class ActiveRecord::Type::Integer

Active Model Integer Type¶ ↑

Attribute type for integer representation. This type is registered under the :integer key.

class Person
  include ActiveModel::Attributes

  attribute :age, :integer
end

Values are cast using their to_i method, except for blank strings, which are cast to nil. If a to_i method is not defined or raises an error, the value will be cast to nil.

person = Person.new

person.age = "18"
person.age # => 18

person.age = ""
person.age # => nil

person.age = :not_an_integer
person.age # => nil (because Symbol does not define #to_i)

Serialization also works under the same principle. Non-numeric strings are serialized as nil, for example.

Serialization also validates that the integer can be stored using a limited number of bytes. If it cannot, an ActiveModel::RangeError will be raised. The default limit is 4 bytes, and can be customized when declaring an attribute:

class Person
  include ActiveModel::Attributes

  attribute :age, :integer, limit: 6
end

# File activemodel/lib/active_model/type/integer.rb, line 51
def initialize(**)
  super
  @range = min_value...max_value
end

# File activemodel/lib/active_model/type/integer.rb, line 60
def deserialize(value)
  return if value.blank?
  value.to_i
end

# File activemodel/lib/active_model/type/integer.rb, line 74
def serializable?(value)
  cast_value = cast(value)
  in_range?(cast_value) || begin
    yield cast_value if block_given?
    false
  end
end

# File activemodel/lib/active_model/type/integer.rb, line 65
def serialize(value)
  return if value.is_a?(::String) && non_numeric_string?(value)
  ensure_in_range(super)
end

# File activemodel/lib/active_model/type/integer.rb, line 56
def type
  :integer
end