blinkster: comparison web/lib/django/db/models/options.py

equal deleted inserted replaced

-:8d941af65caf
+:77b6da96e6f1
+import re
+from bisect import bisect
+from django.conf import settings
+from django.db.models.related import RelatedObject
+from django.db.models.fields.related import ManyToManyRel
+from django.db.models.fields import AutoField, FieldDoesNotExist
+from django.db.models.fields.proxy import OrderWrt
+from django.db.models.loading import get_models, app_cache_ready
+from django.utils.translation import activate, deactivate_all, get_language, string_concat
+from django.utils.encoding import force_unicode, smart_str
+from django.utils.datastructures import SortedDict
+# Calculate the verbose_name by converting from InitialCaps to "lowercase with spaces".
+get_verbose_name = lambda class_name: re.sub('(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))', ' \\1', class_name).lower().strip()
+DEFAULT_NAMES = ('verbose_name', 'db_table', 'ordering',
+'unique_together', 'permissions', 'get_latest_by',
+'order_with_respect_to', 'app_label', 'db_tablespace',
+'abstract', 'managed', 'proxy', 'auto_created')
+class Options(object):
+def __init__(self, meta, app_label=None):
+self.local_fields, self.local_many_to_many = [], []
+self.virtual_fields = []
+self.module_name, self.verbose_name = None, None
+self.verbose_name_plural = None
+self.db_table = ''
+self.ordering = []
+self.unique_together =  []
+self.permissions =  []
+self.object_name, self.app_label = None, app_label
+self.get_latest_by = None
+self.order_with_respect_to = None
+self.db_tablespace = settings.DEFAULT_TABLESPACE
+self.admin = None
+self.meta = meta
+self.pk = None
+self.has_auto_field, self.auto_field = False, None
+self.abstract = False
+self.managed = True
+self.proxy = False
+self.proxy_for_model = None
+self.parents = SortedDict()
+self.duplicate_targets = {}
+self.auto_created = False
+# To handle various inheritance situations, we need to track where
+# managers came from (concrete or abstract base classes).
+self.abstract_managers = []
+self.concrete_managers = []
+def contribute_to_class(self, cls, name):
+from django.db import connection
+from django.db.backends.util import truncate_name
+cls._meta = self
+self.installed = re.sub('\.models$', '', cls.__module__) in settings.INSTALLED_APPS
+# First, construct the default values for these options.
+self.object_name = cls.__name__
+self.module_name = self.object_name.lower()
+self.verbose_name = get_verbose_name(self.object_name)
+# Next, apply any overridden values from 'class Meta'.
+if self.meta:
+meta_attrs = self.meta.__dict__.copy()
+for name in self.meta.__dict__:
+# Ignore any private attributes that Django doesn't care about.
+# NOTE: We can't modify a dictionary's contents while looping
+# over it, so we loop over the *original* dictionary instead.
+if name.startswith('_'):
+del meta_attrs[name]
+for attr_name in DEFAULT_NAMES:
+if attr_name in meta_attrs:
+setattr(self, attr_name, meta_attrs.pop(attr_name))
+elif hasattr(self.meta, attr_name):
+setattr(self, attr_name, getattr(self.meta, attr_name))
+# unique_together can be either a tuple of tuples, or a single
+# tuple of two strings. Normalize it to a tuple of tuples, so that
+# calling code can uniformly expect that.
+ut = meta_attrs.pop('unique_together', getattr(self, 'unique_together'))
+if ut and not isinstance(ut[0], (tuple, list)):
+ut = (ut,)
+setattr(self, 'unique_together', ut)
+# verbose_name_plural is a special case because it uses a 's'
+# by default.
+setattr(self, 'verbose_name_plural', meta_attrs.pop('verbose_name_plural', string_concat(self.verbose_name, 's')))
+# Any leftover attributes must be invalid.
+if meta_attrs != {}:
+raise TypeError("'class Meta' got invalid attribute(s): %s" % ','.join(meta_attrs.keys()))
+else:
+self.verbose_name_plural = string_concat(self.verbose_name, 's')
+del self.meta
+# If the db_table wasn't provided, use the app_label + module_name.
