merge_known_related_objects(other) combined.query.combine(other.query, sql.AND) return combined def __or__(self, other): self._check_operator_queryset(other, "|") self._merge_sanity_check(other) if isinstance(self, EmptyQuerySet): return other if isinstance(other, EmptyQuerySet): return self query = ( self if self.query.can_filter() else self.model._base_manager.filter(pk__in=self.values("pk")) ) combined = query._chain() combined._merge_known_related_objects(other) if not other.query.can_filter(): other = other.model._base_manager.filter(pk__in=other.values("pk")) combined.query.combine(other.query, sql.OR) return combined def __xor__(self, other): self._check_operator_queryset(other, "^") self._merge_sanity_check(other) if isinstance(self, EmptyQuerySet): return other if isinstance(other, EmptyQuerySet): return self query = ( self if self.query.can_filter() else self.model._base_manager.filter(pk__in=self.values("pk")) ) combined = query._chain() combined._merge_known_related_objects(other) if not other.query.can_filter(): other = other.model._base_manager.filter(pk__in=other.values("pk")) combined.query.combine(other.query, sql.XOR) return combined #################################### # METHODS THAT DO DATABASE QUERIES # #################################### def _iterator(self, use_chunked_fetch, chunk_size): iterable = self._iterable_class( self, chunked_fetch=use_chunked_fetch, chunk_size=chunk_size or 2000, ) if not self._prefetch_related_lookups or chunk_size is None: yield from iterable return iterator = iter(iterable) while results := list(islice(iterator, chunk_size)): prefetch_related_objects(results, *self._prefetch_related_lookups) yield from results def iterator(self, chunk_size=None): """ An iterator over the results from applying this QuerySet to the database. chunk_size must be provided for QuerySets that prefetch related objects. Otherwise, a default chunk_size of 2000 is supplied. """ if chunk_size is None: if self._prefetch_related_lookups: raise ValueError( "chunk_size must be provided when using QuerySet.iterator() after " "prefetch_related()." ) elif chunk_size <= 0: raise ValueError("Chunk size must be strictly positive.") use_chunked_fetch = not connections[self.db].settings_dict.get( "DISABLE_SERVER_SIDE_CURSORS" ) return self._iterator(use_chunked_fetch, chunk_size) async def aiterator(self, chunk_size=None): """ An asynchronous iterator over the results from applying this QuerySet to the database. """ if chunk_size is None: if self._prefetch_related_lookups: # RemovedInDjango71Warning: Replace the warning with: # raise ValueError( # "chunk_size must be provided when using " # "QuerySet.aiterator() after prefetch_related()." # ) warnings.warn( "Using QuerySet.aiterator() after prefetch_related() without " "providing a chunk_size is deprecated and will raise a " "ValueError in Django 7.1.", category=RemovedInDjango71Warning, skip_file_prefixes=django_file_prefixes(), ) # RemovedInDjango71Warning: When the deprecation ends, remove. chunk_size = 2000 elif chunk_size <= 0: raise ValueError("Chunk size must be strictly positive.") use_chunked_fetch = not connections[self.db].settings_dict.get( "DISABLE_SERVER_SIDE_CURSORS" ) iterable = self._iterable_class( self, chunked_fetch=use_chunked_fetch, chunk_size=chunk_size or 2000, ) if self._prefetch_related_lookups: results = [] async for item in iterable: results.append(item) if len(results) >= chunk_size: await aprefetch_related_objects( results, *self._prefetch_related_lookups ) loopIteratorB = __import__("builtins").iter(results) while True: try: result = __import__("builtins").next(loopIteratorB) except __import__("builtins").StopIteration: break yield result results.clear() if results: await aprefetch_related_objects( results, *self._prefetch_related_lookups ) loopIteratorC = __import__("builtins").iter(results) while True: try: result = __import__("builtins").next(loopIteratorC) except __import__("builtins").StopIteration: break yield result else: async for item in iterable: yield item def aggregate(self, *args, **kwargs): """ Return a dictionary containing the calculations (aggregation) over the current queryset. If args is present the expression is passed as a kwarg using the Aggregate object's default alias. """ if self.query.distinct_fields: raise NotImplementedError("aggregate() + distinct(fields) not implemented.") self._validate_values_are_expressions( (*args, *kwargs.values()), method_name="aggregate" ) for arg in args: # The default_alias property raises TypeError if default_alias # can't be set automatically or AttributeError if it isn't an # attribute. try: arg.default_alias except (AttributeError, TypeError): raise TypeError("Complex aggregates require an alias") kwargs[arg.default_alias] = arg return self.query.chain().get_aggregation(self.db, kwargs) async def aaggregate(self, *args, **kwargs): return await sync_to_async(self.aggregate)(*args, **kwargs) def count(self): """ Perform a SELECT COUNT() and return the number of records as an integer. If the QuerySet is already fully cached, return the length of the cached results set to avoid multiple SELECT COUNT(*) calls. """ if self._result_cache is not None: return len(self._result_cache) return self.query.get_count(using=self.db) async def acount(self): return await sync_to_async(self.count)() def get(self, *args, **kwargs): """ Perform the query and return a single object matching the given keyword arguments. """ if self.query.combinator and (args or kwargs): raise NotSupportedError( "Calling QuerySet.get(...) with filters after %s() is not " "supported." % self.query.combinator ) clone = self._chain() if self.query.combinator else self.filter(*args, **kwargs) if self.query.can_filter() and not self.query.distinct_fields: clone = clone.order_by() limit = None if ( not clone.query.select_for_update or connections[clone.db].features.supports_select_for_update_with_limit ): limit = MAX_GET_RESULTS clone.query.set_limits(high=limit) num = len(clone) if num == 1: return clone._result_cache[0] if not num: raise self.model.DoesNotExist( "%s matching query does not exist." % self.model._meta.object_name ) raise self.model.MultipleObjectsReturned( "get() returned more than one %s -- it returned %s!" % ( self.model._meta.object_name, num if not limit or num < limit else "more than %s" % (limit - 1), ) ) async def aget(self, *args, **kwargs): return await sync_to_async(self.get)(*args, **kwargs) def create(self, **kwargs): """ Create a new object with the given kwargs, saving it to the database and returning the created object. """ reverse_one_to_one_fields = frozenset(kwargs).intersection( self.model._meta._reverse_one_to_one_field_names ) if reverse_one_to_one_fields: raise ValueError( "The following fields do not exist in this model: %s" % ", ".join(reverse_one_to_one_fields) ) obj = self.model(**kwargs) self._for_write = True obj.save(force_insert=True, using=self.db) obj._state.fetch_mode = self._fetch_mode return obj create.alters_data = True async def acreate(self, **kwargs): return await sync_to_async(self.create)(**kwargs) acreate.alters_data = True def _prepare_for_bulk_create(self, objs): objs_with_pk, objs_without_pk = [], [] loopIteratorD = __import__("builtins").iter(objs) while True: try: obj = __import__("builtins").next(loopIteratorD) except __import__("builtins").StopIteration: break obj._prepare_related_fields_for_save(operation_name="bulk_create") if isinstance(obj.pk, DatabaseDefault): objs_without_pk.append(obj) elif obj._is_pk_set(): objs_with_pk.append(obj) else: obj.pk = obj._meta.pk.get_pk_value_on_save(obj) if obj._is_pk_set(): objs_with_pk.append(obj) else: objs_without_pk.append(obj) return objs_with_pk, objs_without_pk def _check_bulk_create_options( self, ignore_conflicts, update_conflicts, update_fields, unique_fields ): if ignore_conflicts and update_conflicts: raise ValueError( "ignore_conflicts and update_conflicts are mutually exclusive." ) db_features = connections[self.db].features if ignore_conflicts: if not db_features.supports_ignore_conflicts: raise NotSupportedError( "This database backend does not support ignoring conflicts." ) return OnConflict.IGNORE elif update_conflicts: if not db_features.supports_update_conflicts: raise NotSupportedError( "This database backend does not support updating conflicts." ) if not update_fields: raise ValueError( "Fields that will be updated when a row insertion fails " "on conflicts must be provided." ) if unique_fields and not db_features.supports_update_conflicts_with_target: raise NotSupportedError( "This database backend does not support updating " "conflicts with specifying unique