telemeta.models.core module
# -*- coding: utf-8 -*- # # Copyright (C) 2007-2010 Samalyse SARL # Copyright (C) 2010-2011 Parisson SARL # # This file is part of Telemeta. # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Affero General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU Affero General Public License for more details. # You should have received a copy of the GNU Affero General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. # # Authors: Olivier Guilyardi <olivier@samalyse.com> # Guillaume Pellerin <yomguy@parisson.com> import datetime import mimetypes import re, os, random from django import forms from django.conf import settings from django.contrib.auth.models import User from django.contrib.sites.models import Site from django.core import exceptions from django.core.exceptions import ObjectDoesNotExist, ValidationError from django.core.urlresolvers import reverse, reverse_lazy from django.db import models from django.db.models import Q, URLField from django.db.models.fields import FieldDoesNotExist from django.forms.models import model_to_dict from django.utils.translation import ugettext from django.utils.translation import ugettext_lazy as _ from telemeta.models.utils import * from telemeta.models.fields import * from telemeta.util.kdenlive_session import * from telemeta.util.unaccent import unaccent_icmp from xml.dom.minidom import getDOMImplementation from dirtyfields import DirtyFieldsMixin PUBLIC_ACCESS_CHOICES = (('none', _('none')), ('metadata', _('metadata')), ('mixed', _('mixed')), ('full', _('full'))) public_extra_types = { '.webm': 'video/webm', '.mp4': 'video/mp4', } private_extra_types = { '.eaf': 'text/xml', # ELAN Annotation Format '.trs': 'text/xml', # Trancriber Annotation Format '.svl': 'text/xml', # Sonic Visualiser layer file '.TextGrid': 'text/praat-textgrid', # Praat TextGrid annotation file } for ext,mime_type in public_extra_types.items(): mimetypes.add_type(mime_type, ext) for ext,mime_type in private_extra_types.items(): mimetypes.add_type(mime_type, ext) app_name = 'telemeta' strict_code = getattr(settings, 'TELEMETA_STRICT_CODE', False) class EnhancedQuerySet(models.query.QuerySet): """QuerySet with added functionalities such as WeakForeignKey handling""" def delete(self): CHUNK=1024 objects = self.model._meta.get_all_related_objects() ii = self.count() values = self.values_list('pk') for related in objects: i = 0 while i < ii: ids = [v[0] for v in values[i:i + CHUNK]] filter = {related.field.name + '__pk__in': ids} q = related.model.objects.filter(**filter) if isinstance(related.field, WeakForeignKey): update = {related.field.name: None} q.update(**update) else: q.delete() i += CHUNK super(EnhancedQuerySet, self).delete() class EnhancedManager(models.Manager): """Manager which is bound to EnhancedQuerySet""" def get_query_set(self): return EnhancedQuerySet(self.model) class EnhancedModel(models.Model): """Base model class with added functionality. See EnhancedQuerySet""" objects = EnhancedManager() def delete(self): if not self.pk: raise Exception("Can't delete without a primary key") self.__class__.objects.filter(pk=self.pk).delete() class Meta: abstract = True class ModelCore(EnhancedModel, DirtyFieldsMixin): @classmethod def required_fields(cls): required = [] for field in cls._meta.fields: if not field.blank: required.append(field) return required def save(self, force_insert=False, force_update=False, *args, **kwargs): required = self.required_fields() for field in required: if not getattr(self, field.name): raise RequiredFieldError(self, field) super(ModelCore, self).save(force_insert, force_update, *args, **kwargs) @classmethod def get_dom_name(cls): "Convert the class name to a DOM element name" clsname = cls.__name__ return clsname[0].lower() + clsname[1:] @staticmethod def get_dom_field_name(field_name): "Convert the class name to a DOM element name" tokens = field_name.split('_') name = tokens[0] for t in tokens[1:]: name += t[0].upper() + t[1:] return name def to_dom(self): "Return the DOM representation of this media object" impl = getDOMImplementation() root = self.get_dom_name() doc = impl.createDocument(None, root, None) top = doc.documentElement top.setAttribute("id", str(self.pk)) fields = self.to_dict() for name, value in fields.iteritems(): element = doc.createElement(self.get_dom_field_name(name)) if isinstance(value, EnhancedModel): element.setAttribute('key', str(value.pk)) value = unicode(value) element.appendChild(doc.createTextNode(value)) top.appendChild(element) return doc def to_dict(self): "Return model fields as a dict of name/value pairs" fields_dict = {} for field in self._meta.fields: fields_dict[field.name] = getattr(self, field.name) return fields_dict def to_list(self): "Return model fields as a list" fields_list = [] for field in self._meta.fields: fields_list.append({'name': field.name, 'value': unicode(getattr(self, field.name))}) return fields_list @classmethod def field_label(cls, field_name=None): if field_name: try: return cls._meta.get_field(field_name).verbose_name except FieldDoesNotExist: try: return getattr(cls, field_name).verbose_name except AttributeError: return field_name else: return cls._meta.verbose_name class Meta: abstract = True class MetaCore: app_label = 'telemeta' class CoreQuerySet(EnhancedQuerySet): "Base class for all query sets" def none(self): # redundant with none() in recent Django svn "Return an empty result set" return self.extra(where = ["0 = 1"]) def word_search(self, field, pattern): return self.filter(word_search_q(field, pattern)) def _by_change_time(self, type, from_time = None, until_time = None): "Search between two revision dates" table = self.model._meta.db_table where = [] if from_time: where.append("revisions.time >= '%s'" % from_time.strftime('%Y-%m-%d %H:%M:%S')) if until_time: where.append("revisions.time <= '%s'" % until_time.strftime('%Y-%m-%d %H:%M:%S')) qs = self if where: where.extend(["revisions.element_type = '%s'" % type, "revisions.element_id = %s.id" % table]) qs = qs.extra(where = [" AND ".join(where)], tables = ['revisions']).distinct() return qs class CoreManager(EnhancedManager): "Base class for all models managers" def none(self, *args, **kwargs): "" return self.get_query_set().none(*args, **kwargs) def get(self, **kwargs): if kwargs.has_key('public_id'): try: args = kwargs.copy() args['code'] = kwargs['public_id'] args.pop('public_id') return super(CoreManager, self).get(**args) except ObjectDoesNotExist: args = kwargs.copy() args['id'] = kwargs['public_id'] args.pop('public_id') return super(CoreManager, self).get(**args) return super(CoreManager, self).get(**kwargs)
Module variables
var PUBLIC_ACCESS_CHOICES
var app_name
var code_linesep
var default_decoding
var default_encoding
var eol
var ext
var mime_type
var private_extra_types
var public_extra_types
var strict_code
Classes
class CoreManager
Base class for all models managers
class CoreManager(EnhancedManager): "Base class for all models managers" def none(self, *args, **kwargs): "" return self.get_query_set().none(*args, **kwargs) def get(self, **kwargs): if kwargs.has_key('public_id'): try: args = kwargs.copy() args['code'] = kwargs['public_id'] args.pop('public_id') return super(CoreManager, self).get(**args) except ObjectDoesNotExist: args = kwargs.copy() args['id'] = kwargs['public_id'] args.pop('public_id') return super(CoreManager, self).get(**args) return super(CoreManager, self).get(**kwargs)
Ancestors (in MRO)
- CoreManager
- EnhancedManager
- django.db.models.manager.Manager
- __builtin__.object
Class variables
Instance variables
Methods
def __init__(
self)
Inheritance:
EnhancedManager
.__init__
def __init__(self): super(Manager, self).__init__() self._set_creation_counter() self.model = None self._inherited = False self._db = None
def aggregate(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.aggregate
def aggregate(self, *args, **kwargs): return self.get_queryset().aggregate(*args, **kwargs)
def annotate(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.annotate
def annotate(self, *args, **kwargs): return self.get_queryset().annotate(*args, **kwargs)
def bulk_create(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.bulk_create
def bulk_create(self, *args, **kwargs): return self.get_queryset().bulk_create(*args, **kwargs)
def complex_filter(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.complex_filter
def complex_filter(self, *args, **kwargs): return self.get_queryset().complex_filter(*args, **kwargs)
def contribute_to_class(
self, model, name)
Inheritance:
EnhancedManager
.contribute_to_class
def contribute_to_class(self, model, name): # TODO: Use weakref because of possible memory leak / circular reference. self.model = model # Only contribute the manager if the model is concrete if model._meta.abstract: setattr(model, name, AbstractManagerDescriptor(model)) elif model._meta.swapped: setattr(model, name, SwappedManagerDescriptor(model)) else: # if not model._meta.abstract and not model._meta.swapped: setattr(model, name, ManagerDescriptor(self)) if not getattr(model, '_default_manager', None) or self.creation_counter < model._default_manager.creation_counter: model._default_manager = self if model._meta.abstract or (self._inherited and not self.model._meta.proxy): model._meta.abstract_managers.append((self.creation_counter, name, self)) else: model._meta.concrete_managers.append((self.creation_counter, name, self))
def count(
self)
Inheritance:
EnhancedManager
.count
def count(self): return self.get_queryset().count()
def create(
self, **kwargs)
Inheritance:
EnhancedManager
.create
def create(self, **kwargs): return self.get_queryset().create(**kwargs)
def dates(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.dates
def dates(self, *args, **kwargs): return self.get_queryset().dates(*args, **kwargs)
def datetimes(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.datetimes
def datetimes(self, *args, **kwargs): return self.get_queryset().datetimes(*args, **kwargs)
def db_manager(
self, using)
Inheritance:
EnhancedManager
.db_manager
def db_manager(self, using): obj = copy.copy(self) obj._db = using return obj
def defer(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.defer
def defer(self, *args, **kwargs): return self.get_queryset().defer(*args, **kwargs)
def distinct(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.distinct
def distinct(self, *args, **kwargs): return self.get_queryset().distinct(*args, **kwargs)
def earliest(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.earliest
def earliest(self, *args, **kwargs): return self.get_queryset().earliest(*args, **kwargs)
def exclude(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.exclude
def exclude(self, *args, **kwargs): return self.get_queryset().exclude(*args, **kwargs)
def exists(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.exists
def exists(self, *args, **kwargs): return self.get_queryset().exists(*args, **kwargs)
def extra(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.extra
def extra(self, *args, **kwargs): return self.get_queryset().extra(*args, **kwargs)
def filter(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.filter
def filter(self, *args, **kwargs): return self.get_queryset().filter(*args, **kwargs)
def first(
self)
Inheritance:
EnhancedManager
.first
def first(self): return self.get_queryset().first()
def get(
self, **kwargs)
Inheritance:
EnhancedManager
.get
