| Module | ActiveRecord::Validations::ClassMethods |
| In: |
vendor/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, :message => nil |
| DEFAULT_SIZE_VALIDATION_OPTIONS | = | DEFAULT_VALIDATION_OPTIONS.merge( :too_long => ActiveRecord::Errors.default_error_messages[:too_long], :too_short => ActiveRecord::Errors.default_error_messages[:too_short], :wrong_length => ActiveRecord::Errors.default_error_messages[:wrong_length] |
| ALL_RANGE_OPTIONS | = | [ :is, :within, :in, :minimum, :maximum ].freeze |
# File vendor/activerecord/lib/active_record/validations.rb, line 211
211: def validate(*methods, &block)
212: methods << block if block_given?
213: write_inheritable_set(:validate, methods)
214: end
# File vendor/activerecord/lib/active_record/validations.rb, line 216
216: def validate_on_create(*methods, &block)
217: methods << block if block_given?
218: write_inheritable_set(:validate_on_create, methods)
219: end
# File vendor/activerecord/lib/active_record/validations.rb, line 221
221: def validate_on_update(*methods, &block)
222: methods << block if block_given?
223: write_inheritable_set(:validate_on_update, methods)
224: 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
The terms_of_service attribute is entirely virtual. No database column is needed. This check is performed only if terms_of_service is not nil and by default on save.
Configuration options:
NOTE: The agreement is considered valid if it’s set to the string "1". This makes it easy to relate it to an HTML checkbox.
# File vendor/activerecord/lib/active_record/validations.rb, line 296
296: def validates_acceptance_of(*attr_names)
297: configuration = { :message => ActiveRecord::Errors.default_error_messages[:accepted], :on => :save }
298: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
299: configuration[:message].gsub!(/\"/, '\\\\\"')
300:
301: for attr_name in attr_names
302: attr_accessor(attr_name)
303: class_eval(%(#{validation_method(configuration[:on])} %{errors.add('#{attr_name}', "#{configuration[:message]}") unless #{attr_name}.nil? or #{attr_name} == "1"}))
304: end
305: end
Validates whether the associated object or objects are all themselves valid. 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. The Rails team recommends against this practice.
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 504
504: def validates_associated(*attr_names)
505: configuration = { :message => ActiveRecord::Errors.default_error_messages[:invalid], :on => :save }
506: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
507: configuration[:message].gsub!(/\"/, '\\\\\"')
508:
509: for attr_name in attr_names
510: class_eval(%(#{validation_method(configuration[:on])} %{
511: errors.add("#{attr_name}", "#{configuration[:message]}") unless
512: (#{attr_name}.is_a?(Array) ? #{attr_name} : [#{attr_name}]).inject(true){ |memo, record| (record.nil? or record.valid?) and memo }
513: }))
514: end
515: 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 person has to already have a password attribute (a column in the people table), but the password_confirmation is virtual. It exists only as an in-memory variable for validating the password. This check is performed only if password_confirmation is not nil and by default on save.
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 270
270: def validates_confirmation_of(*attr_names)
271: configuration = { :message => ActiveRecord::Errors.default_error_messages[:confirmation], :on => :save }
272: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
273: configuration[:message].gsub!(/\"/, '\\\\\"')
274:
275: for attr_name in attr_names
276: attr_accessor "#{attr_name}_confirmation"
277: class_eval(%(#{validation_method(configuration[:on])} %{errors.add('#{attr_name}', "#{configuration[:message]}") unless #{attr_name}_confirmation.nil? or #{attr_name} == #{attr_name}_confirmation}))
278: end
279: end
Validates each attribute against a block.
class Person < ActiveRecord::Base
validates_each :first_name, :last_name do |record, attr|
record.errors.add attr, 'starts with z.' if attr[0] == ?z
end
end
Options:
# File vendor/activerecord/lib/active_record/validations.rb, line 237
237: def validates_each(*attrs)
238: options = attrs.last.is_a?(Hash) ? attrs.pop.symbolize_keys : {}
239: attrs = attrs.flatten
240:
241: # Declare the validation.
242: send(validation_method(options[:on] || :save)) do |record|
243: attrs.each do |attr|
244: value = record.send(attr)
245: next if value.nil? && options[:allow_nil]
246: yield record, attr, value
247: end
248: end
249: 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 => /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/, :on => :create
end
A regular expression must be provided or else an exception will be raised.
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 441
441: def validates_format_of(*attr_names)
442: configuration = { :message => ActiveRecord::Errors.default_error_messages[:invalid], :on => :save, :with => nil }
443: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
444: configuration[:message].gsub!(/\"/, '\\\\\"')
445:
446: raise(ArgumentError, "A regular expression must be supplied as the :with option of the configuration hash") unless configuration[:with].is_a?(Regexp)
447:
448: for attr_name in attr_names
449: class_eval(%(#{validation_method(configuration[:on])} %{errors.add("#{attr_name}", "#{configuration[:message]}") unless #{attr_name} and #{attr_name}.to_s.match(/#{Regexp.quote(configuration[:with].source)}/)}))
450: end
451: 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
end
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 464
464: def validates_inclusion_of(*attr_names)
465: configuration = { :message => ActiveRecord::Errors.default_error_messages[:inclusion], :on => :save }
466: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
467: configuration[:message].gsub!(/\"/, '\\\\\"')
468:
469: enum = configuration[:in] || configuration[:within]
470: allow_nil = configuration[:allow_nil]
471:
472: 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?")
