From f3ea2ffc2495a246bd889b8f1098976d22fac658 Mon Sep 17 00:00:00 2001
From: "robin.kluth" <robin.kluth@julius-kuehn.de>
Date: Mon, 24 Jul 2023 09:43:17 +0200
Subject: [PATCH] Optional caching

---
 README.md        |  4 +++
 src/LdapAuth.php | 76 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+)

diff --git a/README.md b/README.md
index d243cef..0f3d5cf 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,7 @@ This extensions adds a simple LDAP-Auth mechanism for your yii2 application
 * Read self defined LDAP attributes
 * Domain autodetection based on IPFilter.
 * Filter out results by checking every results `sidHistory`
+* Optional query caching
 
 ## Installation
 
@@ -32,6 +33,9 @@ Either you use it as standalone or add this as component:
       'ldap' => [
             'class' => 'commifreak\yii2\LdapAuth',
             'filterBySidhistory' => false, // Filter by checking sidHistory?
+            'enableCache' => false,
+            'forceApcuCache' => false,
+            'apcuCacheTtl' => 3600,
             'domains' => [
                 ['name' => 'Domain1', 'hostname' => 'domain1.tld', 'autodetectIps' => ['172.31.0.0/16', '192.168.178.0/24', '127.0.0.1'], 'baseDn' => 'DC=Domain1,DC=tld', 'publicSearchUser' => 'example@domain', 'publicSearchUserPassword' => 'secret'],
                 ['name' => 'Domain2', 'hostname' => '192.168.178.14', 'autodetectIps' => ['192.168.178.55'], 'baseDn' => 'DC=Domain2,DC=tld', 'publicSearchUser' => 'example@domain', 'publicSearchUserPassword' => 'secret'],
diff --git a/src/LdapAuth.php b/src/LdapAuth.php
index 7a16586..d5c3c59 100644
--- a/src/LdapAuth.php
+++ b/src/LdapAuth.php
@@ -46,6 +46,24 @@ class LdapAuth extends BaseObject
      */
     public $filterBySidhistory = false;
 
+    /**
+     * Enable optional object caching. Uses Yii::$app->cache component. Or enable APCu with `forceApcuCache`
+     * @var bool
+     */
+    public $enableCache = false;
+
+    /**
+     * Force the use of APCu caching instead of the Yii2 cache component
+     * @var bool
+     */
+    public $forceApcuCache = false;
+
+    /**
+     * Time in seconds objects are cached, if `forceApcuCache` is enabled!
+     * @var int
+     */
+    public $apcuCacheTtl = 3600;
+
     private $_ldapBaseDn;
     private $_l;
     private $_username;
@@ -59,6 +77,15 @@ public function init()
             throw new Exception("LDAP-extension missing :(");
         }
 
+        // Check for APCu missing if not cli.
+        if (php_sapi_name() != 'cli' && $this->enableCache && $this->forceApcuCache && !extension_loaded('apcu')) {
+            throw new Exception("Caching is enabled but APCU is not! :(");
+        }
+
+        if ($this->enableCache && !$this->forceApcuCache && !isset(Yii::$app->cache)) {
+            throw new Exception("Caching is enabled with Yii cache component but its not configured! :(");
+        }
+
         // Sort the domains one time for this run!
         $autoDetectDomainKey = $this->autoDetect();
 
@@ -360,6 +387,34 @@ public function searchUser(?string $searchFor, ?array $attributes = [], ?string
             throw new InvalidArgumentException("Search term is empty but the filter has a placeholder set! Set a term or set a new filter.");
         }
 
+        $cacheKey = 'y2ldap_' . md5($searchFor . (implode("", $attributes)) . $searchFilter);
+        Yii::debug("Cache-Key: " . $cacheKey, __METHOD__);
+
+        if ($this->enableCache) {
+            if (!$this->forceApcuCache) {
+                $storedValue = Yii::$app->cache->get($cacheKey);
+                if ($storedValue) {
+                    Yii::debug("[YII] Returning cached asset", __METHOD__);
+                    return $storedValue;
+                }
+                Yii::debug("Was not cached or invalid", __METHOD__);
+            } else {
+                if (apcu_exists($cacheKey)) {
+                    Yii::debug("Caching enabled and this search is stored!", __METHOD__);
+                    $apcuValue = apcu_fetch($cacheKey);
+                    if ($apcuValue !== false) {
+                        Yii::debug("[APCU] Returning cached asset!", __METHOD__);
+                        return $apcuValue;
+                    }
+                    Yii::warning("Could not return cached asset!", __METHOD__);
+                } else {
+                    Yii::debug("No cache entry!", __METHOD__);
+                }
+            }
+        } else {
+            Yii::debug("Caching disabled", __METHOD__);
+        }
+
         // Default set
         $domains = $this->domains;
 
@@ -471,6 +526,27 @@ public function searchUser(?string $searchFor, ?array $attributes = [], ?string
         Yii::debug("Result:", __METHOD__);
         Yii::debug($return, __METHOD__);
 
+        if ($this->enableCache) {
+            Yii::debug("Adding cache entry", __METHOD__);
+            if (!$this->forceApcuCache) {
+                if (Yii::$app->cache->set($cacheKey, $result)) {
+                    Yii::debug("[YII] Caching succeeded!", __METHOD__);
+                } else {
+                    Yii::warning("[YII] Caching failed!", __METHOD__);
+                }
+            } else {
+                $cacheResult = apcu_store($cacheKey, $return, $this->apcuCacheTtl);
+                if (!$cacheResult) {
+                    Yii::warning("[APCU] Caching was not successful!", __METHOD__);
+                } else {
+                    Yii::debug("[APCU] Cached!", __METHOD__);
+                }
+            }
+        } else {
+            Yii::debug("Not caching: Disabled", __METHOD__);
+        }
+
+
         return empty($return) ? [] : $return;