def get(self, **kwargs): if kwargs.has_key('public_id'): try: args = kwargs.copy() args['code'] = kwargs['public_id'] args.pop('public_id') return super(CoreManager, self).get(**args) except ObjectDoesNotExist: args = kwargs.copy() args['id'] = kwargs['public_id'] args.pop('public_id') return super(CoreManager, self).get(**args) return super(CoreManager, self).get(**kwargs)
def get_or_create(
self, **kwargs)
Inheritance:
EnhancedManager
.get_or_create
def get_or_create(self, **kwargs): return self.get_queryset().get_or_create(**kwargs)
def get_query_set(
*args, **kwargs)
Inheritance:
EnhancedManager
.get_query_set
def wrapped(*args, **kwargs): warnings.warn( "`%s.%s` is deprecated, use `%s` instead." % (self.class_name, self.old_method_name, self.new_method_name), self.deprecation_warning, 2) return f(*args, **kwargs)
def get_queryset(
self)
Inheritance:
EnhancedManager
.get_queryset
def get_query_set(self): return EnhancedQuerySet(self.model)
def in_bulk(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.in_bulk
def in_bulk(self, *args, **kwargs): return self.get_queryset().in_bulk(*args, **kwargs)
def iterator(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.iterator
def iterator(self, *args, **kwargs): return self.get_queryset().iterator(*args, **kwargs)
def latest(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.latest
def latest(self, *args, **kwargs): return self.get_queryset().latest(*args, **kwargs)
def none(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.none
def none(self, *args, **kwargs): "" return self.get_query_set().none(*args, **kwargs)
def only(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.only
def only(self, *args, **kwargs): return self.get_queryset().only(*args, **kwargs)
def order_by(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.order_by
def order_by(self, *args, **kwargs): return self.get_queryset().order_by(*args, **kwargs)
Inheritance:
EnhancedManager
.prefetch_related
def raw(
self, raw_query, params=None, *args, **kwargs)
Inheritance:
EnhancedManager
.raw
def raw(self, raw_query, params=None, *args, **kwargs): return RawQuerySet(raw_query=raw_query, model=self.model, params=params, using=self._db, *args, **kwargs)
def reverse(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.reverse
def reverse(self, *args, **kwargs): return self.get_queryset().reverse(*args, **kwargs)
def select_for_update(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.select_for_update
def select_for_update(self, *args, **kwargs): return self.get_queryset().select_for_update(*args, **kwargs)
Inheritance:
EnhancedManager
.select_related
def update(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.update
def update(self, *args, **kwargs): return self.get_queryset().update(*args, **kwargs)
def using(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.using
def using(self, *args, **kwargs): return self.get_queryset().using(*args, **kwargs)
def values(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.values
def values(self, *args, **kwargs): return self.get_queryset().values(*args, **kwargs)
def values_list(
self, *args, **kwargs)
Inheritance:
EnhancedManager
.values_list
def values_list(self, *args, **kwargs): return self.get_queryset().values_list(*args, **kwargs)
class CoreQuerySet
Base class for all query sets
class CoreQuerySet(EnhancedQuerySet): "Base class for all query sets" def none(self): # redundant with none() in recent Django svn "Return an empty result set" return self.extra(where = ["0 = 1"]) def word_search(self, field, pattern): return self.filter(word_search_q(field, pattern)) def _by_change_time(self, type, from_time = None, until_time = None): "Search between two revision dates" table = self.model._meta.db_table where = [] if from_time: where.append("revisions.time >= '%s'" % from_time.strftime('%Y-%m-%d %H:%M:%S')) if until_time: where.append("revisions.time <= '%s'" % until_time.strftime('%Y-%m-%d %H:%M:%S')) qs = self if where: where.extend(["revisions.element_type = '%s'" % type, "revisions.element_id = %s.id" % table]) qs = qs.extra(where = [" AND ".join(where)], tables = ['revisions']).distinct() return qs
Ancestors (in MRO)
- CoreQuerySet
- EnhancedQuerySet
- django.db.models.query.QuerySet
- __builtin__.object
Class variables
Instance variables
var db
Inheritance:
EnhancedQuerySet
.db
Return the database that will be used if this query is executed now
var ordered
Inheritance:
EnhancedQuerySet
.ordered
Returns True if the QuerySet is ordered -- i.e. has an order_by() clause or a default ordering on the model.
Methods
def __init__(
self, model=None, query=None, using=None)
Inheritance:
EnhancedQuerySet
.__init__
def __init__(self, model=None, query=None, using=None): self.model = model self._db = using 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}}
def aggregate(
self, *args, **kwargs)
Inheritance:
EnhancedQuerySet
.aggregate
Returns 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.
def aggregate(self, *args, **kwargs): """ Returns 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.") for arg in args: kwargs[arg.default_alias] = arg query = self.query.clone() for (alias, aggregate_expr) in kwargs.items(): query.add_aggregate(aggregate_expr, self.model, alias, is_summary=True) return query.get_aggregation(using=self.db)
def all(
self)
Inheritance:
EnhancedQuerySet
.all
Returns a new QuerySet that is a copy of the current one. This allows a QuerySet to proxy for a model manager in some cases.
def all(self): """ Returns 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._clone()
def annotate(
self, *args, **kwargs)
Inheritance:
EnhancedQuerySet
.annotate
Return a query set in which the returned objects have been annotated with data aggregated from related fields.
def annotate(self, *args, **kwargs): """ Return a query set in which the returned objects have been annotated with data aggregated from related fields. """ for arg in args: if arg.default_alias in kwargs: raise ValueError("The named annotation '%s' conflicts with the " "default name for another annotation." % arg.default_alias) kwargs[arg.default_alias] = arg names = getattr(self, '_fields', None) if names is None: names = set(self.model._meta.get_all_field_names()) for aggregate in kwargs: if aggregate in names: raise ValueError("The annotation '%s' conflicts with a field on " "the model." % aggregate) obj = self._clone() obj._setup_aggregate_query(list(kwargs)) # Add the aggregates to the query for (alias, aggregate_expr) in kwargs.items(): obj.query.add_aggregate(aggregate_expr, self.model, alias, is_summary=False) return obj
def bulk_create(
self, objs, batch_size=None)
Inheritance:
EnhancedQuerySet
.bulk_create
Inserts each of the instances into the database. This does not call save() on each of the instances, does not send any pre/post save signals, and does not set the primary key attribute if it is an autoincrement field.
def bulk_create(self, objs, batch_size=None): """ Inserts each of the instances into the database. This does *not* call save() on each of the instances, does not send any pre/post save signals, and does not set the primary key attribute if it is an autoincrement field. """ # So this case is fun. When you bulk insert you don't get the primary # keys back (if it's an autoincrement), 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, # and 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. Some databases might allow doing # this by using RETURNING clause for the insert query. We're punting # on these for now because they are relatively rare cases. assert batch_size is None or batch_size > 0 if self.model._meta.parents: raise ValueError("Can't bulk create an inherited model") if not objs: return objs self._for_write = True connection = connections[self.db] fields = self.model._meta.local_concrete_fields with transaction.commit_on_success_unless_managed(using=self.db): if (connection.features.can_combine_inserts_with_and_without_auto_increment_pk and self.model._meta.has_auto_field): self._batched_insert(objs, fields, batch_size) else: objs_with_pk, objs_without_pk = partition(lambda o: o.pk is None, objs) if objs_with_pk: self._batched_insert(objs_with_pk, fields, batch_size) if objs_without_pk: fields= [f for f in fields if not isinstance(f, AutoField)] self._batched_insert(objs_without_pk, fields, batch_size) return objs
def complex_filter(
self, filter_obj)
Inheritance:
EnhancedQuerySet
.complex_filter
Returns a new QuerySet instance with filter_obj added to the filters.
filter_obj can be a Q object (or anything with an add_to_query() method) 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.
def complex_filter(self, filter_obj): """ Returns a new QuerySet instance with filter_obj added to the filters. filter_obj can be a Q object (or anything with an add_to_query() method) 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) or hasattr(filter_obj, 'add_to_query'): clone = self._clone() clone.query.add_q(filter_obj) return clone else: return self._filter_or_exclude(None, **filter_obj)
def count(
self)
Inheritance:
EnhancedQuerySet
.count
Performs a SELECT COUNT() and returns the number of records as an integer.
If the QuerySet is already fully cached this simply returns the length of the cached results set to avoid multiple SELECT COUNT(*) calls.
def count(self): """ Performs a SELECT COUNT() and returns the number of records as an integer. If the QuerySet is already fully cached this simply returns 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)
def create(
self, **kwargs)
Inheritance:
EnhancedQuerySet
.create
Creates a new object with the given kwargs, saving it to the database and returning the created object.
def create(self, **kwargs): """ Creates a new object with the given kwargs, saving it to the database and returning the created object. """ obj = self.model(**kwargs) self._for_write = True obj.save(force_insert=True, using=self.db) return obj
def dates(
self, field_name, kind, order='ASC')
Inheritance:
EnhancedQuerySet
.dates
Returns a list of date objects representing all available dates for the given field_name, scoped to 'kind'.
def dates(self, field_name, kind, order='ASC'): """ Returns a list of date objects representing all available dates for the given field_name, scoped to 'kind'. """ assert kind in ("year", "month", "day"), \ "'kind' must be one of 'year', 'month' or 'day'." assert order in ('ASC', 'DESC'), \ "'order' must be either 'ASC' or 'DESC'." return self._clone(klass=DateQuerySet, setup=True, _field_name=field_name, _kind=kind, _order=order)
def datetimes(
self, field_name, kind, order='ASC', tzinfo=None)
Inheritance:
EnhancedQuerySet
.datetimes
Returns a list of datetime objects representing all available datetimes for the given field_name, scoped to 'kind'.
def datetimes(self, field_name, kind, order='ASC', tzinfo=None): """ Returns a list of datetime objects representing all available datetimes for the given field_name, scoped to 'kind'. """ assert kind in ("year", "month", "day", "hour", "minute", "second"), \ "'kind' must be one of 'year', 'month', 'day', 'hour', 'minute' or 'second'." assert order in ('ASC', 'DESC'), \ "'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._clone(klass=DateTimeQuerySet, setup=True, _field_name=field_name, _kind=kind, _order=order, _tzinfo=tzinfo)
def defer(
self, *fields)
Inheritance:
EnhancedQuerySet
.defer
Defers the loading of data for certain fields until they are accessed. The set of fields to defer is added 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 all deferrals are removed (None acts as a reset option).
