require 'active_support/core_ext/array/extract_options'
require 'active_support/core_ext/hash/keys'
require 'active_support/core_ext/hash/except'
module ActiveModel
# == Active \Model \Validations
#
# Provides a full validation framework to your objects.
#
# A minimal implementation could be:
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :first_name, :last_name
#
# validates_each :first_name, :last_name do |record, attr, value|
# record.errors.add attr, 'starts with z.' if value.to_s[0] == ?z
# end
# end
#
# Which provides you with the full standard validation stack that you
# know from Active Record:
#
# person = Person.new
# person.valid? # => true
# person.invalid? # => false
#
# person.first_name = 'zoolander'
# person.valid? # => false
# person.invalid? # => true
# person.errors.messages # => {first_name:["starts with z."]}
#
# Note that <tt>ActiveModel::Validations</tt> automatically adds an +errors+
# method to your instances initialized with a new <tt>ActiveModel::Errors</tt>
# object, so there is no need for you to do this manually.
module Validations
extend ActiveSupport::Concern
included do
extend ActiveModel::Naming
extend ActiveModel::Callbacks
extend ActiveModel::Translation
extend HelperMethods
include HelperMethods
attr_accessor :validation_context
define_callbacks :validate, scope: :name
class_attribute :_validators
self._validators = Hash.new { |h,k| h[k] = [] }
end
module ClassMethods
# Validates each attribute against a block.
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :first_name, :last_name
#
# validates_each :first_name, :last_name, allow_blank: true do |record, attr, value|
# record.errors.add attr, 'starts with z.' if value.to_s[0] == ?z
# end
# end
#
# Options:
# * <tt>:on</tt> - Specifies the contexts where this validation is active.
# Runs in all validation contexts by default (nil). You can pass a symbol
# or an array of symbols. (e.g. <tt>on: :create</tt> or
# <tt>on: :custom_validation_context</tt> or
# <tt>on: [:create, :custom_validation_context]</tt>)
# * <tt>:allow_nil</tt> - Skip validation if attribute is +nil+.
# * <tt>:allow_blank</tt> - Skip validation if attribute is blank.
# * <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_each(*attr_names, &block)
validates_with BlockValidator, _merge_attributes(attr_names), &block
end
VALID_OPTIONS_FOR_VALIDATE = [:on, :if, :unless, :prepend].freeze # :nodoc:
# Adds a validation method or block to the class. This is useful when
# overriding the +validate+ instance method becomes too unwieldy and
# you're looking for more descriptive declaration of your validations.
#
# This can be done with a symbol pointing to a method:
#
# class Comment
# include ActiveModel::Validations
#
# validate :must_be_friends
#
# def must_be_friends
# errors.add(:base, 'Must be friends to leave a comment') unless commenter.friend_of?(commentee)
# end
# end
#
# With a block which is passed with the current record to be validated:
#
# class Comment
# include ActiveModel::Validations
#
# validate do |comment|
# comment.must_be_friends
# end
#
# def must_be_friends
# errors.add(:base, 'Must be friends to leave a comment') unless commenter.friend_of?(commentee)
# end
# end
#
# Or with a block where self points to the current record to be validated:
#
# class Comment
# include ActiveModel::Validations
#
# validate do
# errors.add(:base, 'Must be friends to leave a comment') unless commenter.friend_of?(commentee)
# end
# end
#
# Note that the return value of validation methods is not relevant.
# It's not possible to halt the validate callback chain.
#
# Options:
# * <tt>:on</tt> - Specifies the contexts where this validation is active.
# Runs in all validation contexts by default (nil). You can pass a symbol
# or an array of symbols. (e.g. <tt>on: :create</tt> or
# <tt>on: :custom_validation_context</tt> or
# <tt>on: [:create, :custom_validation_context]</tt>)
# * <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 validate(*args, &block)
options = args.extract_options!
if args.all? { |arg| arg.is_a?(Symbol) }
options.each_key do |k|
unless VALID_OPTIONS_FOR_VALIDATE.include?(k)
raise ArgumentError.new("Unknown key: #{k.inspect}. Valid keys are: #{VALID_OPTIONS_FOR_VALIDATE.map(&:inspect).join(', ')}. Perhaps you meant to call `validates` instead of `validate`?")
end
end
end
if options.key?(:on)
options = options.dup
options[:if] = Array(options[:if])
options[:if].unshift ->(o) {
!(Array(options[:on]) & Array(o.validation_context)).empty?
}
end
args << options
set_callback(:validate, *args, &block)
