Module | ActiveRecord::Validations::ClassMethods |
In: |
vendor/rails/activerecord/lib/active_record/validations.rb
|
All of the following validations are defined in the class scope of the model that you‘re interested in validating. They offer a more declarative way of specifying when the model is valid and when it is not. It is recommended to use these over the low-level calls to validate and validate_on_create when possible.
DEFAULT_VALIDATION_OPTIONS | = | { :on => :save, :allow_nil => false, :allow_blank => false, :message => nil |
ALL_RANGE_OPTIONS | = | [ :is, :within, :in, :minimum, :maximum ].freeze |
ALL_NUMERICALITY_CHECKS | = | { :greater_than => '>', :greater_than_or_equal_to => '>=', :equal_to => '==', :less_than => '<', :less_than_or_equal_to => '<=', :odd => 'odd?', :even => 'even?' }.freeze |
Creates an object just like Base.create but calls save! instead of save so an exception is raised if the record is invalid.
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 876 876: def create!(attributes = nil, &block) 877: if attributes.is_a?(Array) 878: attributes.collect { |attr| create!(attr, &block) } 879: else 880: object = new(attributes) 881: yield(object) if block_given? 882: object.save! 883: object 884: end 885: end
Encapsulates the pattern of wanting to validate the acceptance of a terms of service check box (or similar agreement). Example:
class Person < ActiveRecord::Base validates_acceptance_of :terms_of_service validates_acceptance_of :eula, :message => "must be abided" end
If the database column does not exist, the terms_of_service attribute is entirely virtual. This check is performed only if terms_of_service is not nil and by default on save.
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 425 425: def validates_acceptance_of(*attr_names) 426: configuration = { :message => ActiveRecord::Errors.default_error_messages[:accepted], :on => :save, :allow_nil => true, :accept => "1" } 427: configuration.update(attr_names.extract_options!) 428: 429: db_cols = begin 430: column_names 431: rescue ActiveRecord::StatementInvalid 432: [] 433: end 434: names = attr_names.reject { |name| db_cols.include?(name.to_s) } 435: attr_accessor(*names) 436: 437: validates_each(attr_names,configuration) do |record, attr_name, value| 438: record.errors.add(attr_name, configuration[:message]) unless value == configuration[:accept] 439: end 440: end
Validates whether the associated object or objects are all valid themselves. Works with any kind of association.
class Book < ActiveRecord::Base has_many :pages belongs_to :library validates_associated :pages, :library end
Warning: If, after the above definition, you then wrote:
class Page < ActiveRecord::Base belongs_to :book validates_associated :book end
this would specify a circular dependency and cause infinite recursion.
NOTE: This validation will not fail if the association hasn‘t been assigned. If you want to ensure that the association is both present and guaranteed to be valid, you also need to use validates_presence_of.
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 794 794: def validates_associated(*attr_names) 795: configuration = { :message => ActiveRecord::Errors.default_error_messages[:invalid], :on => :save } 796: configuration.update(attr_names.extract_options!) 797: 798: validates_each(attr_names, configuration) do |record, attr_name, value| 799: record.errors.add(attr_name, configuration[:message]) unless 800: (value.is_a?(Array) ? value : [value]).inject(true) { |v, r| (r.nil? || r.valid?) && v } 801: end 802: end
Encapsulates the pattern of wanting to validate a password or email address field with a confirmation. Example:
Model: class Person < ActiveRecord::Base validates_confirmation_of :user_name, :password validates_confirmation_of :email_address, :message => "should match confirmation" end View: <%= password_field "person", "password" %> <%= password_field "person", "password_confirmation" %>
The added password_confirmation attribute is virtual; it exists only as an in-memory attribute for validating the password. To achieve this, the validation adds accessors to the model for the confirmation attribute. NOTE: This check is performed only if password_confirmation is not nil, and by default only on save. To require confirmation, make sure to add a presence check for the confirmation attribute:
validates_presence_of :password_confirmation, :if => :password_changed?
