1643 lines
88 KiB
Ruby
Executable File
1643 lines
88 KiB
Ruby
Executable File
require 'active_record/associations/association_proxy'
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require 'active_record/associations/association_collection'
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require 'active_record/associations/belongs_to_association'
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require 'active_record/associations/belongs_to_polymorphic_association'
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require 'active_record/associations/has_one_association'
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require 'active_record/associations/has_many_association'
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require 'active_record/associations/has_many_through_association'
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require 'active_record/associations/has_and_belongs_to_many_association'
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require 'active_record/deprecated_associations'
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module ActiveRecord
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class HasManyThroughAssociationNotFoundError < ActiveRecordError #:nodoc:
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def initialize(owner_class_name, reflection)
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super("Could not find the association #{reflection.options[:through].inspect} in model #{owner_class_name}")
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end
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end
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class HasManyThroughAssociationPolymorphicError < ActiveRecordError #:nodoc:
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def initialize(owner_class_name, reflection, source_reflection)
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super("Cannot have a has_many :through association '#{owner_class_name}##{reflection.name}' on the polymorphic object '#{source_reflection.class_name}##{source_reflection.name}'.")
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end
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end
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class HasManyThroughAssociationPointlessSourceTypeError < ActiveRecordError #:nodoc:
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def initialize(owner_class_name, reflection, source_reflection)
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super("Cannot have a has_many :through association '#{owner_class_name}##{reflection.name}' with a :source_type option if the '#{reflection.through_reflection.class_name}##{source_reflection.name}' is not polymorphic. Try removing :source_type on your association.")
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end
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end
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class HasManyThroughSourceAssociationNotFoundError < ActiveRecordError #:nodoc:
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def initialize(reflection)
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through_reflection = reflection.through_reflection
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source_reflection_names = reflection.source_reflection_names
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source_associations = reflection.through_reflection.klass.reflect_on_all_associations.collect { |a| a.name.inspect }
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super("Could not find the source association(s) #{source_reflection_names.collect(&:inspect).to_sentence :connector => 'or'} in model #{through_reflection.klass}. Try 'has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}, :source => <name>'. Is it one of #{source_associations.to_sentence :connector => 'or'}?")
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end
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end
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class HasManyThroughSourceAssociationMacroError < ActiveRecordError #:nodoc:
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def initialize(reflection)
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through_reflection = reflection.through_reflection
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source_reflection = reflection.source_reflection
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super("Invalid source reflection macro :#{source_reflection.macro}#{" :through" if source_reflection.options[:through]} for has_many #{reflection.name.inspect}, :through => #{through_reflection.name.inspect}. Use :source to specify the source reflection.")
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end
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end
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class HasManyThroughCantAssociateNewRecords < ActiveRecordError #:nodoc:
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def initialize(owner, reflection)
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super("Cannot associate new records through '#{owner.class.name}##{reflection.name}' on '#{reflection.source_reflection.class_name rescue nil}##{reflection.source_reflection.name rescue nil}'. Both records must have an id in order to create the has_many :through record associating them.")
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end
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end
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class EagerLoadPolymorphicError < ActiveRecordError #:nodoc:
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def initialize(reflection)
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super("Can not eagerly load the polymorphic association #{reflection.name.inspect}")
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end
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end
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class ReadOnlyAssociation < ActiveRecordError #:nodoc:
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def initialize(reflection)
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super("Can not add to a has_many :through association. Try adding to #{reflection.through_reflection.name.inspect}.")
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end
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end
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module Associations # :nodoc:
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def self.included(base)
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base.extend(ClassMethods)
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end
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# Clears out the association cache
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def clear_association_cache #:nodoc:
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self.class.reflect_on_all_associations.to_a.each do |assoc|
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instance_variable_set "@#{assoc.name}", nil
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end unless self.new_record?
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end
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# Associations are a set of macro-like class methods for tying objects together through foreign keys. They express relationships like
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# "Project has one Project Manager" or "Project belongs to a Portfolio". Each macro adds a number of methods to the class which are
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# specialized according to the collection or association symbol and the options hash. It works much the same way as Ruby's own attr*
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# methods. Example:
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#
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# class Project < ActiveRecord::Base
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# belongs_to :portfolio
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# has_one :project_manager
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# has_many :milestones
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# has_and_belongs_to_many :categories
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# end
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#
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# The project class now has the following methods (and more) to ease the traversal and manipulation of its relationships:
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# * <tt>Project#portfolio, Project#portfolio=(portfolio), Project#portfolio.nil?</tt>
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# * <tt>Project#project_manager, Project#project_manager=(project_manager), Project#project_manager.nil?,</tt>
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# * <tt>Project#milestones.empty?, Project#milestones.size, Project#milestones, Project#milestones<<(milestone),</tt>
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# <tt>Project#milestones.delete(milestone), Project#milestones.find(milestone_id), Project#milestones.find(:all, options),</tt>
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# <tt>Project#milestones.build, Project#milestones.create</tt>
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# * <tt>Project#categories.empty?, Project#categories.size, Project#categories, Project#categories<<(category1),</tt>
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# <tt>Project#categories.delete(category1)</tt>
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#
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# == Example
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#
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# link:files/examples/associations.png
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#
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# == Is it belongs_to or has_one?
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#
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# Both express a 1-1 relationship, the difference is mostly where to place the foreign key, which goes on the table for the class
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# saying belongs_to. Example:
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#
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# class User < ActiveRecord::Base
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# # I reference an account.
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# belongs_to :account
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# end
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#
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# class Account < ActiveRecord::Base
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# # One user references me.
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# has_one :user
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# end
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#
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# The tables for these classes could look something like:
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#
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# CREATE TABLE users (
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# id int(11) NOT NULL auto_increment,
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# account_id int(11) default NULL,
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# name varchar default NULL,
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# PRIMARY KEY (id)
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# )
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#
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# CREATE TABLE accounts (
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# id int(11) NOT NULL auto_increment,
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# name varchar default NULL,
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# PRIMARY KEY (id)
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# )
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#
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# == Unsaved objects and associations
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#
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# You can manipulate objects and associations before they are saved to the database, but there is some special behaviour you should be
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# aware of, mostly involving the saving of associated objects.
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#
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# === One-to-one associations
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#
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# * Assigning an object to a has_one association automatically saves that object and the object being replaced (if there is one), in
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# order to update their primary keys - except if the parent object is unsaved (new_record? == true).
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# * If either of these saves fail (due to one of the objects being invalid) the assignment statement returns false and the assignment
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# is cancelled.
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# * If you wish to assign an object to a has_one association without saving it, use the #association.build method (documented below).
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# * Assigning an object to a belongs_to association does not save the object, since the foreign key field belongs on the parent. It does
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# not save the parent either.
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#
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# === Collections
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#
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# * Adding an object to a collection (has_many or has_and_belongs_to_many) automatically saves that object, except if the parent object
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# (the owner of the collection) is not yet stored in the database.
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# * If saving any of the objects being added to a collection (via #push or similar) fails, then #push returns false.
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# * You can add an object to a collection without automatically saving it by using the #collection.build method (documented below).
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# * All unsaved (new_record? == true) members of the collection are automatically saved when the parent is saved.
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#
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# === Association callbacks
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#
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# Similiar to the normal callbacks that hook into the lifecycle of an Active Record object, you can also define callbacks that get
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# trigged when you add an object to or removing an object from a association collection. Example:
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#
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# class Project
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# has_and_belongs_to_many :developers, :after_add => :evaluate_velocity
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#
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# def evaluate_velocity(developer)
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# ...
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# end
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# end
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#
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# It's possible to stack callbacks by passing them as an array. Example:
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#
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# class Project
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# has_and_belongs_to_many :developers, :after_add => [:evaluate_velocity, Proc.new { |p, d| p.shipping_date = Time.now}]
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# end
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#
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# Possible callbacks are: before_add, after_add, before_remove and after_remove.
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#
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# Should any of the before_add callbacks throw an exception, the object does not get added to the collection. Same with
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# the before_remove callbacks, if an exception is thrown the object doesn't get removed.
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#
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# === Association extensions
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#
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# The proxy objects that controls the access to associations can be extended through anonymous modules. This is especially
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# beneficial for adding new finders, creators, and other factory-type methods that are only used as part of this association.
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# Example:
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#
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# class Account < ActiveRecord::Base
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# has_many :people do
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# def find_or_create_by_name(name)
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# first_name, last_name = name.split(" ", 2)
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# find_or_create_by_first_name_and_last_name(first_name, last_name)
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# end
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# end
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# end
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#
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# person = Account.find(:first).people.find_or_create_by_name("David Heinemeier Hansson")
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# person.first_name # => "David"
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# person.last_name # => "Heinemeier Hansson"
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#
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# If you need to share the same extensions between many associations, you can use a named extension module. Example:
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#
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# module FindOrCreateByNameExtension
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# def find_or_create_by_name(name)
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# first_name, last_name = name.split(" ", 2)
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# find_or_create_by_first_name_and_last_name(first_name, last_name)
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# end
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# end
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#
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# class Account < ActiveRecord::Base
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# has_many :people, :extend => FindOrCreateByNameExtension
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# end
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#
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# class Company < ActiveRecord::Base
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# has_many :people, :extend => FindOrCreateByNameExtension
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# end
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#
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# If you need to use multiple named extension modules, you can specify an array of modules with the :extend option.
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# In the case of name conflicts between methods in the modules, methods in modules later in the array supercede
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# those earlier in the array. Example:
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#
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# class Account < ActiveRecord::Base
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# has_many :people, :extend => [FindOrCreateByNameExtension, FindRecentExtension]
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# end
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#
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# Some extensions can only be made to work with knowledge of the association proxy's internals.
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# Extensions can access relevant state using accessors on the association proxy:
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#
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# * +proxy_owner+ - Returns the object the association is part of.
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# * +proxy_reflection+ - Returns the reflection object that describes the association.
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# * +proxy_target+ - Returns the associated object for belongs_to and has_one, or the collection of associated objects for has_many and has_and_belongs_to_many.
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#
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# === Association Join Models
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#
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# Has Many associations can be configured with the :through option to use an explicit join model to retrieve the data. This
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# operates similarly to a <tt>has_and_belongs_to_many</tt> association. The advantage is that you're able to add validations,
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# callbacks, and extra attributes on the join model. Consider the following schema:
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#
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# class Author < ActiveRecord::Base
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# has_many :authorships
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# has_many :books, :through => :authorships
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# end
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#
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# class Authorship < ActiveRecord::Base
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# belongs_to :author
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# belongs_to :book
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# end
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#
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# @author = Author.find :first
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# @author.authorships.collect { |a| a.book } # selects all books that the author's authorships belong to.
