diff options
Diffstat (limited to 'activerecord/lib/active_record/associations/association.rb')
-rw-r--r-- | activerecord/lib/active_record/associations/association.rb | 106 |
1 files changed, 77 insertions, 29 deletions
diff --git a/activerecord/lib/active_record/associations/association.rb b/activerecord/lib/active_record/associations/association.rb index ca8c7794e0..cf22b850b9 100644 --- a/activerecord/lib/active_record/associations/association.rb +++ b/activerecord/lib/active_record/associations/association.rb @@ -17,9 +17,25 @@ module ActiveRecord # CollectionAssociation # HasManyAssociation + ForeignAssociation # HasManyThroughAssociation + ThroughAssociation + # + # Associations in Active Record are middlemen between the object that + # holds the association, known as the <tt>owner</tt>, and the associated + # result set, known as the <tt>target</tt>. Association metadata is available in + # <tt>reflection</tt>, which is an instance of <tt>ActiveRecord::Reflection::AssociationReflection</tt>. + # + # For example, given + # + # class Blog < ActiveRecord::Base + # has_many :posts + # end + # + # blog = Blog.first + # + # The association of <tt>blog.posts</tt> has the object +blog+ as its + # <tt>owner</tt>, the collection of its posts as <tt>target</tt>, and + # the <tt>reflection</tt> object represents a <tt>:has_many</tt> macro. class Association #:nodoc: attr_reader :owner, :target, :reflection - attr_accessor :inversed delegate :options, to: :reflection @@ -41,7 +57,9 @@ module ActiveRecord end # Reloads the \target and returns +self+ on success. - def reload + # The QueryCache is cleared if +force+ is true. + def reload(force = false) + klass.connection.clear_query_cache if force && klass reset reset_scope load_target @@ -67,7 +85,7 @@ module ActiveRecord # # Note that if the target has not been loaded, it is not considered stale. def stale_target? - !inversed && loaded? && @stale_state != stale_state + !@inversed && loaded? && @stale_state != stale_state end # Sets the target of this association to <tt>\target</tt>, and the \loaded flag to +true+. @@ -80,53 +98,44 @@ module ActiveRecord target_scope.merge!(association_scope) end - # The scope for this association. - # - # Note that the association_scope is merged into the target_scope only when the - # scope method is called. This is because at that point the call may be surrounded - # by scope.scoping { ... } or with_scope { ... } etc, which affects the scope which - # actually gets built. - def association_scope - if klass - @association_scope ||= AssociationScope.scope(self) - end - end - def reset_scope @association_scope = nil end # Set the inverse association, if possible def set_inverse_instance(record) - if invertible_for?(record) - inverse = record.association(inverse_reflection_for(record).name) - inverse.target = owner - inverse.inversed = true + if inverse = inverse_association_for(record) + inverse.inversed_from(owner) + end + record + end + + def set_inverse_instance_from_queries(record) + if inverse = inverse_association_for(record) + inverse.inversed_from_queries(owner) end record end # Remove the inverse association, if possible def remove_inverse_instance(record) - if invertible_for?(record) - inverse = record.association(inverse_reflection_for(record).name) - inverse.target = nil - inverse.inversed = false + if inverse = inverse_association_for(record) + inverse.inversed_from(nil) end end + def inversed_from(record) + self.target = record + @inversed = !!record + end + alias :inversed_from_queries :inversed_from + # Returns the class of the target. belongs_to polymorphic overrides this to look at the # polymorphic_type field on the owner. def klass reflection.klass end - # Can be overridden (i.e. in ThroughAssociation) to merge in other scopes (i.e. the - # through association's scope) - def target_scope - AssociationRelation.create(klass, self).merge!(klass.all) - end - def extensions extensions = klass.default_extensions | reflection.extensions @@ -187,6 +196,38 @@ module ActiveRecord end private + def find_target + scope = self.scope + return scope.to_a if skip_statement_cache?(scope) + + conn = klass.connection + sc = reflection.association_scope_cache(conn, owner) do |params| + as = AssociationScope.create { params.bind } + target_scope.merge!(as.scope(self)) + end + + binds = AssociationScope.get_bind_values(owner, reflection.chain) + sc.execute(binds, conn) { |record| set_inverse_instance(record) } || [] + end + + # The scope for this association. + # + # Note that the association_scope is merged into the target_scope only when the + # scope method is called. This is because at that point the call may be surrounded + # by scope.scoping { ... } or unscoped { ... } etc, which affects the scope which + # actually gets built. + def association_scope + if klass + @association_scope ||= AssociationScope.scope(self) + end + end + + # Can be overridden (i.e. in ThroughAssociation) to merge in other scopes (i.e. the + # through association's scope) + def target_scope + AssociationRelation.create(klass, self).merge!(klass.scope_for_association) + end + def scope_for_create scope.scope_for_create end @@ -240,6 +281,12 @@ module ActiveRecord end end + def inverse_association_for(record) + if invertible_for?(record) + record.association(inverse_reflection_for(record).name) + end + end + # Can be redefined by subclasses, notably polymorphic belongs_to # The record parameter is necessary to support polymorphic inverses as we must check for # the association in the specific class of the record. @@ -269,6 +316,7 @@ module ActiveRecord def build_record(attributes) reflection.build_association(attributes) do |record| initialize_attributes(record, attributes) + yield(record) if block_given? end end |