From 07788d1de9b928b84e7e7ab040c9acdfd1ea80f4 Mon Sep 17 00:00:00 2001
From: xenua <git@xenua.me>
Date: Sun, 19 Jun 2022 17:34:10 +0200
Subject: [PATCH] implement cache invalidation

---
 leftists/apps.py    | 7 +++++++
 leftists/signals.py | 4 ++++
 2 files changed, 11 insertions(+)
 create mode 100644 leftists/signals.py

diff --git a/leftists/apps.py b/leftists/apps.py
index 7f1e36e..a17361a 100644
--- a/leftists/apps.py
+++ b/leftists/apps.py
@@ -1,6 +1,13 @@
 from django.apps import AppConfig
+from django.db.models.signals import pre_save
 
 
 class LeftistsConfig(AppConfig):
     default_auto_field = 'django.db.models.BigAutoField'
     name = 'leftists'
+
+    def ready(self):
+        from . import signals
+        from .models import ShortLink
+
+        pre_save.connect(signals.rmcache, sender=ShortLink)
diff --git a/leftists/signals.py b/leftists/signals.py
new file mode 100644
index 0000000..766a30b
--- /dev/null
+++ b/leftists/signals.py
@@ -0,0 +1,4 @@
+def rmcache(sender, **kwargs):
+    inst = kwargs.get("instance")
+    if inst.domain.fqdn in sender.cache:
+        del sender.cache[inst.domain.fqdn][inst.location]