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# @author.books # selects all books by using the Authorship join model
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#
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# You can also go through a has_many association on the join model:
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#
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# class Firm < ActiveRecord::Base
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# has_many :clients
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# has_many :invoices, :through => :clients
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# end
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#
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# class Client < ActiveRecord::Base
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# belongs_to :firm
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# has_many :invoices
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# end
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#
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# class Invoice < ActiveRecord::Base
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# belongs_to :client
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# end
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#
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# @firm = Firm.find :first
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# @firm.clients.collect { |c| c.invoices }.flatten # select all invoices for all clients of the firm
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# @firm.invoices # selects all invoices by going through the Client join model.
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#
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# === Polymorphic Associations
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#
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# Polymorphic associations on models are not restricted on what types of models they can be associated with. Rather, they
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# specify an interface that a has_many association must adhere to.
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#
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# class Asset < ActiveRecord::Base
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# belongs_to :attachable, :polymorphic => true
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# end
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#
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# class Post < ActiveRecord::Base
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# has_many :assets, :as => :attachable # The <tt>:as</tt> option specifies the polymorphic interface to use.
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# end
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#
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# @asset.attachable = @post
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#
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# This works by using a type column in addition to a foreign key to specify the associated record. In the Asset example, you'd need
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# an attachable_id integer column and an attachable_type string column.
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#
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# Using polymorphic associations in combination with single table inheritance (STI) is a little tricky. In order
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# for the associations to work as expected, ensure that you store the base model for the STI models in the
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# type column of the polymorphic association. To continue with the asset example above, suppose there are guest posts
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# and member posts that use the posts table for STI. So there will be an additional 'type' column in the posts table.
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#
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# class Asset < ActiveRecord::Base
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# belongs_to :attachable, :polymorphic => true
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#
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# def attachable_type=(sType)
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# super(sType.to_s.classify.constantize.base_class.to_s)
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# end
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# end
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#
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# class Post < ActiveRecord::Base
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# # because we store "Post" in attachable_type now :dependent => :destroy will work
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# has_many :assets, :as => :attachable, :dependent => :destroy
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# end
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#
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# class GuestPost < ActiveRecord::Base
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# end
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#
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# class MemberPost < ActiveRecord::Base
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# end
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#
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# == Caching
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#
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# All of the methods are built on a simple caching principle that will keep the result of the last query around unless specifically
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# instructed not to. The cache is even shared across methods to make it even cheaper to use the macro-added methods without
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# worrying too much about performance at the first go. Example:
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#
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# project.milestones # fetches milestones from the database
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# project.milestones.size # uses the milestone cache
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# project.milestones.empty? # uses the milestone cache
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# project.milestones(true).size # fetches milestones from the database
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# project.milestones # uses the milestone cache
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#
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# == Eager loading of associations
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#
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# Eager loading is a way to find objects of a certain class and a number of named associations along with it in a single SQL call. This is
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# one of the easiest ways of to prevent the dreaded 1+N problem in which fetching 100 posts that each needs to display their author
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# triggers 101 database queries. Through the use of eager loading, the 101 queries can be reduced to 1. Example:
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#
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# class Post < ActiveRecord::Base
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# belongs_to :author
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# has_many :comments
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# end
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#
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# Consider the following loop using the class above:
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#
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# for post in Post.find(:all)
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# puts "Post: " + post.title
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# puts "Written by: " + post.author.name
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# puts "Last comment on: " + post.comments.first.created_on
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# end
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#
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# To iterate over these one hundred posts, we'll generate 201 database queries. Let's first just optimize it for retrieving the author:
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#
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# for post in Post.find(:all, :include => :author)
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#
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# This references the name of the belongs_to association that also used the :author symbol, so the find will now weave in a join something
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# like this: LEFT OUTER JOIN authors ON authors.id = posts.author_id. Doing so will cut down the number of queries from 201 to 101.
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#
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# We can improve upon the situation further by referencing both associations in the finder with:
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#
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# for post in Post.find(:all, :include => [ :author, :comments ])
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#
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# That'll add another join along the lines of: LEFT OUTER JOIN comments ON comments.post_id = posts.id. And we'll be down to 1 query.
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#
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# To include a deep hierarchy of associations, using a hash:
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#
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# for post in Post.find(:all, :include => [ :author, { :comments => { :author => :gravatar } } ])
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#
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# That'll grab not only all the comments but all their authors and gravatar pictures. You can mix and match
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# symbols, arrays and hashes in any combination to describe the associations you want to load.
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#
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# All of this power shouldn't fool you into thinking that you can pull out huge amounts of data with no performance penalty just because you've reduced
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# the number of queries. The database still needs to send all the data to Active Record and it still needs to be processed. So it's no
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# catch-all for performance problems, but it's a great way to cut down on the number of queries in a situation as the one described above.
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#
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# Since the eager loading pulls from multiple tables, you'll have to disambiguate any column references in both conditions and orders. So
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# :order => "posts.id DESC" will work while :order => "id DESC" will not. Because eager loading generates the SELECT statement too, the
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# :select option is ignored.
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#
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# You can use eager loading on multiple associations from the same table, but you cannot use those associations in orders and conditions
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# as there is currently not any way to disambiguate them. Eager loading will not pull additional attributes on join tables, so "rich
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# associations" with has_and_belongs_to_many are not a good fit for eager loading.
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#
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# When eager loaded, conditions are interpolated in the context of the model class, not the model instance. Conditions are lazily interpolated
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# before the actual model exists.
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#
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# == Table Aliasing
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#
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# ActiveRecord uses table aliasing in the case that a table is referenced multiple times in a join. If a table is referenced only once,
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# the standard table name is used. The second time, the table is aliased as #{reflection_name}_#{parent_table_name}. Indexes are appended
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# for any more successive uses of the table name.
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#
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# Post.find :all, :include => :comments
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# # => SELECT ... FROM posts LEFT OUTER JOIN comments ON ...
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# Post.find :all, :include => :special_comments # STI
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# # => SELECT ... FROM posts LEFT OUTER JOIN comments ON ... AND comments.type = 'SpecialComment'
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# Post.find :all, :include => [:comments, :special_comments] # special_comments is the reflection name, posts is the parent table name
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# # => SELECT ... FROM posts LEFT OUTER JOIN comments ON ... LEFT OUTER JOIN comments special_comments_posts
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#
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# Acts as tree example:
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#
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# TreeMixin.find :all, :include => :children
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# # => SELECT ... FROM mixins LEFT OUTER JOIN mixins childrens_mixins ...
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# TreeMixin.find :all, :include => {:children => :parent} # using cascading eager includes
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# # => SELECT ... FROM mixins LEFT OUTER JOIN mixins childrens_mixins ...
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# LEFT OUTER JOIN parents_mixins ...
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# TreeMixin.find :all, :include => {:children => {:parent => :children}}
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# # => SELECT ... FROM mixins LEFT OUTER JOIN mixins childrens_mixins ...
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# LEFT OUTER JOIN parents_mixins ...
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# LEFT OUTER JOIN mixins childrens_mixins_2
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#
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# Has and Belongs to Many join tables use the same idea, but add a _join suffix:
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#
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# Post.find :all, :include => :categories
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# # => SELECT ... FROM posts LEFT OUTER JOIN categories_posts ... LEFT OUTER JOIN categories ...
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# Post.find :all, :include => {:categories => :posts}
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# # => SELECT ... FROM posts LEFT OUTER JOIN categories_posts ... LEFT OUTER JOIN categories ...
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# LEFT OUTER JOIN categories_posts posts_categories_join LEFT OUTER JOIN posts posts_categories
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# Post.find :all, :include => {:categories => {:posts => :categories}}
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# # => SELECT ... FROM posts LEFT OUTER JOIN categories_posts ... LEFT OUTER JOIN categories ...
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# LEFT OUTER JOIN categories_posts posts_categories_join LEFT OUTER JOIN posts posts_categories
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# LEFT OUTER JOIN categories_posts categories_posts_join LEFT OUTER JOIN categories categories_posts
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#
|
|
# If you wish to specify your own custom joins using a :joins option, those table names will take precedence over the eager associations..
|
|
#
|
|
# Post.find :all, :include => :comments, :joins => "inner join comments ..."
|
|
# # => SELECT ... FROM posts LEFT OUTER JOIN comments_posts ON ... INNER JOIN comments ...
|
|
# Post.find :all, :include => [:comments, :special_comments], :joins => "inner join comments ..."
|
|
# # => SELECT ... FROM posts LEFT OUTER JOIN comments comments_posts ON ...
|
|
# LEFT OUTER JOIN comments special_comments_posts ...
|
|
# INNER JOIN comments ...
|
|
#
|
|
# Table aliases are automatically truncated according to the maximum length of table identifiers according to the specific database.
|
|
#
|
|
# == Modules
|
|
#
|
|
# By default, associations will look for objects within the current module scope. Consider:
|
|
#
|
|
# module MyApplication
|
|
# module Business
|
|
# class Firm < ActiveRecord::Base
|
|
# has_many :clients
|
|
# end
|
|
#
|
|
# class Company < ActiveRecord::Base; end
|
|
# end
|
|
# end
|
|
#
|
|
# When Firm#clients is called, it'll in turn call <tt>MyApplication::Business::Company.find(firm.id)</tt>. If you want to associate
|
|
# with a class in another module scope this can be done by specifying the complete class name, such as:
|
|
#
|
|
# module MyApplication
|
|
# module Business
|
|
# class Firm < ActiveRecord::Base; end
|
|
# end
|
|
#
|
|
# module Billing
|
|
# class Account < ActiveRecord::Base
|
|
# belongs_to :firm, :class_name => "MyApplication::Business::Firm"
|
|
# end
|
|
# end
|
|
# end
|
|
#
|
|
# == Type safety with ActiveRecord::AssociationTypeMismatch
|
|
#
|
|
# If you attempt to assign an object to an association that doesn't match the inferred or specified <tt>:class_name</tt>, you'll
|
|
# get a ActiveRecord::AssociationTypeMismatch.
|
|
#
|
|
# == Options
|
|
#
|
|
# All of the association macros can be specialized through options which makes more complex cases than the simple and guessable ones
|
|
# possible.
|
|
module ClassMethods
|
|
# Adds the following methods for retrieval and query of collections of associated objects.
|
|
# +collection+ is replaced with the symbol passed as the first argument, so
|
|
# <tt>has_many :clients</tt> would add among others <tt>clients.empty?</tt>.
|
|
# * <tt>collection(force_reload = false)</tt> - returns an array of all the associated objects.
|
|
# An empty array is returned if none are found.
|
|
# * <tt>collection<<(object, ...)</tt> - adds one or more objects to the collection by setting their foreign keys to the collection's primary key.