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 391 391: def validates_confirmation_of(*attr_names) 392: configuration = { :message => ActiveRecord::Errors.default_error_messages[:confirmation], :on => :save } 393: configuration.update(attr_names.extract_options!) 394: 395: attr_accessor(*(attr_names.map { |n| "#{n}_confirmation" })) 396: 397: validates_each(attr_names, configuration) do |record, attr_name, value| 398: record.errors.add(attr_name, configuration[:message]) unless record.send("#{attr_name}_confirmation").nil? or value == record.send("#{attr_name}_confirmation") 399: end 400: end
Validates each attribute against a block.
class Person < ActiveRecord::Base validates_each :first_name, :last_name do |record, attr, value| record.errors.add attr, 'starts with z.' if value[0] == ?z end end
Options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 349 349: def validates_each(*attrs) 350: options = attrs.extract_options!.symbolize_keys 351: attrs = attrs.flatten 352: 353: # Declare the validation. 354: send(validation_method(options[:on] || :save), options) do |record| 355: attrs.each do |attr| 356: value = record.send(attr) 357: next if (value.nil? && options[:allow_nil]) || (value.blank? && options[:allow_blank]) 358: yield record, attr, value 359: end 360: end 361: end
Validates that the value of the specified attribute is not in a particular enumerable object.
class Person < ActiveRecord::Base validates_exclusion_of :username, :in => %w( admin superuser ), :message => "You don't belong here" validates_exclusion_of :age, :in => 30..60, :message => "This site is only for under 30 and over 60" validates_exclusion_of :format, :in => %w( mov avi ), :message => "extension %s is not allowed" end
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 750 750: def validates_exclusion_of(*attr_names) 751: configuration = { :message => ActiveRecord::Errors.default_error_messages[:exclusion], :on => :save } 752: configuration.update(attr_names.extract_options!) 753: 754: enum = configuration[:in] || configuration[:within] 755: 756: raise(ArgumentError, "An object with the method include? is required must be supplied as the :in option of the configuration hash") unless enum.respond_to?("include?") 757: 758: validates_each(attr_names, configuration) do |record, attr_name, value| 759: record.errors.add(attr_name, configuration[:message] % value) if enum.include?(value) 760: end 761: end
Validates whether the value of the specified attribute is of the correct form by matching it against the regular expression provided.
class Person < ActiveRecord::Base validates_format_of :email, :with => /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/i, :on => :create end
Note: use \A and \Z to match the start and end of the string, ^ and $ match the start/end of a line.
A regular expression must be provided or else an exception will be raised.
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 688 688: def validates_format_of(*attr_names) 689: configuration = { :message => ActiveRecord::Errors.default_error_messages[:invalid], :on => :save, :with => nil } 690: configuration.update(attr_names.extract_options!) 691: 692: raise(ArgumentError, "A regular expression must be supplied as the :with option of the configuration hash") unless configuration[:with].is_a?(Regexp) 693: 694: validates_each(attr_names, configuration) do |record, attr_name, value| 695: record.errors.add(attr_name, configuration[:message] % value) unless value.to_s =~ configuration[:with] 696: end 697: end
Validates whether the value of the specified attribute is available in a particular enumerable object.
class Person < ActiveRecord::Base validates_inclusion_of :gender, :in => %w( m f ), :message => "woah! what are you then!??!!" validates_inclusion_of :age, :in => 0..99 validates_inclusion_of :format, :in => %w( jpg gif png ), :message => "extension %s is not included in the list" end
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 718 718: def validates_inclusion_of(*attr_names) 719: configuration = { :message => ActiveRecord::Errors.default_error_messages[:inclusion], :on => :save } 720: configuration.update(attr_names.extract_options!) 721: 722: enum = configuration[:in] || configuration[:within] 723: 724: raise(ArgumentError, "An object with the method include? is required must be supplied as the :in option of the configuration hash") unless enum.respond_to?("include?") 725: 726: validates_each(attr_names, configuration) do |record, attr_name, value| 727: record.errors.add(attr_name, configuration[:message] % value) unless enum.include?(value) 728: end 729: end
Validates that the specified attribute matches the length restrictions supplied. Only one option can be used at a time:
class Person < ActiveRecord::Base validates_length_of :first_name, :maximum=>30 validates_length_of :last_name, :maximum=>30, :message=>"less than %d if you don't mind" validates_length_of :fax, :in => 7..32, :allow_nil => true validates_length_of :phone, :in => 7..32, :allow_blank => true validates_length_of :user_name, :within => 6..20, :too_long => "pick a shorter name", :too_short => "pick a longer name" validates_length_of :fav_bra_size, :minimum=>1, :too_short=>"please enter at least %d character" validates_length_of :smurf_leader, :is=>4, :message=>"papa is spelled with %d characters... don't play me." end
