Index: django/db/models/fields/related.py =================================================================== --- django/db/models/fields/related.py (revision 7003) +++ django/db/models/fields/related.py (working copy) @@ -54,6 +54,21 @@ except klass.DoesNotExist: raise validators.ValidationError, _("Please enter a valid %s.") % f.verbose_name +def get_reverse_rel_field(from_model, to_model, related_name): + "Gets the related field which points from one model to another." + for field in from_model._meta.fields: + if field.__class__ == ForeignKey: + if field.rel.to == to_model: + return field + return None + +def get_model_for_db_table(db_table): + "Gets a model class from a db_table string." + for model in get_models(): + if model._meta.db_table == db_table: + return model + return None + #HACK class RelatedField(object): def contribute_to_class(self, cls, name): @@ -267,7 +282,8 @@ and adds behavior for many-to-many related objects.""" class ManyRelatedManager(superclass): def __init__(self, model=None, core_filters=None, instance=None, symmetrical=None, - join_table=None, source_col_name=None, target_col_name=None): + join_table=None, source_col_name=None, target_col_name=None, + through=None): super(ManyRelatedManager, self).__init__() self.core_filters = core_filters self.model = model @@ -276,6 +292,7 @@ self.join_table = join_table self.source_col_name = source_col_name self.target_col_name = target_col_name + self.through = through self._pk_val = self.instance._get_pk_val() if self._pk_val is None: raise ValueError("%r instance needs to have a primary key value before a many-to-many relationship can be used." % model) @@ -284,6 +301,8 @@ return superclass.get_query_set(self).filter(**(self.core_filters)) def add(self, *objs): + if self.through: + raise NotImplementedError, "Add not possible for ManyToManyFields which specify a through model. Try %s.objects.create(...) instead." % self.through self._add_items(self.source_col_name, self.target_col_name, *objs) # If this is a symmetrical m2m relation to self, add the mirror entry in the m2m table @@ -292,8 +311,10 @@ add.alters_data = True def remove(self, *objs): + if self.through: + raise NotImplementedError, "Remove not possible for ManyToManyFields which specify a through model." self._remove_items(self.source_col_name, self.target_col_name, *objs) - + # If this is a symmetrical m2m relation to self, remove the mirror entry in the m2m table if self.symmetrical: self._remove_items(self.target_col_name, self.source_col_name, *objs) @@ -405,7 +426,8 @@ symmetrical=False, join_table=qn(self.related.field.m2m_db_table()), source_col_name=qn(self.related.field.m2m_reverse_name()), - target_col_name=qn(self.related.field.m2m_column_name()) + target_col_name=qn(self.related.field.m2m_column_name()), + through=getattr(self.related.field.rel, 'through', None) ) return manager @@ -414,6 +436,10 @@ if instance is None: raise AttributeError, "Manager must be accessed via instance" + through = getattr(self.related.field.rel, 'through', None) + if through: + raise NotImplementedError, "Cannot set values on a ManyToManyFields which specify a through model. Use %s's Manager instead." % through + manager = self.__get__(instance) manager.clear() manager.add(*value) @@ -446,7 +472,8 @@ symmetrical=(self.field.rel.symmetrical and instance.__class__ == rel_model), join_table=qn(self.field.m2m_db_table()), source_col_name=qn(self.field.m2m_column_name()), - target_col_name=qn(self.field.m2m_reverse_name()) + target_col_name=qn(self.field.m2m_reverse_name()), + through=getattr(self.field.rel, 'through', None) ) return manager @@ -455,6 +482,10 @@ if instance is None: raise AttributeError, "Manager must be accessed via instance" + through = getattr(self.field.rel, 'through', None) + if through: + raise NotImplementedError, "Cannot set values on a ManyToManyFields which specify a through model. Use %s's Manager instead." % through + manager = self.