require 'active_support/core_ext/string/inflections'
require 'active_support/ordered_hash'
module ActiveModel
# Provides a modified +OrderedHash+ that you can include in your object
# for handling error messages and interacting with Action Pack helpers.
#
# A minimal implementation could be:
#
# class Person
#
# # Required dependency for ActiveModel::Errors
# extend ActiveModel::Naming
#
# def initialize
# @errors = ActiveModel::Errors.new(self)
# end
#
# attr_accessor :name
# attr_reader :errors
#
# def validate!
# errors.add(:name, "can not be nil") if name == nil
# end
#
# # The following methods are needed to be minimally implemented
#
# def read_attribute_for_validation(attr)
# send(attr)
# end
#
# def ErrorsPerson.human_attribute_name(attr, options = {})
# attr
# end
#
# def ErrorsPerson.lookup_ancestors
# [self]
# end
#
# end
#
# The last three methods are required in your object for Errors to be
# able to generate error messages correctly and also handle multiple
# languages. Of course, if you extend your object with ActiveModel::Translations
# you will not need to implement the last two. Likewise, using
# ActiveModel::Validations will handle the validation related methods
# for you.
#
# The above allows you to do:
#
# p = Person.new
# p.validate! # => ["can not be nil"]
# p.errors.full_messages # => ["name can not be nil"]
# # etc..
class Errors < ActiveSupport::OrderedHash
include DeprecatedErrorMethods
# Pass in the instance of the object that is using the errors object.
#
# class Person
# def initialize
# @errors = ActiveModel::Errors.new(self)
# end
# end
def initialize(base)
@base = base
super()
end
alias_method :get, :[]
alias_method :set, :[]=
# When passed a symbol or a name of a method, returns an array of errors for the method.
#
# p.errors[:name] #=> ["can not be nil"]
# p.errors['name'] #=> ["can not be nil"]
def [](attribute)
if errors = get(attribute.to_sym)
errors
else
set(attribute.to_sym, [])
end
end
# Adds to the supplied attribute the supplied error message.
#
# p.errors[:name] = "must be set"
# p.errors[:name] #=> ['must be set']
def []=(attribute, error)
self[attribute.to_sym] << error
end
# Iterates through each error key, value pair in the error messages hash.
# Yields the attribute and the error for that attribute. If the attribute
# has more than one error message, yields once for each error message.
#
# p.errors.add(:name, "can't be blank")
# p.errors.each do |attribute, errors_array|
# # Will yield :name and "can't be blank"
# end
#
# p.errors.add(:name, "must be specified")
# p.errors.each do |attribute, errors_array|
# # Will yield :name and "can't be blank"
# # then yield :name and "must be specified"
# end
def each
each_key do |attribute|
self[attribute].each { |error| yield attribute, error }
end
end
# Returns the number of error messages.
#
# p.errors.add(:name, "can't be blank")
# p.errors.size #=> 1
# p.errors.add(:name, "must be specified")
# p.errors.size #=> 2
def size
values.flatten.size
end
# Returns an array of error messages, with the attribute name included
#
# p.errors.add(:name, "can't be blank")
# p.errors.add(:name, "must be specified")
# p.errors.to_a #=> ["name can't be blank", "name must be specified"]
def to_a
full_messages
end
# Returns the number of error messages.
# p.errors.add(:name, "can't be blank")
# p.errors.count #=> 1
# p.errors.add(:name, "must be specified")
# p.errors.count #=> 2
def count
to_a.size
end
# Returns an xml formatted representation of the Errors hash.
#
# p.errors.add(:name, "can't be blank")
# p.errors.add(:name, "must be specified")
# p.errors.to_xml #=> Produces:
#
# #
# #
# # name can't be blank
# # name must be specified
# #
def to_xml(options={})
require 'builder' unless defined? ::Builder
options[:root] ||= "errors"
options[:indent] ||= 2
options[:builder] ||= ::Builder::XmlMarkup.new(:indent => options[:indent])
options[:builder].instruct! unless options.delete(:skip_instruct)
