from __future__ import unicode_literals import copy import sys from functools import update_wrapper from django.utils.six.moves import zip import django.db.models.manager # Imported to register signal handler. from django.conf import settings from django.core.exceptions import (ObjectDoesNotExist, MultipleObjectsReturned, FieldError, ValidationError, NON_FIELD_ERRORS) from django.db.models.fields import AutoField, FieldDoesNotExist from django.db.models.fields.related import (ForeignObjectRel, ManyToOneRel, OneToOneField, add_lazy_relation) from django.db import (router, transaction, DatabaseError, DEFAULT_DB_ALIAS) from django.db.models.query import Q from django.db.models.query_utils import DeferredAttribute, deferred_class_factory from django.db.models.deletion import Collector from django.db.models.options import Options from django.db.models import signals from django.db.models.loading import register_models, get_model, MODELS_MODULE_NAME from django.utils.translation import ugettext_lazy as _ from django.utils.functional import curry from django.utils.encoding import force_str, force_text from django.utils import six from django.utils.text import get_text_list, capfirst def subclass_exception(name, parents, module, attached_to=None): """ Create exception subclass. Used by ModelBase below. If 'attached_to' is supplied, the exception will be created in a way that allows it to be pickled, assuming the returned exception class will be added as an attribute to the 'attached_to' class. """ class_dict = {'__module__': module} if attached_to is not None: def __reduce__(self): # Exceptions are special - they've got state that isn't # in self.__dict__. We assume it is all in self.args. return (unpickle_inner_exception, (attached_to, name), self.args) def __setstate__(self, args): self.args = args class_dict['__reduce__'] = __reduce__ class_dict['__setstate__'] = __setstate__ return type(name, parents, class_dict) class ModelBase(type): """ Metaclass for all models. """ def __new__(cls, name, bases, attrs): super_new = super(ModelBase, cls).__new__ # six.with_metaclass() inserts an extra class called 'NewBase' in the # inheritance tree: Model -> NewBase -> object. But the initialization # should be executed only once for a given model class. # attrs will never be empty for classes declared in the standard way # (ie. with the `class` keyword). This is quite robust. if name == 'NewBase' and attrs == {}: return super_new(cls, name, bases, attrs) # Also ensure initialization is only performed for subclasses of Model # (excluding Model class itself). parents = [b for b in bases if isinstance(b, ModelBase) and not (b.__name__ == 'NewBase' and b.__mro__ == (b, object))] if not parents: return super_new(cls, name, bases, attrs) # Create the class. module = attrs.pop('__module__') new_class = super_new(cls, name, bases, {'__module__': module}) attr_meta = attrs.pop('Meta', None) abstract = getattr(attr_meta, 'abstract', False) if not attr_meta: meta = getattr(new_class, 'Meta', None) else: meta = attr_meta base_meta = getattr(new_class, '_meta', None) if getattr(meta, 'app_label', None) is None: # Figure out the app_label by looking one level up from the package # or module named 'models'. If no such package or module exists, # fall back to looking one level up from the module this model is # defined in. # For 'django.contrib.sites.models', this would be 'sites'. # For 'geo.models.places' this would be 'geo'. model_module = sys.modules[new_class.__module__] package_components = model_module.__name__.split('.') package_components.reverse() # find the last occurrence of 'models' try: app_label_index = package_components.index(MODELS_MODULE_NAME) + 1 except ValueError: app_label_index = 1 kwargs = {"app_label": package_components[app_label_index]} else: kwargs = {} new_class.add_to_class('_meta', Options(meta, **kwargs)) if not abstract: new_class.add_to_class('DoesNotExist', subclass_exception(str('DoesNotExist'), tuple(x.DoesNotExist for x in parents if hasattr(x, '_meta') and not x._meta.abstract) or (ObjectDoesNotExist,), module, attached_to=new_class)) new_class.add_to_class('MultipleObjectsReturned', subclass_exception(str('MultipleObjectsReturned'), tuple(x.MultipleObjectsReturned for x in parents if hasattr(x, '_meta') and not x._meta.abstract) or (MultipleObjectsReturned,), module, attached_to=new_class)) if base_meta and not