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 <tt>:terms_of_service</tt> attribute is entirely virtual. This check is # performed only if <tt>:terms_of_service</tt> is not +nil+ and by default on save. # # Configuration options: # * <tt>:message</tt> - A custom error message (default is: "must be accepted") # * <tt>:on</tt> - Specifies when this validation is active (default is <tt>:save</tt>, other options <tt>:create</tt>, <tt>:update</tt>) # * <tt>:allow_nil</tt> - Skip validation if attribute is +nil+. (default is +true+) # * <tt>:accept</tt> - 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 typecasted from "1" to +true+ before validation. # * <tt>:if</tt> - Specifies a method, proc or string to call to determine if the validation should # occur (e.g. <tt>:if => :allow_validation</tt>, or <tt>:if => Proc.new { |user| user.signup_step > 2 }</tt>). The # method, proc or string should return or evaluate to a true or false value. # * <tt>:unless</tt> - Specifies a method, proc or string to call to determine if the validation should # not occur (e.g. <tt>:unless => :skip_validation</tt>, or <tt>:unless => Proc.new { |user| user.signup_step <= 2 }</tt>). 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