Debug utility to log cache access

plugins/CacheLogPlugin.php

@@ -0,0 +1,96 @@
+<?php
+/**
+ * StatusNet - the distributed open-source microblogging tool
+ * Copyright (C) 2009, StatusNet, Inc.
+ *
+ * Logs cache access
+ *
+ * PHP version 5
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @category  Cache
+ * @package   StatusNet
+ * @author    Evan Prodromou <evan@status.net>
+ * @copyright 2009 StatusNet, Inc.
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
+ * @link      http://status.net/
+ */
+
+if (!defined('STATUSNET')) {
+    // This check helps protect against security problems;
+    // your code file can't be executed directly from the web.
+    exit(1);
+}
+
+/**
+ * Log cache access
+ *
+ * Note that since most caching plugins return false for StartCache*
+ * methods, you should add this plugin before them, i.e.
+ *
+ *     addPlugin('CacheLog');
+ *     addPlugin('XCache');
+ *
+ * @category  Cache
+ * @package   StatusNet
+ * @author    Evan Prodromou <evan@status.net>
+ * @copyright 2009 StatusNet, Inc.
+ * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
+ * @link      http://status.net/
+ */
+
+class CacheLogPlugin extends Plugin
+{
+    function onStartCacheGet(&$key, &$value)
+    {
+        $this->log(LOG_INFO, "Fetching key '$key'");
+        return true;
+    }
+
+    function onEndCacheGet($key, &$value)
+    {
+        if (is_null($value)) {
+            $this->log(LOG_INFO, "Cache MISS for key '$key'");
+        } else {
+            $this->log(LOG_INFO, "Cache HIT for key '$key'");
+        }
+        return true;
+    }
+
+    function onStartCacheSet(&$key, &$value, &$flag, &$expiry, &$success)
+    {
+        $this->log(LOG_INFO, "Setting cache value for key '$key'");
+        return true;
+    }
+
+    function onEndCacheSet($key, $value, $flag, $expiry)
+    {
+        $this->log(LOG_INFO, "Done setting cache value for key '$key'");
+        return true;
+    }
+
+    function onStartCacheDelete(&$key, &$success)
+    {
+        $this->log(LOG_INFO, "Deleting cache value for key '$key'");
+        return true;
+    }
+
+    function onEndCacheDelete($key)
+    {
+        $this->log(LOG_INFO, "Done deleting cache value for key '$key'");
+        return true;
+    }
+}
+