From a037c943bd8deb28ab485ef4408a21992dd78c9e Mon Sep 17 00:00:00 2001
From: Sam Hemelryk <sam@moodle.com>
Date: Thu, 24 Jan 2013 15:09:20 +1300
Subject: [PATCH] MDL-36363 cache: clean up pre-integration

---
 cache/classes/store.php        | 41 ++++++++++++++++++----------------
 cache/locallib.php             |  1 +
 cache/stores/file/lib.php      | 33 +++++++++------------------
 cache/stores/memcache/lib.php  | 23 +++++++++----------
 cache/stores/memcached/lib.php | 27 ++++++++++++----------
 cache/stores/mongodb/lib.php   | 29 +++++++++++++-----------
 cache/stores/session/lib.php   | 13 +----------
 cache/stores/static/lib.php    | 13 +----------
 cache/testperformance.php      |  6 ++---
 cache/upgrade.txt              |  8 +++++++
 10 files changed, 88 insertions(+), 106 deletions(-)
 create mode 100644 cache/upgrade.txt

diff --git a/cache/classes/store.php b/cache/classes/store.php
index 219cda08b38..7cbb069dd95 100644
--- a/cache/classes/store.php
+++ b/cache/classes/store.php
@@ -135,15 +135,6 @@ abstract class cache_store implements cache_store_interface {
      */
     abstract public function __construct($name, array $configuration = array());
 
-    /**
-     * Performs any necessary operation when the store instance has been created.
-     *
-     * @link http://tracker.moodle.org/browse/MDL-36363
-     */
-    public function instance_created() {
-        // By default, do nothing.
-    }
-
     /**
      * Returns the name of this store instance.
      * @return string
@@ -235,23 +226,35 @@ abstract class cache_store implements cache_store_interface {
     /**
      * Performs any necessary clean up when the store instance is being deleted.
      *
-     * Please note that if the store has been already initialised with
-     * a definition ({@link initialise()}), cleanup will be performed against the scope
-     * of that definition i.e. the result depends on the specific store implementation.
-     *
-     * @see instance_deleted()
+     * @deprecated since 2.5
      */
-    abstract public function cleanup();
+    public function cleanup() {
+        debugging('This function has been renamed to instance_deleted. Please update your calls.', DEBUG_DEVELOPER);
+    }
 
     /**
-     * Performs any necessary operation when the store instance is being deleted,
-     * regardless the store being initialised with a definition ({@link initialise()}).
+     * Performs any necessary operation when the store instance has been created.
      *
-     * @link http://tracker.moodle.org/browse/MDL-36363
+     * @since 2.5
+     */
+    public function instance_created() {
+        // By default, do nothing.
+    }
+
+    /**
+     * Performs any necessary operation when the store instance is being deleted.
+     *
+     * This method may be called before the store has been initialised.
+     *
+     * @since 2.5
      * @see cleanup()
      */
     public function instance_deleted() {
-        // By default, do nothing
+        if (method_exists($this, 'cleanup')) {
+            // There used to be a legacy function called cleanup, it was renamed to instance delete.
+            // To be removed in 2.6.
+            $this->cleanup();
+        }
     }
 
     /**
diff --git a/cache/locallib.php b/cache/locallib.php
index 4982719d66d..02dd03eab53 100644
--- a/cache/locallib.php
+++ b/cache/locallib.php
@@ -308,6 +308,7 @@ class cache_config_writer extends cache_config {
                 throw new cache_exception('You cannot delete a cache store that has definition mappings.');
             }
         }
+
         // Call instance_deleted()
         $class = 'cachestore_'.$this->configstores[$name]['plugin'];
         $store = new $class($name, $this->configstores[$name]['configuration']);
diff --git a/cache/stores/file/lib.php b/cache/stores/file/lib.php
index 40d71b1683f..855a223c8c1 100644
--- a/cache/stores/file/lib.php
+++ b/cache/stores/file/lib.php
@@ -46,17 +46,17 @@ class cachestore_file extends cache_store implements cache_is_key_aware, cache_i
     protected $name;
 
     /**
-     * The path to use for the file storage. False otherwise.
-     * @var string
-     */
-    protected $filestorepath = false;
-
-    /**
-     * The path to use when the store instance has been initialised. False otherwise.
+     * The path used to store files for this store and the definition it was initialised with.
      * @var string
      */
     protected $path = false;
 