|
|
# * <tt>collection.delete(object, ...)</tt> - removes one or more objects from the collection by setting their foreign keys to NULL.
|
|
# This will also destroy the objects if they're declared as belongs_to and dependent on this model.
|
|
# * <tt>collection=objects</tt> - replaces the collections content by deleting and adding objects as appropriate.
|
|
# * <tt>collection_singular_ids</tt> - returns an array of the associated objects ids
|
|
# * <tt>collection_singular_ids=ids</tt> - replace the collection by the objects identified by the primary keys in +ids+
|
|
# * <tt>collection.clear</tt> - removes every object from the collection. This destroys the associated objects if they
|
|
# are <tt>:dependent</tt>, deletes them directly from the database if they are <tt>:dependent => :delete_all</tt>,
|
|
# and sets their foreign keys to NULL otherwise.
|
|
# * <tt>collection.empty?</tt> - returns true if there are no associated objects.
|
|
# * <tt>collection.size</tt> - returns the number of associated objects.
|
|
# * <tt>collection.find</tt> - finds an associated object according to the same rules as Base.find.
|
|
# * <tt>collection.build(attributes = {})</tt> - returns a new object of the collection type that has been instantiated
|
|
# with +attributes+ and linked to this object through a foreign key but has not yet been saved. *Note:* This only works if an
|
|
# associated object already exists, not if it's nil!
|
|
# * <tt>collection.create(attributes = {})</tt> - returns a new object of the collection type that has been instantiated
|
|
# with +attributes+ and linked to this object through a foreign key and that has already been saved (if it passed the validation).
|
|
# *Note:* This only works if an associated object already exists, not if it's nil!
|
|
#
|
|
# Example: A Firm class declares <tt>has_many :clients</tt>, which will add:
|
|
# * <tt>Firm#clients</tt> (similar to <tt>Clients.find :all, :conditions => "firm_id = #{id}"</tt>)
|
|
# * <tt>Firm#clients<<</tt>
|
|
# * <tt>Firm#clients.delete</tt>
|
|
# * <tt>Firm#clients=</tt>
|
|
# * <tt>Firm#client_ids</tt>
|
|
# * <tt>Firm#client_ids=</tt>
|
|
# * <tt>Firm#clients.clear</tt>
|
|
# * <tt>Firm#clients.empty?</tt> (similar to <tt>firm.clients.size == 0</tt>)
|
|
# * <tt>Firm#clients.size</tt> (similar to <tt>Client.count "firm_id = #{id}"</tt>)
|
|
# * <tt>Firm#clients.find</tt> (similar to <tt>Client.find(id, :conditions => "firm_id = #{id}")</tt>)
|
|
# * <tt>Firm#clients.build</tt> (similar to <tt>Client.new("firm_id" => id)</tt>)
|
|
# * <tt>Firm#clients.create</tt> (similar to <tt>c = Client.new("firm_id" => id); c.save; c</tt>)
|
|
# The declaration can also include an options hash to specialize the behavior of the association.
|
|
#
|
|
# Options are:
|
|
# * <tt>:class_name</tt> - specify the class name of the association. Use it only if that name can't be inferred
|
|
# from the association name. So <tt>has_many :products</tt> will by default be linked to the +Product+ class, but
|
|
# if the real class name is +SpecialProduct+, you'll have to specify it with this option.
|
|
# * <tt>:conditions</tt> - specify the conditions that the associated objects must meet in order to be included as a "WHERE"
|
|
# sql fragment, such as "price > 5 AND name LIKE 'B%'".
|
|
# * <tt>:order</tt> - specify the order in which the associated objects are returned as a "ORDER BY" sql fragment,
|
|
# such as "last_name, first_name DESC"
|
|
# * <tt>:group</tt> - specify the attribute by which the associated objects are returned as a "GROUP BY" sql fragment,
|
|
# such as "category"
|
|
# * <tt>:foreign_key</tt> - specify the foreign key used for the association. By default this is guessed to be the name
|
|
# of this class in lower-case and "_id" suffixed. So a +Person+ class that makes a has_many association will use "person_id"
|
|
# as the default foreign_key.
|
|
# * <tt>:dependent</tt> - if set to :destroy all the associated objects are destroyed
|
|
# alongside this object by calling their destroy method. If set to :delete_all all associated
|
|
# objects are deleted *without* calling their destroy method. If set to :nullify all associated
|
|
# objects' foreign keys are set to NULL *without* calling their save callbacks.
|
|
# NOTE: :dependent => true is deprecated and has been replaced with :dependent => :destroy.
|
|
# May not be set if :exclusively_dependent is also set.
|
|
# * <tt>:exclusively_dependent</tt> - Deprecated; equivalent to :dependent => :delete_all. If set to true all
|
|
# the associated object are deleted in one SQL statement without having their
|
|
# before_destroy callback run. This should only be used on associations that depend solely on this class and don't need to do any
|
|
# clean-up in before_destroy. The upside is that it's much faster, especially if there's a counter_cache involved.
|
|
# May not be set if :dependent is also set.
|
|
# * <tt>:finder_sql</tt> - specify a complete SQL statement to fetch the association. This is a good way to go for complex
|
|
# associations that depend on multiple tables. Note: When this option is used, +find_in_collection+ is _not_ added.
|
|
# * <tt>:counter_sql</tt> - specify a complete SQL statement to fetch the size of the association. If +:finder_sql+ is
|
|
# specified but +:counter_sql+, +:counter_sql+ will be generated by replacing SELECT ... FROM with SELECT COUNT(*) FROM.
|
|
# * <tt>:extend</tt> - specify a named module for extending the proxy, see "Association extensions".
|
|
# * <tt>:include</tt> - specify second-order associations that should be eager loaded when the collection is loaded.
|
|
# * <tt>:group</tt>: An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause.
|
|
# * <tt>:limit</tt>: An integer determining the limit on the number of rows that should be returned.
|
|
# * <tt>:offset</tt>: An integer determining the offset from where the rows should be fetched. So at 5, it would skip the first 4 rows.
|
|
# * <tt>:select</tt>: By default, this is * as in SELECT * FROM, but can be changed if you for example want to do a join, but not
|
|
# include the joined columns.
|
|
# * <tt>:as</tt>: Specifies a polymorphic interface (See #belongs_to).
|
|
# * <tt>:through</tt>: Specifies a Join Model to perform the query through. Options for <tt>:class_name</tt> and <tt>:foreign_key</tt>
|
|
# are ignored, as the association uses the source reflection. You can only use a <tt>:through</tt> query through a <tt>belongs_to</tt>
|
|
# or <tt>has_many</tt> association.
|
|
# * <tt>:source</tt>: Specifies the source association name used by <tt>has_many :through</tt> queries. Only use it if the name cannot be
|
|
# inferred from the association. <tt>has_many :subscribers, :through => :subscriptions</tt> will look for either +:subscribers+ or
|
|
# +:subscriber+ on +Subscription+, unless a +:source+ is given.
|
|
# * <tt>:source_type</tt>: Specifies type of the source association used by <tt>has_many :through</tt> queries where the source association
|
|
# is a polymorphic belongs_to.
|
|
# * <tt>:uniq</tt> - if set to true, duplicates will be omitted from the collection. Useful in conjunction with :through.
|
|
#
|
|
# Option examples:
|
|
# has_many :comments, :order => "posted_on"
|
|
# has_many :comments, :include => :author
|
|
# has_many :people, :class_name => "Person", :conditions => "deleted = 0", :order => "name"
|
|
# has_many :tracks, :order => "position", :dependent => :destroy
|
|
# has_many :comments, :dependent => :nullify
|
|
# has_many :tags, :as => :taggable
|
|
# has_many :subscribers, :through => :subscriptions, :source => :user
|
|
# has_many :subscribers, :class_name => "Person", :finder_sql =>
|
|
# 'SELECT DISTINCT people.* ' +
|
|
# 'FROM people p, post_subscriptions ps ' +
|
|
# 'WHERE ps.post_id = #{id} AND ps.person_id = p.id ' +
|
|
# 'ORDER BY p.first_name'
|
|
def has_many(association_id, options = {}, &extension)
|
|
reflection = create_has_many_reflection(association_id, options, &extension)
|
|
|
|
configure_dependency_for_has_many(reflection)
|
|
|
|
if options[:through]
|
|
collection_reader_method(reflection, HasManyThroughAssociation)
|
|
else
|
|
add_multiple_associated_save_callbacks(reflection.name)
|
|
add_association_callbacks(reflection.name, reflection.options)
|
|
collection_accessor_methods(reflection, HasManyAssociation)
|
|
end
|
|
|
|
add_deprecated_api_for_has_many(reflection.name)
|
|
end
|
|
|
|
# Adds the following methods for retrieval and query of a single associated object.
|
|
# +association+ is replaced with the symbol passed as the first argument, so
|
|
# <tt>has_one :manager</tt> would add among others <tt>manager.nil?</tt>.
|
|
# * <tt>association(force_reload = false)</tt> - returns the associated object. Nil is returned if none is found.
|
|
# * <tt>association=(associate)</tt> - assigns the associate object, extracts the primary key, sets it as the foreign key,
|
|
# and saves the associate object.
|
|
# * <tt>association.nil?</tt> - returns true if there is no associated object.
|
|
# * <tt>build_association(attributes = {})</tt> - returns a new object of the associated type that has been instantiated
|
|
# with +attributes+ and linked to this object through a foreign key but has not yet been saved. Note: This ONLY works if
|
|
# an association already exists. It will NOT work if the association is nil.
|
|
# * <tt>create_association(attributes = {})</tt> - returns a new object of the associated type that has been instantiated
|
|
# with +attributes+ and linked to this object through a foreign key and that has already been saved (if it passed the validation).
