From 7ec1c726a6ca3c7e53098c5a53273f94810c6229 Mon Sep 17 00:00:00 2001
From: Tom Price <tom@codedinternet.com>
Date: Wed, 1 Mar 2017 02:42:39 +0000
Subject: [PATCH] Optimise down to just the one SQL query for waiting invoices.

Cuts down on all the unnecessary queries and selects everything in one go.
Down from ~6 queries per invoice
---
 RIGS/finance.py | 12 +++++++-----
 RIGS/models.py  |  8 +++++++-
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/RIGS/finance.py b/RIGS/finance.py
index f8d23f58..00786c62 100644
--- a/RIGS/finance.py
+++ b/RIGS/finance.py
@@ -1,6 +1,7 @@
 import cStringIO as StringIO
 import datetime
 import re
+from decimal import Decimal
 
 from django.contrib import messages
 from django.core.urlresolvers import reverse_lazy
@@ -31,12 +32,13 @@ class InvoiceIndex(generic.ListView):
 
     def get_queryset(self):
         query = self.model.objects.annotate(
-            cost=Sum(F('event__items__cost') * F('event__items__quantity'), output_field=FloatField()),
-            payment_count=Count('payment'),
-            payments=Sum('payment__amount'),
+            _sum_total=Sum(F('event__items__cost') * F('event__items__quantity'), output_field=FloatField()),
+            _payment_count=Count('payment'),
+            _payment_total=Sum('payment__amount'),
         ).filter(
-            Q(cost__gt=0.0, payment_count=0) | Q(cost__lt=Value('payments'), cost__gt=Value('payments'))
-        ).select_related('event', 'event__organisation', 'event__person', 'event__venue')
+            Q(_sum_total__gt=0.0, _payment_count=0) |
+            Q(_sum_total__lt=Value('_payment_total'), _sum_total__gt=Value('_payment_total'))
+        ).select_related('event', 'event__organisation', 'event__person', 'event__venue', 'event__mic')
 
         return query
 
diff --git a/RIGS/models.py b/RIGS/models.py
index 0650d81c..6aa16730 100644
--- a/RIGS/models.py
+++ b/RIGS/models.py
@@ -1,11 +1,11 @@
 import datetime
 import hashlib
-import pytz
 import random
 import string
 from collections import Counter
 from decimal import Decimal
 
+import pytz
 import reversion
 from django.conf import settings
 from django.contrib.auth.models import AbstractUser
@@ -509,6 +509,8 @@ class Invoice(models.Model):
 
     @property
     def sum_total(self):
+        if getattr(self, '_sum_total', None):
+            return Decimal(getattr(self, '_sum_total'))
         return self.event.sum_total
 
     @property
@@ -517,6 +519,10 @@ class Invoice(models.Model):
 
     @property
     def payment_total(self):
+        if hasattr(self, '_payment_total') and hasattr(self, '_payment_count'):
+            if getattr(self, '_payment_count') == 0:
+                return Decimal(0.00)
+            return Decimal(getattr(self, '_payment_total', 0.00))
         total = self.payment_set.aggregate(total=models.Sum('amount'))['total']
         if total:
             return total