+    /**
+     * The path in which definition specific sub directories will be created for caching.
+     * @var string
+     */
+    protected $filestorepath = false;
+
     /**
      * Set to true when a prescan has been performed.
      * @var bool
@@ -136,6 +136,7 @@ class cachestore_file extends cache_store implements cache_is_key_aware, cache_i
         }
         $this->isready = $path !== false;
         $this->filestorepath = $path;
+        // This will be updated once the store has been initialised for a definition.
         $this->path = $path;
 
         // Check if we should prescan the directory.
@@ -517,7 +518,6 @@ class cachestore_file extends cache_store implements cache_is_key_aware, cache_i
             }
             $this->keys = array();
         }
-
         return true;
     }
 
@@ -609,22 +609,9 @@ class cachestore_file extends cache_store implements cache_is_key_aware, cache_i
      * 1. Purges the cache directory.
      * 2. Deletes the directory we created for the given definition.
      */
-    public function cleanup() {
-        $this->purge();
-        @rmdir($this->path);
-    }
-
-    /**
-     * Performs any necessary operation when the file store instance is being deleted,
-     * regardless the file store being initialised with a definition ({@link initialise()}).
-     *
-     * @see cleanup()
-     */
     public function instance_deleted() {
-        if ($this->isready && !$this->prescan) {
-            // Remove the content related to this file store.
-            $this->purge_all_definitions();
-        }
+        $this->purge_all_definitions();
+        @rmdir($this->filestorepath);
     }
 
     /**
diff --git a/cache/stores/memcache/lib.php b/cache/stores/memcache/lib.php
index 044831580f2..d25b1c046d8 100644
--- a/cache/stores/memcache/lib.php
+++ b/cache/stores/memcache/lib.php
@@ -319,19 +319,18 @@ class cachestore_memcache extends cache_store implements cache_is_configurable {
     /**
      * Performs any necessary clean up when the store instance is being deleted.
      */
-    public function cleanup() {
-        $this->purge();
-    }
-
-    /**
-     * Performs any necessary operation when the store instance is being deleted,
-     * regardless the store being initialised with a definition ({@link initialise()}).
-     *
-     * @link http://tracker.moodle.org/browse/MDL-36363
-     * @see cleanup()
-     */
     public function instance_deleted() {
-        $this->cleanup();
+        if ($this->connection) {
+            $connection = $this->connection;
+        } else {
+            $connection = new Memcache;
+            foreach ($this->servers as $server) {
+                $connection->addServer($server[0], $server[1], true, $server[2]);
+            }
+        }
+        $connection->flush();
+        unset($connection);
+        unset($this->connection);
     }
 
     /**
diff --git a/cache/stores/memcached/lib.php b/cache/stores/memcached/lib.php
index f49d7077248..4370a6d84b1 100644
--- a/cache/stores/memcached/lib.php
+++ b/cache/stores/memcached/lib.php
@@ -401,19 +401,22 @@ class cachestore_memcached extends cache_store implements cache_is_configurable
     /**
      * Performs any necessary clean up when the store instance is being deleted.
      */
-    public function cleanup() {
-        $this->purge();
-    }
-
-    /**
-     * Performs any necessary operation when the store instance is being deleted,
-     * regardless the store being initialised with a definition ({@link initialise()}).
-     *
-     * @link http://tracker.moodle.org/browse/MDL-36363
-     * @see cleanup()
-     */
     public function instance_deleted() {
-        $this->cleanup();
+        if ($this->connection) {
+            $connection = $this->connection;
+        } else {
+            $connection = new Memcached(crc32($this->name));
+            $servers = $connection->getServerList();
+            if (empty($servers)) {
+                foreach ($this->options as $key => $value) {
+                    $connection->setOption($key, $value);
+                }
+                $connection->addServers($this->servers);
+            }
+        }
+        $connection->flush();
+        unset($connection);
+        unset($this->connection);
     }
 
     /**
diff --git a/cache/stores/mongodb/lib.php b/cache/stores/mongodb/lib.php
index f82b94fbd36..cefc299f4b1 100644
--- a/cache/stores/mongodb/lib.php
+++ b/cache/stores/mongodb/lib.php
@@ -67,7 +67,7 @@ class cachestore_mongodb extends cache_store implements cache_is_configurable {
      * The Connection object
      * @var Mongo
      */
-    protected $connection;
+    protected $connection = false;
 
