From 19b95c2dc6bd0caad95f01eb50732b1702a4a71b Mon Sep 17 00:00:00 2001
From: Wilhelm Behncke <wilhelm.behncke@protonmail.com>
Date: Fri, 21 Jun 2024 18:51:29 +0200
Subject: [PATCH] BUGFIX: Flush content cache on discard all

This is achieved via a catch up hook for the workspace projection that
utilized info from the PendingChangesProjection to figure out which
nodes need to be considered for cache invalidation.
---
 ...ceProjectorCatchUpHookForCacheFlushing.php | 64 +++++++++++++++++++
 ...ctorCatchUpHookForCacheFlushingFactory.php | 32 ++++++++++
 .../Settings.ContentRepositoryRegistry.yaml   |  4 ++
 3 files changed, 100 insertions(+)
 create mode 100644 Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushing.php
 create mode 100644 Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushingFactory.php

diff --git a/Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushing.php b/Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushing.php
new file mode 100644
index 00000000000..00ac11cb9bd
--- /dev/null
+++ b/Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushing.php
@@ -0,0 +1,64 @@
+<?php
+
+namespace Neos\Neos\Fusion\Cache;
+
+/*
+ * This file is part of the Neos.Neos package.
+ *
+ * (c) Contributors of the Neos Project - www.neos.io
+ *
+ * This package is Open Source Software. For the full copyright and license
+ * information, please view the LICENSE file which was distributed with this
+ * source code.
+ */
+
+use Neos\ContentRepository\Core\ContentRepository;
+use Neos\ContentRepository\Core\EventStore\EventInterface;
+use Neos\ContentRepository\Core\Feature\WorkspacePublication\Event\WorkspaceWasDiscarded;
+use Neos\ContentRepository\Core\Projection\CatchUpHookInterface;
+use Neos\EventStore\Model\EventEnvelope;
+use Neos\Neos\PendingChangesProjection\ChangeFinder;
+
+/**
+ * @internal
+ */
+class WorkspaceProjectorCatchUpHookForCacheFlushing implements CatchUpHookInterface
+{
+    public function __construct(
+        private readonly ContentRepository $contentRepository,
+        private readonly ContentCacheFlusher $contentCacheFlusher
+    ) {
+    }
+
+    public function onBeforeCatchUp(): void
+    {
+    }
+
+    public function onBeforeEvent(EventInterface $eventInstance, EventEnvelope $eventEnvelope): void
+    {
+        if ($eventInstance instanceof WorkspaceWasDiscarded) {
+            $changeFinder = $this->contentRepository->projectionState(ChangeFinder::class);
+            $changes = $changeFinder->findByContentStreamId($eventInstance->previousContentStreamId);
+
+            foreach ($changes as $change) {
+                $this->contentCacheFlusher->flushNodeAggregate(
+                    $this->contentRepository,
+                    $eventInstance->workspaceName,
+                    $change->nodeAggregateId
+                );
+            }
+        }
+    }
+
+    public function onAfterEvent(EventInterface $eventInstance, EventEnvelope $eventEnvelope): void
+    {
+    }
+
+    public function onBeforeBatchCompleted(): void
+    {
+    }
+
+    public function onAfterCatchUp(): void
+    {
+    }
+}
diff --git a/Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushingFactory.php b/Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushingFactory.php
new file mode 100644
index 00000000000..0060cfe57f9
--- /dev/null
+++ b/Neos.Neos/Classes/Fusion/Cache/WorkspaceProjectorCatchUpHookForCacheFlushingFactory.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace Neos\Neos\Fusion\Cache;
+
+/*
+ * This file is part of the Neos.Neos package.
+ *
+ * (c) Contributors of the Neos Project - www.neos.io
+ *
+ * This package is Open Source Software. For the full copyright and license
+ * information, please view the LICENSE file which was distributed with this
+ * source code.
+ */
+
+use Neos\ContentRepository\Core\ContentRepository;
+use Neos\ContentRepository\Core\Projection\CatchUpHookFactoryInterface;
+
+class WorkspaceProjectorCatchUpHookForCacheFlushingFactory implements CatchUpHookFactoryInterface
+{
+    public function __construct(
+        private readonly ContentCacheFlusher $contentCacheFlusher
+    ) {
+    }
+
+    public function build(ContentRepository $contentRepository): WorkspaceProjectorCatchUpHookForCacheFlushing
+    {
+        return new WorkspaceProjectorCatchUpHookForCacheFlushing(
+            $contentRepository,
+            $this->contentCacheFlusher
+        );
+    }
+}
diff --git a/Neos.Neos/Configuration/Settings.ContentRepositoryRegistry.yaml b/Neos.Neos/Configuration/Settings.ContentRepositoryRegistry.yaml
index fe26202594d..68479d6a054 100644
--- a/Neos.Neos/Configuration/Settings.ContentRepositoryRegistry.yaml
+++ b/Neos.Neos/Configuration/Settings.ContentRepositoryRegistry.yaml
@@ -19,5 +19,9 @@ Neos:
             catchUpHooks:
               'Neos.Neos:FlushContentCache':
                 factoryObjectName: Neos\Neos\Fusion\Cache\GraphProjectorCatchUpHookForCacheFlushingFactory
+          'Neos.ContentRepository:Workspace':
+            catchUpHooks:
+              'Neos.Neos:FlushContentCache':
+                factoryObjectName: Neos\Neos\Fusion\Cache\WorkspaceProjectorCatchUpHookForCacheFlushingFactory
           'Neos.Neos:AssetUsage':
             factoryObjectName: Neos\Neos\AssetUsage\Projection\AssetUsageProjectionFactory