Author: Özgür Vatansever <ozgurvt@gmail.com>

Pluggable paypal nvp (Name Value Pair) API implementation for django based web applications. The following image simply describes the express checkout flow (obtained from Express Checkout Integration Guide)

Installation

All you need to do is copying the "paypal" directory (or make a symbolink) under one of the directories in your PYTHON_PATH such as:

If you are using Python 2.5;

• /usr/local/lib/python2.5/site-packages/
• /usr/lib/python2.5/site-packages/

If you are using Python 2.6;

• /usr/local/lib/python2.6/dist-packages/
• /usr/lib/python2.6/dist-packages/

There are simply 4 main methods to be executed in order to finish the PayPal payment process.

Those are:

• SetExpressCheckout
• GetExpressCheckoutDetails (optional)
• DoExpressCheckoutPayment
• RefundTransaction (for refunds)
• DoDirectPayment (directly charge money from the credit card)

This package also includes 3 views that help you integrate PayPal checkout process to your application easily. Those views are;

• paypal.views.setcheckout
• paypal.views.docheckout
• paypal.views.dorefund

This package also includes 2 models that help you store actual PayPal API responses in your database. Those models are;

• paypal.models.PayPalResponse
• paypal.models.PayPalResponseStatus

You need to define your PayPal API Credientials in your projects settings file. Those are;

• PAYPAL_USER (api username)
• PAYPAL_PASSWORD (api password)
• PAYPAL_SIGNATURE (api signature)

Example

You have to have the following PayPal credientials for debugging and testing your app.

PAYPAL_USER  = "your paypal seller account"
PAYPAL_PASSWORD = "seller account password"
PAYPAL_SIGNATURE = "your api signature"
PAYPAL_DEBUG = True # for sandbox. False for real environment.

Once you copy the "paypal" directory under your PYTHON_PATH; you can enter shell by typing "python manage.py shell" command under your project root.

Then you can actually perform the following methods;

    In [1]: from paypal.driver import PayPal

    In [2]: p = PayPal()

    In [3]: p.SetExpressCheckout("10.00", "USD", "http://localhost/return", "http://localhost/cancel")

    - - - - - - - - - - 
    You can see the error that the server sends by calling
    - p.apierror

    Also, you can see the full response that comes from the PayPal server by calling
    - p.api_response

    when you are in python shell.
    - - - - - - - - - - 
    
    In [4]: p.DoExpressCheckoutPayment("USD", "10.00", "token", "payerid")
    
Also you can refund money;

   In [5]: p.RefundTransaction(transid = "transactionid", refundtype = "Partial", currency = "USD", amount = "10.00")

You can persist the results to your database. This package includes two DB models;

• PayPalResponse (responsible for storing API responses)
• PayPalResponseStatus (can be "Sale" or "Refund")

   p = PayPal()
   result = p.DoExpressCheckoutPayment("USD", "10.00", "token", "payerid")
   if result == True:
       response = PayPalResponse()
       response.fill_from_response(p.GetPaymentResponse())
       response.status = PayPalResponse.get_default_status()
       response.save()

You can also do this for refunds:

   p = PayPal()
   result = p.RefundTransaction("transid", "Partial", "USD", "10.00")
   if result == True:
       response = PayPalResponse()
       response.fill_from_response(p.GetRefundResponse(), action = "Refund")
       response.status = PayPalResponse.get_cancel_status()
       response.save()

You can directly charge money from the customer's credit card by simply performing DoDirectPayment method.

    p.DoDirectPayment("5475216669208487", "062015", "487", "MasterCard", "Ozgur", "Vatansever", Decimal(1), ipaddress = "127.0.0.1", street="my street", city = "istanbul", state="marmara", countrycode="TR", zip="34347")

TEST APPLICATION

I've just implemented a simple test application to show how to use PayPal Django Driver in your django applications. After you check out the source code, enter the directory "testapp" and run the application.