+if not self.db_table:
+self.db_table = "%s_%s" % (self.app_label, self.module_name)
+self.db_table = truncate_name(self.db_table, connection.ops.max_name_length())
+def _prepare(self, model):
+if self.order_with_respect_to:
+self.order_with_respect_to = self.get_field(self.order_with_respect_to)
+self.ordering = ('_order',)
+model.add_to_class('_order', OrderWrt())
+else:
+self.order_with_respect_to = None
+if self.pk is None:
+if self.parents:
+# Promote the first parent link in lieu of adding yet another
+# field.
+field = self.parents.value_for_index(0)
+field.primary_key = True
+self.setup_pk(field)
+else:
+auto = AutoField(verbose_name='ID', primary_key=True,
+auto_created=True)
+model.add_to_class('id', auto)
+# Determine any sets of fields that are pointing to the same targets
+# (e.g. two ForeignKeys to the same remote model). The query
+# construction code needs to know this. At the end of this,
+# self.duplicate_targets will map each duplicate field column to the
+# columns it duplicates.
+collections = {}
+for column, target in self.duplicate_targets.iteritems():
+try:
+collections[target].add(column)
+except KeyError:
+collections[target] = set([column])
+self.duplicate_targets = {}
+for elt in collections.itervalues():
+if len(elt) == 1:
+continue
+for column in elt:
+self.duplicate_targets[column] = elt.difference(set([column]))
+def add_field(self, field):
+# Insert the given field in the order in which it was created, using
+# the "creation_counter" attribute of the field.
+# Move many-to-many related fields from self.fields into
+# self.many_to_many.
+if field.rel and isinstance(field.rel, ManyToManyRel):
+self.local_many_to_many.insert(bisect(self.local_many_to_many, field), field)
+if hasattr(self, '_m2m_cache'):
+del self._m2m_cache
+else:
+self.local_fields.insert(bisect(self.local_fields, field), field)
+self.setup_pk(field)
+if hasattr(self, '_field_cache'):
+del self._field_cache
+del self._field_name_cache
+if hasattr(self, '_name_map'):
+del self._name_map
+def add_virtual_field(self, field):
+self.virtual_fields.append(field)
+def setup_pk(self, field):
+if not self.pk and field.primary_key:
+self.pk = field
+field.serialize = False
+def setup_proxy(self, target):
+"""
+Does the internal setup so that the current model is a proxy for
+"target".
+"""
+self.pk = target._meta.pk
+self.proxy_for_model = target
+self.db_table = target._meta.db_table
+def __repr__(self):
+return '<Options for %s>' % self.object_name
+def __str__(self):
+return "%s.%s" % (smart_str(self.app_label), smart_str(self.module_name))
+def verbose_name_raw(self):
+"""
+There are a few places where the untranslated verbose name is needed
+(so that we get the same value regardless of currently active
+locale).
+"""
+lang = get_language()
+deactivate_all()
+raw = force_unicode(self.verbose_name)
+activate(lang)
+return raw
+verbose_name_raw = property(verbose_name_raw)
+def _fields(self):
+"""
+The getter for self.fields. This returns the list of field objects
+available to this model (including through parent models).
+Callers are not permitted to modify this list, since it's a reference
+to this instance (not a copy).
+"""
+try:
+self._field_name_cache
+except AttributeError:
+self._fill_fields_cache()
+return self._field_name_cache
+fields = property(_fields)
+def get_fields_with_model(self):
+"""
+Returns a sequence of (field, model) pairs for all fields. The "model"
+element is None for fields on the current model. Mostly of use when
+constructing queries so that we know which model a field belongs to.
