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Diffstat (limited to 'activemodel/lib/active_model/validations.rb')
| -rw-r--r-- | activemodel/lib/active_model/validations.rb | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/activemodel/lib/active_model/validations.rb b/activemodel/lib/active_model/validations.rb new file mode 100644 index 0000000000..f67a3be5c1 --- /dev/null +++ b/activemodel/lib/active_model/validations.rb @@ -0,0 +1,392 @@ +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::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. + # 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 + + # 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 + # + # Options: + # * <tt>:on</tt> - Specifies the contexts where this validation is active. + # 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.assert_valid_keys([:on, :if, :unless]) + end + + if options.key?(:on) + options = options.dup + options[:if] = Array(options[:if]) + options[:if].unshift lambda { |o| + Array(options[:on]).include?(o.validation_context) + } + 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 + + # 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_callbacks :validate + errors.empty? + end + end +end + +Dir[File.dirname(__FILE__) + "/validations/*.rb"].each { |file| require file } |