module ActiveRecord::Associations::Builder
class BelongsTo < SingularAssociation #:nodoc:
def self.macro
:belongs_to
end
def self.valid_options(options)
super + [:foreign_type, :polymorphic, :touch]
end
def self.valid_dependent_options
[:destroy, :delete]
end
def self.define_callbacks(model, reflection)
super
add_counter_cache_callbacks(model, reflection) if reflection.options[:counter_cache]
add_touch_callbacks(model, reflection) if reflection.options[:touch]
end
def self.define_accessors(mixin, reflection)
super
add_counter_cache_methods mixin
end
def self.add_counter_cache_methods(mixin)
return if mixin.method_defined? :belongs_to_counter_cache_after_create
mixin.class_eval do
def belongs_to_counter_cache_after_create(reflection)
if record = send(reflection.name)
cache_column = reflection.counter_cache_column
record.class.increment_counter(cache_column, record.id)
@_after_create_counter_called = true
end
end
def belongs_to_counter_cache_before_destroy(reflection)
foreign_key = reflection.foreign_key.to_sym
unless destroyed_by_association && destroyed_by_association.foreign_key.to_sym == foreign_key
record = send reflection.name
if record && !self.destroyed?
cache_column = reflection.counter_cache_column
record.class.decrement_counter(cache_column, record.id)
end
end
end
def belongs_to_counter_cache_after_update(reflection)
foreign_key = reflection.foreign_key
cache_column = reflection.counter_cache_column
if (@_after_create_counter_called ||= false)
@_after_create_counter_called = false
elsif attribute_changed?(foreign_key) && !new_record? && reflection.constructable?
model = reflection.klass
foreign_key_was = attribute_was foreign_key
foreign_key = attribute foreign_key
if foreign_key && model.respond_to?(:increment_counter)
model.increment_counter(cache_column, foreign_key)
end
if foreign_key_was && model.respond_to?(:decrement_counter)
model.decrement_counter(cache_column, foreign_key_was)
end
end
end
end
end
def self.add_counter_cache_callbacks(model, reflection)
cache_column = reflection.counter_cache_column
model.after_create lambda { |record|
record.belongs_to_counter_cache_after_create(reflection)
}
model.before_destroy lambda { |record|
record.belongs_to_counter_cache_before_destroy(reflection)
}
model.after_update lambda { |record|
record.belongs_to_counter_cache_after_update(reflection)
}
klass = reflection.class_name.safe_constantize
klass.attr_readonly cache_column if klass && klass.respond_to?(:attr_readonly)
end
def self.touch_record(o, foreign_key, name, touch) # :nodoc:
old_foreign_id = o.changed_attributes[foreign_key]
if old_foreign_id
klass = o.association(name).klass
old_record = klass.find_by(klass.primary_key => old_foreign_id)
if old_record
if touch != true
old_record.touch touch
else
old_record.touch
end
end
end
record = o.send name
unless record.nil? || record.new_record?
if touch != true
record.touch touch
else
record.touch
end
end
end
def self.add_touch_callbacks(model, reflection)
foreign_key = reflection.foreign_key
n = reflection.name
touch = reflection.options[:touch]
callback = lambda { |record|
BelongsTo.touch_record(record, foreign_key, n, touch)
}
model.after_save callback
model.after_touch callback
model.after_destroy callback
end
end
end