fields that can trigger " "the upsert." ) if not unique_fields and db_features.supports_update_conflicts_with_target: raise ValueError( "Unique fields that can trigger the upsert must be provided." ) # Updating primary keys and non-concrete fields is forbidden. if any(not f.concrete for f in update_fields): raise ValueError( "bulk_create() can only be used with concrete fields in " "update_fields." ) if any(f in self.model._meta.pk_fields for f in update_fields): raise ValueError( "bulk_create() cannot be used with primary keys in " "update_fields." ) if unique_fields: if any(not f.concrete for f in unique_fields): raise ValueError( "bulk_create() can only be used with concrete fields " "in unique_fields." ) return OnConflict.UPDATE return None def bulk_create( self, objs, batch_size=None, ignore_conflicts=False, update_conflicts=False, update_fields=None, unique_fields=None, ): """ Insert each of the instances into the database. Do *not* call save() on each of the instances, do not send any pre/post_save signals, and do not set the primary key attribute if it is an autoincrement field (except if features.can_return_rows_from_bulk_insert=True). Multi-table models are not supported. """ # When you bulk insert you don't get the primary keys back (if it's an # autoincrement, except if can_return_rows_from_bulk_insert=True), so # you can't insert into the child tables which references this. There # are two workarounds: # 1) This could be implemented if you didn't have an autoincrement pk # 2) You could do it by doing O(n) normal inserts into the parent # tables to get the primary keys back and then doing a single bulk # insert into the childmost table. # We currently set the primary keys on the objects when using # PostgreSQL via the RETURNING ID clause. It should be possible for # Oracle as well, but the semantics for extracting the primary keys is # trickier so it's not done yet. if batch_size is not None and batch_size <= 0: raise ValueError("Batch size must be a positive integer.") # Check that the parents share the same concrete model with the our # model to detect the inheritance pattern ConcreteGrandParent -> # MultiTableParent -> ProxyChild. Simply checking # self.model._meta.proxy would not identify that case as involving # multiple tables. loopIteratorE = __import__("builtins").iter(self.model._meta.all_parents) while True: try: parent = __import__("builtins").next(loopIteratorE) except __import__("builtins").StopIteration: break if parent._meta.concrete_model is not self.model._meta.concrete_model: raise ValueError("Can't bulk create a multi-table inherited model") if not objs: return objs opts = self.model._meta if unique_fields: # Primary key is allowed in unique_fields. unique_fields = [ self.model._meta.get_field(opts.pk.name if name == "pk" else name) for name in unique_fields ] if update_fields: update_fields = [self.model._meta.get_field(name) for name in update_fields] on_conflict = self._check_bulk_create_options( ignore_conflicts, update_conflicts, update_fields, unique_fields, ) self._for_write = True fields = [f for f in opts.concrete_fields if not f.generated] objs = list(objs) objs_with_pk, objs_without_pk = self._prepare_for_bulk_create(objs) if objs_with_pk and objs_without_pk: context = transaction.atomic(using=self.db, savepoint=False) else: context = nullcontext() with context: self._handle_order_with_respect_to(objs) if objs_with_pk: returned_columns = self._batched_insert( objs_with_pk, fields, batch_size, on_conflict=on_conflict, update_fields=update_fields, unique_fields=unique_fields, ) loopIteratorAD = __import__("builtins").iter(zip(objs_with_pk, returned_columns)) while True: try: obj_with_pk, results = __import__("builtins").next(loopIteratorAD) except __import__("builtins").StopIteration: break loopIteratorF = __import__("builtins").iter(zip(results, opts.db_returning_fields)) while True: try: result, field = __import__("builtins").next(loopIteratorF) except __import__("builtins").StopIteration: break setattr(obj_with_pk, field.attname, result) loopIteratorG = __import__("builtins").iter(objs_with_pk) while True: try: obj_with_pk = __import__("builtins").next(loopIteratorG) except __import__("builtins").StopIteration: break obj_with_pk._state.adding = False obj_with_pk._state.db = self.db if objs_without_pk: fields = [f for f in fields if not isinstance(f, AutoField)] returned_columns = self._batched_insert( objs_without_pk, fields, batch_size, on_conflict=on_conflict, update_fields=update_fields, unique_fields=unique_fields, ) connection = connections[self.db] if ( connection.features.can_return_rows_from_bulk_insert and on_conflict is None ): assert len(returned_columns) == len(objs_without_pk) loopIteratorAE = __import__("builtins").iter(zip(objs_without_pk, returned_columns)) while True: try: obj_without_pk, results = __import__("builtins").next(loopIteratorAE) except __import__("builtins").StopIteration: break loopIteratorH = __import__("builtins").iter(zip(results, opts.db_returning_fields)) while True: try: result, field = __import__("builtins").next(loopIteratorH) except __import__("builtins").StopIteration: break setattr(obj_without_pk, field.attname, result) obj_without_pk._state.adding = False obj_without_pk._state.db = self.db return objs def _handle_order_with_respect_to(self, objs): if objs and (order_wrt := self.model._meta.order_with_respect_to): get_filter_kwargs_for_object = order_wrt.get_filter_kwargs_for_object attnames = list(get_filter_kwargs_for_object(objs[0])) group_keys = set() obj_groups = [] loopIteratorI = __import__("builtins").iter(objs) while True: try: obj = __import__("builtins").next(loopIteratorI) except __import__("builtins").StopIteration: break group_key = tuple(get_filter_kwargs_for_object(obj).values()) group_keys.add(group_key) obj_groups.append((obj, group_key)) filters = [ Q.create(list(zip(attnames, group_key))) for group_key in group_keys ] next_orders = ( self.model._base_manager.using(self.db) .filter(reduce(operator.or_, filters)) .values_list(*attnames) .annotate(_order__max=Max("_order") + 1) ) # Create mapping of group values to max order. group_next_orders = dict.fromkeys(group_keys, 0) group_next_orders.update( (tuple(group_key), next_order) for *group_key, next_order in next_orders ) # Assign _order values to new objects. loopIteratorJ = __import__("builtins").iter(obj_groups) while True: try: obj, group_key = __import__("builtins").next(loopIteratorJ) except __import__("builtins").StopIteration: break if getattr(obj, "_order", None) is None: group_next_order = group_next_orders[group_key] obj._order = group_next_order group_next_orders[group_key] += 1 bulk_create.alters_data = True async def abulk_create( self, objs, batch_size=None, ignore_conflicts=False, update_conflicts=False, update_fields=None, unique_fields=None, ): return await sync_to_async(self.bulk_create)( objs=objs, batch_size=batch_size, ignore_conflicts=ignore_conflicts, update_conflicts=update_conflicts, update_fields=update_fields, unique_fields=unique_fields, ) abulk_create.alters_data = True def bulk_update(self, objs, fields, batch_size=None): """ Update the given fields in each of the given objects in the database. """ if batch_size is not None and batch_size <= 0: raise ValueError("Batch size must be a positive integer.") if not fields: raise ValueError("Field names must be given to bulk_update().") objs = tuple(objs) if not all(obj._is_pk_set() for obj in objs): raise ValueError("All bulk_update() objects must have a primary key set.") opts = self.model._meta fields = [opts.get_field(name) for name in fields] if any(not f.concrete for f in fields): raise ValueError("bulk_update() can only be used with concrete fields.") all_pk_fields = set(opts.pk_fields) loopIteratorK = __import__("builtins").iter(opts.all_parents) while True: try: parent = __import__("builtins").next(loopIteratorK) except __import__("builtins").StopIteration: break all_pk_fields.update(parent._meta.pk_fields) if any(f in all_pk_fields for f in fields): raise ValueError("bulk_update() cannot be used with primary key fields.") if not objs: return 0 loopIteratorL = __import__("builtins").iter(objs) while True: try: obj = __import__("builtins").next(loopIteratorL) except __import__("builtins").StopIteration: break obj._prepare_related_fields_for_save( operation_name="bulk_update", fields=fields ) # PK is used twice in the resulting update query, once in the filter # and once in the WHEN. Each field will also have one CAST. self._for_write = True connection = connections[self.db] max_batch_size = connection.ops.bulk_batch_size( [opts.pk, opts.pk, *fields], objs ) batch_size = min(batch_size, max_batch_size) if batch_size else max_batch_size requires_casting = connection.features.requires_casted_case_in_updates batches = (objs[i : i + batch_size] for i in range(0, len(objs), batch_size)) updates = [] loopIteratorAG = __import__("builtins").iter(batches) while True: try: batch_objs = __import__("builtins").next(loopIteratorAG) except __import__("builtins").StopIteration: break update_kwargs = {} loopIteratorAF = __import__("builtins").iter(fields) while True: try: field = __import__("builtins").next(loopIteratorAF) except __import__("builtins").StopIteration: break when_statements = [] loopIteratorM = __import__("builtins").iter(batch_objs) while True: try: obj = __import__("builtins").next(loopIteratorM) except __import__("builtins").StopIteration: break attr = getattr(obj, field.attname) if not hasattr(attr, "resolve_expression"): attr = Value(attr, output_field=field) when_statements.append(When(pk=obj.pk, then=attr)) case_statement = Case(*when_statements, output_field=field) if requires_casting: case_statement = Cast(case_statement, output_field=field) update_kwargs[field.attname] = case_statement updates.append(([obj.pk for obj in batch_objs], update_kwargs)) rows_updated = 0 queryset = self.using(self.db) with transaction.atomic(using=self.db, savepoint=False): loopIteratorN = __import__("builtins").iter(updates) while True: try: pks, update_kwargs = __import__("builtins").next(loopIteratorN) except __import__("builtins").StopIteration: break rows_updated += queryset.filter(pk__in=pks).update(**update_kwargs) return rows_updated bulk_update.alters_data = True async def abulk_update(self, objs, fields, batch_size=None): return await sync_to_async(self.bulk_update)( objs=objs, fields=fields, batch_size=batch_size, ) abulk_update.alters_data = True def get_or_create(self, defaults=None, **kwargs): """ Look up an object with the given kwargs, creating one if necessary. Return a tuple of (object, created), where created is a boolean specifying whether an object was created. """ # The get() needs to be targeted at the write database in order # to avoid potential transaction consistency problems. self._for_write = True try: return self.get(**kwargs), False except self.model.DoesNotExist: params = self._extract_model_params(defaults, **kwargs) # Try to create an object using passed params. try: with transaction.atomic(using=self.db): params = dict(resolve_callables(params)) return self.create(**params), True except IntegrityError: try: return self.get(**kwargs), False except self.model.DoesNotExist: pass raise get_or_create.alters_data = True async def aget_or_create(self, defaults=None, **kwargs): return await sync_to_async(self.get_or_create)( defaults=defaults, **kwargs, ) aget_or_create.alters_data = True def update_or_create(self, defaults=None, create_defaults=None, **kwargs): """ Look up an object with the given kwargs, updating one with defaults if it exists, otherwise create a new one. Optionally, an object can be created with different values than defaults by using create_defaults. Return a tuple (object, created), where created is a boolean specifying whether an object was created. """ update_defaults = defaults or {} if create_defaults is None: create_defaults = update_defaults self._for_write = True with transaction.atomic(using=self.db): # Lock the row so that a concurrent update is blocked until # update_or_create() has performed its save. obj, created = self.select_for_update().get_or_create( create_defaults, **kwargs ) if created: return obj, created loopIteratorO = __import__("builtins").iter(resolve_callables(update_defaults)) while True: try: k, v = __import__("builtins").next(loopIteratorO) except __import__("builtins").StopIteration: break setattr(obj, k, v) update_fields = set(update_defaults) concrete_field_names = self.model._meta._non_pk_concrete_field_names # update_fields does not support non-concrete fields. if concrete_field_names.issuperset(update_fields): # Add fields which are set on pre_save(), e.g. auto_now fields. # This is to maintain backward compatibility as these fields # are not updated unless explicitly specified in the # update_fields list. pk_fields = self.model._meta.pk_fields loopIteratorP = __import__("builtins").iter(self.model._meta.local_concrete_fields) while True: try: field = __import__("builtins").next(loopIteratorP) except __import__("builtins").StopIteration: break if not ( field in pk_fields or field.__class__.pre_save is Field.pre_save ): update_fields.add(field.name) if field.name != field.attname: update_fields.add(field.attname) obj.save(using=self.db, update_fields=update_fields) else: obj.save(using=self.db) return obj, False update_or_create.alters_data = True async def aupdate_or_create(self, defaults=None, create_defaults=None, **kwargs): return await sync_to_async(self.update_or_create)( defaults=defaults, create_defaults=create_defaults, **kwargs, ) aupdate_or_create.alters_data = True def _extract_model_params(self, defaults, **kwargs): """ Prepare `params` for creating a model instance based on the given kwargs; for use by get_or_create(). """ defaults = defaults or {} params = {k: v for k, v in kwargs.items() if LOOKUP_SEP not in k} params.update(defaults) property_names = self.model._meta._property_names invalid_params = [] for param in params: try: self.model._meta.get_field(param) except exceptions.FieldDoesNotExist: # It's okay to use a model's property if it has a setter. if not (param in property_names and getattr(self.model, param).fset): invalid_params.append(param) if invalid_params: raise exceptions.FieldError( "Invalid field name(s) for model %s: '%s'." % ( self.model._meta.object_name, "', '".join(sorted(invalid_params)), ) ) return params def _earliest(self, *fields): """ Return the earliest object according to fields (if given) or by the model's Meta.get_latest_by. """ if fields: order_by = fields else: order_by = getattr(self.model._meta, "get_latest_by") if order_by and not isinstance(order_by, (tuple, list)): order_by = (order_by,) if order_by is None: raise ValueError( "earliest() and latest() require either fields as positional " "arguments or 'get_latest_by' in the model's Meta." ) obj = self._chain() obj.query.set_limits(high=1) obj.query.clear_ordering(force=True) obj.query.add_ordering(*order_by) return obj.get() def earliest(self, *fields): if self.query.is_sliced: raise TypeError("Cannot change a query once a slice has been taken.") return self._earliest(*fields) async def aearliest(self, *fields): return await sync_to_async(self.earliest)(*fields) def latest(self, *fields): """ Return the latest object according to fields (if given) or by the model's Meta.get_latest_by. """ if self.query.is_sliced: raise TypeError("Cannot change a query once a slice has been taken.") return self.reverse()._earliest(*fields) async def alatest(self, *fields): return await sync_to_async(self.latest)(*fields) def first(self): """Return the first object of a query or None if no match is found.""" if self.ordered or not self.query.default_ordering: queryset = self else: self._check_ordering_first_last_queryset_aggregation(method="first") queryset = self.order_by("pk") loopIteratorQ = __import__("builtins").iter(queryset[:1]) while True: try: obj = __import__("builtins").next(loopIteratorQ) except __import__("builtins").StopIteration: break return obj async def afirst(self): return await sync_to_async(self.first)() def last(self): """Return the last object of a query or None if no match is found.""" if self.ordered or not self.query.default_ordering: queryset = self.reverse() else: self._check_ordering_first_last_queryset_aggregation(method="last") queryset = self.order_by("-pk") loopIteratorR = __import__("builtins").iter(queryset[:1]) while True: try: obj = __import__("builtins").next(loopIteratorR) except __import__("builtins").StopIteration: break return obj async def alast(self): return await sync_to_async(self.last)() def in_bulk(self, id_list=None, *, field_name="pk"): """ Return a dictionary mapping each of the given IDs to the object with that ID. If `id_list` isn't provided, evaluate the entire QuerySet. """ if self.query.is_sliced: raise TypeError("Cannot use 'limit' or 'offset' with in_bulk().") if id_list is not None and not id_list: return {} opts = self.model._meta unique_fields = [ constraint.fields[0] for constraint in opts.total_unique_constraints if len(constraint.fields) == 1 ] if ( field_name != "pk" and not opts.get_field(field_name).unique and field_name not in unique_fields and self.query.distinct_fields != (field_name,) ): raise ValueError( "in_bulk()'s