+"""
+try:
+self._field_cache
+except AttributeError:
+self._fill_fields_cache()
+return self._field_cache
+def _fill_fields_cache(self):
+cache = []
+for parent in self.parents:
+for field, model in parent._meta.get_fields_with_model():
+if model:
+cache.append((field, model))
+else:
+cache.append((field, parent))
+cache.extend([(f, None) for f in self.local_fields])
+self._field_cache = tuple(cache)
+self._field_name_cache = [x for x, _ in cache]
+def _many_to_many(self):
+try:
+self._m2m_cache
+except AttributeError:
+self._fill_m2m_cache()
+return self._m2m_cache.keys()
+many_to_many = property(_many_to_many)
+def get_m2m_with_model(self):
+"""
+The many-to-many version of get_fields_with_model().
+"""
+try:
+self._m2m_cache
+except AttributeError:
+self._fill_m2m_cache()
+return self._m2m_cache.items()
+def _fill_m2m_cache(self):
+cache = SortedDict()
+for parent in self.parents:
+for field, model in parent._meta.get_m2m_with_model():
+if model:
+cache[field] = model
+else:
+cache[field] = parent
+for field in self.local_many_to_many:
+cache[field] = None
+self._m2m_cache = cache
+def get_field(self, name, many_to_many=True):
+"""
+Returns the requested field by name. Raises FieldDoesNotExist on error.
+"""
+to_search = many_to_many and (self.fields + self.many_to_many) or self.fields
+for f in to_search:
+if f.name == name:
+return f
+raise FieldDoesNotExist('%s has no field named %r' % (self.object_name, name))
+def get_field_by_name(self, name):
+"""
+Returns the (field_object, model, direct, m2m), where field_object is
+the Field instance for the given name, model is the model containing
+this field (None for local fields), direct is True if the field exists
+on this model, and m2m is True for many-to-many relations. When
+'direct' is False, 'field_object' is the corresponding RelatedObject
+for this field (since the field doesn't have an instance associated
+with it).
+Uses a cache internally, so after the first access, this is very fast.
+"""
+try:
+try:
+return self._name_map[name]
+except AttributeError:
+cache = self.init_name_map()
+return cache[name]
+except KeyError:
+raise FieldDoesNotExist('%s has no field named %r'
+% (self.object_name, name))
+def get_all_field_names(self):
+"""
+Returns a list of all field names that are possible for this model
+(including reverse relation names). This is used for pretty printing
+debugging output (a list of choices), so any internal-only field names
+are not included.
+"""
+try:
+cache = self._name_map
+except AttributeError:
+cache = self.init_name_map()
+names = cache.keys()
+names.sort()
+# Internal-only names end with "+" (symmetrical m2m related names being
+# the main example). Trim them.
+return [val for val in names if not val.endswith('+')]
+def init_name_map(self):
+"""
+Initialises the field name -> field object mapping.
+"""
+cache = {}
+# We intentionally handle related m2m objects first so that symmetrical
+# m2m accessor names can be overridden, if necessary.
+for f, model in self.get_all_related_m2m_objects_with_model():
+cache[f.field.related_query_name()] = (f, model, False, True)
+for f, model in self.get_all_related_objects_with_model():
+cache[f.field.related_query_name()] = (f, model, False, False)
+for f, model in self.get_m2m_with_model():
+cache[f.name] = (f, model, True, True)
+for f, model in self.get_fields_with_model():
+cache[f.name] = (f, model, True, False)
+if app_cache_ready():
+self._name_map = cache
+return cache
+def get_add_permission(self):
+return 'add_%s' % self.object_name.lower()
+def get_change_permission(self):
+return 'change_%s' % self.object_name.lower()
+def get_delete_permission(self):
+return 'delete_%s' % self.object_name.lower()
+def get_all_related_objects(self, local_only=False):
+try:
+self._related_objects_cache
+except AttributeError:
+self._fill_related_objects_cache()
+if local_only:
+return [k for k, v in self._related_objects_cache.items() if not v]
+return self._related_objects_cache.keys()
+def get_all_related_objects_with_model(self):
+"""
+Returns a list of (related-object, model) pairs. Similar to
+get_fields_with_model().
