module ActiveRecord::AutosaveAssociation::ClassMethods - activerecord-4.2.3 Documentation

# module ActiveRecord::AutosaveAssociation::ClassMethods

### Private Instance Methods

add_autosave_association_callbacks(reflection) click to toggle source

Adds validation and save callbacks for the association as specified by the `reflection`.

For performance reasons, we don't check whether to validate at runtime. However the validation and callback methods are lazy and those methods get created when they are invoked for the very first time. However, this can change, for instance, when using nested attributes, which is called after the association has been defined. Since we don't want the callbacks to get defined multiple times, there are guards that check if the save or validation methods have already been defined before actually defining them.

    # File lib/active_record/autosave_association.rb, line 178
    def add_autosave_association_callbacks(reflection)
      save_method = :"autosave_associated_records_for_#{reflection.name}"

      if reflection.collection?
        before_save :before_save_collection_association

        define_non_cyclic_method(save_method) { save_collection_association(reflection) }
        # Doesn't use after_save as that would save associations added in after_create/after_update twice
        after_create save_method
        after_update save_method
      elsif reflection.has_one?
        define_method(save_method) { save_has_one_association(reflection) } unless method_defined?(save_method)
        # Configures two callbacks instead of a single after_save so that
        # the model may rely on their execution order relative to its
        # own callbacks.
        #
        # For example, given that after_creates run before after_saves, if
        # we configured instead an after_save there would be no way to fire
        # a custom after_create callback after the child association gets
        # created.
        after_create save_method
        after_update save_method
      else
        define_non_cyclic_method(save_method) { save_belongs_to_association(reflection) }
        before_save save_method
      end

      define_autosave_validation_callbacks(reflection)
    end

define_autosave_validation_callbacks(reflection) click to toggle source

    # File lib/active_record/autosave_association.rb, line 208
    def define_autosave_validation_callbacks(reflection)
      validation_method = :"validate_associated_records_for_#{reflection.name}"
      if reflection.validate? && !method_defined?(validation_method)
        if reflection.collection?
          method = :validate_collection_association
        else
          method = :validate_single_association
        end

        define_non_cyclic_method(validation_method) { send(method, reflection) }
        validate validation_method
      end
    end

define_non_cyclic_method(name, &block) click to toggle source

    # File lib/active_record/autosave_association.rb, line 149
    def define_non_cyclic_method(name, &block)
      return if method_defined?(name)
      define_method(name) do |*args|
        result = true; @_already_called ||= {}
        # Loop prevention for validation of associations
        unless @_already_called[name]
          begin
            @_already_called[name]=true
            result = instance_eval(&block)
          ensure
            @_already_called[name]=false
          end
        end

        result
      end
    end