def defer(self, *fields): """ Defers the loading of data for certain fields until they are accessed. The set of fields to defer is added 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 all deferrals are removed (None acts as a reset option). """ clone = self._clone() if fields == (None,): clone.query.clear_deferred_loading() else: clone.query.add_deferred_loading(fields) return clone
def delete(
self)
Inheritance:
EnhancedQuerySet
.delete
def delete(self): CHUNK=1024 objects = self.model._meta.get_all_related_objects() ii = self.count() values = self.values_list('pk') for related in objects: i = 0 while i < ii: ids = [v[0] for v in values[i:i + CHUNK]] filter = {related.field.name + '__pk__in': ids} q = related.model.objects.filter(**filter) if isinstance(related.field, WeakForeignKey): update = {related.field.name: None} q.update(**update) else: q.delete() i += CHUNK super(EnhancedQuerySet, self).delete()
def distinct(
self, *field_names)
Inheritance:
EnhancedQuerySet
.distinct
Returns a new QuerySet instance that will select only distinct results.
def distinct(self, *field_names): """ Returns a new QuerySet instance that will select only distinct results. """ assert self.query.can_filter(), \ "Cannot create distinct fields once a slice has been taken." obj = self._clone() obj.query.add_distinct_fields(*field_names) return obj
def earliest(
self, field_name=None)
Inheritance:
EnhancedQuerySet
.earliest
def earliest(self, field_name=None): return self._earliest_or_latest(field_name=field_name, direction="")
def exclude(
self, *args, **kwargs)
Inheritance:
EnhancedQuerySet
.exclude
Returns a new QuerySet instance with NOT (args) ANDed to the existing set.
def exclude(self, *args, **kwargs): """ Returns a new QuerySet instance with NOT (args) ANDed to the existing set. """ return self._filter_or_exclude(True, *args, **kwargs)
def exists(
self)
Inheritance:
EnhancedQuerySet
.exists
def exists(self): if self._result_cache is None: return self.query.has_results(using=self.db) return bool(self._result_cache)
def extra(
self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None)
Inheritance:
EnhancedQuerySet
.extra
Adds extra SQL fragments to the query.
def extra(self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None): """ Adds extra SQL fragments to the query. """ assert self.query.can_filter(), \ "Cannot change a query once a slice has been taken" clone = self._clone() clone.query.add_extra(select, select_params, where, params, tables, order_by) return clone
def filter(
self, *args, **kwargs)
Inheritance:
EnhancedQuerySet
.filter
Returns a new QuerySet instance with the args ANDed to the existing set.
def filter(self, *args, **kwargs): """ Returns a new QuerySet instance with the args ANDed to the existing set. """ return self._filter_or_exclude(False, *args, **kwargs)
def first(
self)
Inheritance:
EnhancedQuerySet
.first
Returns the first object of a query, returns None if no match is found.
def first(self): """ Returns the first object of a query, returns None if no match is found. """ qs = self if self.ordered else self.order_by('pk') try: return qs[0] except IndexError: return None
def get(
self, *args, **kwargs)
Inheritance:
EnhancedQuerySet
.get
Performs the query and returns a single object matching the given keyword arguments.
def get(self, *args, **kwargs): """ Performs the query and returns a single object matching the given keyword arguments. """ clone = self.filter(*args, **kwargs) if self.query.can_filter(): clone = clone.order_by() 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))
def get_or_create(
self, **kwargs)
Inheritance:
EnhancedQuerySet
.get_or_create
Looks up an object with the given kwargs, creating one if necessary. Returns a tuple of (object, created), where created is a boolean specifying whether an object was created.
def get_or_create(self, **kwargs): """ Looks up an object with the given kwargs, creating one if necessary. Returns a tuple of (object, created), where created is a boolean specifying whether an object was created. """ defaults = kwargs.pop('defaults', {}) lookup = kwargs.copy() for f in self.model._meta.fields: if f.attname in lookup: lookup[f.name] = lookup.pop(f.attname) try: self._for_write = True return self.get(**lookup), False except self.model.DoesNotExist: try: params = dict((k, v) for k, v in kwargs.items() if LOOKUP_SEP not in k) params.update(defaults) obj = self.model(**params) with transaction.atomic(using=self.db): obj.save(force_insert=True, using=self.db) return obj, True except DatabaseError: exc_info = sys.exc_info() try: return self.get(**lookup), False except self.model.DoesNotExist: # Re-raise the DatabaseError with its original traceback. six.reraise(*exc_info)
def in_bulk(
self, id_list)
Inheritance:
EnhancedQuerySet
.in_bulk
Returns a dictionary mapping each of the given IDs to the object with that ID.
def in_bulk(self, id_list): """ Returns a dictionary mapping each of the given IDs to the object with that ID. """ assert self.query.can_filter(), \ "Cannot use 'limit' or 'offset' with in_bulk" if not id_list: return {} qs = self.filter(pk__in=id_list).order_by() return dict([(obj._get_pk_val(), obj) for obj in qs])
def iterator(
self)
Inheritance:
EnhancedQuerySet
.iterator
An iterator over the results from applying this QuerySet to the database.
def iterator(self): """ An iterator over the results from applying this QuerySet to the database. """ fill_cache = False if connections[self.db].features.supports_select_related: fill_cache = self.query.select_related if isinstance(fill_cache, dict): requested = fill_cache else: requested = None max_depth = self.query.max_depth extra_select = list(self.query.extra_select) aggregate_select = list(self.query.aggregate_select) only_load = self.query.get_loaded_field_names() if not fill_cache: fields = self.model._meta.concrete_fields load_fields = [] # If only/defer clauses have been specified, # build the list of fields that are to be loaded. if only_load: for field, model in self.model._meta.get_concrete_fields_with_model(): if model is None: model = self.model try: if field.name in only_load[model]: # Add a field that has been explicitly included load_fields.append(field.name) except KeyError: # Model wasn't explicitly listed in the only_load table # Therefore, we need to load all fields from this model load_fields.append(field.name) index_start = len(extra_select) aggregate_start = index_start + len(load_fields or self.model._meta.concrete_fields) skip = None if load_fields and not fill_cache: # Some fields have been deferred, so we have to initialise # via keyword arguments. skip = set() init_list = [] for field in fields: if field.name not in load_fields: skip.add(field.attname) else: init_list.append(field.attname) model_cls = deferred_class_factory(self.model, skip) # Cache db and model outside the loop db = self.db model = self.model compiler = self.query.get_compiler(using=db) if fill_cache: klass_info = get_klass_info(model, max_depth=max_depth, requested=requested, only_load=only_load) for row in compiler.results_iter(): if fill_cache: obj, _ = get_cached_row(row, index_start, db, klass_info, offset=len(aggregate_select)) else: # Omit aggregates in object creation. row_data = row[index_start:aggregate_start] if skip: obj = model_cls(**dict(zip(init_list, row_data))) else: obj = model(*row_data) # Store the source database of the object obj._state.db = db # This object came from the database; it's not being added. obj._state.adding = False if extra_select: for i, k in enumerate(extra_select): setattr(obj, k, row[i]) # Add the aggregates to the model if aggregate_select: for i, aggregate in enumerate(aggregate_select): setattr(obj, aggregate, row[i + aggregate_start]) # Add the known related objects to the model, if there are any if self._known_related_objects: for field, rel_objs in self._known_related_objects.items(): # Avoid overwriting objects loaded e.g. by select_related if hasattr(obj, field.get_cache_name()): continue pk = getattr(obj, field.get_attname()) try: rel_obj = rel_objs[pk] except KeyError: pass # may happen in qs1 | qs2 scenarios else: setattr(obj, field.name, rel_obj) yield obj
def last(
self)
Inheritance:
EnhancedQuerySet
.last
Returns the last object of a query, returns None if no match is found.
def last(self): """ Returns the last object of a query, returns None if no match is found. """ qs = self.reverse() if self.ordered else self.order_by('-pk') try: return qs[0] except IndexError: return None
def latest(
self, field_name=None)
Inheritance:
EnhancedQuerySet
.latest
def latest(self, field_name=None): return self._earliest_or_latest(field_name=field_name, direction="-")
def none(
self)
Inheritance:
EnhancedQuerySet
.none
Return an empty result set
def none(self): # redundant with none() in recent Django svn "Return an empty result set" return self.extra(where = ["0 = 1"])
def only(
self, *fields)
Inheritance:
EnhancedQuerySet
.only
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.
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. """ 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().") clone = self._clone() clone.query.add_immediate_loading(fields) return clone
def order_by(
self, *field_names)
Inheritance:
EnhancedQuerySet
.order_by
Returns a new QuerySet instance with the ordering changed.
def order_by(self, *field_names): """ Returns a new QuerySet instance with the ordering changed. """ assert self.query.can_filter(), \ "Cannot reorder a query once a slice has been taken." obj = self._clone() obj.query.clear_ordering(force_empty=False) obj.query.add_ordering(*field_names) return obj
Inheritance:
EnhancedQuerySet
.prefetch_related
Returns 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, the list of lookups to prefetch is appended to. If prefetch_related(None) is called, the the list is cleared.
def reverse(
self)
Inheritance:
EnhancedQuerySet
.reverse
Reverses the ordering of the QuerySet.
def reverse(self): """ Reverses the ordering of the QuerySet. """ clone = self._clone() clone.query.standard_ordering = not clone.query.standard_ordering return clone
def select_for_update(
self, **kwargs)
Inheritance:
EnhancedQuerySet
.select_for_update
Returns a new QuerySet instance that will select objects with a FOR UPDATE lock.
def select_for_update(self, **kwargs): """ Returns a new QuerySet instance that will select objects with a FOR UPDATE lock. """ # Default to false for nowait nowait = kwargs.pop('nowait', False) obj = self._clone() obj._for_write = True obj.query.select_for_update = True obj.query.select_for_update_nowait = nowait return obj
Inheritance:
EnhancedQuerySet
.select_related
Returns 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, the list is cleared.
def update(
self, **kwargs)
Inheritance:
EnhancedQuerySet
.update
Updates all elements in the current QuerySet, setting all the given fields to the appropriate values.
