unwrap_rails_4_session.rb

cj = ActionDispatch::Cookies::CookieJar.new(
  Rails.application.key_generator,
  Figaro.env.domain, # host
  false, # secure
  {
    signed_cookie_salt: Rails.application.config.action_dispatch.signed_cookie_salt,
    encrypted_cookie_salt: Rails.application.config.action_dispatch.encrypted_cookie_salt,
    encrypted_signed_cookie_salt: Rails.application.config.action_dispatch.encrypted_signed_cookie_salt,
    secret_key_base: Rails.application.config.secret_key_base,
    serializer: Rails.application.config.action_dispatch.cookies_serializer
  }
)

cj.update(cookie_hash)

cookie_hash.each_key {|k| puts "#{k}:"; p cj.encrypted[k] }