base_meta.abstract: # Non-abstract child classes inherit some attributes from their # non-abstract parent (unless an ABC comes before it in the # method resolution order). if not hasattr(meta, 'ordering'): new_class._meta.ordering = base_meta.ordering if not hasattr(meta, 'get_latest_by'): new_class._meta.get_latest_by = base_meta.get_latest_by is_proxy = new_class._meta.proxy # If the model is a proxy, ensure that the base class # hasn't been swapped out. if is_proxy and base_meta and base_meta.swapped: raise TypeError("%s cannot proxy the swapped model '%s'." % (name, base_meta.swapped)) if getattr(new_class, '_default_manager', None): if not is_proxy: # Multi-table inheritance doesn't inherit default manager from # parents. new_class._default_manager = None new_class._base_manager = None else: # Proxy classes do inherit parent's default manager, if none is # set explicitly. new_class._default_manager = new_class._default_manager._copy_to_model(new_class) new_class._base_manager = new_class._base_manager._copy_to_model(new_class) # Bail out early if we have already created this class. m = new_class._meta.app_cache.get_model(new_class._meta.app_label, name, seed_cache=False, only_installed=False) if m is not None: return m # Add all attributes to the class. for obj_name, obj in attrs.items(): new_class.add_to_class(obj_name, obj) # All the fields of any type declared on this model new_fields = new_class._meta.local_fields + \ new_class._meta.local_many_to_many + \ new_class._meta.virtual_fields field_names = set(f.name for f in new_fields) # Basic setup for proxy models. if is_proxy: base = None for parent in [kls for kls in parents if hasattr(kls, '_meta')]: if parent._meta.abstract: if parent._meta.fields: raise TypeError("Abstract base class containing model fields not permitted for proxy model '%s'." % name) else: continue if base is not None: raise TypeError("Proxy model '%s' has more than one non-abstract model base class." % name) else: base = parent if base is None: raise TypeError("Proxy model '%s' has no non-abstract model base class." % name) if (new_class._meta.local_fields or new_class._meta.local_many_to_many): raise FieldError("Proxy model '%s' contains model fields." % name) new_class._meta.setup_proxy(base) new_class._meta.concrete_model = base._meta.concrete_model else: new_class._meta.concrete_model = new_class # Collect the parent links for multi-table inheritance. parent_links = {} for base in reversed([new_class] + parents): # Conceptually equivalent to `if base is Model`. if not hasattr(base, '_meta'): continue # Skip concrete parent classes. if base != new_class and not base._meta.abstract: continue # Locate OneToOneField instances. for field in base._meta.local_fields: if isinstance(field, OneToOneField): parent_links[field.rel.to] = field # Do the appropriate setup for any model parents. for base in parents: original_base = base if not hasattr(base, '_meta'): # Things without _meta aren't functional models, so they're # uninteresting parents. continue parent_fields = base._meta.local_fields + base._meta.local_many_to_many # Check for clashes between locally declared fields and those # on the base classes (we cannot handle shadowed fields at the # moment). for field in parent_fields: if field.name in field_names: raise FieldError('Local field %r in class %r clashes ' 'with field of similar name from ' 'base class %r' % (field.name, name, base.__name__)) if not base._meta.abstract: # Concrete classes... base = base._meta.concrete_model if base in parent_links: field = parent_links[base] elif not is_proxy: attr_name = '%s_ptr' % base._meta.model_name field = OneToOneField(base, name=attr_name, auto_created=True, parent_link=True) new_class.add_to_class(attr_name, field) else: field = None new_class._meta.parents[base] = field else: # .. and abstract ones. for field in parent_fields: new_class.add_to_class(field.name, copy.deepcopy(field)) # Pass any non-abstract parent classes onto child. new_class._meta.parents.update(base._meta.parents) # Inherit managers from the abstract base classes. new_class.copy_managers(base._meta.abstract_managers) # Proxy models inherit the non-abstract managers from their base, # unless they have redefined any of them. if is_proxy: new_class.copy_managers(original_base._meta.concrete_managers) # Inherit virtual fields (like GenericForeignKey) from the parent # class for field in base._meta.virtual_fields: if base._meta.abstract and field.name in field_names: raise FieldError('Local field %r in class %r clashes ' 'with field of similar name from ' 'abstract base class %r' % (field.name, name, base.