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 507 507: def validates_length_of(*attrs) 508: # Merge given options with defaults. 509: options = { 510: :too_long => ActiveRecord::Errors.default_error_messages[:too_long], 511: :too_short => ActiveRecord::Errors.default_error_messages[:too_short], 512: :wrong_length => ActiveRecord::Errors.default_error_messages[:wrong_length] 513: }.merge(DEFAULT_VALIDATION_OPTIONS) 514: options.update(attrs.extract_options!.symbolize_keys) 515: 516: # Ensure that one and only one range option is specified. 517: range_options = ALL_RANGE_OPTIONS & options.keys 518: case range_options.size 519: when 0 520: raise ArgumentError, 'Range unspecified. Specify the :within, :maximum, :minimum, or :is option.' 521: when 1 522: # Valid number of options; do nothing. 523: else 524: raise ArgumentError, 'Too many range options specified. Choose only one.' 525: end 526: 527: # Get range option and value. 528: option = range_options.first 529: option_value = options[range_options.first] 530: 531: case option 532: when :within, :in 533: raise ArgumentError, ":#{option} must be a Range" unless option_value.is_a?(Range) 534: 535: too_short = options[:too_short] % option_value.begin 536: too_long = options[:too_long] % option_value.end 537: 538: validates_each(attrs, options) do |record, attr, value| 539: value = value.split(//) if value.kind_of?(String) 540: if value.nil? or value.size < option_value.begin 541: record.errors.add(attr, too_short) 542: elsif value.size > option_value.end 543: record.errors.add(attr, too_long) 544: end 545: end 546: when :is, :minimum, :maximum 547: raise ArgumentError, ":#{option} must be a nonnegative Integer" unless option_value.is_a?(Integer) and option_value >= 0 548: 549: # Declare different validations per option. 550: validity_checks = { :is => "==", :minimum => ">=", :maximum => "<=" } 551: message_options = { :is => :wrong_length, :minimum => :too_short, :maximum => :too_long } 552: 553: message = (options[:message] || options[message_options[option]]) % option_value 554: 555: validates_each(attrs, options) do |record, attr, value| 556: value = value.split(//) if value.kind_of?(String) 557: record.errors.add(attr, message) unless !value.nil? and value.size.method(validity_checks[option])[option_value] 558: end 559: end 560: end
Validates whether the value of the specified attribute is numeric by trying to convert it to a float with Kernel.Float (if only_integer is false) or applying it to the regular expression /\A[+\-]?\d+\Z/ (if only_integer is set to true).
class Person < ActiveRecord::Base validates_numericality_of :value, :on => :create end
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 830 830: def validates_numericality_of(*attr_names) 831: configuration = { :on => :save, :only_integer => false, :allow_nil => false } 832: configuration.update(attr_names.extract_options!) 833: 834: 835: numericality_options = ALL_NUMERICALITY_CHECKS.keys & configuration.keys 836: 837: (numericality_options - [ :odd, :even ]).each do |option| 838: raise ArgumentError, ":#{option} must be a number" unless configuration[option].is_a?(Numeric) 839: end 840: 841: validates_each(attr_names,configuration) do |record, attr_name, value| 842: raw_value = record.send("#{attr_name}_before_type_cast") || value 843: 844: next if configuration[:allow_nil] and raw_value.nil? 845: 846: if configuration[:only_integer] 847: unless raw_value.to_s =~ /\A[+-]?\d+\Z/ 848: record.errors.add(attr_name, configuration[:message] || ActiveRecord::Errors.default_error_messages[:not_a_number]) 849: next 850: end 851: raw_value = raw_value.to_i 852: else 853: begin 854: raw_value = Kernel.Float(raw_value.to_s) 855: rescue ArgumentError, TypeError 856: record.errors.add(attr_name, configuration[:message] || ActiveRecord::Errors.default_error_messages[:not_a_number]) 857: next 858: end 859: end 860: 861: numericality_options.each do |option| 862: case option 863: when :odd, :even 864: record.errors.add(attr_name, configuration[:message] || ActiveRecord::Errors.default_error_messages[option]) unless raw_value.to_i.method(ALL_NUMERICALITY_CHECKS[option])[] 865: else 866: message = configuration[:message] || ActiveRecord::Errors.default_error_messages[option] 867: message = message % configuration[option] if configuration[option] 868: record.errors.add(attr_name, message) unless raw_value.method(ALL_NUMERICALITY_CHECKS[option])[configuration[option]] 869: end 870: end 871: end 872: end
Validates that the specified attributes are not blank (as defined by Object#blank?). Happens by default on save. Example:
class Person < ActiveRecord::Base validates_presence_of :first_name end
The first_name attribute must be in the object and it cannot be blank.