field_name must be a unique field but %r isn't." % field_name ) qs = self def get_obj(obj): return obj if issubclass(self._iterable_class, ModelIterable): # Raise an AttributeError if field_name is deferred. get_key = operator.attrgetter(field_name) elif issubclass(self._iterable_class, ValuesIterable): if field_name not in self.query.values_select: qs = qs.values(field_name, *self.query.values_select) def get_obj(obj): # noqa: F811 # We can safely mutate the dictionaries returned by # ValuesIterable here, since they are limited to the scope # of this function, and get_key runs before get_obj. del obj[field_name] return obj get_key = operator.itemgetter(field_name) elif issubclass(self._iterable_class, ValuesListIterable): try: field_index = self.query.values_select.index(field_name) except ValueError: # field_name is missing from values_select, so add it. field_index = 0 if issubclass(self._iterable_class, NamedValuesListIterable): kwargs = {"named": True} else: kwargs = {} get_obj = operator.itemgetter(slice(1, None)) qs = qs.values_list(field_name, *self.query.values_select, **kwargs) get_key = operator.itemgetter(field_index) elif issubclass(self._iterable_class, FlatValuesListIterable): if self.query.values_select == (field_name,): # Mapping field_name to itself. get_key = get_obj else: # Transform it back into a non-flat values_list(). qs = qs.values_list(field_name, *self.query.values_select) get_key = operator.itemgetter(0) get_obj = operator.itemgetter(1) else: raise TypeError( f"in_bulk() cannot be used with {self._iterable_class.__name__}." ) if id_list is not None: filter_key = "{}__in".format(field_name) id_list = tuple(id_list) batch_size = connections[self.db].ops.bulk_batch_size([opts.pk], id_list) # If the database has a limit on the number of query parameters # (e.g. SQLite), retrieve objects in batches if necessary. if batch_size and batch_size < len(id_list): results = () loopIteratorS = __import__("builtins").iter(range(0, len(id_list), batch_size)) while True: try: offset = __import__("builtins").next(loopIteratorS) except __import__("builtins").StopIteration: break batch = id_list[offset : offset + batch_size] results += tuple(qs.filter(**{filter_key: batch})) qs = results else: qs = qs.filter(**{filter_key: id_list}) else: qs = qs._chain() return {get_key(obj): get_obj(obj) for obj in qs} async def ain_bulk(self, id_list=None, *, field_name="pk"): return await sync_to_async(self.in_bulk)( id_list=id_list, field_name=field_name, ) def delete(self): """Delete the records in the current QuerySet.""" self._not_support_combined_queries("delete") if self.query.is_sliced: raise TypeError("Cannot use 'limit' or 'offset' with delete().") if self.query.distinct_fields: raise TypeError("Cannot call delete() after .distinct(*fields).") if self._fields is not None: raise TypeError("Cannot call delete() after .values() or .values_list()") del_query = self._chain() # The delete is actually 2 queries - one to find related objects, # and one to delete. Make sure that the discovery of related # objects is performed on the same database as the deletion. del_query._for_write = True # Disable non-supported fields. del_query.query.select_for_update = False del_query.query.select_related = False del_query.query.clear_ordering(force=True) collector = Collector(using=del_query.db, origin=self) collector.collect(del_query) num_deleted, num_deleted_per_model = collector.delete() # Clear the result cache, in case this QuerySet gets reused. self._result_cache = None return num_deleted, num_deleted_per_model delete.alters_data = True delete.queryset_only = True async def adelete(self): return await sync_to_async(self.delete)() adelete.alters_data = True adelete.queryset_only = True def _raw_delete(self, using): """ Delete objects found from the given queryset in single direct SQL query. No signals are sent and there is no protection for cascades. """ query = self.query.clone() query.__class__ = sql.DeleteQuery return query.get_compiler(using).execute_sql(ROW_COUNT) _raw_delete.alters_data = True def update(self, **kwargs): """ Update all elements in the current QuerySet, setting all the given fields to the appropriate values. """ self._not_support_combined_queries("update") if self.query.is_sliced: raise TypeError("Cannot update a query once a slice has been taken.") if self.query.distinct_fields: raise TypeError("Cannot call update() after .distinct(*fields).") self._for_write = True query = self.query.chain(sql.UpdateQuery) query.add_update_values(kwargs) # Inline annotations in order_by(), if possible. new_order_by = [] loopIteratorT = __import__("builtins").iter(query.order_by) while True: try: col = __import__("builtins").next(loopIteratorT) except __import__("builtins").StopIteration: break alias = col descending = False if isinstance(alias, str) and alias.startswith("-"): alias = alias.removeprefix("-") descending = True if annotation := query.annotations.get(alias): if getattr(annotation, "contains_aggregate", False): raise exceptions.FieldError( f"Cannot update when ordering by an aggregate: {annotation}" ) if descending: annotation = annotation.desc() new_order_by.append(annotation) else: new_order_by.append(col) query.order_by = tuple(new_order_by) # Clear SELECT clause as all annotation references were inlined by # add_update_values() already. query.clear_select_clause() with transaction.mark_for_rollback_on_error(using=self.db): rows = query.get_compiler(self.db).execute_sql(ROW_COUNT) self._result_cache = None return rows update.alters_data = True async def aupdate(self, **kwargs): return await sync_to_async(self.update)(**kwargs) aupdate.alters_data = True def _update(self, values, returning_fields=None): """ A version of update() that accepts field objects instead of field names. Used primarily for model saving and not intended for use by general code (it requires too much poking around at model internals to be useful at that level). """ if self.query.is_sliced: raise TypeError("Cannot update a query once a slice has been taken.") query = self.query.chain(sql.UpdateQuery) query.add_update_fields(values) # Clear any annotations so that they won't be present in subqueries. query.annotations = {} self._result_cache = None if returning_fields is None: return query.get_compiler(self.db).execute_sql(ROW_COUNT) return query.get_compiler(self.db).execute_returning_sql(returning_fields) _update.alters_data = True _update.queryset_only = False def exists(self): """ Return True if the QuerySet would have any results, False otherwise. """ if self._result_cache is None: return self.query.has_results(using=self.db) return bool(self._result_cache) async def aexists(self): return await sync_to_async(self.exists)() def contains(self, obj): """ Return True if the QuerySet contains the provided obj, False otherwise. """ self._not_support_combined_queries("contains") if self._fields is not None: raise TypeError( "Cannot call QuerySet.contains() after .values() or .values_list()." ) try: if obj._meta.concrete_model != self.model._meta.concrete_model: return False except AttributeError: raise TypeError("'obj' must be a model instance.") if not obj._is_pk_set(): raise ValueError("QuerySet.contains() cannot be used on unsaved objects.") if self._result_cache is not None: return obj in self._result_cache return self.filter(pk=obj.pk).exists() async def acontains(self, obj): return await sync_to_async(self.contains)(obj=obj) def _prefetch_related_objects(self): # This method can only be called once the result cache has been filled. prefetch_related_objects(self._result_cache, *self._prefetch_related_lookups) self._prefetch_done = True def explain(self, *, format=None, **options): """ Runs an EXPLAIN on the SQL query this QuerySet would perform, and returns the results. """ return self.query.explain(using=self.db, format=format, **options) async def aexplain(self, *, format=None, **options): return await sync_to_async(self.explain)(format=format, **options) ################################################## # PUBLIC METHODS THAT RETURN A QUERYSET SUBCLASS # ################################################## def raw(self, raw_query, params=(), translations=None, using=None): if using is None: using = self.db qs = RawQuerySet( raw_query, model=self.model, params=params, translations=translations, using=using, fetch_mode=self._fetch_mode, ) qs._prefetch_related_lookups = self._prefetch_related_lookups[:] return qs def _values(self, *fields, **expressions): clone = self._chain() if expressions: # RemovedInDjango70Warning: When the deprecation ends, deindent as: # clone = clone.annotate(**expressions) with