__get__(instance) manager.clear() manager.add(*value) @@ -648,8 +679,11 @@ filter_interface=kwargs.pop('filter_interface', None), limit_choices_to=kwargs.pop('limit_choices_to', None), raw_id_admin=kwargs.pop('raw_id_admin', False), - symmetrical=kwargs.pop('symmetrical', True)) + symmetrical=kwargs.pop('symmetrical', True), + through=kwargs.pop('through', None)) self.db_table = kwargs.pop('db_table', None) + if kwargs['rel'].through: + assert not self.db_table, "Cannot specify a db_table if an intermediary model is used." if kwargs["rel"].raw_id_admin: kwargs.setdefault("validator_list", []).append(self.isValidIDList) Field.__init__(self, **kwargs) @@ -672,7 +706,9 @@ def _get_m2m_db_table(self, opts): "Function that can be curried to provide the m2m table name for this relation" - if self.db_table: + if self.rel.through != None: + return get_model(opts.app_label, self.rel.through)._meta.db_table + elif self.db_table: return self.db_table else: return '%s_%s' % (opts.db_table, self.name) @@ -680,7 +716,12 @@ def _get_m2m_column_name(self, related): "Function that can be curried to provide the source column name for the m2m table" # If this is an m2m relation to self, avoid the inevitable name clash - if related.model == related.parent_model: + if self.rel.through != None: + through = get_model(related.opts.app_label, self.rel.through) + field = get_reverse_rel_field(through, related.model, self.rel.related_name) + attname, column = field.get_attname_column() + return column + elif related.model == related.parent_model: return 'from_' + related.model._meta.object_name.lower() + '_id' else: return related.model._meta.object_name.lower() + '_id' @@ -688,7 +729,12 @@ def _get_m2m_reverse_name(self, related): "Function that can be curried to provide the related column name for the m2m table" # If this is an m2m relation to self, avoid the inevitable name clash - if related.model == related.parent_model: + if self.rel.through != None: + through = get_model(related.opts.app_label, self.rel.through) + field = get_reverse_rel_field(through, related.parent_model, self.rel.related_name) + attname, column = field.get_attname_column() + return column + elif related.model == related.parent_model: return 'to_' + related.parent_model._meta.object_name.lower() + '_id' else: return related.parent_model._meta.object_name.lower() + '_id' @@ -809,7 +855,8 @@ class ManyToManyRel(object): def __init__(self, to, num_in_admin=0, related_name=None, - filter_interface=None, limit_choices_to=None, raw_id_admin=False, symmetrical=True): + filter_interface=None, limit_choices_to=None, raw_id_admin=False, symmetrical=True, + through = None): self.to = to self.num_in_admin = num_in_admin self.related_name = related_name @@ -821,5 +868,6 @@ self.raw_id_admin = raw_id_admin self.symmetrical = symmetrical self.multiple = True + self.through = through assert not (self.raw_id_admin and self.filter_interface), "ManyToManyRels may not use both raw_id_admin and filter_interface" Index: django/core/management/validation.py =================================================================== --- django/core/management/validation.py (revision 7003) +++ django/core/management/validation.py (working copy) @@ -104,6 +104,8 @@ if r.get_accessor_name() == rel_query_name: e.add(opts, "Reverse query name for field '%s' clashes with related field '%s.%s'. Add a related_name argument to the definition for '%s'." % (f.name, rel_opts.object_name, r.get_accessor_name(), f.name)) + seen_intermediary_signatures = [] + for i, f in enumerate(opts.many_to_many): # Check to see if the related m2m field will clash with any # existing fields, m2m fields, m2m related objects or related objects @@ -113,6 +115,28 @@ # so skip the next section if isinstance(f.rel.to, (str, unicode)): continue + if hasattr(f.rel, 'through') and f.rel.through != None: + intermediary_model = None + for model in models.get_models(): + if model._meta.module_name == f.rel.through.lower(): + intermediary_model = model + if intermediary_model == None: + e.add(opts, "%s has a manually-defined m2m relationship through a model (%s) which does not