__name__)) new_class.add_to_class(field.name, copy.deepcopy(field)) if abstract: # Abstract base models can't be instantiated and don't appear in # the list of models for an app. We do the final setup for them a # little differently from normal models. attr_meta.abstract = False new_class.Meta = attr_meta return new_class new_class._prepare() new_class._meta.app_cache.register_models(new_class._meta.app_label, new_class) # Because of the way imports happen (recursively), we may or may not be # the first time this model tries to register with the framework. There # should only be one class for each model, so we always return the # registered version. return new_class._meta.app_cache.get_model(new_class._meta.app_label, name, seed_cache=False, only_installed=False) def copy_managers(cls, base_managers): # This is in-place sorting of an Options attribute, but that's fine. base_managers.sort() for _, mgr_name, manager in base_managers: # NOQA (redefinition of _) val = getattr(cls, mgr_name, None) if not val or val is manager: new_manager = manager._copy_to_model(cls) cls.add_to_class(mgr_name, new_manager) def add_to_class(cls, name, value): if hasattr(value, 'contribute_to_class'): value.contribute_to_class(cls, name) else: setattr(cls, name, value) def _prepare(cls): """ Creates some methods once self._meta has been populated. """ opts = cls._meta opts._prepare(cls) if opts.order_with_respect_to: cls.get_next_in_order = curry(cls._get_next_or_previous_in_order, is_next=True) cls.get_previous_in_order = curry(cls._get_next_or_previous_in_order, is_next=False) # defer creating accessors on the foreign class until we are # certain it has been created def make_foreign_order_accessors(field, model, cls): setattr( field.rel.to, 'get_%s_order' % cls.__name__.lower(), curry(method_get_order, cls) ) setattr( field.rel.to, 'set_%s_order' % cls.__name__.lower(), curry(method_set_order, cls) ) add_lazy_relation( cls, opts.order_with_respect_to, opts.order_with_respect_to.rel.to, make_foreign_order_accessors ) # Give the class a docstring -- its definition. if cls.__doc__ is None: cls.__doc__ = "%s(%s)" % (cls.__name__, ", ".join(f.attname for f in opts.fields)) if hasattr(cls, 'get_absolute_url'): cls.get_absolute_url = update_wrapper(curry(get_absolute_url, opts, cls.get_absolute_url), cls.get_absolute_url) signals.class_prepared.send(sender=cls) class ModelState(object): """ A class for storing instance state """ def __init__(self, db=None): self.db = db # If true, uniqueness validation checks will consider this a new, as-yet-unsaved object. # Necessary for correct validation of new instances of objects with explicit (non-auto) PKs. # This impacts validation only; it has no effect on the actual save. self.adding = True class Model(six.with_metaclass(ModelBase)): _deferred = False 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 __repr__(self): try: u = six.text_type(self) except (UnicodeEncodeError, UnicodeDecodeError): u = '[Bad Unicode data]' return force_str('<%s: %s>' % (self.__class__.__name__, u)) def __str__(self): if six.PY2 and hasattr(self, '__unicode__'): return force_text(self).encode('utf-8') return '%s object' % self.__class__.__name__ def __eq__(self, other): if not isinstance(other, Model): return False if self._meta.concrete_model != other._meta.concrete_model: return False my_pk = self._get_pk_val() if my_pk is None: return self is other return my_pk == other._get_pk_val() def __ne__(self, other): return not self.__eq__(other) def __hash__(self): if self._get_pk_val() is None: raise TypeError("Model instances without primary key value are unhashable") return hash(self._get_pk_val()) def __reduce__(self): """ Provides pickling support. Normally, this just dispatches to Python's standard handling. However, for models with deferred field loading, we need to do things manually, as they're dynamically created classes and only module-level classes can be pickled by the default path. """ data = self.__dict__ if not self._deferred: class_id = self._meta.app_label, self._meta.object_name return model_unpickle, (class_id, [], simple_class_factory), data defers = [] for field in self._meta.fields: if isinstance(self.