warnings.catch_warnings( action="ignore", category=RemovedInDjango70Warning ): clone = clone.annotate(**expressions) clone._fields = fields clone.query.set_values(fields) return clone def values(self, *fields, **expressions): fields += tuple(expressions) clone = self._values(*fields, **expressions) clone._iterable_class = ValuesIterable return clone def values_list(self, *fields, flat=False, named=False): if flat and named: raise TypeError("'flat' and 'named' can't be used together.") if flat: if len(fields) > 1: raise TypeError( "'flat' is not valid when values_list is called with more than one " "field." ) elif not fields: # RemovedInDjango70Warning: When the deprecation ends, replace # with: # raise TypeError( # "'flat' is not valid when values_list is called with no " # "fields." # ) warnings.warn( "Calling values_list() with no field name and flat=True " "is deprecated. Pass an explicit field name instead, like " "'pk'.", RemovedInDjango70Warning, ) fields = [self.model._meta.concrete_fields[0].attname] field_names = {f: False for f in fields if not hasattr(f, "resolve_expression")} _fields = [] expressions = {} counter = 1 for field in fields: field_name = field expression = None if hasattr(field, "resolve_expression"): field_name = getattr( field, "default_alias", field.__class__.__name__.lower() ) expression = field # For backward compatibility reasons expressions are always # prefixed with the counter even if their default alias doesn't # collide with field names. Changing this logic could break # some usage of named=True. seen = True elif seen := field_names[field_name]: expression = F(field_name) if seen: field_name_prefix = field_name while (field_name := f"{field_name_prefix}{counter}") in field_names: counter += 1 if expression is not None: expressions[field_name] = expression field_names[field_name] = True _fields.append(field_name) clone = self._values(*_fields, **expressions) clone._iterable_class = ( NamedValuesListIterable if named else FlatValuesListIterable if flat else ValuesListIterable ) return clone def dates(self, field_name, kind, order="ASC"): """ Return a list of date objects representing all available dates for the given field_name, scoped to 'kind'. """ if kind not in ("year", "month", "week", "day"): raise ValueError("'kind' must be one of 'year', 'month', 'week', or 'day'.") if order not in ("ASC", "DESC"): raise ValueError("'order' must be either 'ASC' or 'DESC'.") return ( self.annotate( datefield=Trunc(field_name, kind, output_field=DateField()), plain_field=F(field_name), ) .values_list("datefield", flat=True) .distinct() .filter(plain_field__isnull=False) .order_by(("-" if order == "DESC" else "") + "datefield") ) def datetimes(self, field_name, kind, order="ASC", tzinfo=None): """ Return a list of datetime objects representing all available datetimes for the given field_name, scoped to 'kind'. """ if kind not in ("year", "month", "week", "day", "hour", "minute", "second"): raise ValueError( "'kind' must be one of 'year', 'month', 'week', 'day', " "'hour', 'minute', or 'second'." ) if order not in ("ASC", "DESC"): raise ValueError("'order' must be either 'ASC' or 'DESC'.") if settings.USE_TZ: if tzinfo is None: tzinfo = timezone.get_current_timezone() else: tzinfo = None return ( self.annotate( datetimefield=Trunc( field_name, kind, output_field=DateTimeField(), tzinfo=tzinfo, ), plain_field=F(field_name), ) .values_list("datetimefield", flat=True) .distinct() .filter(plain_field__isnull=False) .order_by(("-" if order == "DESC" else "") + "datetimefield") ) def none(self): """Return an empty QuerySet.""" clone = self._chain() clone.query.set_empty() return clone ################################################################## # PUBLIC METHODS THAT ALTER ATTRIBUTES AND RETURN A NEW QUERYSET # ################################################################## def all(self): """ Return a new QuerySet that is a copy of the current one. This allows a QuerySet to proxy for a model manager in some cases. """ return self._chain() def filter(self, *args, **kwargs): """ Return a new QuerySet instance with the args ANDed to the existing set. """ self._not_support_combined_queries("filter") return self._filter_or_exclude(False, args, kwargs) def exclude(self, *args, **kwargs): """ Return a new QuerySet instance with NOT (args) ANDed to the existing set. """ self._not_support_combined_queries("exclude") return self._filter_or_exclude(True, args, kwargs) def _filter_or_exclude(self, negate, args, kwargs): if (args or kwargs) and self.query.is_sliced: raise TypeError("Cannot filter a query once a slice has been taken.") clone = self._chain() if self._defer_next_filter: self._defer_next_filter = False clone._deferred_filter = negate, args, kwargs else: clone._filter_or_exclude_inplace(negate, args, kwargs) return clone def _filter_or_exclude_inplace(self, negate, args, kwargs): if invalid_kwargs := PROHIBITED_FILTER_KWARGS.intersection(kwargs): invalid_kwargs_str = ", ".join(f"'{k}'" for k in sorted(invalid_kwargs)) raise TypeError(f"The following kwargs are invalid: {invalid_kwargs_str}") if negate: self._query.add_q(~Q(*args, **kwargs)) else: self._query.add_q(Q(*args, **kwargs)) def complex_filter(self, filter_obj): """ Return a new QuerySet instance with filter_obj added to the filters. filter_obj can be a Q object or a dictionary of keyword lookup arguments. This exists to support framework features such as 'limit_choices_to', and usually it will be more natural to use other methods. """ if isinstance(filter_obj, Q): clone = self._chain() clone.query.add_q(filter_obj) return clone else: return self._filter_or_exclude(False, args=(), kwargs=filter_obj) def _combinator_query(self, combinator, *other_qs, all=False): # Clone the query to inherit the select list and everything clone = self._chain() # Clear limits and ordering so they can be reapplied clone.query.clear_ordering(force=True) clone.query.default_ordering = True self._clear_ordering_in_combined_queries(clone.query, other_qs) clone.query.clear_limits() clone.query.combinator = combinator clone.query.combinator_all = all return clone def union(self, *other_qs, all=False): # If the query is an EmptyQuerySet, combine all nonempty querysets. if isinstance(self, EmptyQuerySet): qs = [q for q in other_qs if not isinstance(q, EmptyQuerySet)] if not qs: return self if len(qs) == 1: return qs[0] return qs[0]._combinator_query("union", *qs[1:], all=all) elif not other_qs: return self return self._combinator_query("union", *other_qs, all=all) def intersection(self, *other_qs): # If any query is an EmptyQuerySet, return it. if isinstance(self, EmptyQuerySet): return self loopIteratorU = __import__("builtins").iter(other_qs) while True: try: other = __import__("builtins").next(loopIteratorU) except __import__("builtins").StopIteration: break if isinstance(other, EmptyQuerySet): return other return self._combinator_query("intersection", *other_qs) def difference(self, *other_qs): # If the query is an EmptyQuerySet, return it. if isinstance(self, EmptyQuerySet): return self return self._combinator_query("difference", *other_qs) def select_for_update(self, nowait=False, skip_locked=False, of=(), no_key=False): """ Return a new QuerySet instance that will select objects with a FOR UPDATE lock. """ if nowait and skip_locked: raise ValueError("The nowait option cannot be used with skip_locked.") obj = self._chain() obj._for_write = True obj.query.select_for_update = True obj.query.select_for_update_nowait = nowait obj.query.select_for_update_skip_locked = skip_locked obj.query.select_for_update_of = of obj.query.select_for_no_key_update = no_key return obj def select_related(self, *fields): """ Return a new QuerySet instance that will select related objects. If fields are specified, they must be ForeignKey fields and only those related objects are included in the selection. If select_related(None) is called, clear the list. """ self._not_support_combined_queries("select_related") if self._fields is not None: raise TypeError( "Cannot call select_related() after .values() or .values_list()" ) obj = self._chain() if fields == (None,): obj.query.select_related = False elif fields: obj.query.add_select_related(fields) else: # RemovedInDjango70Warning: when the deprecation ends, raise a # TypeError instead. warn_about_external_use( "Calling select_related() with no arguments is deprecated. " "Specify the fields to fetch instead.", category=RemovedInDjango70Warning, skip_name_prefixes=("django.db.models",), ) obj.query.select_related = True return obj def prefetch_related(self, *lookups): """ Return a new QuerySet instance