exist." % (f.name, f.rel.through)) + else: + signature = (f.rel.to, cls, intermediary_model) + if signature in seen_intermediary_signatures: + e.add(opts, "%s has two manually defined m2m relationships through the same model (%s), which is not possible. Please use a field on your intermediary model instead." % (cls._meta.object_name, intermediary_model._meta.object_name)) + else: + seen_intermediary_signatures.append(signature) + seen_related_fk, seen_this_fk = False, False + for field in intermediary_model._meta.fields: + if field.rel: + if field.rel.to == f.rel.to: + seen_related_fk = True + elif field.rel.to == cls: + seen_this_fk = True + if not seen_related_fk or not seen_this_fk: + e.add(opts, "%s has a manualy-defined m2m relationship through a model (%s) which does not have foreign keys to %s and %s" % (f.name, f.rel.through, f.rel.to._meta.object_name, cls._meta.object_name)) rel_opts = f.rel.to._meta rel_name = RelatedObject(f.rel.to, cls, f).get_accessor_name() Index: django/core/management/sql.py =================================================================== --- django/core/management/sql.py (revision 7003) +++ django/core/management/sql.py (working copy) @@ -352,7 +352,7 @@ qn = connection.ops.quote_name inline_references = connection.features.inline_fk_references for f in opts.many_to_many: - if not isinstance(f.rel, generic.GenericRel): + if not isinstance(f.rel, generic.GenericRel) and getattr(f.rel, 'through', None) == None: tablespace = f.db_tablespace or opts.db_tablespace if tablespace and connection.features.supports_tablespaces and connection.features.autoindexes_primary_keys: tablespace_sql = ' ' + connection.ops.tablespace_sql(tablespace, inline=True) Index: tests/modeltests/invalid_models/models.py =================================================================== --- tests/modeltests/invalid_models/models.py (revision 7003) +++ tests/modeltests/invalid_models/models.py (working copy) @@ -111,7 +111,32 @@ class MissingRelations(models.Model): rel1 = models.ForeignKey("Rel1") rel2 = models.ManyToManyField("Rel2") + +class MissingManualM2MModel(models.Model): + name = models.CharField(max_length=5) + missing_m2m = models.ManyToManyField(Model, through="MissingM2MModel") + +class Person(models.Model): + name = models.CharField(max_length=5) +class Group(models.Model): + name = models.CharField(max_length=5) + primary = models.ManyToManyField(Person, through="Membership", related_name="primary") + secondary = models.ManyToManyField(Person, through="Membership", related_name="secondary") + +class GroupTwo(models.Model): + name = models.CharField(max_length=5) + primary = models.ManyToManyField(Person, through="Membership") + secondary = models.ManyToManyField(Group, through="MembershipMissingFK") + +class Membership(models.Model): + person = models.ForeignKey(Person) + group = models.ForeignKey(Group) + not_default_or_null = models.CharField(max_length=5) + +class MembershipMissingFK(models.Model): + person = models.ForeignKey(Person) + model_errors = """invalid_models.fielderrors: "charfield": CharFields require a "max_length" attribute. invalid_models.fielderrors: "decimalfield": DecimalFields require a "decimal_places" attribute. invalid_models.fielderrors: "decimalfield": DecimalFields require a "max_digits" attribute. @@ -197,4 +222,8 @@ invalid_models.selfclashm2m: Reverse query name for m2m field 'm2m_4' clashes with field 'SelfClashM2M.selfclashm2m'. Add a related_name argument to the definition for 'm2m_4'. invalid_models.missingrelations: 'rel2' has m2m relation with model Rel2, which has not been installed invalid_models.missingrelations: 'rel1' has relation with model Rel1, which has not been installed +invalid_models.group: Group has two manually defined m2m relationships through the same model (Membership), which is not possible. Please use a field on your intermediary model instead. +invalid_models.missingmanualm2mmodel: missing_m2m has a manually-defined m2m relationship through a model (MissingM2MModel) which does not exist. +invalid_models.grouptwo: primary has a manualy-defined m2m relationship through a model (Membership) which does not have foreign keys to Person and GroupTwo +invalid_models.grouptwo: secondary has a manualy-defined m2m relationship through a model (MembershipMissingFK) which does not have foreign keys to Group and GroupTwo """ Index: tests/modeltests/m2m_manual/__init__.py =================================================================== Index: tests/modeltests/m2m_manual/models.py =================================================================== --- tests/modeltests/m2m_manual/models.py (revision 0) +++ tests/modeltests/m2m_manual/models.py (revision 0) @@ -0,0 +1,227 @@ +from django.db import models +from datetime import datetime + +# M2M described on one of the models +class Person(models.Model): + name = models.CharField(max_length=128) + + def __unicode__(self): + return self.name + +class Group(models.Model): + name = models.CharField(max_length=128) + members = models.ManyToManyField(Person, through='Membership') + custom_members = models.ManyToManyField(Person, through='CustomMembership', related_name="custom") + nodefaultsnonulls = models.ManyToManyField(Person, through='TestNoDefaultsOrNulls', related_name="testnodefaultsnonulls") + + def __unicode__(self): + return self.name + +class Membership(models.Model): + person = models.ForeignKey(Person) + group = models.ForeignKey(Group) + date_joined = models.DateTimeField(default=datetime.now) + invite_reason = models.CharField(max_length=64, null=True) + + def __unicode__(self): + return "%s is a member of %s" % (self.person.name, self.group.name) + +class CustomMembership(models.Model): + person = models.ForeignKey(Person, db_column="custom_person_column", related_name="custom_person_related_name") + group = models.ForeignKey(Group) + weird_fk = models.ForeignKey(Membership, null=True) + date_joined = models.DateTimeField(default=datetime.now) + + def __unicode__(self): + return "%s is a member of %s" % (self.person.name, self.group.name) + + class Meta: + db_table = "test_table" + +class TestNoDefaultsOrNulls(models.Model): + person = models.ForeignKey(Person) + group = models.ForeignKey(Group) + nodefaultnonull = models.CharField(max_length=5) + +__test__ = {'API_TESTS':""" +>>> from datetime import datetime + +### Creation and Saving Tests ### +>>> bob = Person.objects.create(name = 'Bob') +>>> jim = Person.objects.create(name = 'Jim') +>>> jane = Person.objects.create(name = 'Jane') +>>> rock = Group.objects.create(name = 'Rock') +>>> roll = Group.objects.create(name = 'Roll') + +>>> rock.members.all() +[] + +>>> m1 = Membership.objects.create(person = jim, group = rock) +>>> m2 = Membership.objects.create(person = jane, group = rock) + +>>> rock.members.all() +[, ] + +>>> m3 = Membership.objects.create(person = bob, group = roll) +>>> m4 = Membership.objects.create(person = jim, group = roll) +>>> m5 = Membership.objects.create(person = jane, group = roll) + +>>> jim.group_set.all() +[, ] + +# Check to make sure that querying via intermediary model works as normal +>>> m = Membership.objects.get(person = jane, group = rock) +>>> m + + +# Setting some date_joined dates +>>> m2.invite_reason = "She was just awesome." +>>> m2.date_joined = datetime(2006, 1, 1) +>>> m2.save() + +>>> m5.date_joined = datetime(2004, 1, 1) +>>> m5.save() + +>>> m3.date_joined = datetime(2004, 1, 1) +>>> m3.save() + +>>> Membership.objects.filter(person = jim) +[, ] + + +### Forward Descriptors Tests ### +# Ensure that using the add or remove function errors, due to using a through model. +>>> rock.members.add(bob) +Traceback (most recent call last): +... +NotImplementedError: Add not possible for ManyToManyFields which specify a through model. Try Membership.objects.create(...) instead. + +>>> rock.members.remove(jim) +Traceback (most recent call last): +... +NotImplementedError: Remove not possible for ManyToManyFields which specify a through model. + +>>> backup = list(rock.members.all()) +>>> backup +[, ] + +# The clear function should still