From b1e8b3308511857dad488af6d169523c0de90c87 Mon Sep 17 00:00:00 2001
From: Adam Vessey <adam@discoverygarden.ca>
Date: Mon, 25 Mar 2024 13:32:12 -0300
Subject: [PATCH] Theorhetical, better caching.

---
 embargo.services.yml                          |  7 ++
 src/Cache/Context/IpRangeCacheContext.php     | 81 +++++++++++++++++++
 src/Entity/Embargo.php                        | 34 +++++---
 src/Entity/IpRange.php                        | 10 +++
 .../search_api/processor/EmbargoProcessor.php |  2 +-
 5 files changed, 124 insertions(+), 10 deletions(-)
 create mode 100644 src/Cache/Context/IpRangeCacheContext.php

diff --git a/embargo.services.yml b/embargo.services.yml
index b316143..a7470c3 100644
--- a/embargo.services.yml
+++ b/embargo.services.yml
@@ -38,3 +38,10 @@ services:
       - '@service_container'
     tags:
       - { name: 'event_subscriber' }
+  cache_context.ip.embargo_range:
+    class: Drupal\embargo\Cache\Context\IpRangeCacheContext
+    arguments:
+      - '@request_stack'
+      - '@entity_type.manager'
+    tags:
+      - { name: cache.context }
diff --git a/src/Cache/Context/IpRangeCacheContext.php b/src/Cache/Context/IpRangeCacheContext.php
new file mode 100644
index 0000000..8f77b17
--- /dev/null
+++ b/src/Cache/Context/IpRangeCacheContext.php
@@ -0,0 +1,81 @@
+<?php
+
+namespace Drupal\embargo\Cache\Context;
+
+use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Cache\Context\CacheContextInterface;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+/**
+ * Applicable embargo IP range cache context info.
+ */
+class IpRangeCacheContext implements CacheContextInterface {
+
+  /**
+   * Memoized ranges.
+   *
+   * @var \Drupal\embargo\IpRangeInterface[]
+   */
+  protected array $ranges;
+
+  /**
+   * Constructor.
+   */
+  public function __construct(
+    protected RequestStack $requestStack,
+    protected EntityTypeManagerInterface $entityTypeManager,
+  ) {
+    // No-op, other than stashing properties.
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function getLabel() {
+    return \t('Embargo, Applicable IP Ranges');
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function getContext() {
+    $range_keys = array_keys($this->getRanges());
+    sort($range_keys, SORT_NUMERIC);
+    return implode(',', $range_keys);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public function getCacheableMetadata() {
+    $cache_meta = new CacheableMetadata();
+
+    foreach ($this->getRanges() as $range) {
+      $cache_meta->addCacheableDependency($range);
+    }
+
+    return $cache_meta;
+  }
+
+  /**
+   * Get any IP range entities associated with the current IP address.
+   *
+   * @return \Drupal\embargo\IpRangeInterface[]
+   *   Any relevant IP range entities.
+   *
+   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
+   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
+   */
+  protected function getRanges() : array {
+    if (!isset($this->ranges)) {
+      /** @var \Drupal\embargo\IpRangeStorageInterface $embargo_ip_range_storage */
+      $embargo_ip_range_storage = $this->entityTypeManager->getStorage('embargo_ip_range');
+      $this->ranges = $embargo_ip_range_storage->getApplicableIpRanges($this->requestStack->getCurrentRequest()
+        ->getClientIp());
+    }
+
+    return $this->ranges;
+  }
+
+}
diff --git a/src/Entity/Embargo.php b/src/Entity/Embargo.php
index 03f8b57..1201540 100644
--- a/src/Entity/Embargo.php
+++ b/src/Entity/Embargo.php
@@ -378,33 +378,49 @@ public function setEmbargoedNode(NodeInterface $node): EmbargoInterface {
   }
 
   /**
-   * The maximum age for which this object may be cached.
-   *
-   * @return int
-   *   The maximum time in seconds that this object may be cached.
+   * {@inheritDoc}
    */
   public function getCacheMaxAge() {
+    $max_age = parent::getCacheMaxAge();
+
     $now = time();
     // Invalidate cache after a scheduled embargo expires.
     if ($this->getExpirationType() === static::EXPIRATION_TYPE_SCHEDULED && !$this->expiresBefore($now)) {
-      return $this->getExpirationDate()->getTimestamp() - $now;
+      $max_age = Cache::mergeMaxAges($max_age, $this->getExpirationDate()->getTimestamp() - $now);
     }
-    // Other properties of the embargo are not time dependent.
-    return parent::getCacheMaxAge();
+
+    return $max_age;
   }
 
   /**
    * {@inheritdoc}
    */
   public function getCacheTags() {
-    $tags = parent::getCacheTags();
-    $tags[] = "node:{$this->getEmbargoedNode()->id()}";
+    $tags = Cache::mergeTags(parent::getCacheTags(), $this->getEmbargoedNode()->getCacheTags());
+
     if ($this->getExemptIps()) {
       $tags = Cache::mergeTags($tags, $this->getExemptIps()->getCacheTags());
     }
     return $tags;
   }
 
+  /**
+   * {@inheritDoc}
+   */
+  public function getCacheContexts() {
+    $contexts = Cache::mergeContexts(
+      parent::getCacheContexts(),
+      $this->getEmbargoedNode()->getCacheContexts(),
+      [$this->getExemptUsers() ? 'user' : 'user.permissions'],
+    );
+
+    if ($this->getExemptIps()) {
+      $contexts = Cache::mergeContexts($contexts, $this->getExemptIps()->getCacheContexts());
+    }
+
+    return $contexts;
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/src/Entity/IpRange.php b/src/Entity/IpRange.php
index 60bea11..1590688 100644
--- a/src/Entity/IpRange.php
+++ b/src/Entity/IpRange.php
@@ -3,6 +3,7 @@
 namespace Drupal\embargo\Entity;
 
 use Drupal\Component\Utility\UrlHelper;
+use Drupal\Core\Cache\Cache;
 use Drupal\Core\Entity\ContentEntityBase;
 use Drupal\Core\Entity\EntityStorageException;
 use Drupal\Core\Entity\EntityStorageInterface;
@@ -239,4 +240,13 @@ public static function isValidCidr(string $cidr): bool {
     return FALSE;
   }
 
+  /**
+   * {@inheritDoc}
+   */
+  public function getCacheContexts() {
+    return Cache::mergeContexts(parent::getCacheContexts(), [
+      'ip.embargo_range',
+    ]);
+  }
+
 }
diff --git a/src/Plugin/search_api/processor/EmbargoProcessor.php b/src/Plugin/search_api/processor/EmbargoProcessor.php
index 82f9613..d1b6a64 100644
--- a/src/Plugin/search_api/processor/EmbargoProcessor.php
+++ b/src/Plugin/search_api/processor/EmbargoProcessor.php
@@ -251,7 +251,7 @@ protected function addEmbargoFilters(string $datasource_id, QueryInterface $quer
         $or_group->addCondition($field->getFieldIdentifier(), $ipRange->id());
         $query->addCacheableDependency($ipRange);
       }
-      $query->addCacheContexts(['ip']);
+      $query->addCacheContexts(['ip.embargo_range']);
     }
 
     return (count($or_group->getConditions()) > 0) ? $or_group : NULL;