options[:builder].errors do |e|
to_a.each { |error| e.error(error) }
end
end
# Adds an error message (+messsage+) to the +attribute+, which will be returned on a call to on(attribute)
# for the same attribute and ensure that this error object returns false when asked if empty?. More than one
# error can be added to the same +attribute+ in which case an array will be returned on a call to on(attribute).
# If no +messsage+ is supplied, :invalid is assumed.
#
# If +message+ is a Symbol, it will be translated, using the appropriate scope (see translate_error).
# If +message+ is a Proc, it will be called, allowing for things like Time.now to be used within an error
def add(attribute, message = nil, options = {})
message ||= :invalid
message = generate_message(attribute, message, options) if message.is_a?(Symbol)
message = message.call if message.is_a?(Proc)
self[attribute] << message
end
# Will add an error message to each of the attributes in +attributes+ that is empty.
def add_on_empty(attributes, custom_message = nil)
[attributes].flatten.each do |attribute|
value = @base.send(:read_attribute_for_validation, attribute)
is_empty = value.respond_to?(:empty?) ? value.empty? : false
add(attribute, :empty, :default => custom_message) unless !value.nil? && !is_empty
end
end
# Will add an error message to each of the attributes in +attributes+ that is blank (using Object#blank?).
def add_on_blank(attributes, custom_message = nil)
[attributes].flatten.each do |attribute|
value = @base.send(:read_attribute_for_validation, attribute)
add(attribute, :blank, :default => custom_message) if value.blank?
end
end
# Returns all the full error messages in an array.
#
# class Company
# validates_presence_of :name, :address, :email
# validates_length_of :name, :in => 5..30
# end
#
# company = Company.create(:address => '123 First St.')
# company.errors.full_messages # =>
# ["Name is too short (minimum is 5 characters)", "Name can't be blank", "Address can't be blank"]
def full_messages
full_messages = []
each do |attribute, messages|
messages = Array(messages)
next if messages.empty?
if attribute == :base
messages.each {|m| full_messages << m }
else
attr_name = attribute.to_s.gsub('.', '_').humanize
attr_name = @base.class.human_attribute_name(attribute, :default => attr_name)
options = { :default => "{{attribute}} {{message}}", :attribute => attr_name }
messages.each do |m|
full_messages << I18n.t(:"errors.format", options.merge(:message => m))
end
end
end
full_messages
end
# Translates an error message in its default scope (activemodel.errors.messages).
# Error messages are first looked up in models.MODEL.attributes.ATTRIBUTE.MESSAGE, if it's not there,
# it's looked up in models.MODEL.MESSAGE and if that is not there it returns the translation of the
# default message (e.g. activemodel.errors.messages.MESSAGE). The translated model name,
# translated attribute name and the value are available for interpolation.
#
# When using inheritence in your models, it will check all the inherited models too, but only if the model itself
# hasn't been found. Say you have class Admin < User; end and you wanted the translation for the :blank
# error +message+ for the title +attribute+, it looks for these translations:
#
#
# - activemodel.errors.models.admin.attributes.title.blank
# - activemodel.errors.models.admin.blank
# - activemodel.errors.models.user.attributes.title.blank
# - activemodel.errors.models.user.blank
# - any default you provided through the +options+ hash (in the activemodel.errors scope)
# - activemodel.errors.messages.blank
# - errors.attributes.title.blank
# - errors.messages.blank
#
def generate_message(attribute, message = :invalid, options = {})
message, options[:default] = options[:default], message if options[:default].is_a?(Symbol)
defaults = @base.class.lookup_ancestors.map do |klass|
[ :"#{@base.class.i18n_scope}.errors.models.#{klass.model_name.underscore}.attributes.#{attribute}.#{message}",
:"#{@base.class.i18n_scope}.errors.models.#{klass.model_name.underscore}.#{message}" ]
end
defaults << options.delete(:default)
defaults << :"#{@base.class.i18n_scope}.errors.messages.#{message}"
defaults << :"errors.attributes.#{attribute}.#{message}"
defaults << :"errors.messages.#{message}"
defaults.compact!
defaults.flatten!
key = defaults.shift
value = @base.send(:read_attribute_for_validation, attribute)
options = {
:default => defaults,
:model => @base.class.model_name.human,
:attribute => @base.class.human_attribute_name(attribute),
:value => value
}.merge(options)
I18n.translate(key, options)
end
end
end