Class: ActiveRecord::Validations::UniquenessValidator

Inherits:
ActiveModel::EachValidator
  • Object
show all
Defined in:
lib/active_record/validations/uniqueness.rb

Overview

:nodoc:

Instance Method Summary collapse

Constructor Details

#initialize(options) ⇒ UniquenessValidator

Returns a new instance of UniquenessValidator.



6
7
8
9
10
11
12
13
14
15
16
17
18
 
# File 'lib/active_record/validations/uniqueness.rb', line 6

def initialize(options)
  if options[:conditions] && !options[:conditions].respond_to?(:call)
    raise ArgumentError, "#{options[:conditions]} was passed as :conditions but is not callable. " \
                         "Pass a callable instead: `conditions: -> { where(approved: true) }`"
  end
  unless Array(options[:scope]).all? { |scope| scope.respond_to?(:to_sym) }
    raise ArgumentError, "#{options[:scope]} is not supported format for :scope option. " \
      "Pass a symbol or an array of symbols instead: `scope: :user_id`"
  end
  super
  @klass = options[:class]
  @klass = @klass.superclass if @klass.singleton_class?
end

Instance Method Details

#validate_each(record, attribute, value) ⇒ Object 



20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
 
# File 'lib/active_record/validations/uniqueness.rb', line 20

def validate_each(record, attribute, value)
  finder_class = find_finder_class_for(record)
  value = map_enum_attribute(finder_class, attribute, value)

  return if record.persisted? && !validation_needed?(finder_class, record, attribute)

  relation = build_relation(finder_class, attribute, value)
  if record.persisted?
    if finder_class.primary_key
      relation = relation.where.not(finder_class.primary_key => [record.id_in_database])
    else
      raise UnknownPrimaryKey.new(finder_class, "Cannot validate uniqueness for persisted record without primary key.")
    end
  end
  relation = scope_relation(record, relation)

  if options[:conditions]
    conditions = options[:conditions]

    relation = if conditions.arity.zero?
      relation.instance_exec(&conditions)
    else
      relation.instance_exec(record, &conditions)
    end
  end

  if relation.exists?
    error_options = options.except(:case_sensitive, :scope, :conditions)
    error_options[:value] = value

    record.errors.add(attribute, :taken, **error_options)
  end
end