def update(self, **kwargs): """ Updates all elements in the current QuerySet, setting all the given fields to the appropriate values. """ assert self.query.can_filter(), \ "Cannot update a query once a slice has been taken." self._for_write = True query = self.query.clone(sql.UpdateQuery) query.add_update_values(kwargs) with transaction.commit_on_success_unless_managed(using=self.db): rows = query.get_compiler(self.db).execute_sql(None) self._result_cache = None return rows
def using(
self, alias)
Inheritance:
EnhancedQuerySet
.using
Selects which database this QuerySet should excecute its query against.
def using(self, alias): """ Selects which database this QuerySet should excecute its query against. """ clone = self._clone() clone._db = alias return clone
def values(
self, *fields)
Inheritance:
EnhancedQuerySet
.values
def values(self, *fields): return self._clone(klass=ValuesQuerySet, setup=True, _fields=fields)
def values_list(
self, *fields, **kwargs)
Inheritance:
EnhancedQuerySet
.values_list
def values_list(self, *fields, **kwargs): flat = kwargs.pop('flat', False) if kwargs: raise TypeError('Unexpected keyword arguments to values_list: %s' % (list(kwargs),)) if flat and len(fields) > 1: raise TypeError("'flat' is not valid when values_list is called with more than one field.") return self._clone(klass=ValuesListQuerySet, setup=True, flat=flat, _fields=fields)
def word_search(
self, field, pattern)
def word_search(self, field, pattern): return self.filter(word_search_q(field, pattern))
class EnhancedManager
Manager which is bound to EnhancedQuerySet
class EnhancedManager(models.Manager): """Manager which is bound to EnhancedQuerySet""" def get_query_set(self): return EnhancedQuerySet(self.model)
Ancestors (in MRO)
- EnhancedManager
- django.db.models.manager.Manager
- __builtin__.object
Class variables
var creation_counter
Instance variables
var db
Methods
def __init__(
self)
def __init__(self): super(Manager, self).__init__() self._set_creation_counter() self.model = None self._inherited = False self._db = None
def aggregate(
self, *args, **kwargs)
def aggregate(self, *args, **kwargs): return self.get_queryset().aggregate(*args, **kwargs)
def all(
self)
def all(self): return self.get_queryset()
def annotate(
self, *args, **kwargs)
def annotate(self, *args, **kwargs): return self.get_queryset().annotate(*args, **kwargs)
def bulk_create(
self, *args, **kwargs)
def bulk_create(self, *args, **kwargs): return self.get_queryset().bulk_create(*args, **kwargs)
def complex_filter(
self, *args, **kwargs)
def complex_filter(self, *args, **kwargs): return self.get_queryset().complex_filter(*args, **kwargs)
def contribute_to_class(
self, model, name)
def contribute_to_class(self, model, name): # TODO: Use weakref because of possible memory leak / circular reference. self.model = model # Only contribute the manager if the model is concrete if model._meta.abstract: setattr(model, name, AbstractManagerDescriptor(model)) elif model._meta.swapped: setattr(model, name, SwappedManagerDescriptor(model)) else: # if not model._meta.abstract and not model._meta.swapped: setattr(model, name, ManagerDescriptor(self)) if not getattr(model, '_default_manager', None) or self.creation_counter < model._default_manager.creation_counter: model._default_manager = self if model._meta.abstract or (self._inherited and not self.model._meta.proxy): model._meta.abstract_managers.append((self.creation_counter, name, self)) else: model._meta.concrete_managers.append((self.creation_counter, name, self))
def count(
self)
def count(self): return self.get_queryset().count()
def create(
self, **kwargs)
def create(self, **kwargs): return self.get_queryset().create(**kwargs)
def dates(
self, *args, **kwargs)
def dates(self, *args, **kwargs): return self.get_queryset().dates(*args, **kwargs)
def datetimes(
self, *args, **kwargs)
def datetimes(self, *args, **kwargs): return self.get_queryset().datetimes(*args, **kwargs)
def db_manager(
self, using)
def db_manager(self, using): obj = copy.copy(self) obj._db = using return obj
def defer(
self, *args, **kwargs)
def defer(self, *args, **kwargs): return self.get_queryset().defer(*args, **kwargs)
def distinct(
self, *args, **kwargs)
def distinct(self, *args, **kwargs): return self.get_queryset().distinct(*args, **kwargs)
def earliest(
self, *args, **kwargs)
def earliest(self, *args, **kwargs): return self.get_queryset().earliest(*args, **kwargs)
def exclude(
self, *args, **kwargs)
def exclude(self, *args, **kwargs): return self.get_queryset().exclude(*args, **kwargs)
def exists(
self, *args, **kwargs)
def exists(self, *args, **kwargs): return self.get_queryset().exists(*args, **kwargs)
def extra(
self, *args, **kwargs)
def extra(self, *args, **kwargs): return self.get_queryset().extra(*args, **kwargs)
def filter(
self, *args, **kwargs)
def filter(self, *args, **kwargs): return self.get_queryset().filter(*args, **kwargs)
def first(
self)
def first(self): return self.get_queryset().first()
def get(
self, *args, **kwargs)
def get(self, *args, **kwargs): return self.get_queryset().get(*args, **kwargs)
def get_or_create(
self, **kwargs)
def get_or_create(self, **kwargs): return self.get_queryset().get_or_create(**kwargs)
def get_query_set(
*args, **kwargs)
def wrapped(*args, **kwargs): warnings.warn( "`%s.%s` is deprecated, use `%s` instead." % (self.class_name, self.old_method_name, self.new_method_name), self.deprecation_warning, 2) return f(*args, **kwargs)
def get_queryset(
self)
def get_query_set(self): return EnhancedQuerySet(self.model)
def in_bulk(
self, *args, **kwargs)
def in_bulk(self, *args, **kwargs): return self.get_queryset().in_bulk(*args, **kwargs)
def iterator(
self, *args, **kwargs)
def iterator(self, *args, **kwargs): return self.get_queryset().iterator(*args, **kwargs)
def last(
self)
def last(self): return self.get_queryset().last()
def latest(
self, *args, **kwargs)
def latest(self, *args, **kwargs): return self.get_queryset().latest(*args, **kwargs)
def none(
self)
def none(self): return self.get_queryset().none()
def only(
self, *args, **kwargs)
def only(self, *args, **kwargs): return self.get_queryset().only(*args, **kwargs)
def order_by(
self, *args, **kwargs)
def order_by(self, *args, **kwargs): return self.get_queryset().order_by(*args, **kwargs)
def raw(
self, raw_query, params=None, *args, **kwargs)
def raw(self, raw_query, params=None, *args, **kwargs): return RawQuerySet(raw_query=raw_query, model=self.model, params=params, using=self._db, *args, **kwargs)
def reverse(
self, *args, **kwargs)
def reverse(self, *args, **kwargs): return self.get_queryset().reverse(*args, **kwargs)
def select_for_update(
self, *args, **kwargs)
def select_for_update(self, *args, **kwargs): return self.get_queryset().select_for_update(*args, **kwargs)
def update(
self, *args, **kwargs)
def update(self, *args, **kwargs): return self.get_queryset().update(*args, **kwargs)
def using(
self, *args, **kwargs)
def using(self, *args, **kwargs): return self.get_queryset().using(*args, **kwargs)
def values(
self, *args, **kwargs)
def values(self, *args, **kwargs): return self.get_queryset().values(*args, **kwargs)
def values_list(
self, *args, **kwargs)
def values_list(self, *args, **kwargs): return self.get_queryset().values_list(*args, **kwargs)
class EnhancedModel
Base model class with added functionality. See EnhancedQuerySet
class EnhancedModel(models.Model): """Base model class with added functionality. See EnhancedQuerySet""" objects = EnhancedManager() def delete(self): if not self.pk: raise Exception("Can't delete without a primary key") self.__class__.objects.filter(pk=self.pk).delete() class Meta: abstract = True
Ancestors (in MRO)
- EnhancedModel
- django.db.models.base.Model
- __builtin__.object
Class variables
var Meta
var objects
Instance variables
var pk
Methods
def __init__(
self, *args, **kwargs)
def __init__(self, *args, **kwargs): signals.pre_init.send(sender=self.__class__, args=args, kwargs=kwargs) # Set up the storage for instance state self._state = ModelState() # There is a rather weird disparity here; if kwargs, it's set, then args # overrides it. It should be one or the other; don't duplicate the work # The reason for the kwargs check is that standard iterator passes in by # args, and instantiation for iteration is 33% faster. args_len = len(args) if args_len > len(self._meta.concrete_fields): # Daft, but matches old exception sans the err msg. raise IndexError("Number of args exceeds number of fields") if not kwargs: fields_iter = iter(self._meta.concrete_fields) # The ordering of the zip calls matter - zip throws StopIteration # when an iter throws it. So if the first iter throws it, the second # is *not* consumed. We rely on this, so don't change the order # without changing the logic. for val, field in zip(args, fields_iter): setattr(self, field.attname, val) else: # Slower, kwargs-ready version. fields_iter = iter(self._meta.fields) for val, field in zip(args, fields_iter): setattr(self, field.attname, val) kwargs.pop(field.name, None) # Maintain compatibility with existing calls. if isinstance(field.rel, ManyToOneRel): kwargs.pop(field.attname, None) # Now we're left with the unprocessed fields that *must* come from # keywords, or default. for field in fields_iter: is_related_object = False # This slightly odd construct is so that we can access any # data-descriptor object (DeferredAttribute) without triggering its # __get__ method. if (field.attname not in kwargs and (isinstance(self.__class__.__dict__.get(field.attname), DeferredAttribute) or field.column is None)): # This field will be populated on request. continue if kwargs: if isinstance(field.rel, ForeignObjectRel): try: # Assume object instance was passed in. rel_obj = kwargs.pop(field.name) is_related_object = True except KeyError: try: # Object instance wasn't passed in -- must be an ID. val = kwargs.pop(field.attname) except KeyError: val = field.get_default() else: # Object instance was passed in. Special case: You can # pass in "None" for related objects if it's allowed. if rel_obj is None and field.null: val = None else: try: val = kwargs.pop(field.attname) except KeyError: # This is done with an exception rather than the # default argument on pop because we don't want # get_default() to be evaluated, and then not used. # Refs #12057. val = field.get_default() else: val = field.get_default() if is_related_object: # If we are passed a related instance, set it using the # field.name instead of field.attname (e.g. "user" instead of # "user_id") so that the object gets properly cached (and type # checked) by the RelatedObjectDescriptor. setattr(self, field.name, rel_obj) else: setattr(self, field.attname, val) if kwargs: for prop in list(kwargs): try: if isinstance(getattr(self.__class__, prop), property): setattr(self, prop, kwargs.pop(prop)) except AttributeError: pass if kwargs: raise TypeError("'%s' is an invalid keyword argument for this function" % list(kwargs)[0]) super(Model, self).__init__() signals.post_init.send(sender=self.__class__, instance=self)
def clean(
self)
Hook for doing any extra model-wide validation after clean() has been called on every field by self.clean_fields. Any ValidationError raised by this method will not be associated with a particular field; it will have a special-case association with the field defined by NON_FIELD_ERRORS.
