module ActiveModel module Validations module ClassMethods # Validates whether the associated object or objects are all valid themselves. Works with any kind of association. # # class Book < ActiveRecord::Base # has_many :pages # belongs_to :library # # validates_associated :pages, :library # end # # Warning: If, after the above definition, you then wrote: # # class Page < ActiveRecord::Base # belongs_to :book # # validates_associated :book # end # # ...this would specify a circular dependency and cause infinite recursion. # # NOTE: This validation will not fail if the association hasn't been assigned. If you want to ensure that the association # is both present and guaranteed to be valid, you also need to use validates_presence_of. # # Configuration options: # * message - A custom error message (default is: "is invalid") # * on Specifies when this validation is active (default is :save, other options :create, :update) # * if - Specifies a method, proc or string to call to determine if the validation should # occur (e.g. :if => :allow_validation, or :if => Proc.new { |user| user.signup_step > 2 }). The # method, proc or string should return or evaluate to a true or false value. # * unless - Specifies a method, proc or string to call to determine if the validation should # not occur (e.g. :unless => :skip_validation, or :unless => Proc.new { |user| user.signup_step <= 2 }). The # method, proc or string should return or evaluate to a true or false value. def validates_associated(*attr_names) configuration = { :message => ActiveRecord::Errors.default_error_messages[:invalid], :on => :save } configuration.update(attr_names.extract_options!) validates_each(attr_names, configuration) do |record, attr_name, value| record.errors.add(attr_name, configuration[:message]) unless (value.is_a?(Array) ? value : [value]).inject(true) { |v, r| (r.nil? || r.valid?) && v } end end end end end