|
|
#
|
|
# Example: An Account class declares <tt>has_one :beneficiary</tt>, which will add:
|
|
# * <tt>Account#beneficiary</tt> (similar to <tt>Beneficiary.find(:first, :conditions => "account_id = #{id}")</tt>)
|
|
# * <tt>Account#beneficiary=(beneficiary)</tt> (similar to <tt>beneficiary.account_id = account.id; beneficiary.save</tt>)
|
|
# * <tt>Account#beneficiary.nil?</tt>
|
|
# * <tt>Account#build_beneficiary</tt> (similar to <tt>Beneficiary.new("account_id" => id)</tt>)
|
|
# * <tt>Account#create_beneficiary</tt> (similar to <tt>b = Beneficiary.new("account_id" => id); b.save; b</tt>)
|
|
#
|
|
# The declaration can also include an options hash to specialize the behavior of the association.
|
|
#
|
|
# Options are:
|
|
# * <tt>:class_name</tt> - specify the class name of the association. Use it only if that name can't be inferred
|
|
# from the association name. So <tt>has_one :manager</tt> will by default be linked to the +Manager+ class, but
|
|
# if the real class name is +Person+, you'll have to specify it with this option.
|
|
# * <tt>:conditions</tt> - specify the conditions that the associated object must meet in order to be included as a "WHERE"
|
|
# sql fragment, such as "rank = 5".
|
|
# * <tt>:order</tt> - specify the order from which the associated object will be picked at the top. Specified as
|
|
# an "ORDER BY" sql fragment, such as "last_name, first_name DESC"
|
|
# * <tt>:dependent</tt> - if set to :destroy (or true) the associated object is destroyed when this object is. If set to
|
|
# :delete the associated object is deleted *without* calling its destroy method. If set to :nullify the associated
|
|
# object's foreign key is set to NULL. Also, association is assigned.
|
|
# * <tt>:foreign_key</tt> - specify the foreign key used for the association. By default this is guessed to be the name
|
|
# of this class in lower-case and "_id" suffixed. So a +Person+ class that makes a has_one association will use "person_id"
|
|
# as the default foreign_key.
|
|
# * <tt>:include</tt> - specify second-order associations that should be eager loaded when this object is loaded.
|
|
# * <tt>:as</tt>: Specifies a polymorphic interface (See #belongs_to).
|
|
#
|
|
# Option examples:
|
|
# has_one :credit_card, :dependent => :destroy # destroys the associated credit card
|
|
# has_one :credit_card, :dependent => :nullify # updates the associated records foriegn key value to null rather than destroying it
|
|
# has_one :last_comment, :class_name => "Comment", :order => "posted_on"
|
|
# has_one :project_manager, :class_name => "Person", :conditions => "role = 'project_manager'"
|
|
# has_one :attachment, :as => :attachable
|
|
def has_one(association_id, options = {})
|
|
reflection = create_has_one_reflection(association_id, options)
|
|
|
|
module_eval do
|
|
after_save <<-EOF
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
if !association.nil? && (new_record? || association.new_record? || association["#{reflection.primary_key_name}"] != id)
|
|
association["#{reflection.primary_key_name}"] = id
|
|
association.save(true)
|
|
end
|
|
EOF
|
|
end
|
|
|
|
association_accessor_methods(reflection, HasOneAssociation)
|
|
association_constructor_method(:build, reflection, HasOneAssociation)
|
|
association_constructor_method(:create, reflection, HasOneAssociation)
|
|
|
|
configure_dependency_for_has_one(reflection)
|
|
|
|
# deprecated api
|
|
deprecated_has_association_method(reflection.name)
|
|
deprecated_association_comparison_method(reflection.name, reflection.class_name)
|
|
end
|
|
|
|
# Adds the following methods for retrieval and query for a single associated object that this object holds an id to.
|
|
# +association+ is replaced with the symbol passed as the first argument, so
|
|
# <tt>belongs_to :author</tt> would add among others <tt>author.nil?</tt>.
|
|
# * <tt>association(force_reload = false)</tt> - returns the associated object. Nil is returned if none is found.
|
|
# * <tt>association=(associate)</tt> - assigns the associate object, extracts the primary key, and sets it as the foreign key.
|
|
# * <tt>association.nil?</tt> - returns true if there is no associated object.
|
|
# * <tt>build_association(attributes = {})</tt> - returns a new object of the associated type that has been instantiated
|
|
# with +attributes+ and linked to this object through a foreign key but has not yet been saved.
|
|
# * <tt>create_association(attributes = {})</tt> - returns a new object of the associated type that has been instantiated
|
|
# with +attributes+ and linked to this object through a foreign key and that has already been saved (if it passed the validation).
|
|
#
|
|
# Example: A Post class declares <tt>belongs_to :author</tt>, which will add:
|
|
# * <tt>Post#author</tt> (similar to <tt>Author.find(author_id)</tt>)
|
|
# * <tt>Post#author=(author)</tt> (similar to <tt>post.author_id = author.id</tt>)
|
|
# * <tt>Post#author?</tt> (similar to <tt>post.author == some_author</tt>)
|
|
# * <tt>Post#author.nil?</tt>
|
|
# * <tt>Post#build_author</tt> (similar to <tt>post.author = Author.new</tt>)
|
|
# * <tt>Post#create_author</tt> (similar to <tt>post.author = Author.new; post.author.save; post.author</tt>)
|
|
# The declaration can also include an options hash to specialize the behavior of the association.
|
|
#
|
|
# Options are:
|
|
# * <tt>:class_name</tt> - specify the class name of the association. Use it only if that name can't be inferred
|
|
# from the association name. So <tt>has_one :author</tt> will by default be linked to the +Author+ class, but
|
|
# if the real class name is +Person+, you'll have to specify it with this option.
|
|
# * <tt>:conditions</tt> - specify the conditions that the associated object must meet in order to be included as a "WHERE"
|
|
# sql fragment, such as "authorized = 1".
|
|
# * <tt>:order</tt> - specify the order from which the associated object will be picked at the top. Specified as
|
|
# an "ORDER BY" sql fragment, such as "last_name, first_name DESC"
|
|
# * <tt>:foreign_key</tt> - specify the foreign key used for the association. By default this is guessed to be the name
|
|
# of the associated class in lower-case and "_id" suffixed. So a +Person+ class that makes a belongs_to association to a
|
|
# +Boss+ class will use "boss_id" as the default foreign_key.
|
|
# * <tt>:counter_cache</tt> - caches the number of belonging objects on the associate class through use of increment_counter
|
|
# and decrement_counter. The counter cache is incremented when an object of this class is created and decremented when it's
|
|
# destroyed. This requires that a column named "#{table_name}_count" (such as comments_count for a belonging Comment class)
|
|
# is used on the associate class (such as a Post class). You can also specify a custom counter cache column by given that
|
|
# name instead of a true/false value to this option (e.g., <tt>:counter_cache => :my_custom_counter</tt>.)
|
|
# * <tt>:include</tt> - specify second-order associations that should be eager loaded when this object is loaded.
|
|
# * <tt>:polymorphic</tt> - specify this association is a polymorphic association by passing true.
|
|
#
|
|
# Option examples:
|
|
# belongs_to :firm, :foreign_key => "client_of"
|
|
# belongs_to :author, :class_name => "Person", :foreign_key => "author_id"
|
|
# belongs_to :valid_coupon, :class_name => "Coupon", :foreign_key => "coupon_id",
|
|
# :conditions => 'discounts > #{payments_count}'
|
|
# belongs_to :attachable, :polymorphic => true
|
|
def belongs_to(association_id, options = {})
|
|
if options.include?(:class_name) && !options.include?(:foreign_key)
|
|
::ActiveSupport::Deprecation.warn(
|
|
"The inferred foreign_key name will change in Rails 2.0 to use the association name instead of its class name when they differ. When using :class_name in belongs_to, use the :foreign_key option to explicitly set the key name to avoid problems in the transition.",
|
|
caller)
|
|
end
|
|
|
|
reflection = create_belongs_to_reflection(association_id, options)
|
|
|
|
if reflection.options[:polymorphic]
|
|
association_accessor_methods(reflection, BelongsToPolymorphicAssociation)
|
|
|
|
module_eval do
|
|
before_save <<-EOF
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
if association && association.target
|
|
if association.new_record?
|
|
association.save(true)
|
|
end
|
|
|
|
if association.updated?
|
|
self["#{reflection.primary_key_name}"] = association.id
|
|
self["#{reflection.options[:foreign_type]}"] = association.class.base_class.name.to_s
|
|
end
|
|
end
|
|
EOF
|
|
end
|
|
else
|
|
association_accessor_methods(reflection, BelongsToAssociation)
|
|
association_constructor_method(:build, reflection, BelongsToAssociation)
|
|
association_constructor_method(:create, reflection, BelongsToAssociation)
|
|
|
|
module_eval do
|
|
before_save <<-EOF
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
if !association.nil?
|
|
if association.new_record?
|
|
association.save(true)
|
|
end
|
|
|
|
if association.updated?
|
|
self["#{reflection.primary_key_name}"] = association.id
|
|
end
|
|
end
|
|
EOF
|
|
end
|
|
|
|
# deprecated api
|
|
deprecated_has_association_method(reflection.name)
|
|
deprecated_association_comparison_method(reflection.name, reflection.class_name)
|
|
end
|
|
|
|
# Create the callbacks to update counter cache
|
|
if options[:counter_cache]
|
|
cache_column = options[:counter_cache] == true ?
|
|
"#{self.to_s.underscore.pluralize}_count" :
|
|
options[:counter_cache]
|
|
|
|
module_eval(
|
|
"after_create '#{reflection.name}.class.increment_counter(\"#{cache_column}\", #{reflection.primary_key_name})" +
|
|
" unless #{reflection.name}.nil?'"
|
|
)
|
|
|
|
module_eval(
|
|
"before_destroy '#{reflection.name}.class.decrement_counter(\"#{cache_column}\", #{reflection.primary_key_name})" +
|
|
" unless #{reflection.name}.nil?'"