that will prefetch the specified Many-To-One and Many-To-Many related objects when the QuerySet is evaluated. When prefetch_related() is called more than once, append to the list of prefetch lookups. If prefetch_related(None) is called, clear the list. """ self._not_support_combined_queries("prefetch_related") clone = self._chain() if lookups == (None,): clone._prefetch_related_lookups = () else: loopIteratorV = __import__("builtins").iter(lookups) while True: try: lookup = __import__("builtins").next(loopIteratorV) except __import__("builtins").StopIteration: break if isinstance(lookup, Prefetch): lookup = lookup.prefetch_to lookup = lookup.split(LOOKUP_SEP, 1)[0] if lookup in self.query._filtered_relations: raise ValueError( "prefetch_related() is not supported with FilteredRelation." ) clone._prefetch_related_lookups = clone._prefetch_related_lookups + lookups return clone def annotate(self, *args, **kwargs): """ Return a query set in which the returned objects have been annotated with extra data or aggregations. """ self._not_support_combined_queries("annotate") return self._annotate(args, kwargs, select=True) def alias(self, *args, **kwargs): """ Return a query set with added aliases for extra data or aggregations. """ self._not_support_combined_queries("alias") return self._annotate(args, kwargs, select=False) def _annotate(self, args, kwargs, select=True): self._validate_values_are_expressions( args + tuple(kwargs.values()), method_name="annotate" ) annotations = {} for arg in args: # The default_alias property raises TypeError if default_alias # can't be set automatically or AttributeError if it isn't an # attribute. try: if arg.default_alias in kwargs: raise ValueError( "The named annotation '%s' conflicts with the " "default name for another annotation." % arg.default_alias ) except (TypeError, AttributeError): raise TypeError("Complex annotations require an alias") annotations[arg.default_alias] = arg annotations.update(kwargs) clone = self._chain() names = self._fields if names is None: names = set( chain.from_iterable( ( (field.name, field.attname) if hasattr(field, "attname") else (field.name,) ) for field in self.model._meta.get_fields() ) ) loopIteratorW = __import__("builtins").iter(annotations.items()) while True: try: alias, annotation = __import__("builtins").next(loopIteratorW) except __import__("builtins").StopIteration: break if alias in names: raise ValueError( "The annotation '%s' conflicts with a field on " "the model." % alias ) if isinstance(annotation, FilteredRelation): clone.query.add_filtered_relation(annotation, alias) else: clone.query.add_annotation( annotation, alias, select=select, ) loopIteratorX = __import__("builtins").iter(clone.query.annotations.items()) while True: try: alias, annotation = __import__("builtins").next(loopIteratorX) except __import__("builtins").StopIteration: break if alias in annotations and annotation.contains_aggregate: if clone._fields is None: clone.query.group_by = True else: clone.query.set_group_by() break return clone def order_by(self, *field_names): """Return a new QuerySet instance with the ordering changed.""" if self.query.is_sliced: raise TypeError("Cannot reorder a query once a slice has been taken.") obj = self._chain() obj.query.clear_ordering(force=True, clear_default=False) obj.query.add_ordering(*field_names) return obj def distinct(self, *field_names): """ Return a new QuerySet instance that will select only distinct results. """ self._not_support_combined_queries("distinct") if self.query.is_sliced: raise TypeError( "Cannot create distinct fields once a slice has been taken." ) obj = self._chain() obj.query.add_distinct_fields(*field_names) return obj def extra( self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None, ): """Add extra SQL fragments to the query.""" self._not_support_combined_queries("extra") if self.query.is_sliced: raise TypeError("Cannot change a query once a slice has been taken.") clone = self._chain() clone.query.add_extra(select, select_params, where, params, tables, order_by) return clone def reverse(self): """Reverse the ordering of the QuerySet.""" if self.query.is_sliced: raise TypeError("Cannot reverse a query once a slice has been taken.") clone = self._chain() clone.query.standard_ordering = not clone.query.standard_ordering return clone def defer(self, *fields): """ Defer the loading of data for certain fields until they are accessed. Add the set of deferred fields to any existing set of deferred fields. The only exception to this is if None is passed in as the only parameter, in which case remove all deferrals. """ self._not_support_combined_queries("defer") if self._fields is not None: raise TypeError("Cannot call defer() after .values() or .values_list()") clone = self._chain() if fields == (None,): clone.query.clear_deferred_loading() else: clone.query.add_deferred_loading(fields) return clone def only(self, *fields): """ Essentially, the opposite of defer(). Only the fields passed into this method and that are not already specified as deferred are loaded immediately when the queryset is evaluated. """ self._not_support_combined_queries("only") if self._fields is not None: raise TypeError("Cannot call only() after .values() or .values_list()") if fields == (None,): # Can only pass None to defer(), not only(), as the rest option. # That won't stop people trying to do this, so let's be explicit. raise TypeError("Cannot pass None as an argument to only().") loopIteratorY = __import__("builtins").iter(fields) while True: try: field = __import__("builtins").next(loopIteratorY) except __import__("builtins").StopIteration: break field = field.split(LOOKUP_SEP, 1)[0] if field in self.query._filtered_relations: raise ValueError("only() is not supported with FilteredRelation.") clone = self._chain() clone.query.add_immediate_loading(fields) return clone def using(self, alias): """Select which database this QuerySet should execute against.""" clone = self._chain() clone._db = alias return clone def fetch_mode(self, fetch_mode): """Set the fetch mode for the QuerySet.""" clone = self._chain() clone._fetch_mode = fetch_mode return clone ################################### # PUBLIC INTROSPECTION ATTRIBUTES # ################################### @property def ordered(self): """ Return True if the QuerySet is ordered -- i.e. has an order_by() clause or a default ordering on the model (or is empty). """ if isinstance(self, EmptyQuerySet): return True if self.query.extra_order_by or self.query.order_by: return True elif ( self.query.default_ordering and self.query.get_meta().ordering and # A default ordering doesn't affect GROUP BY queries. not self.query.group_by ): return True else: return False @property def totally_ordered(self): """ Returns True if the QuerySet is ordered and the ordering is deterministic. This requires that the ordering includes a field (or set of fields) that is unique and non-nullable. For queries involving a GROUP BY clause, the model's default ordering is ignored. Ordering specified via .extra(order_by=...) is also ignored. """ if not self.ordered: return False ordering = self.query.order_by if not ordering and self.query.default_ordering: ordering = self.query.get_meta().ordering if not ordering: return False opts = self.model._meta pk_fields = {f.attname for f in opts.pk_fields} candidate_fields = set() for part in ordering: # Search for single field providing a total ordering. field_name = None if isinstance(part, str): field_name = part.lstrip("-") elif isinstance(part, F): field_name = part.name elif isinstance(part, OrderBy) and isinstance(part.expression, F): field_name = part.expression.name if annotation_col := self.query.annotations.get(field_name): if isinstance(annotation_col, Col): if annotation_col.alias == self.query.base_table: candidate_fields.add(annotation_col.target) elif isinstance(annotation_col, ColPairs): candidate_fields |= { c.target for c in annotation_col.get_cols() if c.alias == self.query.base_table } elif field_name: if field_name == "pk": return True # Normalize attname references by using get_field(). try: field = opts.get_field(field_name) except exceptions.FieldDoesNotExist: # Could be "?" for random ordering or a related field # lookup. Skip this part of introspection for now. continue else: # Ordering by a related field name orders by the referenced # model's ordering. Skip this introspection for now. if field.remote_field and field_name == field.name: continue candidate_fields.add(field) candidate_attnames = set() loopIteratorZ = __import__("builtins").iter(candidate_fields) while True: try: field = __import__("builtins").next(loopIteratorZ) except __import__("builtins").StopIteration: break if field.unique and not field.null: return True candidate_attnames.add(field.attname) # Account for members of a CompositePrimaryKey. if candidate_attnames.issuperset(pk_fields): return True # No single total ordering field, try unique_together and total # unique constraints. constraint_field_names = ( *opts.unique_together, *(constraint.fields for constraint in opts.total_unique_constraints), ) for field_names in constraint_field_names: # Normalize attname references by using get_field(). try: fields = [opts.get_field(field_name) for field_name in field_names] except exceptions.FieldDoesNotExist: continue # Composite unique constraints containing a nullable column # cannot ensure total ordering. if any(field.null for field in fields): continue if candidate_attnames.issuperset(field.attname for field in fields): return True return False @property def db(self): """Return the database used if this query is executed now.""" if self._for_write: return self._db or router.db_for_write(self.model, **self._hints) return self._db or router.db_for_read(self.model, **self._hints) ################### # PRIVATE METHODS # ################### def _insert( self, objs, fields, returning_fields=None, raw=False, using=None, on_conflict=None, update_fields=None, unique_fields=None, ): """ Insert a new record for the given model. This provides an interface to the InsertQuery class and is how Model.save() is implemented. """ self._for_write = True if using is None: using = self.db query = sql.InsertQuery( self.model, on_conflict=on_conflict, update_fields=update_fields, unique_fields=unique_fields, ) query.insert_values(fields, objs, raw=raw) return query.get_compiler(using=using).execute_sql(returning_fields) _insert.alters_data = True _insert.queryset_only = False def _batched_insert( self, objs, fields, batch_size, on_conflict=None, update_fields=None, unique_fields=None, ): """ Helper method for bulk_create() to insert objs one batch at a time. """ connection = connections[self.db] ops = connection.ops max_batch_size = max(ops.bulk_batch_size(fields, objs), 1) batch_size = min(batch_size, max_batch_size) if batch_size else max_batch_size inserted_rows = [] returning_fields = ( self.model._meta.db_returning_fields if ( connection.features.can_return_rows_from_bulk_insert and (on_conflict is None or on_conflict == OnConflict.UPDATE) ) else None ) batches = [objs[i : i + batch_size] for i in range(0, len(objs), batch_size)] if len(batches) > 1: context = transaction.atomic(using=self.db, savepoint=False) else: context = nullcontext() with context: loopIteratorAA = __import__("builtins").iter(batches) while True: try: item = __import__("builtins").next(loopIteratorAA) except __import__("builtins").StopIteration: break inserted_rows.extend( self._insert( item, fields=fields, using=self.db, on_conflict=on_conflict, update_fields=update_fields, unique_fields=unique_fields, returning_fields=returning_fields, ) ) return inserted_rows def _disable_cloning(self): """ Prevent calls to _chain() from creating a new QuerySet via _clone(). All subsequent QuerySet mutations will occur on this instance until _enable_cloning() is used. """ self._cloning_enabled = False return self def _enable_cloning(self): """ Allow calls to _chain() to create a new QuerySet via _clone(). Restores the default behavior where any QuerySet mutation will return a new QuerySet instance. Necessary only when there has been a _disable_cloning() call previously. """ self._cloning_enabled = True return self def _avoid_cloning(self): """ Temporarily prevent QuerySet _clone() operations, restoring the default behavior on exit. For the duration of the context managed statement, all operations (e.g. filter(), exclude(), etc.) will mutate the same QuerySet instance. @contextlib.contextmanager is intentionally not used for performance reasons. """ return PreventQuerySetCloning(self) def _chain(self): """ Return a copy of the current QuerySet that's ready for another operation. If the QuerySet has opted in to in-place mutations via _disable_cloning() temporarily, the copy doesn't occur and instead the same QuerySet instance will be modified. """ if not self._cloning_enabled: obj = self else: obj = self._clone() if obj._sticky_filter: obj.query.filter_is_sticky = True obj._sticky_filter = False return obj def _clone(self): """ Return a copy of the current QuerySet. A lightweight alternative to deepcopy(). """ c = self.__class__( model=self.model, query=self.query.chain(), using=self._db, hints=self._hints, ) c._sticky_filter = self._sticky_filter c._for_write = self._for_write c._prefetch_related_lookups = self._prefetch_related_lookups[:] c._known_related_objects = self._known_related_objects c._iterable_class = self._iterable_class c._fetch_mode = self._fetch_mode c._fields = self._fields return c def _fetch_all(self): if self._result_cache is None: self._result_cache = list(self._iterable_class(self)) if self._prefetch_related_lookups and not self._prefetch_done: self._prefetch_related_objects() def _next_is_sticky(self): """ Indicate that the next filter call and the one following that should be treated as a single filter. This is only important when it comes to determining when to reuse tables for many-to-many filters. Required so that we can filter naturally on the results of related managers. This doesn't return a clone of the current QuerySet (it returns "self"). The method is only used internally and should be immediately followed by a filter() that does create a clone. """ self._sticky_filter = True return self def _merge_sanity_check(self, other): """Check that two QuerySet classes may be merged.""" if self._fields is not None and ( set(self.query.values_select) != set(other.query.values_select) or set(self.query.extra_select) != set(other.query.extra_select) or set(self.query.annotation_select) != set(other.query.annotation_select) ): raise TypeError( "Merging '%s' classes must involve the same values in each case." % self.__class__.__name__ ) def _merge_known_related_objects(self, other): """ Keep track of all known related objects from either QuerySet instance. """ loopIteratorAB = __import__("builtins").iter(other._known_related_objects.items()) while True: try: field, objects = __import__("builtins").next(loopIteratorAB) except __import__("builtins").StopIteration: break self._known_related_objects.setdefault(field, {}).update(objects) def resolve_expression(self, *args, **kwargs): query = self.query.resolve_expression(*args, **kwargs) query._db = self._db return query resolve_expression.queryset_only = True def _add_hints(self, **hints): """ Update hinting information for use by routers. Add new key/values or overwrite existing key/values. """ self._hints.update(hints) def _has_filters(self): """ Check if this QuerySet has any filtering going on. This isn't equivalent with checking if all objects are present in results, for example, qs[1:]._has_filters() -> False. """ return self.query.has_filters() @staticmethod def _validate_values_are_expressions(values, method_name): invalid_args = sorted( str(arg) for arg in values if not hasattr(arg, "resolve_expression") ) if invalid_args: raise TypeError( "QuerySet.%s() received non-expression(s): %s." % ( method_name, ", ".join(invalid_args), ) ) def _not_support_combined_queries(self, operation_name): if self.query.combinator: raise NotSupportedError( "Calling QuerySet.%s() after %s() is not supported." % (operation_name, self.query.combinator) ) def _check_operator_queryset(self, other, operator_): if self.query.combinator or other.query.combinator: raise TypeError(f"Cannot use {operator_} operator with combined queryset.") def _check_ordering_first_last_queryset_aggregation(self, method): if ( isinstance(self.query.group_by, tuple) # Raise if the pk fields are not in the group_by. and self.model._meta.pk not in {col.output_field for col in self.query.group_by} and set(self.model._meta.pk_fields).difference( {col.target for col in self.query.group_by} ) ): raise TypeError( f"Cannot use QuerySet.{method}() on an unordered queryset performing " f"aggregation. Add an ordering with order_by()." ) def _clear_ordering_in_combined_queries(self, cloned_query, other_qs): combined_queries = [self.query] loopIteratorAC = __import__("builtins").iter(other_qs) while True: try: qs = __import__("builtins").next(loopIteratorAC) except __import__("builtins").StopIteration: break query = qs.query.clone() query.clear_ordering(force=False, clear_default=False) combined_queries.append(query) cloned_query.combined_queries = tuple(combined_queries)