+"""
+try:
+self._related_objects_cache
+except AttributeError:
+self._fill_related_objects_cache()
+return self._related_objects_cache.items()
+def _fill_related_objects_cache(self):
+cache = SortedDict()
+parent_list = self.get_parent_list()
+for parent in self.parents:
+for obj, model in parent._meta.get_all_related_objects_with_model():
+if (obj.field.creation_counter < 0 or obj.field.rel.parent_link) and obj.model not in parent_list:
+continue
+if not model:
+cache[obj] = parent
+else:
+cache[obj] = model
+for klass in get_models():
+for f in klass._meta.local_fields:
+if f.rel and not isinstance(f.rel.to, str) and self == f.rel.to._meta:
+cache[RelatedObject(f.rel.to, klass, f)] = None
+self._related_objects_cache = cache
+def get_all_related_many_to_many_objects(self, local_only=False):
+try:
+cache = self._related_many_to_many_cache
+except AttributeError:
+cache = self._fill_related_many_to_many_cache()
+if local_only:
+return [k for k, v in cache.items() if not v]
+return cache.keys()
+def get_all_related_m2m_objects_with_model(self):
+"""
+Returns a list of (related-m2m-object, model) pairs. Similar to
+get_fields_with_model().
+"""
+try:
+cache = self._related_many_to_many_cache
+except AttributeError:
+cache = self._fill_related_many_to_many_cache()
+return cache.items()
+def _fill_related_many_to_many_cache(self):
+cache = SortedDict()
+parent_list = self.get_parent_list()
+for parent in self.parents:
+for obj, model in parent._meta.get_all_related_m2m_objects_with_model():
+if obj.field.creation_counter < 0 and obj.model not in parent_list:
+continue
+if not model:
+cache[obj] = parent
+else:
+cache[obj] = model
+for klass in get_models():
+for f in klass._meta.local_many_to_many:
+if f.rel and not isinstance(f.rel.to, str) and self == f.rel.to._meta:
+cache[RelatedObject(f.rel.to, klass, f)] = None
+if app_cache_ready():
+self._related_many_to_many_cache = cache
+return cache
+def get_base_chain(self, model):
+"""
+Returns a list of parent classes leading to 'model' (order from closet
+to most distant ancestor). This has to handle the case were 'model' is
+a granparent or even more distant relation.
+"""
+if not self.parents:
+return
+if model in self.parents:
+return [model]
+for parent in self.parents:
+res = parent._meta.get_base_chain(model)
+if res:
+res.insert(0, parent)
+return res
+raise TypeError('%r is not an ancestor of this model'
+% model._meta.module_name)
+def get_parent_list(self):
+"""
+Returns a list of all the ancestor of this model as a list. Useful for
+determining if something is an ancestor, regardless of lineage.
+"""
+result = set()
+for parent in self.parents:
+result.add(parent)
+result.update(parent._meta.get_parent_list())
+return result
+def get_ancestor_link(self, ancestor):
+"""
+Returns the field on the current model which points to the given
+"ancestor". This is possible an indirect link (a pointer to a parent
+model, which points, eventually, to the ancestor). Used when
+constructing table joins for model inheritance.
+Returns None if the model isn't an ancestor of this one.
+"""
+if ancestor in self.parents:
+return self.parents[ancestor]
+for parent in self.parents:
+# Tries to get a link field from the immediate parent
+parent_link = parent._meta.get_ancestor_link(ancestor)
+if parent_link:
+# In case of a proxied model, the first link
+# of the chain to the ancestor is that parent
+# links
+return self.parents[parent] or parent_link
+def get_ordered_objects(self):
+"Returns a list of Options objects that are ordered with respect to this object."
+if not hasattr(self, '_ordered_objects'):
+objects = []
+# TODO
+#for klass in get_models(get_app(self.app_label)):
+#    opts = klass._meta
+#    if opts.order_with_respect_to and opts.order_with_respect_to.rel \
+#        and self == opts.order_with_respect_to.rel.to._meta:
+#        objects.append(opts)
+self._ordered_objects = objects
+return self._ordered_objects
+def pk_index(self):
+"""
+Returns the index of the primary key field in the self.fields list.
+"""
+return self.fields.index(self.pk)