__class__.__dict__.get(field.attname), DeferredAttribute): defers.append(field.attname) model = self._meta.proxy_for_model class_id = model._meta.app_label, model._meta.object_name return (model_unpickle, (class_id, defers, deferred_class_factory), data) def _get_pk_val(self, meta=None): if not meta: meta = self._meta return getattr(self, meta.pk.attname) def _set_pk_val(self, value): return setattr(self, self._meta.pk.attname, value) pk = property(_get_pk_val, _set_pk_val) 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 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) save.alters_data = True 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) save_base.alters_data = True def _save_parents(self, cls, using, update_fields): """ Saves all the parents of cls using values from self. """ meta = cls._meta for parent, field in meta.parents.items(): # Make sure the link fields are synced between parent and self. if (field and getattr(self, parent._meta.pk.attname) is None and getattr(self, field.attname) is not None): setattr(self, parent._meta.pk.attname, getattr(self, field.attname)) self._save_parents(cls=parent, using=using, update_fields=update_fields) self._save_table(cls=parent, using=using, update_fields=update_fields) # Set the parent's PK value to self. if field: setattr(self, field.attname, self._get_pk_val(parent._meta)) # Since we didn't have an instance of the parent handy set # attname directly, bypassing the descriptor. Invalidate # the related object cache, in case it's been accidentally # populated. A fresh instance will be re-built from the # database if necessary. cache_name = field.get_cache_name() if hasattr(self, cache_name): delattr(self, cache_name) def _save_table(self, raw=False, cls=None, force_insert=False, force_update=False, using=None, update_fields=None): """ Does the heavy-lifting involved in saving. Updates or inserts the data for a single table. """ meta = cls._meta non_pks = [f for f in meta.local_concrete_fields if not f.primary_key] if update_fields: non_pks = [f for f in non_pks if f.name in update_fields or f.attname in update_fields] pk_val = self._get_pk_val(meta) pk_set = pk_val is not None if not pk_set and (force_update or update_fields): raise ValueError("Cannot force an update in save() with no primary key.") updated = False # If possible, try an UPDATE. If that doesn't update anything, do an INSERT. if pk_set and not force_insert: base_qs = cls._base_manager.using(using) values = [(f, None, (getattr(self, f.attname) if raw else f.pre_save(self, False))) for f in non_pks] forced_update = update_fields or force_update updated = self._do_update(base_qs, using, pk_val, values, update_fields, forced_update) if force_update and not updated: raise DatabaseError("Forced update did not affect any rows.") if update_fields and not updated: raise DatabaseError("Save with update_fields did not affect any rows.") if not updated: if meta.order_with_respect_to: # If this is a model with an order_with_respect_to # autopopulate the _order field field = meta.order_with_respect_to order_value = cls._base_manager.using(using).filter( **{field.name: getattr(self, field.attname)}).count() self._order = order_value fields = meta.local_concrete_fields if not pk_set: fields = [f for f in fields if not isinstance(f, AutoField)] update_pk = bool(meta.has_auto_field and not pk_set) result = self._do_insert(cls._base_manager, using, fields, update_pk, raw) if update_pk: setattr(self, meta.pk.attname, result) return updated def _do_update(self, base_qs, using, pk_val, values, update_fields, forced_update): """ This method will try to update the model. If the model was updated (in the sense that an update query was done and a matching row was found from the DB) the method will return True. """ filtered = base_qs.filter(pk=pk_val) if not values: # We can end up here when saving a model in inheritance chain where # update_fields doesn't target any field in current model. In that # case we just say the update succeeded. Another case ending up here # is a model with just PK - in that case check that the PK still # exists. return update_fields is not None or filtered.exists() if self._meta.select_on_save and not forced_update: if filtered.exists(): filtered._update(values) return True else: return False return filtered._update(values) > 0 def _do_insert(self, manager, using, fields, update_pk, raw): """ Do an INSERT. If update_pk is defined then this method should return the new pk for the model. """ return manager._insert([self], fields=fields, return_id=update_pk, using=using, raw=raw) def delete(self, using=None): using = using or router.db_for_write(self.