module ActiveModel module Validations class FormatValidator < EachValidator def validate_each(record, attribute, value) if options[:with] && value.to_s !~ options[:with] record.errors.add(attribute, :invalid, :default => options[:message], :value => value) elsif options[:without] && value.to_s =~ options[:without] record.errors.add(attribute, :invalid, :default => options[:message], :value => value) end end def check_validity! unless options.include?(:with) ^ options.include?(:without) # ^ == xor, or "exclusive or" raise ArgumentError, "Either :with or :without must be supplied (but not both)" end if options[:with] && !options[:with].is_a?(Regexp) raise ArgumentError, "A regular expression must be supplied as the :with option of the configuration hash" end if options[:without] && !options[:without].is_a?(Regexp) raise ArgumentError, "A regular expression must be supplied as the :without option of the configuration hash" end end end module HelperMethods # Validates whether the value of the specified attribute is of the correct form, going by the regular expression provided. # You can require that the attribute matches the regular expression: # # class Person < ActiveRecord::Base # validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i, :on => :create # end # # Alternatively, you can require that the specified attribute does _not_ match the regular expression: # # class Person < ActiveRecord::Base # validates_format_of :email, :without => /NOSPAM/ # end # # Note: use \A and \Z to match the start and end of the string, ^ and $ match the start/end of a line. # # You must pass either :with or :without as an option. In addition, both must be a regular expression, # or else an exception will be raised. # # Configuration options: # * :message - A custom error message (default is: "is invalid"). # * :allow_nil - If set to true, skips this validation if the attribute is +nil+ (default is +false+). # * :allow_blank - If set to true, skips this validation if the attribute is blank (default is +false+). # * :with - Regular expression that if the attribute matches will result in a successful validation. # * :without - Regular expression that if the attribute does not match will result in a successful validation. # * :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_format_of(*attr_names) validates_with FormatValidator, _merge_attributes(attr_names) end end end end