class ActiveSupport::KeyGenerator

def initialize(secret, options = {})
  @secret = secret
  # The default iterations are higher than required for our key derivation uses
  # on the off chance someone uses this for password storage
  @iterations = options[:iterations] || 2**16
  # Also allow configuration here so people can use this to build a rotation
  # scheme when switching the digest class.
  @hash_digest_class = options[:hash_digest_class] || self.class.hash_digest_class
end