PayPalExpressPayments.py

import urllib, md5, datetime
from cgi import parse_qs

class PayPal:
    """PayPal Utility Class
    * blog url
    * http://djangosnippets.org/snippets/1181/
    * https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_nvp_NVPAPIOverview
    """
    
    def __init__(self):
        ## Sandbox values
        self.signature_values = {
        'USER' : '', # Edit this to your API user name
        'PWD' : '', # Edit this to your API password
        'SIGNATURE' : '', # edit this to your API signature
        'VERSION' : '53.0',
        }
        self.return_url = "http://www.jgumbley.com/" 
        self.cancel_url = "http://www.jgumbley.com/" 
        self.API_ENDPOINT = 'https://api-3t.sandbox.paypal.com/nvp' # Sandbox URL, not production
        self.PAYPAL_URL = 'https://www.sandbox.paypal.com/webscr&cmd=_express-checkout&token='
        self.signature = urllib.urlencode(self.signature_values) + "&"

    # API METHODS
    
    ## Express Checkout:

    # Create Transaction - (add currency)
    def SetExpressCheckout(self, amount, **kwargs):
        params = {
            'METHOD' : "SetExpressCheckout",
            'NOSHIPPING' : 1,
            'PAYMENTACTION' : 'Authorization',
            'RETURNURL' : self.return_url,
            'CANCELURL' : self.cancel_url,
            'AMT' : amount,
        }
        params.update(kwargs)
        params_string = self.signature + urllib.urlencode(params)
        response = urllib.urlopen(self.API_ENDPOINT, params_string).read()
        response_dict = parse_qs(response)
        response_token = response_dict['TOKEN'][0]
        return response_token

    # Commit Express Checkout
    def DoExpressCheckoutPayment(self, token, payer_id, amt):
        params = {
            'METHOD' : "DoExpressCheckoutPayment",
            'PAYMENTACTION' : 'Sale',
            'RETURNURL' : 'http://www.yoursite.com/returnurl', #edit this 
            'CANCELURL' : 'http://www.yoursite.com/cancelurl', #edit this 
            'TOKEN' : token,
            'AMT' : amt,
            'PAYERID' : payer_id,
        }
        params_string = self.signature + urllib.urlencode(params)
        response = urllib.urlopen(self.API_ENDPOINT, params_string).read()
        response_tokens = {}
        for token in response.split('&'):
            response_tokens[token.split("=")[0]] = token.split("=")[1]
        for key in response_tokens.keys():
                response_tokens[key] = urllib.unquote(response_tokens[key])
        return response_tokens
        
              
import webbrowser
if __name__ == "__main__":
    pp = PayPal()
    # setup an express checkout token
    e_tk = pp.SetExpressCheckout(100)
    print "Token Recieved: " + e_tk
    url = pp.PAYPAL_URL + e_tk
    print "URL constructed: " + url
    webbrowser.open(url)
    print "Enter Payer_ID from URL query string when back from PayPal."
    pay_id = raw_input(">")
    print "Reponse from PayPal:"
    print pp.DoExpressCheckoutPayment(e_tk, pay_id, 100)