NestedAttributesUniquenessValidator¶ ↑

• Source: github.com/joaomangilli/nested_attributes_uniqueness_validator

• Issues: github.com/joaomangilli/nested_attributes_uniqueness_validator/issues

Uniqueness validator for nested attributes. This gem solves the problem described in github.com/rails/rails/issues/4568.

# in Gemfile
gem 'nested_attributes_uniqueness_validator'

# Run bundler
$ bundle install

class Person < ActiveRecord::Base
  has_many :contacts

  validates :contacts, nested_attributes_uniqueness: { scope: [:person_id, :phone] }

  accepts_nested_attributes_for :contacts
end

class Contact < ActiveRecord::Base
  belongs_to :person
end

scope: Attributes that make up the scope of uniqueness. Required.
allow_destroyed: Consider records marked for destruction. Default: false.
allow_blank: Consider blank fields. Default: false.
attribute: Field that will receive the error message. Default: first attribute scope.
message: Error message. Default: taken.