Make each item purchase transaction atomic

and add the ability to record the fulfillment time

lms/djangoapps/shoppingcart/migrations/0004_auto__add_field_orderitem_fulfilled_time.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding field 'OrderItem.fulfilled_time'
+        db.add_column('shoppingcart_orderitem', 'fulfilled_time',
+                      self.gf('django.db.models.fields.DateTimeField')(null=True),
+                      keep_default=False)
+
+
+    def backwards(self, orm):
+        # Deleting field 'OrderItem.fulfilled_time'
+        db.delete_column('shoppingcart_orderitem', 'fulfilled_time')
+
+
+    models = {
+        'auth.group': {
+            'Meta': {'object_name': 'Group'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '80'}),
+            'permissions': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Permission']", 'symmetrical': 'False', 'blank': 'True'})
+        },
+        'auth.permission': {
+            'Meta': {'ordering': "('content_type__app_label', 'content_type__model', 'codename')", 'unique_together': "(('content_type', 'codename'),)", 'object_name': 'Permission'},
+            'codename': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'content_type': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['contenttypes.ContentType']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '50'})
+        },
+        'auth.user': {
+            'Meta': {'object_name': 'User'},
+            'date_joined': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now'}),
+            'email': ('django.db.models.fields.EmailField', [], {'max_length': '75', 'blank': 'True'}),
+            'first_name': ('django.db.models.fields.CharField', [], {'max_length': '30', 'blank': 'True'}),
+            'groups': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Group']", 'symmetrical': 'False', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'is_active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'is_staff': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'is_superuser': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'last_login': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now'}),
+            'last_name': ('django.db.models.fields.CharField', [], {'max_length': '30', 'blank': 'True'}),
+            'password': ('django.db.models.fields.CharField', [], {'max_length': '128'}),
+            'user_permissions': ('django.db.models.fields.related.ManyToManyField', [], {'to': "orm['auth.Permission']", 'symmetrical': 'False', 'blank': 'True'}),
+            'username': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '30'})
+        },
+        'contenttypes.contenttype': {
+            'Meta': {'ordering': "('name',)", 'unique_together': "(('app_label', 'model'),)", 'object_name': 'ContentType', 'db_table': "'django_content_type'"},
+            'app_label': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'model': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'})
+        },
+        'shoppingcart.certificateitem': {
+            'Meta': {'object_name': 'CertificateItem', '_ormbases': ['shoppingcart.OrderItem']},
+            'course_enrollment': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['student.CourseEnrollment']"}),
+            'course_id': ('django.db.models.fields.CharField', [], {'max_length': '128', 'db_index': 'True'}),
+            'mode': ('django.db.models.fields.SlugField', [], {'max_length': '50'}),
+            'orderitem_ptr': ('django.db.models.fields.related.OneToOneField', [], {'to': "orm['shoppingcart.OrderItem']", 'unique': 'True', 'primary_key': 'True'})
+        },
+        'shoppingcart.order': {
+            'Meta': {'object_name': 'Order'},
+            'bill_to_cardtype': ('django.db.models.fields.CharField', [], {'max_length': '32', 'blank': 'True'}),
+            'bill_to_ccnum': ('django.db.models.fields.CharField', [], {'max_length': '8', 'blank': 'True'}),
+            'bill_to_city': ('django.db.models.fields.CharField', [], {'max_length': '64', 'blank': 'True'}),
+            'bill_to_country': ('django.db.models.fields.CharField', [], {'max_length': '64', 'blank': 'True'}),
+            'bill_to_first': ('django.db.models.fields.CharField', [], {'max_length': '64', 'blank': 'True'}),
+            'bill_to_last': ('django.db.models.fields.CharField', [], {'max_length': '64', 'blank': 'True'}),
+            'bill_to_postalcode': ('django.db.models.fields.CharField', [], {'max_length': '16', 'blank': 'True'}),
+            'bill_to_state': ('django.db.models.fields.CharField', [], {'max_length': '8', 'blank': 'True'}),
+            'bill_to_street1': ('django.db.models.fields.CharField', [], {'max_length': '128', 'blank': 'True'}),
+            'bill_to_street2': ('django.db.models.fields.CharField', [], {'max_length': '128', 'blank': 'True'}),
+            'currency': ('django.db.models.fields.CharField', [], {'default': "'usd'", 'max_length': '8'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'processor_reply_dump': ('django.db.models.fields.TextField', [], {'blank': 'True'}),
+            'purchase_time': ('django.db.models.fields.DateTimeField', [], {'null': 'True', 'blank': 'True'}),
+            'status': ('django.db.models.fields.CharField', [], {'default': "'cart'", 'max_length': '32'}),
+            'user': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['auth.User']"})
+        },
+        'shoppingcart.orderitem': {
+            'Meta': {'object_name': 'OrderItem'},
+            'currency': ('django.db.models.fields.CharField', [], {'default': "'usd'", 'max_length': '8'}),
+            'fulfilled_time': ('django.db.models.fields.DateTimeField', [], {'null': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'line_desc': ('django.db.models.fields.CharField', [], {'default': "'Misc. Item'", 'max_length': '1024'}),
+            'order': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['shoppingcart.Order']"}),
+            'qty': ('django.db.models.fields.IntegerField', [], {'default': '1'}),
+            'status': ('django.db.models.fields.CharField', [], {'default': "'cart'", 'max_length': '32'}),
+            'unit_cost': ('django.db.models.fields.DecimalField', [], {'default': '0.0', 'max_digits': '30', 'decimal_places': '2'}),
+            'user': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['auth.User']"})
+        },
+        'shoppingcart.paidcourseregistration': {
+            'Meta': {'object_name': 'PaidCourseRegistration', '_ormbases': ['shoppingcart.OrderItem']},
+            'course_id': ('django.db.models.fields.CharField', [], {'max_length': '128', 'db_index': 'True'}),
+            'mode': ('django.db.models.fields.SlugField', [], {'default': "'honor'", 'max_length': '50'}),
+            'orderitem_ptr': ('django.db.models.fields.related.OneToOneField', [], {'to': "orm['shoppingcart.OrderItem']", 'unique': 'True', 'primary_key': 'True'})
+        },
+        'student.courseenrollment': {
+            'Meta': {'ordering': "('user', 'course_id')", 'unique_together': "(('user', 'course_id'),)", 'object_name': 'CourseEnrollment'},
+            'course_id': ('django.db.models.fields.CharField', [], {'max_length': '255', 'db_index': 'True'}),
+            'created': ('django.db.models.fields.DateTimeField', [], {'auto_now_add': 'True', 'null': 'True', 'db_index': 'True', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'is_active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'mode': ('django.db.models.fields.CharField', [], {'default': "'honor'", 'max_length': '100'}),
+            'user': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['auth.User']"})
+        }
+    }
+
+    complete_apps = ['shoppingcart']
\ No newline at end of file

