module ActiveRecord module SecureToken extend ActiveSupport::Concern module ClassMethods # Example using #has_secure_token # # # Schema: User(token:string, auth_token:string) # class User < ActiveRecord::Base # has_secure_token # has_secure_token :auth_token # end # # user = User.new # user.save # user.token # => "pX27zsMN2ViQKta1bGfLmVJE" # user.auth_token # => "77TMHrHJFvFDwodq8w7Ev2m7" # user.regenerate_token # => true # user.regenerate_auth_token # => true # # SecureRandom::base58 is used to generate the 24-character unique token, so collisions are highly unlikely. # # Note that it's still possible to generate a race condition in the database in the same way that # {validates_uniqueness_of}[rdoc-ref:Validations::ClassMethods#validates_uniqueness_of] can. # You're encouraged to add a unique index in the database to deal with this even more unlikely scenario. def has_secure_token(attribute = :token) # Load securerandom only when has_secure_token is used. require "active_support/core_ext/securerandom" define_method("regenerate_#{attribute}") { update! attribute => self.class.generate_unique_secure_token } before_create { self.send("#{attribute}=", self.class.generate_unique_secure_token) unless self.send("#{attribute}?") } end def generate_unique_secure_token SecureRandom.base58(24) end end end end