__class__, instance=self) assert self._get_pk_val() is not None, "%s object can't be deleted because its %s attribute is set to None." % (self._meta.object_name, self._meta.pk.attname) collector = Collector(using=using) collector.collect([self]) collector.delete() delete.alters_data = True def _get_FIELD_display(self, field): value = getattr(self, field.attname) return force_text(dict(field.flatchoices).get(value, value), strings_only=True) def _get_next_or_previous_by_FIELD(self, field, is_next, **kwargs): if not self.pk: raise ValueError("get_next/get_previous cannot be used on unsaved objects.") op = 'gt' if is_next else 'lt' order = '' if is_next else '-' param = force_text(getattr(self, field.attname)) q = Q(**{'%s__%s' % (field.name, op): param}) q = q | Q(**{field.name: param, 'pk__%s' % op: self.pk}) qs = self.__class__._default_manager.using(self._state.db).filter(**kwargs).filter(q).order_by('%s%s' % (order, field.name), '%spk' % order) try: return qs[0] except IndexError: raise self.DoesNotExist("%s matching query does not exist." % self.__class__._meta.object_name) def _get_next_or_previous_in_order(self, is_next): cachename = "__%s_order_cache" % is_next if not hasattr(self, cachename): op = 'gt' if is_next else 'lt' order = '_order' if is_next else '-_order' order_field = self._meta.order_with_respect_to obj = self._default_manager.filter(**{ order_field.name: getattr(self, order_field.attname) }).filter(**{ '_order__%s' % op: self._default_manager.values('_order').filter(**{ self._meta.pk.name: self.pk }) }).order_by(order)[:1].get() setattr(self, cachename, obj) return getattr(self, cachename) def 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 clean(self): """ Hook for doing any extra model-wide validation after clean() has been called on every field by self.clean_fields. Any ValidationError raised by this method will not be associated with a particular field; it will have a special-case association with the field defined by NON_FIELD_ERRORS. """ pass def validate_unique(self, exclude=None): """ 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) def _get_unique_checks(self, exclude=None): """ Gather a list of checks to perform. Since validate_unique could be called from a ModelForm, some fields may have been excluded; we can't perform a unique check on a model that is missing fields involved in that check. Fields that did not validate should also be excluded, but they need to be passed in via the exclude argument. """ if exclude is None: exclude = [] unique_checks = [] unique_togethers = [(self.__class__, self._meta.unique_together)] for parent_class in self._meta.parents.keys(): if parent_class._meta.unique_together: unique_togethers.append((parent_class, parent_class._meta.unique_together)) for model_class, unique_together in unique_togethers: for check in unique_together: for name in check: # If this is an excluded field, don't add this check. if name in exclude: break else: unique_checks.append((model_class, tuple(check))) # These are checks for the unique_for_. date_checks = [] # Gather a list of checks for fields declared as unique and add them to # the list of checks. fields_with_class = [(self.__class__, self._meta.local_fields)] for parent_class in self._meta.parents.keys(): fields_with_class.append((parent_class, parent_class._meta.local_fields)) for model_class, fields in fields_with_class: for f in fields: name = f.name if name in exclude: continue if f.unique: unique_checks.append((model_class, (name,))) if f.unique_for_date and f.unique_for_date not in exclude: date_checks.append((model_class, 'date', name, f.unique_for_date)) if f.unique_for_year and f.unique_for_year not in exclude: date_checks.append((model_class, 'year', name, f.unique_for_year)) if f.unique_for_month and f.unique_for_month not in exclude: date_checks.append((model_class, 'month', name, f.unique_for_month)) return unique_checks, date_checks def _perform_unique_checks(self, unique_checks): errors = {} for model_class, unique_check in unique_checks: # Try to look up an existing object with the same values as this # object's values for all the unique field. lookup_kwargs = {} for field_name in unique_check: f = self._meta.get_field(field_name) lookup_value = getattr(self, f.attname) if lookup_value is None: # no value, skip the lookup continue if f.primary_key and not self._state.adding: # no need to check for unique primary key when editing continue lookup_kwargs[str(field_name)] = lookup_value # some fields were skipped, no reason to do the check if len(unique_check) != len(lookup_kwargs): continue qs = model_class._default_manager.filter(**lookup_kwargs) # Exclude the current object from the query if we are editing an # instance (as opposed to creating a new one) # Note that we need to use the pk as defined by model_class, not # self.pk. These can be different fields because model inheritance # allows single model to have effectively multiple primary keys. # Refs #17615. model_class_pk = self._get_pk_val(model_class._meta) if not self._state.adding and model_class_pk is not None: qs = qs.exclude(pk=model_class_pk) if qs.exists(): if len(unique_check) == 1: key = unique_check[0] else: key = NON_FIELD_ERRORS errors.setdefault(key, []).append(self.unique_error_message(model_class, unique_check)) return errors def _perform_date_checks(self, date_checks): errors = {} for model_class, lookup_type, field, unique_for in date_checks: lookup_kwargs = {} # there's a ticket to add a date lookup, we can remove this special # case if that makes it's way in date = getattr(self, unique_for) if date is None: continue if lookup_type == 'date': lookup_kwargs['%s__day' % unique_for] = date.day lookup_kwargs['%s__month' % unique_for] = date.month lookup_kwargs['%s__year' % unique_for] = date.year else: lookup_kwargs['%s__%s' % (unique_for, lookup_type)] = getattr(date, lookup_type) lookup_kwargs[field] = getattr(self, field) qs = model_class._default_manager.filter(**lookup_kwargs) # Exclude the current object from the query if we are editing an # instance (as opposed to creating a new one) if not self._state.adding and self.pk is not None: qs = qs.exclude(pk=self.pk) if qs.exists(): errors.setdefault(field, []).append( self.date_error_message(lookup_type, field, unique_for) ) return errors def date_error_message(self, lookup_type, field, 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 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 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 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) ############################################ # HELPER FUNCTIONS (CURRIED MODEL METHODS) # ############################################ # ORDERING METHODS ######################### def method_set_order(ordered_obj, self, id_list, using=None): if using is None: using = DEFAULT_DB_ALIAS rel_val = getattr(self, ordered_obj._meta.order_with_respect_to.rel.field_name) order_name = ordered_obj._meta.order_with_respect_to.name # FIXME: It would be nice if there was an "update many" version of update # for situations like this. with transaction.commit_on_success_unless_managed(using=using): for i, j in enumerate(id_list): ordered_obj.objects.filter(**{'pk': j, order_name: rel_val}).update(_order=i) def method_get_order(ordered_obj, self): rel_val = getattr(self, ordered_obj._meta.order_with_respect_to.rel.field_name) order_name = ordered_obj._meta.order_with_respect_to.name pk_name = ordered_obj._meta.pk.name return [r[pk_name] for r in ordered_obj.objects.filter(**{order_name: rel_val}).values(pk_name)] ############################################## # HELPER FUNCTIONS (CURRIED MODEL FUNCTIONS) # ############################################## def get_absolute_url(opts, func, self, *args, **kwargs): return settings.ABSOLUTE_URL_OVERRIDES.get('%s.%s' % (opts.app_label, opts.model_name), func)(self, *args, **kwargs) ######## # MISC # ######## def simple_class_factory(model, attrs): """ Needed for dynamic classes. """ return model def model_unpickle(model_id, attrs, factory): """ Used to unpickle Model subclasses with deferred fields. """ if isinstance(model_id, tuple): model = get_model(*model_id) else: # Backwards compat - the model was cached directly in earlier versions. model = model_id cls = factory(model, attrs) return cls.__new__(cls) model_unpickle.__safe_for_unpickle__ = True def unpickle_inner_exception(klass, exception_name): # Get the exception class from the class it is attached to: exception = getattr(klass, exception_name) return exception.__new__(exception)