instance method `before_validation`

Ruby on Rails 4.1.16

Since v3.0.20

Available in: v3.0.20 v3.1.12 v3.2.22.5 v4.0.13 v4.1.16 v4.2.9 v5.2.8.1 v6.0.6 v6.1.7.10 v7.0.10 v7.1.6 v7.2.3 v8.0.4 v8.1.2

Compare with:

before_validation(*args, &block)

Defines a callback that will get called right before validation happens.

class Person
  include ActiveModel::Validations
  include ActiveModel::Validations::Callbacks

  attr_accessor :name

  validates_length_of :name, maximum: 6

  before_validation :remove_whitespaces

  private

  def remove_whitespaces
    name.strip!
  end
end

person = Person.new
person.name = '  bob  '
person.valid? # => true
person.name   # => "bob"

Parameters

args rest
block block

Source

# File activemodel/lib/active_model/validations/callbacks.rb, line 56
        def before_validation(*args, &block)
          options = args.last
          if options.is_a?(Hash) && options[:on]
            options[:if] = Array(options[:if])
            options[:on] = Array(options[:on])
            options[:if].unshift lambda { |o|
              options[:on].include? o.validation_context
            }
          end
          set_callback(:validation, :before, *args, &block)
        end

Defined in activemodel/lib/active_model/validations/callbacks.rb line 56 · View on GitHub · Improve this page · Find usages on GitHub

Defined in ActiveModel::Validations::Callbacks::ClassMethods

Signature

Parameters