|
|
)
|
|
end
|
|
end
|
|
|
|
# Associates two classes via an intermediate join table. Unless the join table is explicitly specified as
|
|
# an option, it is guessed using the lexical order of the class names. So a join between Developer and Project
|
|
# will give the default join table name of "developers_projects" because "D" outranks "P". Note that this precedence
|
|
# is calculated using the <tt><</tt> operator for <tt>String</tt>. This means that if the strings are of different lengths,
|
|
# and the strings are equal when compared up to the shortest length, then the longer string is considered of higher
|
|
# lexical precedence than the shorter one. For example, one would expect the tables <tt>paper_boxes</tt> and <tt>papers</tt>
|
|
# to generate a join table name of <tt>papers_paper_boxes</tt> because of the length of the name <tt>paper_boxes</tt>,
|
|
# but it in fact generates a join table name of <tt>paper_boxes_papers</tt>. Be aware of this caveat, and use the
|
|
# custom <tt>join_table</tt> option if you need to.
|
|
#
|
|
# Deprecated: Any additional fields added to the join table will be placed as attributes when pulling records out through
|
|
# has_and_belongs_to_many associations. Records returned from join tables with additional attributes will be marked as
|
|
# ReadOnly (because we can't save changes to the additional attrbutes). It's strongly recommended that you upgrade any
|
|
# associations with attributes to a real join model (see introduction).
|
|
#
|
|
# Adds the following methods for retrieval and query.
|
|
# +collection+ is replaced with the symbol passed as the first argument, so
|
|
# <tt>has_and_belongs_to_many :categories</tt> would add among others <tt>categories.empty?</tt>.
|
|
# * <tt>collection(force_reload = false)</tt> - returns an array of all the associated objects.
|
|
# An empty array is returned if none is found.
|
|
# * <tt>collection<<(object, ...)</tt> - adds one or more objects to the collection by creating associations in the join table
|
|
# (collection.push and collection.concat are aliases to this method).
|
|
# * <tt>collection.push_with_attributes(object, join_attributes)</tt> - adds one to the collection by creating an association in the join table that
|
|
# also holds the attributes from <tt>join_attributes</tt> (should be a hash with the column names as keys). This can be used to have additional
|
|
# attributes on the join, which will be injected into the associated objects when they are retrieved through the collection.
|
|
# (collection.concat_with_attributes is an alias to this method). This method is now deprecated.
|
|
# * <tt>collection.delete(object, ...)</tt> - removes one or more objects from the collection by removing their associations from the join table.
|
|
# This does not destroy the objects.
|
|
# * <tt>collection=objects</tt> - replaces the collections content by deleting and adding objects as appropriate.
|
|
# * <tt>collection_singular_ids</tt> - returns an array of the associated objects ids
|
|
# * <tt>collection_singular_ids=ids</tt> - replace the collection by the objects identified by the primary keys in +ids+
|
|
# * <tt>collection.clear</tt> - removes every object from the collection. This does not destroy the objects.
|
|
# * <tt>collection.empty?</tt> - returns true if there are no associated objects.
|
|
# * <tt>collection.size</tt> - returns the number of associated objects.
|
|
# * <tt>collection.find(id)</tt> - finds an associated object responding to the +id+ and that
|
|
# meets the condition that it has to be associated with this object.
|
|
# * <tt>collection.build(attributes = {})</tt> - returns a new object of the collection type that has been instantiated
|
|
# with +attributes+ and linked to this object through the join table but has not yet been saved.
|
|
# * <tt>collection.create(attributes = {})</tt> - returns a new object of the collection type that has been instantiated
|
|
# with +attributes+ and linked to this object through the join table and that has already been saved (if it passed the validation).
|
|
#
|
|
# Example: An Developer class declares <tt>has_and_belongs_to_many :projects</tt>, which will add:
|
|
# * <tt>Developer#projects</tt>
|
|
# * <tt>Developer#projects<<</tt>
|
|
# * <tt>Developer#projects.delete</tt>
|
|
# * <tt>Developer#projects=</tt>
|
|
# * <tt>Developer#project_ids</tt>
|
|
# * <tt>Developer#project_ids=</tt>
|
|
# * <tt>Developer#projects.clear</tt>
|
|
# * <tt>Developer#projects.empty?</tt>
|
|
# * <tt>Developer#projects.size</tt>
|
|
# * <tt>Developer#projects.find(id)</tt>
|
|
# * <tt>Developer#projects.build</tt> (similar to <tt>Project.new("project_id" => id)</tt>)
|
|
# * <tt>Developer#projects.create</tt> (similar to <tt>c = Project.new("project_id" => id); c.save; c</tt>)
|
|
# The declaration may include an options hash to specialize the behavior of the association.
|
|
#
|
|
# Options are:
|
|
# * <tt>:class_name</tt> - specify the class name of the association. Use it only if that name can't be inferred
|
|
# from the association name. So <tt>has_and_belongs_to_many :projects</tt> will by default be linked to the
|
|
# +Project+ class, but if the real class name is +SuperProject+, you'll have to specify it with this option.
|
|
# * <tt>:join_table</tt> - specify the name of the join table if the default based on lexical order isn't what you want.
|
|
# WARNING: If you're overwriting the table name of either class, the table_name method MUST be declared underneath any
|
|
# has_and_belongs_to_many declaration in order to work.
|
|
# * <tt>:foreign_key</tt> - specify the foreign key used for the association. By default this is guessed to be the name
|
|
# of this class in lower-case and "_id" suffixed. So a +Person+ class that makes a has_and_belongs_to_many association
|
|
# will use "person_id" as the default foreign_key.
|
|
# * <tt>:association_foreign_key</tt> - specify the association foreign key used for the association. By default this is
|
|
# guessed to be the name of the associated class in lower-case and "_id" suffixed. So if the associated class is +Project+,
|
|
# the has_and_belongs_to_many association will use "project_id" as the default association foreign_key.
|
|
# * <tt>:conditions</tt> - specify the conditions that the associated object must meet in order to be included as a "WHERE"
|
|
# sql fragment, such as "authorized = 1".
|
|
# * <tt>:order</tt> - specify the order in which the associated objects are returned as a "ORDER BY" sql fragment, such as "last_name, first_name DESC"
|
|
# * <tt>:uniq</tt> - if set to true, duplicate associated objects will be ignored by accessors and query methods
|
|
# * <tt>:finder_sql</tt> - overwrite the default generated SQL used to fetch the association with a manual one
|
|
# * <tt>:delete_sql</tt> - overwrite the default generated SQL used to remove links between the associated
|
|
# classes with a manual one
|
|
# * <tt>:insert_sql</tt> - overwrite the default generated SQL used to add links between the associated classes
|
|
# with a manual one
|
|
# * <tt>:extend</tt> - anonymous module for extending the proxy, see "Association extensions".
|
|
# * <tt>:include</tt> - specify second-order associations that should be eager loaded when the collection is loaded.
|
|
# * <tt>:group</tt>: An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause.
|
|
# * <tt>:limit</tt>: An integer determining the limit on the number of rows that should be returned.
|
|
# * <tt>:offset</tt>: An integer determining the offset from where the rows should be fetched. So at 5, it would skip the first 4 rows.
|
|
# * <tt>:select</tt>: By default, this is * as in SELECT * FROM, but can be changed if you for example want to do a join, but not
|
|
# include the joined columns.
|
|
#
|
|
# Option examples:
|
|
# has_and_belongs_to_many :projects
|
|
# has_and_belongs_to_many :projects, :include => [ :milestones, :manager ]
|
|
# has_and_belongs_to_many :nations, :class_name => "Country"
|
|
# has_and_belongs_to_many :categories, :join_table => "prods_cats"
|
|
# has_and_belongs_to_many :active_projects, :join_table => 'developers_projects', :delete_sql =>
|
|
# 'DELETE FROM developers_projects WHERE active=1 AND developer_id = #{id} AND project_id = #{record.id}'
|
|
def has_and_belongs_to_many(association_id, options = {}, &extension)
|
|
reflection = create_has_and_belongs_to_many_reflection(association_id, options, &extension)
|
|
|
|
add_multiple_associated_save_callbacks(reflection.name)
|
|
collection_accessor_methods(reflection, HasAndBelongsToManyAssociation)
|
|
|
|
# Don't use a before_destroy callback since users' before_destroy
|
|
# callbacks will be executed after the association is wiped out.
|
|
old_method = "destroy_without_habtm_shim_for_#{reflection.name}"
|
|
class_eval <<-end_eval
|
|
alias_method :#{old_method}, :destroy_without_callbacks
|
|
def destroy_without_callbacks
|
|
#{reflection.name}.clear
|
|
#{old_method}
|
|
end
|
|
end_eval
|
|
|
|
add_association_callbacks(reflection.name, options)
|
|
|
|
# deprecated api
|
|
deprecated_collection_count_method(reflection.name)
|
|
deprecated_add_association_relation(reflection.name)
|
|
deprecated_remove_association_relation(reflection.name)
|
|
deprecated_has_collection_method(reflection.name)
|
|
end
|
|
|
|
private
|
|
# Generate a join table name from two provided tables names.
|
|
# The order of names in join name is determined by lexical precedence.
|
|
# join_table_name("members", "clubs")
|
|
# => "clubs_members"
|
|
# join_table_name("members", "special_clubs")
|
|
# => "members_special_clubs"
|
|
def join_table_name(first_table_name, second_table_name)
|
|
if first_table_name < second_table_name
|
|
join_table = "#{first_table_name}_#{second_table_name}"
|
|
else
|
|
join_table = "#{second_table_name}_#{first_table_name}"
|
|
end
|
|
|
|
table_name_prefix + join_table + table_name_suffix
|
|
end
|
|
|
|
def association_accessor_methods(reflection, association_proxy_class)
|
|
define_method(reflection.name) do |*params|
|
|
force_reload = params.first unless params.empty?
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
|
|
if association.nil? || force_reload
|
|
association = association_proxy_class.new(self, reflection)
|
|
retval = association.reload
|
|
if retval.nil? and association_proxy_class == BelongsToAssociation
|
|
instance_variable_set("@#{reflection.name}", nil)
|
|
return nil
|
|
end
|
|
instance_variable_set("@#{reflection.name}", association)
|
|
end
|
|
|
|
association.target.nil? ? nil : association
|
|
end
|
|
|
|
define_method("#{reflection.name}=") do |new_value|
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
if association.nil? || association.target != new_value
|
|
association = association_proxy_class.new(self, reflection)
|
|
end
|
|
|
|
association.replace(new_value)
|
|
|
|
unless new_value.nil?
|
|
instance_variable_set("@#{reflection.name}", association)
|
|
else
|
|
instance_variable_set("@#{reflection.name}", nil)
|
|
end
|
|
end
|
|
|
|
define_method("set_#{reflection.name}_target") do |target|
|
|
return if target.nil? and association_proxy_class == BelongsToAssociation
|
|
association = association_proxy_class.new(self, reflection)
|
|
association.target = target
|
|
instance_variable_set("@#{reflection.name}", association)
|
|
end
|
|
end
|
|
|
|
def collection_reader_method(reflection, association_proxy_class)
|
|
define_method(reflection.name) do |*params|
|
|
force_reload = params.first unless params.empty?