def clean(self): """ Hook for doing any extra model-wide validation after clean() has been called on every field by self.clean_fields. Any ValidationError raised by this method will not be associated with a particular field; it will have a special-case association with the field defined by NON_FIELD_ERRORS. """ pass
def clean_fields(
self, exclude=None)
Cleans all fields and raises a ValidationError containing message_dict of all validation errors if any occur.
def clean_fields(self, exclude=None): """ Cleans all fields and raises a ValidationError containing message_dict of all validation errors if any occur. """ if exclude is None: exclude = [] errors = {} for f in self._meta.fields: if f.name in exclude: continue # Skip validation for empty fields with blank=True. The developer # is responsible for making sure they have a valid value. raw_value = getattr(self, f.attname) if f.blank and raw_value in f.empty_values: continue try: setattr(self, f.attname, f.clean(raw_value, self)) except ValidationError as e: errors[f.name] = e.error_list if errors: raise ValidationError(errors)
def date_error_message(
self, lookup_type, field, unique_for)
def date_error_message(self, lookup_type, field, unique_for): opts = self._meta return _("%(field_name)s must be unique for %(date_field)s %(lookup)s.") % { 'field_name': six.text_type(capfirst(opts.get_field(field).verbose_name)), 'date_field': six.text_type(capfirst(opts.get_field(unique_for).verbose_name)), 'lookup': lookup_type, }
def delete(
self)
def delete(self): if not self.pk: raise Exception("Can't delete without a primary key") self.__class__.objects.filter(pk=self.pk).delete()
def full_clean(
self, exclude=None, validate_unique=True)
Calls clean_fields, clean, and validate_unique, on the model,
and raises a ValidationError
for any errors that occurred.
def full_clean(self, exclude=None, validate_unique=True): """ Calls clean_fields, clean, and validate_unique, on the model, and raises a ``ValidationError`` for any errors that occurred. """ errors = {} if exclude is None: exclude = [] try: self.clean_fields(exclude=exclude) except ValidationError as e: errors = e.update_error_dict(errors) # Form.clean() is run even if other validation fails, so do the # same with Model.clean() for consistency. try: self.clean() except ValidationError as e: errors = e.update_error_dict(errors) # Run unique checks, but only for fields that passed validation. if validate_unique: for name in errors.keys(): if name != NON_FIELD_ERRORS and name not in exclude: exclude.append(name) try: self.validate_unique(exclude=exclude) except ValidationError as e: errors = e.update_error_dict(errors) if errors: raise ValidationError(errors)
def prepare_database_save(
self, unused)
def prepare_database_save(self, unused): if self.pk is None: raise ValueError("Unsaved model instance %r cannot be used in an ORM query." % self) return self.pk
def save(
self, force_insert=False, force_update=False, using=None, update_fields=None)
Saves the current instance. Override this in a subclass if you want to control the saving process.
The 'force_insert' and 'force_update' parameters can be used to insist that the "save" must be an SQL insert or update (or equivalent for non-SQL backends), respectively. Normally, they should not be set.
def save(self, force_insert=False, force_update=False, using=None, update_fields=None): """ Saves the current instance. Override this in a subclass if you want to control the saving process. The 'force_insert' and 'force_update' parameters can be used to insist that the "save" must be an SQL insert or update (or equivalent for non-SQL backends), respectively. Normally, they should not be set. """ using = using or router.db_for_write(self.__class__, instance=self) if force_insert and (force_update or update_fields): raise ValueError("Cannot force both insert and updating in model saving.") if update_fields is not None: # If update_fields is empty, skip the save. We do also check for # no-op saves later on for inheritance cases. This bailout is # still needed for skipping signal sending. if len(update_fields) == 0: return update_fields = frozenset(update_fields) field_names = set() for field in self._meta.fields: if not field.primary_key: field_names.add(field.name) if field.name != field.attname: field_names.add(field.attname) non_model_fields = update_fields.difference(field_names) if non_model_fields: raise ValueError("The following fields do not exist in this " "model or are m2m fields: %s" % ', '.join(non_model_fields)) # If saving to the same database, and this model is deferred, then # automatically do a "update_fields" save on the loaded fields. elif not force_insert and self._deferred and using == self._state.db: field_names = set() for field in self._meta.concrete_fields: if not field.primary_key and not hasattr(field, 'through'): field_names.add(field.attname) deferred_fields = [ f.attname for f in self._meta.fields if f.attname not in self.__dict__ and isinstance(self.__class__.__dict__[f.attname], DeferredAttribute)] loaded_fields = field_names.difference(deferred_fields) if loaded_fields: update_fields = frozenset(loaded_fields) self.save_base(using=using, force_insert=force_insert, force_update=force_update, update_fields=update_fields)
def save_base(
self, raw=False, force_insert=False, force_update=False, using=None, update_fields=None)
Handles the parts of saving which should be done only once per save, yet need to be done in raw saves, too. This includes some sanity checks and signal sending.
The 'raw' argument is telling save_base not to save any parent models and not to do any changes to the values before save. This is used by fixture loading.
def save_base(self, raw=False, force_insert=False, force_update=False, using=None, update_fields=None): """ Handles the parts of saving which should be done only once per save, yet need to be done in raw saves, too. This includes some sanity checks and signal sending. The 'raw' argument is telling save_base not to save any parent models and not to do any changes to the values before save. This is used by fixture loading. """ using = using or router.db_for_write(self.__class__, instance=self) assert not (force_insert and (force_update or update_fields)) assert update_fields is None or len(update_fields) > 0 cls = origin = self.__class__ # Skip proxies, but keep the origin as the proxy model. if cls._meta.proxy: cls = cls._meta.concrete_model meta = cls._meta if not meta.auto_created: signals.pre_save.send(sender=origin, instance=self, raw=raw, using=using, update_fields=update_fields) with transaction.commit_on_success_unless_managed(using=using, savepoint=False): if not raw: self._save_parents(cls, using, update_fields) updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields) # Store the database on which the object was saved self._state.db = using # Once saved, this is no longer a to-be-added instance. self._state.adding = False # Signal that the save is complete if not meta.auto_created: signals.post_save.send(sender=origin, instance=self, created=(not updated), update_fields=update_fields, raw=raw, using=using)
def serializable_value(
self, field_name)
Returns the value of the field name for this instance. If the field is a foreign key, returns the id value, instead of the object. If there's no Field object with this name on the model, the model attribute's value is returned directly.
Used to serialize a field's value (in the serializer, or form output, for example). Normally, you would just access the attribute directly and not use this method.
def serializable_value(self, field_name): """ Returns the value of the field name for this instance. If the field is a foreign key, returns the id value, instead of the object. If there's no Field object with this name on the model, the model attribute's value is returned directly. Used to serialize a field's value (in the serializer, or form output, for example). Normally, you would just access the attribute directly and not use this method. """ try: field = self._meta.get_field_by_name(field_name)[0] except FieldDoesNotExist: return getattr(self, field_name) return getattr(self, field.attname)
def unique_error_message(
self, model_class, unique_check)
def unique_error_message(self, model_class, unique_check): opts = model_class._meta model_name = capfirst(opts.verbose_name) # A unique field if len(unique_check) == 1: field_name = unique_check[0] field = opts.get_field(field_name) field_label = capfirst(field.verbose_name) # Insert the error into the error dict, very sneaky return field.error_messages['unique'] % { 'model_name': six.text_type(model_name), 'field_label': six.text_type(field_label) } # unique_together else: field_labels = [capfirst(opts.get_field(f).verbose_name) for f in unique_check] field_labels = get_text_list(field_labels, _('and')) return _("%(model_name)s with this %(field_label)s already exists.") % { 'model_name': six.text_type(model_name), 'field_label': six.text_type(field_labels) }
def validate_unique(
self, exclude=None)
Checks unique constraints on the model and raises ValidationError
if any failed.
def validate_unique(self, exclude=None): """ Checks unique constraints on the model and raises ``ValidationError`` if any failed. """ unique_checks, date_checks = self._get_unique_checks(exclude=exclude) errors = self._perform_unique_checks(unique_checks) date_errors = self._perform_date_checks(date_checks) for k, v in date_errors.items(): errors.setdefault(k, []).extend(v) if errors: raise ValidationError(errors)
class EnhancedQuerySet
QuerySet with added functionalities such as WeakForeignKey handling
class EnhancedQuerySet(models.query.QuerySet): """QuerySet with added functionalities such as WeakForeignKey handling""" def delete(self): CHUNK=1024 objects = self.model._meta.get_all_related_objects() ii = self.count() values = self.values_list('pk') for related in objects: i = 0 while i < ii: ids = [v[0] for v in values[i:i + CHUNK]] filter = {related.field.name + '__pk__in': ids} q = related.model.objects.filter(**filter) if isinstance(related.field, WeakForeignKey): update = {related.field.name: None} q.update(**update) else: q.delete() i += CHUNK super(EnhancedQuerySet, self).delete()
Ancestors (in MRO)
- EnhancedQuerySet
- django.db.models.query.QuerySet
- __builtin__.object
Class variables
var value_annotation
Instance variables
var db
Return the database that will be used if this query is executed now
var ordered
Returns True if the QuerySet is ordered -- i.e. has an order_by() clause or a default ordering on the model.
