src/paypal/rest.py

   1 # This file is part of Wolne Lektury, licensed under GNU Affero GPLv3 or later.
   2 # Copyright © Fundacja Wolne Lektury. See NOTICE for more information.
   3 #
   4 from datetime import date, datetime, timedelta
   5 from decimal import Decimal
   6 import paypalrestsdk
   7 from django.contrib.sites.models import Site
   8 from django.urls import reverse
   9 from django.utils import timezone
  10 from django.conf import settings
  11 from .models import BillingPlan, BillingAgreement
  12
  13 paypalrestsdk.configure(settings.PAYPAL_CONFIG)
  14
  15
  16 class PaypalError(Exception):
  17     pass
  18
  19
  20 def absolute_url(url_name, kwargs=None):
  21     return "http://%s%s" % (Site.objects.get_current().domain, reverse(url_name, kwargs=kwargs))
  22
  23
  24 def create_plan(amount):
  25     billing_plan = paypalrestsdk.BillingPlan({
  26         "name": "Cykliczna darowizna na Wolne Lektury: %s zł" % amount,
  27         "description": "Cykliczna darowizna na wsparcie Wolnych Lektur",
  28         "merchant_preferences": {
  29             "auto_bill_amount": "yes",
  30             "return_url": absolute_url('paypal_return', {'key': '-'}),
  31             "cancel_url": absolute_url('paypal_cancel'),
  32             # "initial_fail_amount_action": "continue",
  33             "max_fail_attempts": "3",
  34         },
  35         "payment_definitions": [
  36             {
  37                 "amount": {
  38                     "currency": "PLN",
  39                     "value": str(amount),
  40                 },
  41                 "cycles": "0",
  42                 "frequency": "MONTH",
  43                 "frequency_interval": "1",
  44                 "name": "Cykliczna darowizna",
  45                 "type": "REGULAR",
  46             }
  47         ],
  48         "type": "INFINITE",
  49     })
  50
  51     if not billing_plan.create():
  52         raise PaypalError(billing_plan.error)
  53     if not billing_plan.activate():
  54         raise PaypalError(billing_plan.error)
  55     plan, created = BillingPlan.objects.get_or_create(amount=amount, defaults={'plan_id': billing_plan.id})
  56     return plan.plan_id
  57
  58
  59 def get_link(links, rel):
  60     for link in links:
  61         if link.rel == rel:
  62             return link.href
  63
  64
  65 def create_agreement(amount, key, app=False):
  66     try:
  67         plan = BillingPlan.objects.get(amount=amount)
  68     except BillingPlan.DoesNotExist:
  69         plan_id = create_plan(amount)
  70     else:
  71         plan_id = plan.plan_id
  72     start = (timezone.now() + timedelta(0, 3600*24)).astimezone(timezone.utc).strftime('%Y-%m-%dT%H:%M:%SZ')
  73     billing_agreement = paypalrestsdk.BillingAgreement({
  74         "name": "Subskrypcja klubu WL",
  75         "description": "Stałe wsparcie Wolnych Lektur kwotą %s złotych" % amount,
  76         "start_date": start,
  77         "plan": {
  78             "id": plan_id,
  79         },
  80         "payer": {
  81             "payment_method": "paypal"
  82         },
  83     })
  84     if app:
  85         billing_agreement['override_merchant_preferences'] = {
  86             'return_url': absolute_url('paypal_app_return', {'key': key}),
  87         }
  88     else:
  89         billing_agreement['override_merchant_preferences'] = {
  90             'return_url': absolute_url('paypal_return', {'key': key}),
  91         }
  92
  93
  94     response = billing_agreement.create()
  95     if response:
  96         return billing_agreement
  97     else:
  98         raise PaypalError(billing_agreement.error)
  99
 100
 101 def agreement_approval_url(amount, key, app=False):
 102     agreement = create_agreement(amount, key, app=app)
 103     return get_link(agreement.links, 'approval_url')
 104
 105
 106 def get_agreement(agreement_id):
 107     try:
 108         return paypalrestsdk.BillingAgreement.find(agreement_id)
 109     except paypalrestsdk.ResourceNotFound:
 110         return None
 111
 112
 113 def check_agreement(agreement_id):
 114     a = get_agreement(agreement_id)
 115     if a:
 116         return a.state == 'Active'
 117
 118
 119 def execute_agreement(token):
 120     return paypalrestsdk.BillingAgreement.execute(token)
 121
 122
 123 def get_donations(agreement_id, year):
 124     a = get_agreement(agreement_id)
 125     transactions = []
 126     for transaction in a.search_transactions(
 127             date(year - 1, 12, 31),
 128             date(year + 1, 1, 1))['agreement_transaction_list']:
 129         if transaction['status'] != 'Completed':
 130             continue
 131         dt = datetime.strptime(
 132             transaction['time_stamp'],
 133             '%Y-%m-%dT%H:%M:%S%z'
 134         ).astimezone()
 135         if dt.year != year:
 136             continue
 137         assert transaction['amount']['currency'] == 'PLN'
 138         transactions.append({
 139             'timestamp': dt,
 140             'amount': Decimal(transaction['amount']['value'])
 141         })
 142     return transactions