require 'active_support/core_ext/hash/slice'
module ActiveModel
module Validations
module ClassMethods
# This method is a shortcut to all default validators and any custom
# validator classes ending in 'Validator'. Note that Rails default
# validators can be overridden inside specific classes by creating
# custom validator classes in their place such as PresenceValidator.
#
# Examples of using the default rails validators:
#
# validates :terms, :acceptance => true
# validates :password, :confirmation => true
# validates :username, :exclusion => { :in => %w(admin superuser) }
# validates :email, :format => { :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i, :on => :create }
# validates :age, :inclusion => { :in => 0..9 }
# validates :first_name, :length => { :maximum => 30 }
# validates :age, :numericality => true
# validates :username, :presence => true
# validates :username, :uniqueness => true
#
# The power of the +validates+ method comes when using cusom validators
# and default validators in one call for a given attribute e.g.
#
# class EmailValidator < ActiveModel::EachValidator
# def validate_each(record, attribute, value)
# record.errors[attribute] << (options[:message] || "is not an email") unless
# value =~ /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/i
# end
# end
#
# class Person
# include ActiveModel::Validations
# attr_accessor :name, :email
#
# validates :name, :presence => true, :uniqueness => true, :length => { :maximum => 100 }
# validates :email, :presence => true, :email => true
# end
#
# Validator classes my also exist within the class being validated
# allowing custom modules of validators to be included as needed e.g.
#
# class Film
# include ActiveModel::Validations
#
# class TitleValidator < ActiveModel::EachValidator
# def validate_each(record, attribute, value)
# record.errors[attribute] << "must start with 'the'" unless =~ /^the/i
# end
# end
#
# validates :name, :title => true
# end
#
# The validators hash can also handle regular expressions, ranges and arrays:
#
# validates :email, :format => /@/
# validates :gender, :inclusion => %w(male female)
# validates :password, :length => 6..20
#
# Finally, the options :if, :unless, :on, :allow_blank and :allow_nil can be given
# to one specific validator:
#
# validates :password, :presence => { :if => :password_required? }, :confirmation => true
#
# Or to all at the same time:
#
# validates :password, :presence => true, :confirmation => true, :if => :password_required?
#
def validates(*attributes)
defaults = attributes.extract_options!
validations = defaults.slice!(:if, :unless, :on, :allow_blank, :allow_nil)
raise ArgumentError, "You need to supply at least one attribute" if attributes.empty?
raise ArgumentError, "Attribute names must be symbols" if attributes.any?{ |attribute| !attribute.is_a?(Symbol) }
raise ArgumentError, "You need to supply at least one validation" if validations.empty?
defaults.merge!(:attributes => attributes)
validations.each do |key, options|
begin
validator = const_get("#{key.to_s.camelize}Validator")
rescue NameError
raise ArgumentError, "Unknown validator: '#{key}'"
end
validates_with(validator, defaults.merge(_parse_validates_options(options)))
end
end
protected
def _parse_validates_options(options) #:nodoc:
case options
when TrueClass
{}
when Hash
options
when Regexp
{ :with => options }
when Range, Array
{ :in => options }
end
end
end
end
end