end
# List all validators that are being used to validate the model using
# +validates_with+ method.
#
# class Person
# include ActiveModel::Validations
#
# validates_with MyValidator
# validates_with OtherValidator, on: :create
# validates_with StrictValidator, strict: true
# end
#
# Person.validators
# # => [
# # #<MyValidator:0x007fbff403e808 @options={}>,
# # #<OtherValidator:0x007fbff403d930 @options={on: :create}>,
# # #<StrictValidator:0x007fbff3204a30 @options={strict:true}>
# # ]
def validators
_validators.values.flatten.uniq
end
# Clears all of the validators and validations.
#
# Note that this will clear anything that is being used to validate
# the model for both the +validates_with+ and +validate+ methods.
# It clears the validators that are created with an invocation of
# +validates_with+ and the callbacks that are set by an invocation
# of +validate+.
#
# class Person
# include ActiveModel::Validations
#
# validates_with MyValidator
# validates_with OtherValidator, on: :create
# validates_with StrictValidator, strict: true
# validate :cannot_be_robot
#
# def cannot_be_robot
# errors.add(:base, 'A person cannot be a robot') if person_is_robot
# end
# end
#
# Person.validators
# # => [
# # #<MyValidator:0x007fbff403e808 @options={}>,
# # #<OtherValidator:0x007fbff403d930 @options={on: :create}>,
# # #<StrictValidator:0x007fbff3204a30 @options={strict:true}>
# # ]
#
# If one runs <tt>Person.clear_validators!</tt> and then checks to see what
# validators this class has, you would obtain:
#
# Person.validators # => []
#
# Also, the callback set by <tt>validate :cannot_be_robot</tt> will be erased
# so that:
#
# Person._validate_callbacks.empty? # => true
#
def clear_validators!
reset_callbacks(:validate)
_validators.clear
end
# List all validators that are being used to validate a specific attribute.
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name , :age
#
# validates_presence_of :name
# validates_inclusion_of :age, in: 0..99
# end
#
# Person.validators_on(:name)
# # => [
# # #<ActiveModel::Validations::PresenceValidator:0x007fe604914e60 @attributes=[:name], @options={}>,
# # ]
def validators_on(*attributes)
attributes.flat_map do |attribute|
_validators[attribute.to_sym]
end
end
# Returns +true+ if +attribute+ is an attribute method, +false+ otherwise.
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name
# end
#
# User.attribute_method?(:name) # => true
# User.attribute_method?(:age) # => false
def attribute_method?(attribute)
method_defined?(attribute)
end
# Copy validators on inheritance.
def inherited(base) #:nodoc:
dup = _validators.dup
base._validators = dup.each { |k, v| dup[k] = v.dup }
super
end
end
# Clean the +Errors+ object if instance is duped.
def initialize_dup(other) #:nodoc:
@errors = nil
super
end
# Returns the +Errors+ object that holds all information about attribute
# error messages.
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name
# validates_presence_of :name
# end
#
# person = Person.new
# person.valid? # => false
# person.errors # => #<ActiveModel::Errors:0x007fe603816640 @messages={name:["can't be blank"]}>
def errors
@errors ||= Errors.new(self)
end
# Runs all the specified validations and returns +true+ if no errors were
# added otherwise +false+.
#
# Aliased as validate.
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name
# validates_presence_of :name
# end
#
# person = Person.new
# person.name = ''
# person.valid? # => false
# person.name = 'david'
# person.valid? # => true
#
# Context can optionally be supplied to define which callbacks to test
# against (the context is defined on the validations using <tt>:on</tt>).
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name
# validates_presence_of :name, on: :new
# end
#
# person = Person.new
# person.valid? # => true
# person.valid?(:new) # => false
def valid?(context = nil)
current_context, self.validation_context = validation_context, context
errors.clear
run_validations!
ensure
self.validation_context = current_context
end
alias_method :validate, :valid?
# Performs the opposite of <tt>valid?</tt>. Returns +true+ if errors were
# added, +false+ otherwise.
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name
# validates_presence_of :name
# end
#
# person = Person.new
# person.name = ''
# person.invalid? # => true
# person.name = 'david'
# person.invalid? # => false
#
# Context can optionally be supplied to define which callbacks to test
# against (the context is defined on the validations using <tt>:on</tt>).
#
# class Person
# include ActiveModel::Validations
#
# attr_accessor :name
# validates_presence_of :name, on: :new
# end
#
# person = Person.new
# person.invalid? # => false
# person.invalid?(:new) # => true
def invalid?(context = nil)
!valid?(context)
end
# Runs all the validations within the specified context. Returns +true+ if
# no errors are found, raises +ValidationError+ otherwise.
#
# Validations with no <tt>:on</tt> option will run no matter the context. Validations with
# some <tt>:on</tt> option will only run in the specified context.
def validate!(context = nil)
valid?(context) || raise_validation_error
end
# Hook method defining how an attribute value should be retrieved. By default
# this is assumed to be an instance named after the attribute. Override this
# method in subclasses should you need to retrieve the value for a given
# attribute differently:
#
# class MyClass
# include ActiveModel::Validations
#
# def initialize(data = {})
# @data = data
# end
#
# def read_attribute_for_validation(key)
# @data[key]
# end
# end
alias :read_attribute_for_validation :send
protected
def run_validations! #:nodoc:
_run_validate_callbacks
errors.empty?
end
def raise_validation_error
raise(ValidationError.new(self))
end
end
# = Active Model ValidationError
#
# Raised by <tt>validate!</tt> when the model is invalid. Use the
# +model+ method to retrieve the record which did not validate.
#
# begin
# complex_operation_that_internally_calls_validate!
# rescue ActiveModel::ValidationError => invalid
# puts invalid.model.errors
# end
class ValidationError < StandardError
attr_reader :model
def initialize(model)
@model = model
errors = @model.errors.full_messages.join(", ")
super(I18n.t(:"#{@model.class.i18n_scope}.errors.messages.model_invalid", errors: errors, default: :"errors.messages.model_invalid"))
end
end
end
Dir[File.dirname(__FILE__) + "/validations/*.rb"].each { |file| require file }
