From 6122dcacc75163628a2544f6819d7623e93245d0 Mon Sep 17 00:00:00 2001
From: Jens Langhammer <jens.langhammer@beryju.org>
Date: Sun, 21 Jun 2020 12:40:01 +0200
Subject: [PATCH] flows: fix flow cache not being cleared correctly when stages
 are saved

---
 passbook/flows/apps.py    |  6 ++++++
 passbook/flows/signals.py | 31 +++++++++++++++++++++++++++++++
 passbook/policies/apps.py |  2 +-
 passbook/root/settings.py |  1 +
 4 files changed, 39 insertions(+), 1 deletion(-)
 create mode 100644 passbook/flows/signals.py

diff --git a/passbook/flows/apps.py b/passbook/flows/apps.py
index 11f2d21d4..f31f699da 100644
--- a/passbook/flows/apps.py
+++ b/passbook/flows/apps.py
@@ -1,4 +1,6 @@
 """passbook flows app config"""
+from importlib import import_module
+
 from django.apps import AppConfig
 
 
@@ -9,3 +11,7 @@ class PassbookFlowsConfig(AppConfig):
     label = "passbook_flows"
     mountpoint = "flows/"
     verbose_name = "passbook Flows"
+
+    def ready(self):
+        """Load policy cache clearing signals"""
+        import_module("passbook.flows.signals")
diff --git a/passbook/flows/signals.py b/passbook/flows/signals.py
new file mode 100644
index 000000000..d4353ef94
--- /dev/null
+++ b/passbook/flows/signals.py
@@ -0,0 +1,31 @@
+"""passbook flow signals"""
+from django.core.cache import cache
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+from structlog import get_logger
+
+LOGGER = get_logger()
+
+
+@receiver(post_save)
+# pylint: disable=unused-argument
+def invalidate_flow_cache(sender, instance, **_):
+    """Invalidate flow cache when flow is updated"""
+    from passbook.flows.models import Flow, FlowStageBinding, Stage
+    from passbook.flows.planner import cache_key
+
+    if isinstance(instance, Flow):
+        LOGGER.debug("Invalidating Flow cache", flow=instance)
+        cache.delete(f"{cache_key(instance)}*")
+    if isinstance(instance, FlowStageBinding):
+        LOGGER.debug("Invalidating Flow cache from FlowStageBinding", binding=instance)
+        cache.delete(f"{cache_key(instance.flow)}*")
+    if isinstance(instance, Stage):
+        LOGGER.debug("Invalidating Flow cache from Stage", stage=instance)
+        total = 0
+        for binding in FlowStageBinding.objects.filter(stage=instance):
+            prefix = cache_key(binding.flow)
+            keys = cache.keys(f"{prefix}*")
+            total += len(keys)
+            cache.delete_many(keys)
+        LOGGER.debug("Deleted keys", len=total)
diff --git a/passbook/policies/apps.py b/passbook/policies/apps.py
index 946f84609..f300fe6f3 100644
--- a/passbook/policies/apps.py
+++ b/passbook/policies/apps.py
@@ -12,5 +12,5 @@ class PassbookPoliciesConfig(AppConfig):
     verbose_name = "passbook Policies"
 
     def ready(self):
-        """Load source_types from config file"""
+        """Load policy cache clearing signals"""
         import_module("passbook.policies.signals")
diff --git a/passbook/root/settings.py b/passbook/root/settings.py
index 739edc462..43983c159 100644
--- a/passbook/root/settings.py
+++ b/passbook/root/settings.py
@@ -347,6 +347,7 @@ _LOGGING_HANDLER_MAP = {
     "passbook": LOG_LEVEL,
     "django": "WARNING",
     "celery": "WARNING",
+    "selenium": "WARNING",
     "grpc": LOG_LEVEL,
     "oauthlib": LOG_LEVEL,
     "oauth2_provider": LOG_LEVEL,