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
|
|
unless association.respond_to?(:loaded?)
|
|
association = association_proxy_class.new(self, reflection)
|
|
instance_variable_set("@#{reflection.name}", association)
|
|
end
|
|
|
|
association.reload if force_reload
|
|
|
|
association
|
|
end
|
|
end
|
|
|
|
def collection_accessor_methods(reflection, association_proxy_class)
|
|
collection_reader_method(reflection, association_proxy_class)
|
|
|
|
define_method("#{reflection.name}=") do |new_value|
|
|
# Loads proxy class instance (defined in collection_reader_method) if not already loaded
|
|
association = send(reflection.name)
|
|
association.replace(new_value)
|
|
association
|
|
end
|
|
|
|
define_method("#{reflection.name.to_s.singularize}_ids") do
|
|
send(reflection.name).map(&:id)
|
|
end
|
|
|
|
define_method("#{reflection.name.to_s.singularize}_ids=") do |new_value|
|
|
ids = (new_value || []).reject { |nid| nid.blank? }
|
|
send("#{reflection.name}=", reflection.class_name.constantize.find(ids))
|
|
end
|
|
end
|
|
|
|
def add_multiple_associated_save_callbacks(association_name)
|
|
method_name = "validate_associated_records_for_#{association_name}".to_sym
|
|
define_method(method_name) do
|
|
association = instance_variable_get("@#{association_name}")
|
|
if association.respond_to?(:loaded?)
|
|
if new_record?
|
|
association
|
|
else
|
|
association.select { |record| record.new_record? }
|
|
end.each do |record|
|
|
errors.add "#{association_name}" unless record.valid?
|
|
end
|
|
end
|
|
end
|
|
|
|
validate method_name
|
|
before_save("@new_record_before_save = new_record?; true")
|
|
|
|
after_callback = <<-end_eval
|
|
association = instance_variable_get("@#{association_name}")
|
|
|
|
records_to_save = if @new_record_before_save
|
|
association
|
|
elsif association.respond_to?(:loaded?) && association.loaded?
|
|
association.select { |record| record.new_record? }
|
|
else
|
|
[]
|
|
end
|
|
|
|
if !records_to_save.blank?
|
|
records_to_save.each { |record| association.send(:insert_record, record) }
|
|
association.send(:construct_sql) # reconstruct the SQL queries now that we know the owner's id
|
|
end
|
|
end_eval
|
|
|
|
# Doesn't use after_save as that would save associations added in after_create/after_update twice
|
|
after_create(after_callback)
|
|
after_update(after_callback)
|
|
end
|
|
|
|
def association_constructor_method(constructor, reflection, association_proxy_class)
|
|
define_method("#{constructor}_#{reflection.name}") do |*params|
|
|
attributees = params.first unless params.empty?
|
|
replace_existing = params[1].nil? ? true : params[1]
|
|
association = instance_variable_get("@#{reflection.name}")
|
|
|
|
if association.nil?
|
|
association = association_proxy_class.new(self, reflection)
|
|
instance_variable_set("@#{reflection.name}", association)
|
|
end
|
|
|
|
if association_proxy_class == HasOneAssociation
|
|
association.send(constructor, attributees, replace_existing)
|
|
else
|
|
association.send(constructor, attributees)
|
|
end
|
|
end
|
|
end
|
|
|
|
def find_with_associations(options = {})
|
|
catch :invalid_query do
|
|
join_dependency = JoinDependency.new(self, merge_includes(scope(:find, :include), options[:include]), options[:joins])
|
|
rows = select_all_rows(options, join_dependency)
|
|
return join_dependency.instantiate(rows)
|
|
end
|
|
[]
|
|
end
|
|
|
|
def configure_dependency_for_has_many(reflection)
|
|
if reflection.options[:dependent] == true
|
|
::ActiveSupport::Deprecation.warn("The :dependent => true option is deprecated and will be removed from Rails 2.0. Please use :dependent => :destroy instead. See http://www.rubyonrails.org/deprecation for details.", caller)
|
|
end
|
|
|
|
if reflection.options[:dependent] && reflection.options[:exclusively_dependent]
|
|
raise ArgumentError, ':dependent and :exclusively_dependent are mutually exclusive options. You may specify one or the other.'
|
|
end
|
|
|
|
if reflection.options[:exclusively_dependent]
|
|
reflection.options[:dependent] = :delete_all
|
|
::ActiveSupport::Deprecation.warn("The :exclusively_dependent option is deprecated and will be removed from Rails 2.0. Please use :dependent => :delete_all instead. See http://www.rubyonrails.org/deprecation for details.", caller)
|
|
end
|
|
|
|
# See HasManyAssociation#delete_records. Dependent associations
|
|
# delete children, otherwise foreign key is set to NULL.
|
|
|
|
# Add polymorphic type if the :as option is present
|
|
dependent_conditions = %(#{reflection.primary_key_name} = \#{record.quoted_id})
|
|
if reflection.options[:as]
|
|
dependent_conditions += " AND #{reflection.options[:as]}_type = '#{base_class.name}'"
|
|
end
|
|
|
|
case reflection.options[:dependent]
|
|
when :destroy, true
|
|
module_eval "before_destroy '#{reflection.name}.each { |o| o.destroy }'"
|
|
when :delete_all
|
|
module_eval "before_destroy { |record| #{reflection.class_name}.delete_all(%(#{dependent_conditions})) }"
|
|
when :nullify
|
|
module_eval "before_destroy { |record| #{reflection.class_name}.update_all(%(#{reflection.primary_key_name} = NULL), %(#{dependent_conditions})) }"
|
|
when nil, false
|
|
# pass
|
|
else
|
|
raise ArgumentError, 'The :dependent option expects either :destroy, :delete_all, or :nullify'
|
|
end
|
|
end
|
|
|
|
def configure_dependency_for_has_one(reflection)
|
|
case reflection.options[:dependent]
|
|
when :destroy, true
|
|
module_eval "before_destroy '#{reflection.name}.destroy unless #{reflection.name}.nil?'"
|
|
when :delete
|
|
module_eval "before_destroy '#{reflection.class_name}.delete(#{reflection.name}.id) unless #{reflection.name}.nil?'"
|
|
when :nullify
|
|
module_eval "before_destroy '#{reflection.name}.update_attribute(\"#{reflection.primary_key_name}\", nil) unless #{reflection.name}.nil?'"
|
|
when nil, false
|
|
# pass
|
|
else
|
|
raise ArgumentError, "The :dependent option expects either :destroy, :delete or :nullify."
|
|
end
|
|
end
|
|
|
|
|
|
def add_deprecated_api_for_has_many(association_name)
|
|
deprecated_collection_count_method(association_name)
|
|
deprecated_add_association_relation(association_name)
|
|
deprecated_remove_association_relation(association_name)
|
|
deprecated_has_collection_method(association_name)
|
|
deprecated_find_in_collection_method(association_name)
|
|
deprecated_find_all_in_collection_method(association_name)
|
|
deprecated_collection_create_method(association_name)
|
|
deprecated_collection_build_method(association_name)
|
|
end
|
|
|
|
def create_has_many_reflection(association_id, options, &extension)
|
|
options.assert_valid_keys(
|
|
:class_name, :table_name, :foreign_key,
|
|
:exclusively_dependent, :dependent,
|
|
:select, :conditions, :include, :order, :group, :limit, :offset,
|
|
:as, :through, :source, :source_type,
|
|
:uniq,
|
|
:finder_sql, :counter_sql,
|
|
:before_add, :after_add, :before_remove, :after_remove,
|
|
:extend
|
|
)
|
|
|
|
options[:extend] = create_extension_module(association_id, extension) if block_given?
|
|
|
|
create_reflection(:has_many, association_id, options, self)
|
|
end
|
|
|
|
def create_has_one_reflection(association_id, options)
|
|
options.assert_valid_keys(
|
|
:class_name, :foreign_key, :remote, :conditions, :order, :include, :dependent, :counter_cache, :extend, :as
|
|
)
|
|
|
|
create_reflection(:has_one, association_id, options, self)
|
|
end
|
|
|
|
def create_belongs_to_reflection(association_id, options)
|
|
options.assert_valid_keys(
|
|
:class_name, :foreign_key, :foreign_type, :remote, :conditions, :order, :include, :dependent,
|
|
:counter_cache, :extend, :polymorphic
|
|
)
|
|
|
|
reflection = create_reflection(:belongs_to, association_id, options, self)
|
|
|
|
if options[:polymorphic]
|
|
reflection.options[:foreign_type] ||= reflection.class_name.underscore + "_type"
|
|
end
|
|
|
|
reflection
|
|
end
|
|
|
|
def create_has_and_belongs_to_many_reflection(association_id, options, &extension)
|
|
options.assert_valid_keys(
|
|
:class_name, :table_name, :join_table, :foreign_key, :association_foreign_key,
|
|
:select, :conditions, :include, :order, :group, :limit, :offset,
|
|
:uniq,
|
|
:finder_sql, :delete_sql, :insert_sql,
|
|
:before_add, :after_add, :before_remove, :after_remove,
|
|
:extend
|
|
)
|
|
|
|
options[:extend] = create_extension_module(association_id, extension) if block_given?
