Rails PayPal recurring monthly payment

payments_controller.rb

class PaymentsController < ActionController::Base

  skip_before_filter :verify_authenticity_token, :only => :notification

  before_filter :load_subscription

  def checkout
    redirect_to @subscription.paypal.checkout_url(
      return_url: "http://www.example.com" + "/paypal/review/#{@subscription.id}",
      cancel_url: "http://www.example.com" + "/paypal/cancel/#{@subscription.id}"
    )
  end

  def review
    @subscription.update_attributes(paypal_token: params["token"], paypal_payer_id: params["PayerID"])
  end

  def complete
    @subscription.paypal.make_recurring
  end

  def cancel
  end

  # Manage the paypal IPN
  #
  def notification
    notify = PaypalNotification.new(request.raw_post)
    if notify.acknowledge
      begin
        if notify.complete? && @subscription.amount == notify.amount
          # Mark as paid
        else
          # Mark as error and investigate
        end
      rescue => e
        # Mark as error and investigate
        raise
      end
    end

    render :nothing => true
  end

  private

    def load_subscription
      @subscription = Subscription.find(params[:id])
    end

end

paypal_payment.rb

class PaypalPayment
  def initialize(subscription)
    @subscription = subscription
  end
  
  def checkout_details
    process :checkout_details
  end
  
  def checkout_url(options)
    process(:checkout, options).checkout_url
  end
  
  def make_recurring
    payment = process(:request_payment)
    if payment.approved? && payment.completed?
      # Set the subscription as paid
    end
    recurring = process(:create_recurring_profile, {period: :monthly, frequency: 1, start_at: Time.zone.now + 30.days})
    @subscription.update_attribute(:paypal_profile_id, recurring.profile_id)
  end
  
  def cancel_recurring
    ppr = PayPal::Recurring.new(:profile_id => @subscription.paypal_profile_id)
    ppr.cancel
  end

private

  def process(action, options = {})
    options = options.reverse_merge(
      token: @subscription.paypal_token,
      payer_id: @subscription.paypal_payer_id,
      description: @subscription.name,
      amount: @subscription.amount,
      currency: "USD",
      ipn_url: "http://www.example.com" + "/paypal/notifications/#{@subscription.id}"
    )
    response = PayPal::Recurring.new(options).send(action)
    raise response.errors.inspect if response.errors.present?
    response
  end
end

subscription.rb

class Subscription < ActiveRecord::Base

  # Paypal specific fields
  #
  # t.string   "paypal_token"
  # t.string   "paypal_payer_id"
  # t.string   "paypal_profile_id"

  def paypal
    PaypalPayment.new(self)
  end

end