Normalizes a specified attribute using its declared normalizations.

Examples¶ ↑

class User
  include ActiveModel::Attributes
  include ActiveModel::Attributes::Normalization

  attribute :email, :string

  normalizes :email, with: -> email { email.strip.downcase }
end

legacy_user = User.load_from_legacy_data(...)
legacy_user.email # => " CRUISE-CONTROL@EXAMPLE.COM\n"
legacy_user.normalize_attribute(:email)
legacy_user.email # => "cruise-control@example.com"

Behavior with Active Record¶ ↑

To prevent confusion, normalization will not be applied when the attribute is fetched from the database. This means that if a record was persisted before the normalization was declared, the record’s attribute will not be normalized until either it is assigned a new value, or it is explicitly migrated via Normalization#normalize_attribute.

Be aware that if your app was created before Rails 7.1, and your app marshals instances of the targeted model (for example, when caching), then you should set ActiveRecord.marshalling_format_version to 7.1 or higher via either config.load_defaults 7.1 or config.active_record.marshalling_format_version = 7.1. Otherwise, Marshal may attempt to serialize the normalization Proc and raise TypeError.

class User < ActiveRecord::Base
  normalizes :email, with: -> email { email.strip.downcase }
  normalizes :phone, with: -> phone { phone.delete("^0-9").delete_prefix("1") }
end

user = User.create(email: " CRUISE-CONTROL@EXAMPLE.COM\n")
user.email                  # => "cruise-control@example.com"

user = User.find_by(email: "\tCRUISE-CONTROL@EXAMPLE.COM ")
user.email                  # => "cruise-control@example.com"
user.email_before_type_cast # => "cruise-control@example.com"

User.where(email: "\tCRUISE-CONTROL@EXAMPLE.COM ").count         # => 1
User.where(["email = ?", "\tCRUISE-CONTROL@EXAMPLE.COM "]).count # => 0

User.exists?(email: "\tCRUISE-CONTROL@EXAMPLE.COM ")         # => true
User.exists?(["email = ?", "\tCRUISE-CONTROL@EXAMPLE.COM "]) # => false

User.normalize_value_for(:phone, "+1 (555) 867-5309") # => "5558675309"