1 files changed, 166 insertions, 0 deletions
diff --git a/library/Director/Db/Cache/PrefetchCache.php b/library/Director/Db/Cache/PrefetchCache.php
new file mode 100644
index 0000000..aa9f950
--- /dev/null
+++ b/library/Director/Db/Cache/PrefetchCache.php
@@ -0,0 +1,166 @@
+<?php
+
+namespace Icinga\Module\Director\Db\Cache;
+
+use Icinga\Module\Director\CustomVariable\CustomVariable;
+use Icinga\Module\Director\Data\Db\DbObject;
+use Icinga\Module\Director\Db;
+use Icinga\Module\Director\Objects\IcingaObject;
+use Icinga\Module\Director\Resolver\HostServiceBlacklist;
+use Icinga\Module\Director\Resolver\TemplateTree;
+use LogicException;
+
+/**
+ * Central prefetch cache
+ *
+ * Might be improved, accept various caches based on an interface and then
+ * finally replace prefetch logic in DbObject itself. This would also allow
+ * to get rid of IcingaObject-related code in this place
+ */
+class PrefetchCache
+{
+    protected $db;
+
+    protected static $instance;
+
+    protected $varsCaches = array();
+
+    protected $groupsCaches = array();
+
+    protected $templateResolvers = array();
+
+    protected $renderedVars = array();
+
+    protected $templateTrees = array();
+
+    protected $hostServiceBlacklist;
+
+    public static function initialize(Db $db)
+    {
+        self::forget();
+        self::$instance = new static($db);
+    }
+
+    protected function __construct(Db $db)
+    {
+        $this->db = $db;
+    }
+
+    /**
+     * @throws LogicException
+     *
+     * @return self
+     */
+    public static function instance()
+    {
+        if (static::$instance === null) {
+            throw new LogicException('Prefetch cache has not been loaded');
+        }
+
+        return static::$instance;
+    }
+
+    public static function forget()
+    {
+        DbObject::clearAllPrefetchCaches();
+        self::$instance = null;
+    }
+
+    public static function shouldBeUsed()
+    {
+        return self::$instance !== null;
+    }
+
+    public function vars(IcingaObject $object)
+    {
+        return $this->varsCache($object)->getVarsForObject($object);
+    }
+
+    public function groups(IcingaObject $object)
+    {
+        return $this->groupsCache($object)->getGroupsForObject($object);
+    }
+
+    /* Hint: not implemented, this happens in DbObject right now
+    public function byObjectType($type)
+    {
+        if (! array_key_exists($type, $this->caches)) {
+            $this->caches[$type] = new ObjectCache($type);
+        }
+
+        return $this->caches[$type];
+    }
+    */
+
+    public function renderVar(CustomVariable $var, $renderExpressions = false)
+    {
+        $checksum = $var->getChecksum();
+        if (null === $checksum) {
+            return $var->toConfigString($renderExpressions);
+        } else {
+            $checksum .= (int) $renderExpressions;
+            if (! array_key_exists($checksum, $this->renderedVars)) {
+                $this->renderedVars[$checksum] = $var->toConfigString($renderExpressions);
+            }
+
+            return $this->renderedVars[$checksum];
+        }
+    }
+
+    public function hostServiceBlacklist()
+    {
+        if ($this->hostServiceBlacklist === null) {
+            $this->hostServiceBlacklist = new HostServiceBlacklist($this->db);
+            $this->hostServiceBlacklist->preloadMappings();
+        }
+
+        return $this->hostServiceBlacklist;
+    }
+
+    /**
+     * @param IcingaObject $object
+     * @return CustomVariableCache
+     */
+    protected function varsCache(IcingaObject $object)
+    {
+        $key = $object->getShortTableName();
+
+        if (! array_key_exists($key, $this->varsCaches)) {
+            $this->varsCaches[$key] = new CustomVariableCache($object);
+        }
+
+        return $this->varsCaches[$key];
+    }
+
+    protected function groupsCache(IcingaObject $object)
+    {
+        $key = $object->getShortTableName();
+
+        if (! array_key_exists($key, $this->groupsCaches)) {
+            $this->groupsCaches[$key] = new GroupMembershipCache($object);
+        }
+
+        return $this->groupsCaches[$key];
+    }
+
+    protected function templateTree(IcingaObject $object)
+    {
+        $key = $object->getShortTableName();
+        if (! array_key_exists($key, $this->templateTrees)) {
+            $this->templateTrees[$key] = new TemplateTree(
+                $key,
+                $object->getConnection()
+            );
+        }
+
+        return $this->templateTrees[$key];
+    }
+
+    public function __destruct()
+    {
+        unset($this->groupsCaches);
+        unset($this->varsCaches);
+        unset($this->templateResolvers);
+        unset($this->renderedVars);
+    }
+}