|
|
|
|
reflection = create_reflection(:has_and_belongs_to_many, association_id, options, self)
|
|
|
|
reflection.options[:join_table] ||= join_table_name(undecorated_table_name(self.to_s), undecorated_table_name(reflection.class_name))
|
|
|
|
reflection
|
|
end
|
|
|
|
def reflect_on_included_associations(associations)
|
|
[ associations ].flatten.collect { |association| reflect_on_association(association.to_s.intern) }
|
|
end
|
|
|
|
def guard_against_unlimitable_reflections(reflections, options)
|
|
if (options[:offset] || options[:limit]) && !using_limitable_reflections?(reflections)
|
|
raise(
|
|
ConfigurationError,
|
|
"You can not use offset and limit together with has_many or has_and_belongs_to_many associations"
|
|
)
|
|
end
|
|
end
|
|
|
|
def select_all_rows(options, join_dependency)
|
|
connection.select_all(
|
|
construct_finder_sql_with_included_associations(options, join_dependency),
|
|
"#{name} Load Including Associations"
|
|
)
|
|
end
|
|
|
|
def construct_finder_sql_with_included_associations(options, join_dependency)
|
|
scope = scope(:find)
|
|
sql = "SELECT #{column_aliases(join_dependency)} FROM #{(scope && scope[:from]) || options[:from] || table_name} "
|
|
sql << join_dependency.join_associations.collect{|join| join.association_join }.join
|
|
|
|
add_joins!(sql, options, scope)
|
|
add_conditions!(sql, options[:conditions], scope)
|
|
add_limited_ids_condition!(sql, options, join_dependency) if !using_limitable_reflections?(join_dependency.reflections) && ((scope && scope[:limit]) || options[:limit])
|
|
|
|
sql << "GROUP BY #{options[:group]} " if options[:group]
|
|
|
|
add_order!(sql, options[:order], scope)
|
|
add_limit!(sql, options, scope) if using_limitable_reflections?(join_dependency.reflections)
|
|
add_lock!(sql, options, scope)
|
|
|
|
return sanitize_sql(sql)
|
|
end
|
|
|
|
def add_limited_ids_condition!(sql, options, join_dependency)
|
|
unless (id_list = select_limited_ids_list(options, join_dependency)).empty?
|
|
sql << "#{condition_word(sql)} #{table_name}.#{primary_key} IN (#{id_list}) "
|
|
else
|
|
throw :invalid_query
|
|
end
|
|
end
|
|
|
|
def select_limited_ids_list(options, join_dependency)
|
|
connection.select_all(
|
|
construct_finder_sql_for_association_limiting(options, join_dependency),
|
|
"#{name} Load IDs For Limited Eager Loading"
|
|
).collect { |row| connection.quote(row[primary_key]) }.join(", ")
|
|
end
|
|
|
|
def construct_finder_sql_for_association_limiting(options, join_dependency)
|
|
scope = scope(:find)
|
|
is_distinct = include_eager_conditions?(options) || include_eager_order?(options)
|
|
sql = "SELECT "
|
|
if is_distinct
|
|
sql << connection.distinct("#{table_name}.#{primary_key}", options[:order])
|
|
else
|
|
sql << primary_key
|
|
end
|
|
sql << " FROM #{table_name} "
|
|
|
|
if is_distinct
|
|
sql << join_dependency.join_associations.collect(&:association_join).join
|
|
add_joins!(sql, options, scope)
|
|
end
|
|
|
|
add_conditions!(sql, options[:conditions], scope)
|
|
if options[:order]
|
|
if is_distinct
|
|
connection.add_order_by_for_association_limiting!(sql, options)
|
|
else
|
|
sql << "ORDER BY #{options[:order]}"
|
|
end
|
|
end
|
|
add_limit!(sql, options, scope)
|
|
return sanitize_sql(sql)
|
|
end
|
|
|
|
# Checks if the conditions reference a table other than the current model table
|
|
def include_eager_conditions?(options)
|
|
# look in both sets of conditions
|
|
conditions = [scope(:find, :conditions), options[:conditions]].inject([]) do |all, cond|
|
|
case cond
|
|
when nil then all
|
|
when Array then all << cond.first
|
|
else all << cond
|
|
end
|
|
end
|
|
return false unless conditions.any?
|
|
conditions.join(' ').scan(/([\.\w]+)\.\w+/).flatten.any? do |condition_table_name|
|
|
condition_table_name != table_name
|
|
end
|
|
end
|
|
|
|
# Checks if the query order references a table other than the current model's table.
|
|
def include_eager_order?(options)
|
|
order = options[:order]
|
|
return false unless order
|
|
order.scan(/([\.\w]+)\.\w+/).flatten.any? do |order_table_name|
|
|
order_table_name != table_name
|
|
end
|
|
end
|
|
|
|
def using_limitable_reflections?(reflections)
|
|
reflections.reject { |r| [ :belongs_to, :has_one ].include?(r.macro) }.length.zero?
|
|
end
|
|
|
|
def column_aliases(join_dependency)
|
|
join_dependency.joins.collect{|join| join.column_names_with_alias.collect{|column_name, aliased_name|
|
|
"#{join.aliased_table_name}.#{connection.quote_column_name column_name} AS #{aliased_name}"}}.flatten.join(", ")
|
|
end
|
|
|
|
def add_association_callbacks(association_name, options)
|
|
callbacks = %w(before_add after_add before_remove after_remove)
|
|
callbacks.each do |callback_name|
|
|
full_callback_name = "#{callback_name}_for_#{association_name}"
|
|
defined_callbacks = options[callback_name.to_sym]
|
|
if options.has_key?(callback_name.to_sym)
|
|
class_inheritable_reader full_callback_name.to_sym
|
|
write_inheritable_array(full_callback_name.to_sym, [defined_callbacks].flatten)
|
|
end
|
|
end
|
|
end
|
|
|
|
def condition_word(sql)
|
|
sql =~ /where/i ? " AND " : "WHERE "
|
|
end
|
|
|
|
def create_extension_module(association_id, extension)
|
|
extension_module_name = "#{self.to_s}#{association_id.to_s.camelize}AssociationExtension"
|
|
|
|
silence_warnings do
|
|
Object.const_set(extension_module_name, Module.new(&extension))
|
|
end
|
|
|
|
extension_module_name.constantize
|
|
end
|
|
|
|
class JoinDependency # :nodoc:
|
|
attr_reader :joins, :reflections, :table_aliases
|
|
|
|
def initialize(base, associations, joins)
|
|
@joins = [JoinBase.new(base, joins)]
|
|
@associations = associations
|
|
@reflections = []
|
|
@base_records_hash = {}
|
|
@base_records_in_order = []
|
|
@table_aliases = Hash.new { |aliases, table| aliases[table] = 0 }
|
|
@table_aliases[base.table_name] = 1
|
|
build(associations)
|
|
end
|
|
|
|
def join_associations
|
|
@joins[1..-1].to_a
|
|
end
|
|
|
|
def join_base
|
|
@joins[0]
|
|
end
|
|
|
|
def instantiate(rows)
|
|
rows.each_with_index do |row, i|
|
|
primary_id = join_base.record_id(row)
|
|
unless @base_records_hash[primary_id]
|
|
@base_records_in_order << (@base_records_hash[primary_id] = join_base.instantiate(row))
|
|
end
|
|
construct(@base_records_hash[primary_id], @associations, join_associations.dup, row)
|
|
end
|
|
return @base_records_in_order
|
|
end
|
|
|
|
def aliased_table_names_for(table_name)
|
|
joins.select{|join| join.table_name == table_name }.collect{|join| join.aliased_table_name}
|
|
end
|
|
|
|
protected
|
|
def build(associations, parent = nil)
|
|
parent ||= @joins.last
|
|
case associations
|
|
when Symbol, String
|
|
reflection = parent.reflections[associations.to_s.intern] or
|
|
raise ConfigurationError, "Association named '#{ associations }' was not found; perhaps you misspelled it?"
|
|
@reflections << reflection
|
|
@joins << JoinAssociation.new(reflection, self, parent)
|
|
when Array
|
|
associations.each do |association|
|
|
build(association, parent)
|
|
end
|
|
when Hash
|
|
associations.keys.sort{|a,b|a.to_s<=>b.to_s}.each do |name|
|
|
build(name, parent)
|
|
build(associations[name])
|
|
end
|
|
else
|
|
raise ConfigurationError, associations.inspect
|
|
end
|
|
end
|
|
|
|
def construct(parent, associations, joins, row)
|
|
case associations
|
|
when Symbol, String
|
|
while (join = joins.shift).reflection.name.to_s != associations.to_s
|
|
raise ConfigurationError, "Not Enough Associations" if joins.empty?
|
|
end
|
|
construct_association(parent, join, row)
|
|
when Array
|
|
associations.each do |association|
|
|
construct(parent, association, joins, row)
|
|
end
|
|
when Hash
|
|
associations.keys.sort{|a,b|a.to_s<=>b.to_s}.each do |name|
|
|
association = construct_association(parent, joins.shift, row)
|
|
construct(association, associations[name], joins, row) if association
|
|
end
|
|
else
|
|
raise ConfigurationError, associations.inspect
|
|
end
|
|
end
|
|
|
|
def construct_association(record, join, row)
|
|
case join.reflection.macro
|
|
when :has_many, :has_and_belongs_to_many
|
|
collection = record.send(join.reflection.name)
|
|
collection.loaded
|
|
|
|
return nil if record.id.to_s != join.parent.record_id(row).to_s or row[join.aliased_primary_key].nil?
|
|
association = join.instantiate(row)
|
|
collection.target.push(association) unless collection.target.include?(association)
|
|
when :has_one
|
|
return if record.id.to_s != join.parent.record_id(row).to_s
|
|
association = join.instantiate(row) unless row[join.aliased_primary_key].nil?
|
|
record.send("set_#{join.reflection.name}_target", association)
|
|
when :belongs_to
|
|
return if record.id.to_s != join.parent.record_id(row).to_s or row[join.aliased_primary_key].nil?
|
|
association = join.instantiate(row)
|
|
record.send("set_#{join.reflection.name}_target", association)
|
|
else
|
|
raise ConfigurationError, "unknown macro: #{join.reflection.macro}"
|
|
end
|
|
return association
|
|
end
|
|
|
|
class JoinBase # :nodoc:
|
|
attr_reader :active_record, :table_joins
|
|
delegate :table_name, :column_names, :primary_key, :reflections, :sanitize_sql, :to => :active_record
|
|
|
|
def initialize(active_record, joins = nil)
|
|
@active_record = active_record
|
|
@cached_record = {}
|
|
@table_joins = joins
|
|
end
|
|
|
|
def aliased_prefix
|
|
"t0"
|
|
end
|
|
|
|
def aliased_primary_key
|
|
"#{ aliased_prefix }_r0"
|
|
end
|
|
|
|
def aliased_table_name
|
|
active_record.table_name
|
|
end
|
|
|
|
def column_names_with_alias
|
|
unless @column_names_with_alias
|
|
@column_names_with_alias = []
|
|
([primary_key] + (column_names - [primary_key])).each_with_index do |column_name, i|
|
|
@column_names_with_alias << [column_name, "#{ aliased_prefix }_r#{ i }"]
|
|
end
|
|
end
|
|
return @column_names_with_alias
|
|
end
|
|
|
|
def extract_record(row)
|
|
column_names_with_alias.inject({}){|record, (cn, an)| record[cn] = row[an]; record}
|
|
end
|
|
|
|
def record_id(row)
|
|
row[aliased_primary_key]
|
|
end
|
|
|
|
def instantiate(row)
|
|
@cached_record[record_id(row)] ||= active_record.instantiate(extract_record(row))
|
|
end
|
|
end
|
|
|
|
class JoinAssociation < JoinBase # :nodoc:
|
|
attr_reader :reflection, :parent, :aliased_table_name, :aliased_prefix, :aliased_join_table_name, :parent_table_name
|
|
delegate :options, :klass, :through_reflection, :source_reflection, :to => :reflection
|
|
|
|
def initialize(reflection, join_dependency, parent = nil)
|
|
reflection.check_validity!