Methods
def __init__(
self, model=None, query=None, using=None)
def __init__(self, model=None, query=None, using=None): self.model = model self._db = using 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}}
def aggregate(
self, *args, **kwargs)
Returns 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.
def aggregate(self, *args, **kwargs): """ Returns 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.") for arg in args: kwargs[arg.default_alias] = arg query = self.query.clone() for (alias, aggregate_expr) in kwargs.items(): query.add_aggregate(aggregate_expr, self.model, alias, is_summary=True) return query.get_aggregation(using=self.db)
def all(
self)
Returns a new QuerySet that is a copy of the current one. This allows a QuerySet to proxy for a model manager in some cases.
def all(self): """ Returns 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._clone()
def annotate(
self, *args, **kwargs)
Return a query set in which the returned objects have been annotated with data aggregated from related fields.
def annotate(self, *args, **kwargs): """ Return a query set in which the returned objects have been annotated with data aggregated from related fields. """ for arg in args: if arg.default_alias in kwargs: raise ValueError("The named annotation '%s' conflicts with the " "default name for another annotation." % arg.default_alias) kwargs[arg.default_alias] = arg names = getattr(self, '_fields', None) if names is None: names = set(self.model._meta.get_all_field_names()) for aggregate in kwargs: if aggregate in names: raise ValueError("The annotation '%s' conflicts with a field on " "the model." % aggregate) obj = self._clone() obj._setup_aggregate_query(list(kwargs)) # Add the aggregates to the query for (alias, aggregate_expr) in kwargs.items(): obj.query.add_aggregate(aggregate_expr, self.model, alias, is_summary=False) return obj
def bulk_create(
self, objs, batch_size=None)
Inserts each of the instances into the database. This does not call save() on each of the instances, does not send any pre/post save signals, and does not set the primary key attribute if it is an autoincrement field.
def bulk_create(self, objs, batch_size=None): """ Inserts each of the instances into the database. This does *not* call save() on each of the instances, does not send any pre/post save signals, and does not set the primary key attribute if it is an autoincrement field. """ # So this case is fun. When you bulk insert you don't get the primary # keys back (if it's an autoincrement), 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, # and 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. Some databases might allow doing # this by using RETURNING clause for the insert query. We're punting # on these for now because they are relatively rare cases. assert batch_size is None or batch_size > 0 if self.model._meta.parents: raise ValueError("Can't bulk create an inherited model") if not objs: return objs self._for_write = True connection = connections[self.db] fields = self.model._meta.local_concrete_fields with transaction.commit_on_success_unless_managed(using=self.db): if (connection.features.can_combine_inserts_with_and_without_auto_increment_pk and self.model._meta.has_auto_field): self._batched_insert(objs, fields, batch_size) else: objs_with_pk, objs_without_pk = partition(lambda o: o.pk is None, objs) if objs_with_pk: self._batched_insert(objs_with_pk, fields, batch_size) if objs_without_pk: fields= [f for f in fields if not isinstance(f, AutoField)] self._batched_insert(objs_without_pk, fields, batch_size) return objs
def complex_filter(
self, filter_obj)
Returns a new QuerySet instance with filter_obj added to the filters.
filter_obj can be a Q object (or anything with an add_to_query() method) 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.
def complex_filter(self, filter_obj): """ Returns a new QuerySet instance with filter_obj added to the filters. filter_obj can be a Q object (or anything with an add_to_query() method) 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) or hasattr(filter_obj, 'add_to_query'): clone = self._clone() clone.query.add_q(filter_obj) return clone else: return self._filter_or_exclude(None, **filter_obj)
def count(
self)
Performs a SELECT COUNT() and returns the number of records as an integer.
If the QuerySet is already fully cached this simply returns the length of the cached results set to avoid multiple SELECT COUNT(*) calls.
def count(self): """ Performs a SELECT COUNT() and returns the number of records as an integer. If the QuerySet is already fully cached this simply returns 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)
def create(
self, **kwargs)
Creates a new object with the given kwargs, saving it to the database and returning the created object.
def create(self, **kwargs): """ Creates a new object with the given kwargs, saving it to the database and returning the created object. """ obj = self.model(**kwargs) self._for_write = True obj.save(force_insert=True, using=self.db) return obj
def dates(
self, field_name, kind, order='ASC')
Returns a list of date objects representing all available dates for the given field_name, scoped to 'kind'.
def dates(self, field_name, kind, order='ASC'): """ Returns a list of date objects representing all available dates for the given field_name, scoped to 'kind'. """ assert kind in ("year", "month", "day"), \ "'kind' must be one of 'year', 'month' or 'day'." assert order in ('ASC', 'DESC'), \ "'order' must be either 'ASC' or 'DESC'." return self._clone(klass=DateQuerySet, setup=True, _field_name=field_name, _kind=kind, _order=order)
def datetimes(
self, field_name, kind, order='ASC', tzinfo=None)
Returns a list of datetime objects representing all available datetimes for the given field_name, scoped to 'kind'.
def datetimes(self, field_name, kind, order='ASC', tzinfo=None): """ Returns a list of datetime objects representing all available datetimes for the given field_name, scoped to 'kind'. """ assert kind in ("year", "month", "day", "hour", "minute", "second"), \ "'kind' must be one of 'year', 'month', 'day', 'hour', 'minute' or 'second'." assert order in ('ASC', 'DESC'), \ "'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._clone(klass=DateTimeQuerySet, setup=True, _field_name=field_name, _kind=kind, _order=order, _tzinfo=tzinfo)
def defer(
self, *fields)
Defers the loading of data for certain fields until they are accessed. The set of fields to defer is added 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 all deferrals are removed (None acts as a reset option).
def defer(self, *fields): """ Defers the loading of data for certain fields until they are accessed. The set of fields to defer is added 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 all deferrals are removed (None acts as a reset option). """ clone = self._clone() if fields == (None,): clone.query.clear_deferred_loading() else: clone.query.add_deferred_loading(fields) return clone
def delete(
self)
def delete(self): CHUNK=1024 objects = self.model._meta.get_all_related_objects() ii = self.count() values = self.values_list('pk') for related in objects: i = 0 while i < ii: ids = [v[0] for v in values[i:i + CHUNK]] filter = {related.field.name + '__pk__in': ids} q = related.model.objects.filter(**filter) if isinstance(related.field, WeakForeignKey): update = {related.field.name: None} q.update(**update) else: q.delete() i += CHUNK super(EnhancedQuerySet, self).delete()
def distinct(
self, *field_names)
Returns a new QuerySet instance that will select only distinct results.
def distinct(self, *field_names): """ Returns a new QuerySet instance that will select only distinct results. """ assert self.query.can_filter(), \ "Cannot create distinct fields once a slice has been taken." obj = self._clone() obj.query.add_distinct_fields(*field_names) return obj
def earliest(
self, field_name=None)
def earliest(self, field_name=None): return self._earliest_or_latest(field_name=field_name, direction="")
def exclude(
self, *args, **kwargs)
Returns a new QuerySet instance with NOT (args) ANDed to the existing set.
def exclude(self, *args, **kwargs): """ Returns a new QuerySet instance with NOT (args) ANDed to the existing set. """ return self._filter_or_exclude(True, *args, **kwargs)
def exists(
self)
def exists(self): if self._result_cache is None: return self.query.has_results(using=self.db) return bool(self._result_cache)
def extra(
self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None)
Adds extra SQL fragments to the query.
def extra(self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None): """ Adds extra SQL fragments to the query. """ assert self.query.can_filter(), \ "Cannot change a query once a slice has been taken" clone = self._clone() clone.query.add_extra(select, select_params, where, params, tables, order_by) return clone
def filter(
self, *args, **kwargs)
Returns a new QuerySet instance with the args ANDed to the existing set.
def filter(self, *args, **kwargs): """ Returns a new QuerySet instance with the args ANDed to the existing set. """ return self._filter_or_exclude(False, *args, **kwargs)
def first(
self)
Returns the first object of a query, returns None if no match is found.
def first(self): """ Returns the first object of a query, returns None if no match is found. """ qs = self if self.ordered else self.order_by('pk') try: return qs[0] except IndexError: return None
def get(
self, *args, **kwargs)
Performs the query and returns a single object matching the given keyword arguments.
def get(self, *args, **kwargs): """ Performs the query and returns a single object matching the given keyword arguments. """ clone = self.filter(*args, **kwargs) if self.query.can_filter(): clone = clone.order_by() 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))
def get_or_create(
self, **kwargs)
Looks up an object with the given kwargs, creating one if necessary. Returns a tuple of (object, created), where created is a boolean specifying whether an object was created.
def get_or_create(self, **kwargs): """ Looks up an object with the given kwargs, creating one if necessary. Returns a tuple of (object, created), where created is a boolean specifying whether an object was created. """ defaults = kwargs.pop('defaults', {}) lookup = kwargs.copy() for f in self.model._meta.fields: if f.attname in lookup: lookup[f.name] = lookup.pop(f.attname) try: self._for_write = True return self.get(**lookup), False except self.model.DoesNotExist: try: params = dict((k, v) for k, v in kwargs.items() if LOOKUP_SEP not in k) params.update(defaults) obj = self.model(**params) with transaction.atomic(using=self.db): obj.save(force_insert=True, using=self.db) return obj, True except DatabaseError: exc_info = sys.exc_info() try: return self.get(**lookup), False except self.model.DoesNotExist: # Re-raise the DatabaseError with its original traceback. six.reraise(*exc_info)
def in_bulk(
self, id_list)
Returns a dictionary mapping each of the given IDs to the object with that ID.
def in_bulk(self, id_list): """ Returns a dictionary mapping each of the given IDs to the object with that ID. """ assert self.query.can_filter(), \ "Cannot use 'limit' or 'offset' with in_bulk" if not id_list: return {} qs = self.filter(pk__in=id_list).order_by() return dict([(obj._get_pk_val(), obj) for obj in qs])
def iterator(
self)
An iterator over the results from applying this QuerySet to the database.