473:
474: for attr_name in attr_names
475: if allow_nil
476: class_eval(%(#{validation_method(configuration[:on])} %{errors.add("#{attr_name}", "#{configuration[:message]}") unless #{attr_name}.nil? or (#{enum.inspect}).include?(#{attr_name}) }))
477: else
478: class_eval(%(#{validation_method(configuration[:on])} %{errors.add("#{attr_name}", "#{configuration[:message]}") unless (#{enum.inspect}).include?(#{attr_name}) }))
479: end
480: end
481: 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 :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/activerecord/lib/active_record/validations.rb, line 346
346: def validates_length_of(*attrs)
347: # Merge given options with defaults.
348: options = DEFAULT_SIZE_VALIDATION_OPTIONS.dup
349: options.update(attrs.pop.symbolize_keys) if attrs.last.is_a?(Hash)
350:
351: # Ensure that one and only one range option is specified.
352: range_options = ALL_RANGE_OPTIONS & options.keys
353: case range_options.size
354: when 0
355: raise ArgumentError, 'Range unspecified. Specify the :within, :maximum, :minimum, or :is option.'
356: when 1
357: # Valid number of options; do nothing.
358: else
359: raise ArgumentError, 'Too many range options specified. Choose only one.'
360: end
361:
362: # Get range option and value.
363: option = range_options.first
364: option_value = options[range_options.first]
365:
366: # Declare different validations per option.
367: case range_options.first
368: when :within, :in
369: raise ArgumentError, ':within must be a Range' unless option_value.is_a?(Range)
370: validates_each(attrs, options) do |record, attr|
371: next if record.send(attr).nil? and options[:allow_nil]
372: record.errors.add_on_boundary_breaking(attr, option_value, options[:too_long], options[:too_short])
373: end
374: when :is
375: raise ArgumentError, ':is must be a nonnegative Integer' unless option_value.is_a?(Integer) and option_value >= 0
376: message = options[:message] || options[:wrong_length]
377: message = (message % option_value) rescue message
378: validates_each(attrs, options) do |record, attr, value|
379: record.errors.add(attr, message) if value.nil? or value.size != option_value
380: end
381: when :minimum
382: raise ArgumentError, ':minimum must be a nonnegative Integer' unless option_value.is_a?(Integer) and option_value >= 0
383: message = options[:message] || options[:too_short]
384: message = (message % option_value) rescue message
385: validates_each(attrs, options) do |record, attr, value|
386: record.errors.add(attr, message) if value.nil? or value.size < option_value
387: end
388: when :maximum
389: raise ArgumentError, ':maximum must be a nonnegative Integer' unless option_value.is_a?(Integer) and option_value >= 0
390: message = options[:message] || options[:too_long]
391: message = (message % option_value) rescue message
392: validates_each(attrs, options) do |record, attr, value|
393: record.errors.add(attr, message) if value.nil? or value.size > option_value
394: end
395: end
396: end
Validates whether the value of the specified attribute is numeric by trying to convert it to a float with Kernel.Float (if integer is false) or applying it to the regular expression /^[+\-]?\d+$/ (if integer is set to true).
class Person < ActiveRecord::Base
validates_numericality_of :value, :on => :create
end
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 529
529: def validates_numericality_of(*attr_names)
530: configuration = { :message => ActiveRecord::Errors.default_error_messages[:not_a_number], :on => :save,
531: :integer => false }
532: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
533:
534: for attr_name in attr_names
535: if configuration[:only_integer]
536: # we have to use a regexp here, because Kernel.Integer accepts nil and "0xdeadbeef", but does not
537: # accept "099" and String#to_i accepts everything. The string containing the regexp is evaluated twice
538: # so we have to escape everything properly
539: class_eval(%(#{validation_method(configuration[:on])} %{
540: errors.add("#{attr_name}", "#{configuration[:message]}") unless #{attr_name}_before_type_cast.to_s =~ /^[\\\\+\\\\-]?\\\\d+$/
541: }))
542: else
543: class_eval(%(#{validation_method(configuration[:on])} %{
544: begin
545: Kernel.Float(#{attr_name}_before_type_cast)
546: rescue ArgumentError, TypeError
547: errors.add("#{attr_name}", "#{configuration[:message]}")
548: end
549: }))
550: end
551: end
552: end
Validates that the specified attributes are neither nil nor empty. Happens by default on save.
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 312
312: def validates_presence_of(*attr_names)
313: configuration = { :message => ActiveRecord::Errors.default_error_messages[:empty], :on => :save }
314: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
315: configuration[:message].gsub!(/\"/, '\\\\\"')
316:
317: for attr_name in attr_names
318: class_eval(%(#{validation_method(configuration[:on])} %{errors.add_on_empty('#{attr_name}', "#{configuration[:message]}")}))
319: end
320: 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
When the record is created, a check is performed to make sure that no record exist 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.
Configuration options:
# File vendor/activerecord/lib/active_record/validations.rb, line 414
414: def validates_uniqueness_of(*attr_names)
415: configuration = { :message => ActiveRecord::Errors.default_error_messages[:taken] }
416: configuration.update(attr_names.pop) if attr_names.last.is_a?(Hash)
417: configuration[:message].gsub!(/\"/, '\\\\\"')
418:
419: for attr_name in attr_names
420: if scope = configuration[:scope]
421: class_eval(%(validate %{errors.add('#{attr_name}', "#{configuration[:message]}") if self.class.find_first(new_record? ? ['#{attr_name} = ? AND #{scope} = ?', #{attr_name}, #{scope}] : ["#{attr_name} = ? AND \\\#{self.class.primary_key} <> ? AND #{scope} = ?", #{attr_name}, id, #{scope}])}))
422: else
423: class_eval(%(validate %{errors.add('#{attr_name}', "#{configuration[:message]}") if self.class.find_first(new_record? ? ['#{attr_name} = ?', #{attr_name}] : ["#{attr_name} = ? AND \\\#{self.class.primary_key} <> ?", #{attr_name}, id])}))
424: end
425: end
426: end