Improves response time of sponsors page (#1948)

* Enable django's caching on sponsors list page

* Use inner join to also fetch for package and reduce query execution time

* Clean-up sponsors list cache after any sponsorship approval

* Cache sponsor page for only one day

* enable django caching via DB

Co-authored-by: Ee Durbin <[email protected]>
Co-authored-by: Ee Durbin <[email protected]>

Author: berinhard

pydotorg/settings/heroku.py

@@ -11,6 +11,15 @@
 DATABASE_CONN_MAX_AGE = 600
 DATABASES['default']['CONN_MAX_AGE'] = DATABASE_CONN_MAX_AGE
 
+## Django Caching
+
+CACHES = {
+    'default': {
+        'BACKEND': 'django.core.cache.backends.db.DatabaseCache',
+        'LOCATION': 'django_cache_table',
+    }
+}
+
 HAYSTACK_SEARCHBOX_SSL_URL = config(
     'SEARCHBOX_SSL_URL'
 )

sponsors/notifications.py

@@ -1,4 +1,5 @@
 from django.core.mail import EmailMessage
+from django.core.cache import cache
 from django.template.loader import render_to_string
 from django.conf import settings
 from django.contrib.admin.models import LogEntry, CHANGE, ADDITION
@@ -209,3 +210,9 @@ def notify(self, notification, sponsorship, contact_types, request, **kwargs):
             action_flag=CHANGE,
             change_message=msg
         )
+
+
+class RefreshSponsorshipsCache:
+    def notify(self, *args, **kwargs):
+        # clean up cached used by "sponsors/partials/sponsors-list.html"
+        cache.delete("CACHED_SPONSORS_LIST")

sponsors/templatetags/sponsors.py

@@ -1,5 +1,7 @@
 from collections import OrderedDict
 from django import template
+from django.conf import settings
+from django.core.cache import cache
 
 from ..models import Sponsorship, SponsorshipPackage, TieredQuantityConfiguration
 from sponsors.models.enums import PublisherChoices, LogoPlacementChoices
@@ -23,7 +25,7 @@ def full_sponsorship(sponsorship, display_fee=False):
 def list_sponsors(logo_place, publisher=PublisherChoices.FOUNDATION.value):
     sponsorships = Sponsorship.objects.enabled().with_logo_placement(
         logo_place=logo_place, publisher=publisher
-    ).order_by('package').select_related('sponsor')
+    ).order_by('package').select_related('sponsor', 'package')
     packages = SponsorshipPackage.objects.all()
 
     context = {
@@ -50,6 +52,7 @@ def list_sponsors(logo_place, publisher=PublisherChoices.FOUNDATION.value):
             'packages': SponsorshipPackage.objects.all(),
             'sponsorships_by_package': sponsorships_by_package,
         })
+
     return context
 
 

sponsors/tests/test_use_cases.py

@@ -187,10 +187,13 @@ def test_execute_and_update_database_object(self):
 
     def test_build_use_case_with_default_notificationss(self):
         uc = use_cases.ExecuteContractUseCase.build()
-        self.assertEqual(len(uc.notifications), 1)
+        self.assertEqual(len(uc.notifications), 2)
         self.assertIsInstance(
             uc.notifications[0], ExecutedContractLogger
         )
+        self.assertIsInstance(
+            uc.notifications[1], RefreshSponsorshipsCache,
+        )
 
 
 class ExecuteExistingContractUseCaseTests(TestCase):
@@ -219,10 +222,13 @@ def test_execute_and_update_database_object(self):
 
     def test_build_use_case_with_default_notificationss(self):
         uc = use_cases.ExecuteExistingContractUseCase.build()
-        self.assertEqual(len(uc.notifications), 1)
+        self.assertEqual(len(uc.notifications), 2)
         self.assertIsInstance(
             uc.notifications[0], ExecutedExistingContractLogger
         )
+        self.assertIsInstance(
+            uc.notifications[1], RefreshSponsorshipsCache,
+        )
 
 
 class NullifyContractUseCaseTests(TestCase):
@@ -239,10 +245,13 @@ def test_nullify_and_update_database_object(self):
 
     def test_build_use_case_with_default_notificationss(self):
         uc = use_cases.NullifyContractUseCase.build()
-        self.assertEqual(len(uc.notifications), 1)
+        self.assertEqual(len(uc.notifications), 2)
         self.assertIsInstance(
             uc.notifications[0], NullifiedContractLogger
         )
+        self.assertIsInstance(
+            uc.notifications[1], RefreshSponsorshipsCache,
+        )
 
 
 class SendSponsorshipNotificationUseCaseTests(TestCase):

sponsors/use_cases.py

@@ -94,6 +94,7 @@ def execute(self, contract, **kwargs):
 class ExecuteExistingContractUseCase(BaseUseCaseWithNotifications):
     notifications = [
         notifications.ExecutedExistingContractLogger(),
+        notifications.RefreshSponsorshipsCache(),
     ]
     force_execute = True
 
@@ -109,13 +110,15 @@ def execute(self, contract, contract_file, **kwargs):
 class ExecuteContractUseCase(ExecuteExistingContractUseCase):
     notifications = [
         notifications.ExecutedContractLogger(),
+        notifications.RefreshSponsorshipsCache(),
     ]
     force_execute = False
 
 
 class NullifyContractUseCase(BaseUseCaseWithNotifications):
     notifications = [
         notifications.NullifiedContractLogger(),
+        notifications.RefreshSponsorshipsCache(),
     ]
 
     def execute(self, contract, **kwargs):

templates/sponsors/partials/sponsors-list.html

@@ -1,4 +1,8 @@
 {% load thumbnail %}
+{% load cache %}
+
+{% comment %}cache for 1 day{% endcomment %}
+{% cache 86400 CACHED_SPONSORS_LIST %}
 
 {% if logo_place == "download" %}
   <h2 class="widget-title">Sponsors</h2>
@@ -51,3 +55,4 @@ <h1 style="font-size: {% if forloop.first %}350%{% else %}300%{% endif %}">{{ pa
   {% endif %}
   {% endfor %}
 {% endif %}
+{% endcache CACHED_SPONSORS_LIST %}