def iterator(self): """ An iterator over the results from applying this QuerySet to the database. """ fill_cache = False if connections[self.db].features.supports_select_related: fill_cache = self.query.select_related if isinstance(fill_cache, dict): requested = fill_cache else: requested = None max_depth = self.query.max_depth extra_select = list(self.query.extra_select) aggregate_select = list(self.query.aggregate_select) only_load = self.query.get_loaded_field_names() if not fill_cache: fields = self.model._meta.concrete_fields load_fields = [] # If only/defer clauses have been specified, # build the list of fields that are to be loaded. if only_load: for field, model in self.model._meta.get_concrete_fields_with_model(): if model is None: model = self.model try: if field.name in only_load[model]: # Add a field that has been explicitly included load_fields.append(field.name) except KeyError: # Model wasn't explicitly listed in the only_load table # Therefore, we need to load all fields from this model load_fields.append(field.name) index_start = len(extra_select) aggregate_start = index_start + len(load_fields or self.model._meta.concrete_fields) skip = None if load_fields and not fill_cache: # Some fields have been deferred, so we have to initialise # via keyword arguments. skip = set() init_list = [] for field in fields: if field.name not in load_fields: skip.add(field.attname) else: init_list.append(field.attname) model_cls = deferred_class_factory(self.model, skip) # Cache db and model outside the loop db = self.db model = self.model compiler = self.query.get_compiler(using=db) if fill_cache: klass_info = get_klass_info(model, max_depth=max_depth, requested=requested, only_load=only_load) for row in compiler.results_iter(): if fill_cache: obj, _ = get_cached_row(row, index_start, db, klass_info, offset=len(aggregate_select)) else: # Omit aggregates in object creation. row_data = row[index_start:aggregate_start] if skip: obj = model_cls(**dict(zip(init_list, row_data))) else: obj = model(*row_data) # Store the source database of the object obj._state.db = db # This object came from the database; it's not being added. obj._state.adding = False if extra_select: for i, k in enumerate(extra_select): setattr(obj, k, row[i]) # Add the aggregates to the model if aggregate_select: for i, aggregate in enumerate(aggregate_select): setattr(obj, aggregate, row[i + aggregate_start]) # Add the known related objects to the model, if there are any if self._known_related_objects: for field, rel_objs in self._known_related_objects.items(): # Avoid overwriting objects loaded e.g. by select_related if hasattr(obj, field.get_cache_name()): continue pk = getattr(obj, field.get_attname()) try: rel_obj = rel_objs[pk] except KeyError: pass # may happen in qs1 | qs2 scenarios else: setattr(obj, field.name, rel_obj) yield obj
def last(
self)
Returns the last object of a query, returns None if no match is found.
def last(self): """ Returns the last object of a query, returns None if no match is found. """ qs = self.reverse() if self.ordered else self.order_by('-pk') try: return qs[0] except IndexError: return None
def latest(
self, field_name=None)
def latest(self, field_name=None): return self._earliest_or_latest(field_name=field_name, direction="-")
def none(
self)
Returns an empty QuerySet.
def none(self): """ Returns an empty QuerySet. """ clone = self._clone() clone.query.set_empty() 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.
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. """ 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().") clone = self._clone() clone.query.add_immediate_loading(fields) return clone
def order_by(
self, *field_names)
Returns a new QuerySet instance with the ordering changed.
def order_by(self, *field_names): """ Returns a new QuerySet instance with the ordering changed. """ assert self.query.can_filter(), \ "Cannot reorder a query once a slice has been taken." obj = self._clone() obj.query.clear_ordering(force_empty=False) obj.query.add_ordering(*field_names) return obj
Returns 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, the list of lookups to prefetch is appended to. If prefetch_related(None) is called, the the list is cleared.
def reverse(
self)
Reverses the ordering of the QuerySet.
def reverse(self): """ Reverses the ordering of the QuerySet. """ clone = self._clone() clone.query.standard_ordering = not clone.query.standard_ordering return clone
def select_for_update(
self, **kwargs)
Returns a new QuerySet instance that will select objects with a FOR UPDATE lock.
def select_for_update(self, **kwargs): """ Returns a new QuerySet instance that will select objects with a FOR UPDATE lock. """ # Default to false for nowait nowait = kwargs.pop('nowait', False) obj = self._clone() obj._for_write = True obj.query.select_for_update = True obj.query.select_for_update_nowait = nowait return obj
Returns 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, the list is cleared.
def update(
self, **kwargs)
Updates all elements in the current QuerySet, setting all the given fields to the appropriate values.
def update(self, **kwargs): """ Updates all elements in the current QuerySet, setting all the given fields to the appropriate values. """ assert self.query.can_filter(), \ "Cannot update a query once a slice has been taken." self._for_write = True query = self.query.clone(sql.UpdateQuery) query.add_update_values(kwargs) with transaction.commit_on_success_unless_managed(using=self.db): rows = query.get_compiler(self.db).execute_sql(None) self._result_cache = None return rows
def using(
self, alias)
Selects which database this QuerySet should excecute its query against.
def using(self, alias): """ Selects which database this QuerySet should excecute its query against. """ clone = self._clone() clone._db = alias return clone
def values(
self, *fields)
def values(self, *fields): return self._clone(klass=ValuesQuerySet, setup=True, _fields=fields)
def values_list(
self, *fields, **kwargs)
def values_list(self, *fields, **kwargs): flat = kwargs.pop('flat', False) if kwargs: raise TypeError('Unexpected keyword arguments to values_list: %s' % (list(kwargs),)) if flat and len(fields) > 1: raise TypeError("'flat' is not valid when values_list is called with more than one field.") return self._clone(klass=ValuesListQuerySet, setup=True, flat=flat, _fields=fields)
class MetaCore
class MetaCore: app_label = 'telemeta'
class ModelCore
class ModelCore(EnhancedModel, DirtyFieldsMixin): @classmethod def required_fields(cls): required = [] for field in cls._meta.fields: if not field.blank: required.append(field) return required def save(self, force_insert=False, force_update=False, *args, **kwargs): required = self.required_fields() for field in required: if not getattr(self, field.name): raise RequiredFieldError(self, field) super(ModelCore, self).save(force_insert, force_update, *args, **kwargs) @classmethod def get_dom_name(cls): "Convert the class name to a DOM element name" clsname = cls.__name__ return clsname[0].lower() + clsname[1:] @staticmethod def get_dom_field_name(field_name): "Convert the class name to a DOM element name" tokens = field_name.split('_') name = tokens[0] for t in tokens[1:]: name += t[0].upper() + t[1:] return name def to_dom(self): "Return the DOM representation of this media object" impl = getDOMImplementation() root = self.get_dom_name() doc = impl.createDocument(None, root, None) top = doc.documentElement top.setAttribute("id", str(self.pk)) fields = self.to_dict() for name, value in fields.iteritems(): element = doc.createElement(self.get_dom_field_name(name)) if isinstance(value, EnhancedModel): element.setAttribute('key', str(value.pk)) value = unicode(value) element.appendChild(doc.createTextNode(value)) top.appendChild(element) return doc def to_dict(self): "Return model fields as a dict of name/value pairs" fields_dict = {} for field in self._meta.fields: fields_dict[field.name] = getattr(self, field.name) return fields_dict def to_list(self): "Return model fields as a list" fields_list = [] for field in self._meta.fields: fields_list.append({'name': field.name, 'value': unicode(getattr(self, field.name))}) return fields_list @classmethod def field_label(cls, field_name=None): if field_name: try: return cls._meta.get_field(field_name).verbose_name except FieldDoesNotExist: try: return getattr(cls, field_name).verbose_name except AttributeError: return field_name else: return cls._meta.verbose_name class Meta: abstract = True
Ancestors (in MRO)
- ModelCore
- EnhancedModel
- django.db.models.base.Model
- dirtyfields.dirtyfields.DirtyFieldsMixin
- __builtin__.object
Class variables
var ENABLE_M2M_CHECK
var compare_function
Static methods
def get_dom_field_name(
field_name)
Convert the class name to a DOM element name
@staticmethod def get_dom_field_name(field_name): "Convert the class name to a DOM element name" tokens = field_name.split('_') name = tokens[0] for t in tokens[1:]: name += t[0].upper() + t[1:] return name
Instance variables
Methods
def __init__(
self, *args, **kwargs)
Inheritance:
EnhancedModel
.__init__
def __init__(self, *args, **kwargs): signals.pre_init.send(sender=self.__class__, args=args, kwargs=kwargs) # Set up the storage for instance state self._state = ModelState() # There is a rather weird disparity here; if kwargs, it's set, then args # overrides it. It should be one or the other; don't duplicate the work # The reason for the kwargs check is that standard iterator passes in by # args, and instantiation for iteration is 33% faster. args_len = len(args) if args_len > len(self._meta.concrete_fields): # Daft, but matches old exception sans the err msg. raise IndexError("Number of args exceeds number of fields") if not kwargs: fields_iter = iter(self._meta.concrete_fields) # The ordering of the zip calls matter - zip throws StopIteration # when an iter throws it. So if the first iter throws it, the second # is *not* consumed. We rely on this, so don't change the order # without changing the logic. for val, field in zip(args, fields_iter): setattr(self, field.attname, val) else: # Slower, kwargs-ready version. fields_iter = iter(self._meta.fields) for val, field in zip(args, fields_iter): setattr(self, field.attname, val) kwargs.pop(field.name, None) # Maintain compatibility with existing calls. if isinstance(field.rel, ManyToOneRel): kwargs.pop(field.attname, None) # Now we're left with the unprocessed fields that *must* come from # keywords, or default. for field in fields_iter: is_related_object = False # This slightly odd construct is so that we can access any # data-descriptor object (DeferredAttribute) without triggering its # __get__ method. if (field.attname not in kwargs and (isinstance(self.__class__.__dict__.get(field.attname), DeferredAttribute) or field.column is None)): # This field will be populated on request. continue if kwargs: if isinstance(field.rel, ForeignObjectRel): try: # Assume object instance was passed in. rel_obj = kwargs.pop(field.name) is_related_object = True except KeyError: try: # Object instance wasn't passed in -- must be an ID. val = kwargs.pop(field.attname) except KeyError: val = field.get_default() else: # Object instance was passed in. Special case: You can # pass in "None" for related objects if it's allowed. if rel_obj is None and field.null: val = None else: try: val = kwargs.pop(field.attname) except KeyError: # This is done with an exception rather than the # default argument on pop because we don't want # get_default() to be evaluated, and then not used. # Refs #12057. val = field.get_default() else: val = field.get_default() if is_related_object: # If we are passed a related instance, set it using the # field.name instead of field.attname (e.g. "user" instead of # "user_id") so that the object gets properly cached (and type # checked) by the RelatedObjectDescriptor. setattr(self, field.name, rel_obj) else: setattr(self, field.attname, val) if kwargs: for prop in list(kwargs): try: if isinstance(getattr(self.__class__, prop), property): setattr(self, prop, kwargs.pop(prop)) except AttributeError: pass if kwargs: raise TypeError("'%s' is an invalid keyword argument for this function" % list(kwargs)[0]) super(Model, self).__init__() signals.post_init.send(sender=self.__class__, instance=self)
def clean(
self)
Inheritance:
EnhancedModel
.clean
Hook for doing any extra model-wide validation after clean() has been called on every field by self.clean_fields. Any ValidationError raised by this method will not be associated with a particular field; it will have a special-case association with the field defined by NON_FIELD_ERRORS.