lms/djangoapps/shoppingcart/models.py

@@ -108,14 +108,14 @@ class Order(models.Model):
         self.bill_to_ccnum = ccnum
         self.bill_to_cardtype = cardtype
         self.processor_reply_dump = processor_reply_dump
+        # save these changes on the order, then we can tell when we are in an
+        # inconsistent state
         self.save()
         # this should return all of the objects with the correct types of the
         # subclasses
         orderitems = OrderItem.objects.filter(order=self).select_subclasses()
         for item in orderitems:
-            item.status = 'purchased'
-            item.save()
-            item.purchased_callback()
+            item.purchase_item()
 
 
 class OrderItem(models.Model):
@@ -136,6 +136,7 @@ class OrderItem(models.Model):
     unit_cost = models.DecimalField(default=0.0, decimal_places=2, max_digits=30)
     line_desc = models.CharField(default="Misc. Item", max_length=1024)
     currency = models.CharField(default="usd", max_length=8)  # lower case ISO currency codes
+    fulfilled_time = models.DateTimeField(null=True)
 
     @property
     def line_cost(self):
@@ -157,6 +158,17 @@ class OrderItem(models.Model):
         if order.currency != currency and order.orderitem_set.exists():
             raise InvalidCartItem(_("Trying to add a different currency into the cart"))
 
+    @transaction.commit_on_success
+    def purchase_item(self):
+        """
+        This is basically a wrapper around purchased_callback that handles
+        modifying the OrderItem itself
+        """
+        self.purchased_callback()
+        self.status = 'purchased'
+        self.fulfilled_time = datetime.now(pytz.utc)
+        self.save()
+
     def purchased_callback(self):
         """
         This is called on each inventory item in the shopping cart when the