|
|
if reflection.options[:polymorphic]
|
|
raise EagerLoadPolymorphicError.new(reflection)
|
|
end
|
|
|
|
super(reflection.klass)
|
|
@parent = parent
|
|
@reflection = reflection
|
|
@aliased_prefix = "t#{ join_dependency.joins.size }"
|
|
@aliased_table_name = table_name #.tr('.', '_') # start with the table name, sub out any .'s
|
|
@parent_table_name = parent.active_record.table_name
|
|
|
|
if !parent.table_joins.blank? && parent.table_joins.to_s.downcase =~ %r{join(\s+\w+)?\s+#{aliased_table_name.downcase}\son}
|
|
join_dependency.table_aliases[aliased_table_name] += 1
|
|
end
|
|
|
|
unless join_dependency.table_aliases[aliased_table_name].zero?
|
|
# if the table name has been used, then use an alias
|
|
@aliased_table_name = active_record.connection.table_alias_for "#{pluralize(reflection.name)}_#{parent_table_name}"
|
|
table_index = join_dependency.table_aliases[aliased_table_name]
|
|
join_dependency.table_aliases[aliased_table_name] += 1
|
|
@aliased_table_name = @aliased_table_name[0..active_record.connection.table_alias_length-3] + "_#{table_index+1}" if table_index > 0
|
|
else
|
|
join_dependency.table_aliases[aliased_table_name] += 1
|
|
end
|
|
|
|
if reflection.macro == :has_and_belongs_to_many || (reflection.macro == :has_many && reflection.options[:through])
|
|
@aliased_join_table_name = reflection.macro == :has_and_belongs_to_many ? reflection.options[:join_table] : reflection.through_reflection.klass.table_name
|
|
unless join_dependency.table_aliases[aliased_join_table_name].zero?
|
|
@aliased_join_table_name = active_record.connection.table_alias_for "#{pluralize(reflection.name)}_#{parent_table_name}_join"
|
|
table_index = join_dependency.table_aliases[aliased_join_table_name]
|
|
join_dependency.table_aliases[aliased_join_table_name] += 1
|
|
@aliased_join_table_name = @aliased_join_table_name[0..active_record.connection.table_alias_length-3] + "_#{table_index+1}" if table_index > 0
|
|
else
|
|
join_dependency.table_aliases[aliased_join_table_name] += 1
|
|
end
|
|
end
|
|
end
|
|
|
|
def association_join
|
|
join = case reflection.macro
|
|
when :has_and_belongs_to_many
|
|
" LEFT OUTER JOIN %s ON %s.%s = %s.%s " % [
|
|
table_alias_for(options[:join_table], aliased_join_table_name),
|
|
aliased_join_table_name,
|
|
options[:foreign_key] || reflection.active_record.to_s.classify.foreign_key,
|
|
parent.aliased_table_name, reflection.active_record.primary_key] +
|
|
" LEFT OUTER JOIN %s ON %s.%s = %s.%s " % [
|
|
table_name_and_alias, aliased_table_name, klass.primary_key,
|
|
aliased_join_table_name, options[:association_foreign_key] || klass.table_name.classify.foreign_key
|
|
]
|
|
when :has_many, :has_one
|
|
case
|
|
when reflection.macro == :has_many && reflection.options[:through]
|
|
through_conditions = through_reflection.options[:conditions] ? "AND #{interpolate_sql(sanitize_sql(through_reflection.options[:conditions]))}" : ''
|
|
|
|
jt_foreign_key = jt_as_extra = jt_source_extra = jt_sti_extra = nil
|
|
first_key = second_key = as_extra = nil
|
|
|
|
if through_reflection.options[:as] # has_many :through against a polymorphic join
|
|
jt_foreign_key = through_reflection.options[:as].to_s + '_id'
|
|
jt_as_extra = " AND %s.%s = %s" % [
|
|
aliased_join_table_name, reflection.active_record.connection.quote_column_name(through_reflection.options[:as].to_s + '_type'),
|
|
klass.quote_value(parent.active_record.base_class.name)
|
|
]
|
|
else
|
|
jt_foreign_key = through_reflection.primary_key_name
|
|
end
|
|
|
|
case source_reflection.macro
|
|
when :has_many
|
|
if source_reflection.options[:as]
|
|
first_key = "#{source_reflection.options[:as]}_id"
|
|
second_key = options[:foreign_key] || primary_key
|
|
as_extra = " AND %s.%s = %s" % [
|
|
aliased_table_name, reflection.active_record.connection.quote_column_name("#{source_reflection.options[:as]}_type"),
|
|
klass.quote_value(source_reflection.active_record.base_class.name)
|
|
]
|
|
else
|
|
first_key = through_reflection.klass.base_class.to_s.classify.foreign_key
|
|
second_key = options[:foreign_key] || primary_key
|
|
end
|
|
|
|
unless through_reflection.klass.descends_from_active_record?
|
|
jt_sti_extra = " AND %s.%s = %s" % [
|
|
aliased_join_table_name,
|
|
reflection.active_record.connection.quote_column_name(through_reflection.active_record.inheritance_column),
|
|
through_reflection.klass.quote_value(through_reflection.klass.name.demodulize)]
|
|
end
|
|
when :belongs_to
|
|
first_key = primary_key
|
|
if reflection.options[:source_type]
|
|
second_key = source_reflection.association_foreign_key
|
|
jt_source_extra = " AND %s.%s = %s" % [
|
|
aliased_join_table_name, reflection.active_record.connection.quote_column_name(reflection.source_reflection.options[:foreign_type]),
|
|
klass.quote_value(reflection.options[:source_type])
|
|
]
|
|
else
|
|
second_key = source_reflection.options[:foreign_key] || klass.to_s.classify.foreign_key
|
|
end
|
|
end
|
|
|
|
" LEFT OUTER JOIN %s ON (%s.%s = %s.%s%s%s%s) " % [
|
|
table_alias_for(through_reflection.klass.table_name, aliased_join_table_name),
|
|
parent.aliased_table_name, reflection.active_record.connection.quote_column_name(parent.primary_key),
|
|
aliased_join_table_name, reflection.active_record.connection.quote_column_name(jt_foreign_key),
|
|
jt_as_extra, jt_source_extra, jt_sti_extra
|
|
] +
|
|
" LEFT OUTER JOIN %s ON (%s.%s = %s.%s%s) " % [
|
|
table_name_and_alias,
|
|
aliased_table_name, reflection.active_record.connection.quote_column_name(first_key),
|
|
aliased_join_table_name, reflection.active_record.connection.quote_column_name(second_key),
|
|
as_extra
|
|
]
|
|
|
|
when reflection.macro == :has_many && reflection.options[:as]
|
|
" LEFT OUTER JOIN %s ON %s.%s = %s.%s AND %s.%s = %s" % [
|
|
table_name_and_alias,
|
|
aliased_table_name, "#{reflection.options[:as]}_id",
|
|
parent.aliased_table_name, parent.primary_key,
|
|
aliased_table_name, "#{reflection.options[:as]}_type",
|
|
klass.quote_value(parent.active_record.base_class.name)
|
|
]
|
|
when reflection.macro == :has_one && reflection.options[:as]
|
|
" LEFT OUTER JOIN %s ON %s.%s = %s.%s AND %s.%s = %s " % [
|
|
table_name_and_alias,
|
|
aliased_table_name, "#{reflection.options[:as]}_id",
|
|
parent.aliased_table_name, parent.primary_key,
|
|
aliased_table_name, "#{reflection.options[:as]}_type",
|
|
klass.quote_value(reflection.active_record.base_class.name)
|
|
]
|
|
else
|
|
foreign_key = options[:foreign_key] || reflection.active_record.name.foreign_key
|
|
" LEFT OUTER JOIN %s ON %s.%s = %s.%s " % [
|
|
table_name_and_alias,
|
|
aliased_table_name, foreign_key,
|
|
parent.aliased_table_name, parent.primary_key
|
|
]
|
|
end
|
|
when :belongs_to
|
|
" LEFT OUTER JOIN %s ON %s.%s = %s.%s " % [
|
|
table_name_and_alias, aliased_table_name, reflection.klass.primary_key,
|
|
parent.aliased_table_name, options[:foreign_key] || klass.to_s.foreign_key
|
|
]
|
|
else
|
|
""
|
|
end || ''
|
|
join << %(AND %s.%s = %s ) % [
|
|
aliased_table_name,
|
|
reflection.active_record.connection.quote_column_name(klass.inheritance_column),
|
|
klass.quote_value(klass.name.demodulize)] unless klass.descends_from_active_record?
|
|
|
|
[through_reflection, reflection].each do |ref|
|
|
join << "AND #{interpolate_sql(sanitize_sql(ref.options[:conditions]))} " if ref && ref.options[:conditions]
|
|
end
|
|
|
|
join
|
|
end
|
|
|
|
protected
|
|
|
|
def pluralize(table_name)
|
|
ActiveRecord::Base.pluralize_table_names ? table_name.to_s.pluralize : table_name
|
|
end
|
|
|
|
def table_alias_for(table_name, table_alias)
|
|
"#{table_name} #{table_alias if table_name != table_alias}".strip
|
|
end
|
|
|
|
def table_name_and_alias
|
|
table_alias_for table_name, @aliased_table_name
|
|
end
|
|
|
|
def interpolate_sql(sql)
|
|
instance_eval("%@#{sql.gsub('@', '\@')}@")
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|