def clean(self): """ Hook for doing any extra model-wide validation after clean() has been called on every field by self.clean_fields. Any ValidationError raised by this method will not be associated with a particular field; it will have a special-case association with the field defined by NON_FIELD_ERRORS. """ pass
def clean_fields(
self, exclude=None)
Inheritance:
EnhancedModel
.clean_fields
Cleans all fields and raises a ValidationError containing message_dict of all validation errors if any occur.
def clean_fields(self, exclude=None): """ Cleans all fields and raises a ValidationError containing message_dict of all validation errors if any occur. """ if exclude is None: exclude = [] errors = {} for f in self._meta.fields: if f.name in exclude: continue # Skip validation for empty fields with blank=True. The developer # is responsible for making sure they have a valid value. raw_value = getattr(self, f.attname) if f.blank and raw_value in f.empty_values: continue try: setattr(self, f.attname, f.clean(raw_value, self)) except ValidationError as e: errors[f.name] = e.error_list if errors: raise ValidationError(errors)
def date_error_message(
self, lookup_type, field, unique_for)
Inheritance:
EnhancedModel
.date_error_message
def date_error_message(self, lookup_type, field, unique_for): opts = self._meta return _("%(field_name)s must be unique for %(date_field)s %(lookup)s.") % { 'field_name': six.text_type(capfirst(opts.get_field(field).verbose_name)), 'date_field': six.text_type(capfirst(opts.get_field(unique_for).verbose_name)), 'lookup': lookup_type, }
def delete(
self)
Inheritance:
EnhancedModel
.delete
def delete(self): if not self.pk: raise Exception("Can't delete without a primary key") self.__class__.objects.filter(pk=self.pk).delete()
def field_label(
cls, field_name=None)
@classmethod def field_label(cls, field_name=None): if field_name: try: return cls._meta.get_field(field_name).verbose_name except FieldDoesNotExist: try: return getattr(cls, field_name).verbose_name except AttributeError: return field_name else: return cls._meta.verbose_name
def full_clean(
self, exclude=None, validate_unique=True)
Inheritance:
EnhancedModel
.full_clean
Calls clean_fields, clean, and validate_unique, on the model,
and raises a ValidationError
for any errors that occurred.
def full_clean(self, exclude=None, validate_unique=True): """ Calls clean_fields, clean, and validate_unique, on the model, and raises a ``ValidationError`` for any errors that occurred. """ errors = {} if exclude is None: exclude = [] try: self.clean_fields(exclude=exclude) except ValidationError as e: errors = e.update_error_dict(errors) # Form.clean() is run even if other validation fails, so do the # same with Model.clean() for consistency. try: self.clean() except ValidationError as e: errors = e.update_error_dict(errors) # Run unique checks, but only for fields that passed validation. if validate_unique: for name in errors.keys(): if name != NON_FIELD_ERRORS and name not in exclude: exclude.append(name) try: self.validate_unique(exclude=exclude) except ValidationError as e: errors = e.update_error_dict(errors) if errors: raise ValidationError(errors)
def get_dirty_fields(
self, check_relationship=False, check_m2m=None, verbose=False)
def get_dirty_fields(self, check_relationship=False, check_m2m=None, verbose=False): if self._state.adding: # If the object has not yet been saved in the database, all fields are considered dirty # for consistency (see https://github.com/romgar/django-dirtyfields/issues/65 for more details) pk_specified = self.pk is not None initial_dict = self._as_dict(check_relationship, include_primary_key=pk_specified) return initial_dict if check_m2m is not None and not self.ENABLE_M2M_CHECK: raise ValueError("You can't check m2m fields if ENABLE_M2M_CHECK is set to False") modified_fields = compare_states(self._as_dict(check_relationship), self._original_state, self.compare_function) if check_m2m: modified_m2m_fields = compare_states(check_m2m, self._original_m2m_state, self.compare_function) modified_fields.update(modified_m2m_fields) if not verbose: # Keeps backward compatibility with previous function return modified_fields = {key: value['saved'] for key, value in modified_fields.items()} return modified_fields
def get_dom_name(
cls)
Convert the class name to a DOM element name
@classmethod def get_dom_name(cls): "Convert the class name to a DOM element name" clsname = cls.__name__ return clsname[0].lower() + clsname[1:]
def is_dirty(
self, check_relationship=False, check_m2m=None)
def is_dirty(self, check_relationship=False, check_m2m=None): return {} != self.get_dirty_fields(check_relationship=check_relationship, check_m2m=check_m2m)
def prepare_database_save(
self, unused)
Inheritance:
EnhancedModel
.prepare_database_save
def prepare_database_save(self, unused): if self.pk is None: raise ValueError("Unsaved model instance %r cannot be used in an ORM query." % self) return self.pk
def required_fields(
cls)
@classmethod def required_fields(cls): required = [] for field in cls._meta.fields: if not field.blank: required.append(field) return required
def save(
self, force_insert=False, force_update=False, *args, **kwargs)
Inheritance:
EnhancedModel
.save
Saves the current instance. Override this in a subclass if you want to control the saving process.
The 'force_insert' and 'force_update' parameters can be used to insist that the "save" must be an SQL insert or update (or equivalent for non-SQL backends), respectively. Normally, they should not be set.
def save(self, force_insert=False, force_update=False, *args, **kwargs): required = self.required_fields() for field in required: if not getattr(self, field.name): raise RequiredFieldError(self, field) super(ModelCore, self).save(force_insert, force_update, *args, **kwargs)
def save_base(
self, raw=False, force_insert=False, force_update=False, using=None, update_fields=None)
Inheritance:
EnhancedModel
.save_base
Handles the parts of saving which should be done only once per save, yet need to be done in raw saves, too. This includes some sanity checks and signal sending.
The 'raw' argument is telling save_base not to save any parent models and not to do any changes to the values before save. This is used by fixture loading.
def save_base(self, raw=False, force_insert=False, force_update=False, using=None, update_fields=None): """ Handles the parts of saving which should be done only once per save, yet need to be done in raw saves, too. This includes some sanity checks and signal sending. The 'raw' argument is telling save_base not to save any parent models and not to do any changes to the values before save. This is used by fixture loading. """ using = using or router.db_for_write(self.__class__, instance=self) assert not (force_insert and (force_update or update_fields)) assert update_fields is None or len(update_fields) > 0 cls = origin = self.__class__ # Skip proxies, but keep the origin as the proxy model. if cls._meta.proxy: cls = cls._meta.concrete_model meta = cls._meta if not meta.auto_created: signals.pre_save.send(sender=origin, instance=self, raw=raw, using=using, update_fields=update_fields) with transaction.commit_on_success_unless_managed(using=using, savepoint=False): if not raw: self._save_parents(cls, using, update_fields) updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields) # Store the database on which the object was saved self._state.db = using # Once saved, this is no longer a to-be-added instance. self._state.adding = False # Signal that the save is complete if not meta.auto_created: signals.post_save.send(sender=origin, instance=self, created=(not updated), update_fields=update_fields, raw=raw, using=using)
def save_dirty_fields(
self)
def save_dirty_fields(self): dirty_fields = self.get_dirty_fields(check_relationship=True) save_specific_fields(self, dirty_fields)
def serializable_value(
self, field_name)
Inheritance:
EnhancedModel
.serializable_value
Returns the value of the field name for this instance. If the field is a foreign key, returns the id value, instead of the object. If there's no Field object with this name on the model, the model attribute's value is returned directly.
Used to serialize a field's value (in the serializer, or form output, for example). Normally, you would just access the attribute directly and not use this method.
def serializable_value(self, field_name): """ Returns the value of the field name for this instance. If the field is a foreign key, returns the id value, instead of the object. If there's no Field object with this name on the model, the model attribute's value is returned directly. Used to serialize a field's value (in the serializer, or form output, for example). Normally, you would just access the attribute directly and not use this method. """ try: field = self._meta.get_field_by_name(field_name)[0] except FieldDoesNotExist: return getattr(self, field_name) return getattr(self, field.attname)
def to_dict(
self)
Return model fields as a dict of name/value pairs
def to_dict(self): "Return model fields as a dict of name/value pairs" fields_dict = {} for field in self._meta.fields: fields_dict[field.name] = getattr(self, field.name) return fields_dict
def to_dom(
self)
Return the DOM representation of this media object
def to_dom(self): "Return the DOM representation of this media object" impl = getDOMImplementation() root = self.get_dom_name() doc = impl.createDocument(None, root, None) top = doc.documentElement top.setAttribute("id", str(self.pk)) fields = self.to_dict() for name, value in fields.iteritems(): element = doc.createElement(self.get_dom_field_name(name)) if isinstance(value, EnhancedModel): element.setAttribute('key', str(value.pk)) value = unicode(value) element.appendChild(doc.createTextNode(value)) top.appendChild(element) return doc
def to_list(
self)
Return model fields as a list
def to_list(self): "Return model fields as a list" fields_list = [] for field in self._meta.fields: fields_list.append({'name': field.name, 'value': unicode(getattr(self, field.name))}) return fields_list
def unique_error_message(
self, model_class, unique_check)
Inheritance:
EnhancedModel
.unique_error_message
def unique_error_message(self, model_class, unique_check): opts = model_class._meta model_name = capfirst(opts.verbose_name) # A unique field if len(unique_check) == 1: field_name = unique_check[0] field = opts.get_field(field_name) field_label = capfirst(field.verbose_name) # Insert the error into the error dict, very sneaky return field.error_messages['unique'] % { 'model_name': six.text_type(model_name), 'field_label': six.text_type(field_label) } # unique_together else: field_labels = [capfirst(opts.get_field(f).verbose_name) for f in unique_check] field_labels = get_text_list(field_labels, _('and')) return _("%(model_name)s with this %(field_label)s already exists.") % { 'model_name': six.text_type(model_name), 'field_label': six.text_type(field_labels) }
def validate_unique(
self, exclude=None)
Inheritance:
EnhancedModel
.validate_unique
Checks unique constraints on the model and raises ValidationError
if any failed.
def validate_unique(self, exclude=None): """ Checks unique constraints on the model and raises ``ValidationError`` if any failed. """ unique_checks, date_checks = self._get_unique_checks(exclude=exclude) errors = self._perform_unique_checks(unique_checks) date_errors = self._perform_date_checks(date_checks) for k, v in date_errors.items(): errors.setdefault(k, []).extend(v) if errors: raise ValidationError(errors)