key_generator

# File railties/lib/rails/application.rb, line 172
    def key_generator
      # number of iterations selected based on consultation with the google security
      # team. Details at https://github.com/rails/rails/pull/6952#issuecomment-7661220
      @caching_key_generator ||=
        if secret_key_base
          ActiveSupport::CachingKeyGenerator.new(
            ActiveSupport::KeyGenerator.new(secret_key_base, iterations: 1000)
          )
        else
          ActiveSupport::LegacyKeyGenerator.new(secrets.secret_token)
        end
    end