First pass at writing a signal handler to recharge transaction if account updated

payment/models.py

@@ -1,12 +1,17 @@
 from django.db import models
 from django.contrib.auth.models import User
 from django.conf import settings
+from django.db.models import Q
 
+import regluit.payment.manager
 from regluit.payment.parameters import *
 from regluit.payment.signals import credit_balance_added, pledge_created
 from regluit.utils.localdatetime import now
+
+from django.db.models.signals import post_save, post_delete
+
 from decimal import Decimal
-from datetime import timedelta
+import datetime 
 import uuid
 import urllib
 import logging
@@ -136,7 +141,7 @@ class Transaction(models.Model):
         self.approved=True
         now_val = now()
         self.date_authorized = now_val
-        self.date_expired = now_val + timedelta( days=settings.PREAPPROVAL_PERIOD )
+        self.date_expired = now_val + datetime.timedelta( days=settings.PREAPPROVAL_PERIOD )
         self.save()
         pledge_created.send(sender=self, transaction=self)
         
@@ -333,9 +338,6 @@ class Account(models.Model):
         self.date_deactivated = now()
         self.save()            
     
-from django.db.models.signals import post_save, post_delete
-import regluit.payment.manager
-
 # handle any save, updates to a payment.Transaction
 
 def handle_transaction_change(sender, instance, created, **kwargs):
@@ -355,3 +357,22 @@ def handle_transaction_delete(sender, instance, **kwargs):
 post_save.connect(handle_transaction_change,sender=Transaction)
 post_delete.connect(handle_transaction_delete,sender=Transaction)
 
+def recharge_failed_transactions(sender, created, instance, **kwargs):
+    """When a new Account is saved, check whether this is the new active account for a user.  If so, recharge any
+    outstanding failed transactions
+    """
+
+    transactions_to_recharge = instance.user.transaction_set.filter((Q(status=TRANSACTION_STATUS_FAILED) | Q(status=TRANSACTION_STATUS_ERROR)) & Q(campaign__status='UNSUCCESSFUL')).all()
+
+    if transactions_to_recharge:
+        pm = manager.PaymentManager()
+        for transaction in transactions_to_recharge:
+            # check whether we are still within the window to recharge
+            if (now() - transaction.campaign.deadline) < datetime.timedelta(settings.RECHARGE_WINDOW):
+                pm.execute_transaction(transaction)
+
+post_save.connect(recharge_failed_transactions, sender=Account)
+
+# handle recharging failed transactions
+
+

payment/parameters.py

@@ -48,3 +48,5 @@ TRANSACTION_STATUS_REFUNDED = 'Refunded'
 # The transaction was refused/denied
 TRANSACTION_STATUS_FAILED = 'Failed'
 
+# Transaction written off -- unable to successfully be charged after campaign succeeded 
+TRANSACTION_STATUS_WRITTEN_OFF = 'Written-Off'

settings/common.py

@@ -226,6 +226,9 @@ GLUEJAR_COMMISSION = 0.06
 PREAPPROVAL_PERIOD = 365 # days to ask for in a preapproval
 PREAPPROVAL_PERIOD_AFTER_CAMPAIGN = 90 # if we ask for preapproval time after a campaign deadline
 
+# How many days we will try to collect on failed transactions until they are written off
+RECHARGE_WINDOW = 7
+
 GOODREADS_API_KEY = ""
 GOODREADS_API_SECRET = ""