module ActiveModel module Validations module ClassMethods # Encapsulates the pattern of wanting to validate the acceptance of a terms of service check box (or similar agreement). Example: # # class Person < ActiveRecord::Base # validates_acceptance_of :terms_of_service # validates_acceptance_of :eula, :message => "must be abided" # end # # If the database column does not exist, the terms_of_service attribute is entirely virtual. This check is # performed only if terms_of_service is not nil and by default on save. # # Configuration options: # * message - A custom error message (default is: "must be accepted") # * on - Specifies when this validation is active (default is :save, other options :create, :update) # * allow_nil - Skip validation if attribute is nil. (default is true) # * accept - Specifies value that is considered accepted. The default value is a string "1", which # makes it easy to relate to an HTML checkbox. This should be set to 'true' if you are validating a database # column, since the attribute is typecast from "1" to true before validation. # * 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_acceptance_of(*attr_names) configuration = { :message => ActiveRecord::Errors.default_error_messages[:accepted], :on => :save, :allow_nil => true, :accept => "1" } configuration.update(attr_names.extract_options!) db_cols = begin column_names rescue ActiveRecord::StatementInvalid [] end names = attr_names.reject { |name| db_cols.include?(name.to_s) } attr_accessor(*names) validates_each(attr_names,configuration) do |record, attr_name, value| record.errors.add(attr_name, configuration[:message]) unless value == configuration[:accept] end end end end end