Loading feature diagnosis…

Source regions

Feature contributions

Feature contributions

FeatureValueContribution
(log-odds)
Halstead volumeHow much symbolic information the code contains. It combines the total number of operators and values with the number of distinct ones.104006.253−3432.206
Source linesThe number of non-empty source lines.2272+908.8
Byte entropyHow varied the bytes in the source text are. Repeated bytes give a lower value; a more even mixture gives a higher value.4.303−6.455

Intercept 8.87 + feature contributions = -2520.991 (log-odds).
Score = sigmoid(-2520.991) = 0.

Feature contributions

FeatureValueContribution
(log-odds)
Comment layout frequencyHow frequently the layout switches between lines containing only comments or whitespace and lines containing code.2273−79.444
Indentation frequencyHow rapidly indentation changes from line to line.1942+66.434
Number layout frequencyHow rapidly the number of numeric values per line changes through the code.1942−44.142
Identifier layout (vertical)How rapidly the visual pattern of identifier characters changes from top to bottom.2271.933+31.347
Comment layout (horizontal)How rapidly the visual pattern of comment characters changes from left to right.102.977+0.857
Identifier layout (horizontal)How rapidly the visual pattern of identifier characters changes from left to right. It measures spatial frequency, not the meaning of the names.102.968−0.696
Operator visual areaThe share of the code’s visual area occupied by operators such as +, =, and *.0.057+0.389

Intercept 0.07 + feature contributions = -25.184 (log-odds).
Score = sigmoid(-25.184) = 0.

Score0.52
Score1260
Run 1

This code is extremely difficult to read. The structure is disorganized, with many long methods and deeply nested conditionals. There is heavy repetition of awkward manual iteration patterns instead of using standard Python loops (e.g., while True with __import__('builtins').next), which drastically hurts clarity and flow. Intent is often buried under layers of validation, comments, and conditional logic. Many methods are hundreds of lines long and combine multiple responsibilities, violating action granularity and code length principles. Nesting frequently exceeds four or five levels, making it hard to track logic. The reading flow is unnatural due to scattered helper methods and inconsistent abstraction. While some docstrings exist, they are overwhelmed by the volume of tangled logic. Overall, this code is closer to unreadable than readable, scoring very low on most criteria.

Run 2

This code is extremely unreadable. It features bizarre, obfuscated loop constructs using `__import__('builtins').iter()` and `.next()` with `try/except StopIteration` instead of standard `for` loops, which severely harms readability and clarity of intent. There are deeply nested conditionals and loops, especially in methods like `bulk_create`, `bulk_update`, and `update_or_create`. Many methods are excessively long, mixing validation, query construction, and database operations. While the code has clear section headers and docstrings, the overall structure is tangled, and the unnatural iteration patterns create a disorienting reading flow. Action granularity is inconsistent, with multiple operations often crammed into single lines or confusing while-loop blocks.

Run 3

This code is extremely difficult to read due to several severe issues. The most egregious is the bizarre pattern of replacing native Python `for` loops with manual `while True` loops calling `__import__('builtins').iter()` and `__import__('builtins').next()`, which is both unidiomatic and highly obfuscated. This single issue decimates the reading flow and clarity of intent. The file is a massive, monolithic class with hundreds of methods, making logical organization appear tangled. There is extensive nesting, especially in methods like `bulk_create`, `bulk_update`, and `aiterator`. While comments are sometimes helpful, the action granularity is poor due to the loop replacements, and the overall code length is bloated by this same anti-pattern. The presence of good docstrings and structured sections is negated by the unreadable control flow.

Run 1

Code Structure: Methods are logically grouped with section headings, helper functions, and consistent public/private boundaries, although the class is very large. Nesting: Most methods use manageable branching and early returns, but bulk operations contain deeply nested loops and exception handling. Clarity of intent: Descriptive method names, docstrings, and explanatory comments clarify database behavior; generic iterator names and repeated dynamic builtins imports obscure straightforward iteration. Code length: Many simple for-loops are unnecessarily expanded into iterator setup, while True, next(), and StopIteration handling, substantially increasing length and repetition. Action granularity: Statements generally perform one action per line, with readable multiline calls; some comprehensions and conditional expressions are denser. Reading flow: Consistent formatting and synchronous/asynchronous method pairing aid navigation, but verbose manual iteration repeatedly interrupts the business logic. Overall, the organization and documentation preserve readability despite significant avoidable verbosity and nesting.

Run 2

Code Structure: Methods are logically grouped with section headings, and helper methods separate many responsibilities, although the class is large. Nesting: Most methods use manageable branching, but bulk operations contain deeply nested loops and exception handling. Clarity of intent: Descriptive method names, docstrings, and explanatory comments clarify database behavior; opaque iterator names and repeated dynamic builtins imports obscure otherwise simple iteration. Code length: Much complexity is justified by ORM requirements, but manually expanded while/try/StopIteration loops add substantial unnecessary length compared with for loops. Action granularity: Statements generally perform one action per line, with occasional compact assignments and complex expressions. Reading flow: Consistent formatting, guard clauses, and predictable synchronous/asynchronous pairs help navigation, but repetitive iterator boilerplate interrupts the flow and makes core logic harder to identify.

Run 3

Code Structure: Clearly grouped methods, section headings, and helper functions provide logical organization, although the class is very large. Nesting: Most methods use manageable conditionals and early returns, but bulk operations contain deeply nested loops and exception handling. Clarity of intent: Descriptive method names, docstrings, and explanatory comments communicate database behavior well; opaque names such as loopIteratorAD and repeated dynamic builtins imports obscure simple iteration. Code length: Many ordinary for-loops are unnecessarily expanded into iterator initialization, while True, next(), and StopIteration handling, substantially inflating the code. Action granularity: Statements generally perform one action per line, with some dense comprehensions and chained calls. Reading flow: Consistent formatting and predictable synchronous/asynchronous method pairs help navigation, but repetitive iteration boilerplate interrupts the business logic and makes complex methods harder to follow.