If you want to validate the presence of a boolean field (where the real values are true and false), you will want to use validates_inclusion_of :field_name, :in => [true, false] This is due to the way Object#blank? handles boolean values. false.blank? # => true
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 464 464: def validates_presence_of(*attr_names) 465: configuration = { :message => ActiveRecord::Errors.default_error_messages[:blank], :on => :save } 466: configuration.update(attr_names.extract_options!) 467: 468: # can't use validates_each here, because it cannot cope with nonexistent attributes, 469: # while errors.add_on_empty can 470: send(validation_method(configuration[:on]), configuration) do |record| 471: record.errors.add_on_blank(attr_names, configuration[:message]) 472: end 473: end
Validates whether the value of the specified attributes are unique across the system. Useful for making sure that only one user can be named "davidhh".
class Person < ActiveRecord::Base validates_uniqueness_of :user_name, :scope => :account_id end
It can also validate whether the value of the specified attributes are unique based on multiple scope parameters. For example, making sure that a teacher can only be on the schedule once per semester for a particular class.
class TeacherSchedule < ActiveRecord::Base validates_uniqueness_of :teacher_id, :scope => [:semester_id, :class_id] end
When the record is created, a check is performed to make sure that no record exists in the database with the given value for the specified attribute (that maps to a column). When the record is updated, the same check is made but disregarding the record itself.
Because this check is performed outside the database there is still a chance that duplicate values will be inserted in two parallel transactions. To guarantee against this you should create a unique index on the field. See add_index for more information.
Configuration options:
# File vendor/rails/activerecord/lib/active_record/validations.rb, line 598 598: def validates_uniqueness_of(*attr_names) 599: configuration = { :message => ActiveRecord::Errors.default_error_messages[:taken], :case_sensitive => true } 600: configuration.update(attr_names.extract_options!) 601: 602: validates_each(attr_names,configuration) do |record, attr_name, value| 603: # The check for an existing value should be run from a class that 604: # isn't abstract. This means working down from the current class 605: # (self), to the first non-abstract class. Since classes don't know 606: # their subclasses, we have to build the hierarchy between self and 607: # the record's class. 608: class_hierarchy = [record.class] 609: while class_hierarchy.first != self 610: class_hierarchy.insert(0, class_hierarchy.first.superclass) 611: end 612: 613: # Now we can work our way down the tree to the first non-abstract 614: # class (which has a database table to query from). 615: finder_class = class_hierarchy.detect { |klass| !klass.abstract_class? } 616: 617: if value.nil? || (configuration[:case_sensitive] || !finder_class.columns_hash[attr_name.to_s].text?) 618: condition_sql = "#{record.class.quoted_table_name}.#{attr_name} #{attribute_condition(value)}" 619: condition_params = [value] 620: else 621: # sqlite has case sensitive SELECT query, while MySQL/Postgresql don't. 622: # Hence, this is needed only for sqlite. 623: condition_sql = "LOWER(#{record.class.quoted_table_name}.#{attr_name}) #{attribute_condition(value)}" 624: condition_params = [value.downcase] 625: end 626: 627: if scope = configuration[:scope] 628: Array(scope).map do |scope_item| 629: scope_value = record.send(scope_item) 630: condition_sql << " AND #{record.class.quoted_table_name}.#{scope_item} #{attribute_condition(scope_value)}" 631: condition_params << scope_value 632: end 633: end 634: 635: unless record.new_record? 636: condition_sql << " AND #{record.class.quoted_table_name}.#{record.class.primary_key} <> ?" 637: condition_params << record.send(:id) 638: end 639: 640: results = finder_class.with_exclusive_scope do 641: connection.select_all( 642: construct_finder_sql( 643: :select => "#{connection.quote_column_name(attr_name)}", 644: :from => "#{finder_class.quoted_table_name}", 645: :conditions => [condition_sql, *condition_params] 646: ) 647: ) 648: end 649: 650: unless results.length.zero? 651: found = true 652: 653: # As MySQL/Postgres don't have case sensitive SELECT queries, we try to find duplicate 654: # column in ruby when case sensitive option 655: if configuration[:case_sensitive] && finder_class.columns_hash[attr_name.to_s].text? 656: found = results.any? { |a| a[attr_name.to_s] == value } 657: end 658: 659: record.errors.add(attr_name, configuration[:message]) if found 660: end 661: end 662: end