Module: ActiveRecord::Normalization::ClassMethods

Defined in:
lib/active_record/normalization.rb

Instance Method Summary collapse

Instance Method Details

#normalize_value_for(name, value) ⇒ Object

Normalizes a given value using normalizations declared for name.

Examples

class User < ActiveRecord::Base
  normalizes :email, with: -> email { email.strip.downcase }
end

User.normalize_value_for(:email, " [email protected]\n")
# => "[email protected]"



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# File 'lib/active_record/normalization.rb', line 106

def normalize_value_for(name, value)
  type_for_attribute(name).cast(value)
end

#normalizes(*names, with:, apply_to_nil: false) ⇒ Object

Declares a normalization for one or more attributes. The normalization is applied when the attribute is assigned or updated, and the normalized value will be persisted to the database. The normalization is also applied to the corresponding keyword argument of query methods. This allows a record to be created and later queried using unnormalized values.

However, to prevent confusion, the 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.

Because the normalization may be applied multiple times, it should be idempotent. In other words, applying the normalization more than once should have the same result as applying it only once.

By default, the normalization will not be applied to nil values. This behavior can be changed with the :apply_to_nil option.

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.

Options

  • :with - Any callable object that accepts the attribute’s value as its sole argument, and returns it normalized.

  • :apply_to_nil - Whether to apply the normalization to nil values. Defaults to false.

Examples

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: " [email protected]\n")
user.email                  # => "[email protected]"

user = User.find_by(email: "\[email protected] ")
user.email                  # => "[email protected]"
user.email_before_type_cast # => "[email protected]"

User.where(email: "\[email protected] ").count         # => 1
User.where(["email = ?", "\[email protected] "]).count # => 0

User.exists?(email: "\[email protected] ")         # => true
User.exists?(["email = ?", "\[email protected] "]) # => false

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



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# File 'lib/active_record/normalization.rb', line 88

def normalizes(*names, with:, apply_to_nil: false)
  decorate_attributes(names) do |name, cast_type|
    NormalizedValueType.new(cast_type: cast_type, normalizer: with, normalize_nil: apply_to_nil)
  end

  self.normalized_attributes += names.map(&:to_sym)
end