work. +>>> rock.members.clear() +>>> rock.members.all() +[] + +# Assignment should not work with models specifying a through model. +>>> rock.members = backup +Traceback (most recent call last): +... +NotImplementedError: Cannot set values on a ManyToManyFields which specify a through model. Use Membership's Manager instead. + +# Let's re-add those instances that we've cleared. +>>> m1.save() +>>> m2.save() + +>>> rock.members.all() +[, ] + + +### Reverse Descriptors Tests ### +# Ensure that using the add or remove function errors, due to using a through model. +>>> bob.group_set.add(rock) +Traceback (most recent call last): +... +NotImplementedError: Add not possible for ManyToManyFields which specify a through model. Try Membership.objects.create(...) instead. + +>>> jim.group_set.remove(rock) +Traceback (most recent call last): +... +NotImplementedError: Remove not possible for ManyToManyFields which specify a through model. + +>>> backup = list(jim.group_set.all()) +>>> backup +[, ] + +# The clear function should still work. +>>> jim.group_set.clear() +>>> jim.group_set.all() +[] + +# Assignment should not work with models specifying a through model. +>>> jim.group_set = backup +Traceback (most recent call last): +... +NotImplementedError: Cannot set values on a ManyToManyFields which specify a through model. Use Membership's Manager instead. + +# Let's re-add those instances that we've cleared. +>>> m1.save() +>>> m4.save() + +>>> jim.group_set.all() +[, ] + +### Custom Tests ### + +>>> rock.custom_members.all() +[] +>>> bob.custom.all() +[] +>>> cm1 = CustomMembership.objects.create(person = bob, group = rock) +>>> cm2 = CustomMembership.objects.create(person = jim, group = rock) + +>>> rock.custom_members.all() +[, ] +>>> bob.custom.all() +[] + +# Let's make sure our new descriptors don't conflict with the FK related_name. +>>> bob.custom_person_related_name.all() +[] + +###QUERY TESTS### +# Queries involving the related model (Person, in the case of Group) use its +# attname +>>> Group.objects.filter(members__name='Bob') +[] + +# Queries involving the relationship model (Membership, in the case of Group) +# use its model name +>>> Group.objects.filter(membership__invite_reason = "She was just awesome.") +[] + +# Queries involving the reverse related model (Group, in the case of Person) +# use its model name +>>> Person.objects.filter(group__name="Rock") +[, ] + +# If the m2m field has specified a related_name, using that will work. +>>> Person.objects.filter(custom__name="Rock") +[, ] + +# Queries involving the relationship model (Membership, in the case of Group) +# use its model name +>>> Person.objects.filter(membership__invite_reason = "She was just awesome.") +[] + +# Let's see all of the groups that Jane joined after 1 Jan 2005: +>>> Group.objects.filter(membership__date_joined__gt = datetime(2005, 1, 1), +... membership__person = jane) +[] + +# Now let's see all of the people that have joined Rock since 1 Jan 2005: +>>> Person.objects.filter(membership__date_joined__gt = datetime(2005, 1, 1), +... membership__group = rock) +[, ] + +# Conceivably, queries through membership could return non-unique querysets. +# To demonstrate this, query for all people who have joined a group after 2004: +>>> Person.objects.filter(membership__date_joined__gt = datetime(2004, 1, 1)) +[, , ] + +# Jim showed up twice, because he joined two groups ('Rock', and 'Roll'): +>>> [(m.person.name, m.group.name) for m in +... Membership.objects.filter(date_joined__gt = datetime(2004, 1, 1))] +[(u'Jim', u'Rock'), (u'Jane', u'Rock'), (u'Jim', u'Roll')] + +# QuerySet's distinct() method can correct this problem. +>>> Person.objects.filter(membership__date_joined__gt = datetime(2004, 1, 1)).distinct() +[, ] +"""} \ No newline at end of file Index: AUTHORS =================================================================== --- AUTHORS (revision 7003) +++ AUTHORS (working copy) @@ -129,6 +129,7 @@ Afonso Fernández Nogueira Matthew Flanagan Eric Floehr + Eric Florenzano Vincent Foley Rudolph Froger Jorge Gajon