     /**
      * The Database Object
@@ -439,19 +439,22 @@ class cachestore_mongodb extends cache_store implements cache_is_configurable {
     /**
      * Performs any necessary clean up when the store instance is being deleted.
      */
-    public function cleanup() {
-        $this->purge();
-    }
-
-    /**
-     * Performs any necessary operation when the store instance is being deleted,
-     * regardless the store being initialised with a definition ({@link initialise()}).
-     *
-     * @link http://tracker.moodle.org/browse/MDL-36363
-     * @see cleanup()
-     */
     public function instance_deleted() {
-        $this->cleanup();
+        // We can't use purge here that acts upon a collection.
+        // Instead we must drop the named database.
+        if ($this->connection) {
+            $connection = $this->connection;
+        } else {
+            $connection = new Mongo($this->server, $this->options);
+        }
+        $database = $connection->selectDB($this->databasename);
+        $database->drop();
+        $connection = null;
+        $database = null;
+        // Explicitly unset things to cause a close.
+        $this->collection = null;
+        $this->database = null;
+        $this->connection = null;
     }
 
     /**
diff --git a/cache/stores/session/lib.php b/cache/stores/session/lib.php
index 28b41d70a90..5a2b9a09d00 100644
--- a/cache/stores/session/lib.php
+++ b/cache/stores/session/lib.php
@@ -375,19 +375,8 @@ class cachestore_session extends session_data_store implements cache_is_key_awar
     /**
      * Performs any necessary clean up when the store instance is being deleted.
      */
-    public function cleanup() {
-        $this->purge();
-    }
-
-    /**
-     * Performs any necessary operation when the store instance is being deleted,
-     * regardless the store being initialised with a definition ({@link initialise()}).
-     *
-     * @link http://tracker.moodle.org/browse/MDL-36363
-     * @see cleanup()
-     */
     public function instance_deleted() {
-        $this->cleanup();
+        $this->purge();
     }
 
     /**
diff --git a/cache/stores/static/lib.php b/cache/stores/static/lib.php
index 53b7734487b..6b4ab4ed58d 100644
--- a/cache/stores/static/lib.php
+++ b/cache/stores/static/lib.php
@@ -372,19 +372,8 @@ class cachestore_static extends static_data_store implements cache_is_key_aware
     /**
      * Performs any necessary clean up when the store instance is being deleted.
      */
-    public function cleanup() {
-        $this->purge();
-    }
-
-    /**
-     * Performs any necessary operation when the store instance is being deleted,
-     * regardless the store being initialised with a definition ({@link initialise()}).
-     *
-     * @link http://tracker.moodle.org/browse/MDL-36363
-     * @see cleanup()
-     */
     public function instance_deleted() {
-        $this->cleanup();
+        $this->purge();
     }
 
     /**
diff --git a/cache/testperformance.php b/cache/testperformance.php
index 26796c1afcc..a4704dc25c8 100644
--- a/cache/testperformance.php
+++ b/cache/testperformance.php
@@ -100,7 +100,7 @@ foreach (get_plugin_list_with_file('cachestore', 'lib.php', true) as $plugin =>
             }
             $result[5] = sprintf('%01.4f', microtime(true) - $start);
             $applicationtable->data[] = $result;
-            $store->cleanup();
+            $store->instance_deleted();
         }
     }
 
@@ -136,7 +136,7 @@ foreach (get_plugin_list_with_file('cachestore', 'lib.php', true) as $plugin =>
             }
             $result[5] = sprintf('%01.4f', microtime(true) - $start);
             $sessiontable->data[] = $result;
-            $store->cleanup();
+            $store->instance_deleted();
         }
     }
 
@@ -172,7 +172,7 @@ foreach (get_plugin_list_with_file('cachestore', 'lib.php', true) as $plugin =>
             }
             $result[5] = sprintf('%01.4f', microtime(true) - $start);
             $requesttable->data[] = $result;
-            $store->cleanup();
+            $store->instance_deleted();
         }
     }
 
diff --git a/cache/upgrade.txt b/cache/upgrade.txt
new file mode 100644
index 00000000000..72ac93bda2e
--- /dev/null
+++ b/cache/upgrade.txt
@@ -0,0 +1,8 @@
+This files describes API changes in /cache/stores/* - cache store plugins.
+Information provided here is intended especially for developers.
+
+=== 2.5 ===
+* cleanup method renamed to instance_deleted.
+  It is now called when the store is deleted as all comments suggested anyway.
+* instance_created method added.
+  It is called when the store is created for the very first time.
\ No newline at end of file