gistfile1.rb

class PaymentsController < ApplicationController
  def new
    payment = order.payments.create!(amount: order.total)
    response = Payture.init options
    payment.update session_id: response[:session_id]
    redirect_to payment.payture_url
  end
end

class Payment < ActiveRecord::Base
  def payture_url
    "#{Payture.host}Pay?SessionId=#{self.session_id}"
  end
end

class NotificationsController < ApplicationController
  def create
    payment = Payment.find_by! session_id: params["SessionId"]
    payment.update(status: :paid) if params['Success'] == 'True'
  end
end