User Registration with Devise and Paypal

Question

I want to integrate Paypal within the Devise user registration process. What I want is to have a standard rails form based on the devise resource, that also has custom fields belonging to the user's model.

When a user fills in those fields and clicks on signup, it will be redirected to Paypal, when he clears from paypal and returns to our site then the user data must be created.

For the scenario where the user fill's out the paypal form but doesn't come back to our site, we have to keep record of user before redirecting to Paypal.

For this we can create a flag in user model and use Paypal IPN and when the user transaction notified, set that flag.

But in the case when the user is redirected to Paypal but doesn't complete the transaction, if the user returns to registration and signup again, our model should not throw error saying that the email entered already exists in the table.

How can we handle all these scenarios, is there any gem or plugin available to work with?

Answer 1

Here i am posting the detail code for performing the whole process.

registration_controller.rb

module Auth
  class RegistrationController < Devise::RegistrationsController
    include Auth::RegistrationHelper

    def create
      @user = User.new params[:user]
      if @user.valid?
        redirect_to get_subscribe_url(@user, request)
      else
        super
      end
    end
  end
end

registration_helper.rb

module Auth::RegistrationHelper
  def get_subscribe_url(user, request)
    url = Rails.env == "production" ? "https://www.paypal.com/cgi-bin/webscr/?" : "https://www.sandbox.paypal.com/cgi-bin/webscr/?"
    url + {
        :ip => request.remote_ip,
        :cmd => '_s-xclick',
        :hosted_button_id => (Rails.env == "production" ? "ID_FOR_BUTTON" : "ID_FOR_BUTTON"),
        :return_url => root_url,
        :cancel_return_url => root_url,
        :notify_url => payment_notifications_create_url,
        :allow_note => true,
        :custom => Base64.encode64("#{user.email}|#{user.organization_type_id}|#{user.password}")
    }.to_query
  end
end

payment_notification_controller.rb

class PaymentNotificationsController < ApplicationController
  protect_from_forgery :except => [:create]
  layout "single_column", :only => :show

  def create
    @notification = PaymentNotification.new
    @notification.transaction_id = params[:ipn_track_id]
    @notification.params = params
    @notification.status = "paid"
    @custom = Base64.decode64(params[:custom])
    @custom = @custom.split("|")
    @user = User.new
    @user.email = @custom[0]
    @user.organization_type_id = @custom[1].to_i
    @user.password = @custom[2]
    if @user.valid?
      @user.save
      @notification.user = @user
      @notification.save
      @user.send_confirmation_instructions
    end
    render :nothing => true
  end

  def show
  end
end