Add Redis session handler (#1460)

composer.json

@@ -12,6 +12,7 @@
         "php": ">=7.1",
         "ahand/mobileesp": "dev-master",
         "cap60552/php-sip2": "1.0.0",
+        "colinmollenhour/credis": "1.10.1",
         "endroid/qr-code": "3.5.8",
         "ghislainf/zf2-whoops": "dev-master#2649cf7caf400409942ddc3f8fe15b89381fc74e",
         "jasig/phpcas": "1.3.7",

config/vufind/config.ini

@@ -151,7 +151,7 @@ nonJavascriptSupportEnabled = false
 generator = "VuFind 6.0"
 
 ; This section allows you to configure the mechanism used for storing user
-; sessions.  Available types: File, Memcache, Database.
+; sessions.  Available types: File, Memcache, Database, Redis.
 ; Some of the settings below only apply to specific session handlers;
 ; such settings are named with an obvious prefix.  Non-prefixed settings
 ; are global to all handlers.
@@ -169,6 +169,15 @@ secure = false
 ;memcache_host               = localhost
 ;memcache_port               = 11211
 ;memcache_connection_timeout = 1
+;
+; Settings related to Redis-based sessions; default values are listed below
+;redis_host               = localhost
+;redis_port               = 6379
+;redis_connection_timeout = 0.5
+;redis_db                 = 0
+;redis_auth               = some_secret_password
+;redis_version            = 3
+;redis_standalone         = true
 
 ; This section controls how VuFind creates cookies (to store session IDs, bookbag
 ; contents, theme/language settings, etc.)

module/VuFind/src/VuFind/Session/PluginManager.php

@@ -52,6 +52,7 @@ class PluginManager extends \VuFind\ServiceManager\AbstractPluginManager
         'database' => Database::class,
         'file' => File::class,
         'memcache' => Memcache::class,
+        'redis' => Redis::class,
         // for legacy 1.x compatibility
         'filesession' => File::class,
         'memcachesession' => Memcache::class,
@@ -67,6 +68,7 @@ class PluginManager extends \VuFind\ServiceManager\AbstractPluginManager
         Database::class => InvokableFactory::class,
         File::class => InvokableFactory::class,
         Memcache::class => InvokableFactory::class,
+        Redis::class => InvokableFactory::class,
     ];
 
     /**
@@ -78,6 +80,7 @@ class PluginManager extends \VuFind\ServiceManager\AbstractPluginManager
         Database::class => [SecureDelegatorFactory::class],
         File::class => [SecureDelegatorFactory::class],
         Memcache::class => [SecureDelegatorFactory::class],
+        Redis::class => [SecureDelegatorFactory::class],
     ];
 
     /**

module/VuFind/src/VuFind/Session/Redis.php

+<?php
+/**
+ * Redis session handler
+ *
+ * Note: Using phpredis extension (see https://github.com/phpredis/phpredis) is
+ * optional, this class use Credis in standalone mode by default
+ *
+ * PHP version 7
+ *
+ * Coypright (C) Moravian Library 2019.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2,
+ * as published by the Free Software Foundation.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * @category VuFind
+ * @package  Session_Handlers
+ * @author   Veros Kaplan <cpk-dev@mzk.cz>
+ * @author   Josef Moravec <moravec@mzk.cz>
+ * @license  http://opensource.org/licenses/gpl-2.0.php GNU General Public License
+ * @link     http://vufind.org/wiki/vufind2:session_handlers Wiki
+ */
+namespace VuFind\Session;
+
+/**
+ * Redis session handler
+ *
+ * @category VuFind
+ * @package  Session_Handlers
+ * @author   Veros Kaplan <cpk-dev@mzk.cz>
+ * @author   Josef Moravec <moravec@mzk.cz>
+ * @license  http://opensource.org/licenses/gpl-2.0.php GNU General Public License
+ * @link     http://vufind.org/wiki/vufind2:session_handlers Wiki
+ */
+class Redis extends AbstractBase
+{
+    /**
+     * Redis connection
+     *
+     * @var \Credis_Client
+     */
+    protected $connection = false;
+
+    /**
+     * Redis version
+     *
+     * @var int
+     */
+    protected $redisVersion = 3;
+
+    /**
+     * Get connection to Redis
+     *
+     * @throws \Exception
+     * @return \Credis_Client
+     */
+    protected function getConnection()
+    {
+        if (!$this->connection) {
+            // Set defaults if nothing set in config file.
+            $host = $this->config->redis_host ?? 'localhost';
+            $port = $this->config->redis_port ?? 6379;
+            $timeout = $this->config->redis_connection_timeout ?? 0.5;
+            $auth = $this->config->redis_auth ?? false;
+            $redis_db = $this->config->redis_db ?? 0;
+            $this->redisVersion = int($this->config->redis_version ?? 3);
+            $standalone = bool($this->config->redis_standalone ?? true);
+
+            // Create Credis client, the connection is established lazily
+            $this->connection = new \Credis_Client(
+                $host, $port, $timeout, '', $redis_db, $auth
+            );
+            if ($standalone) {
+                $this->connection->forceStandalone();
+            }
+        }
+        return $this->connection;
+    }
+
+    /**
+     * Read function must return string value always to make save handler work as
+     * expected. Return empty string if there is no data to read.
+     *
+     * @param string $sess_id The session ID to read
+     *
+     * @return string
+     */
+    public function read($sess_id)
+    {
+        $session = $this->getConnection()->get("vufind_sessions/{$sess_id}");
+        return $session !== false ? $session : '';
+    }
+
+    /**
+     * Write function that is called when session data is to be saved.
+     *
+     * @param string $sess_id The current session ID
+     * @param string $data    The session data to write
+     *
+     * @return bool
+     */
+    public function write($sess_id, $data)
+    {
+        return $this->getConnection()->setex(
+            "vufind_sessions/{$sess_id}", $this->lifetime, $data
+        );
+    }
+
+    /**
+     * The destroy handler, this is executed when a session is destroyed with
+     * session_destroy() and takes the session id as its only parameter.
+     *
+     * @param string $sess_id The session ID to destroy
+     *
+     * @return void
+     */
+    public function destroy($sess_id)
+    {
+        // Perform standard actions required by all session methods:
+        parent::destroy($sess_id);
+
+        // Perform Redis-specific cleanup
+        if ($this->redisVersion >= 4) {
+            $this->getConnection()->unlink("vufind_sessions/{$sess_id}");
+        } else {
+            $this->getConnection()->del("vufind_sessions/{$sess_id}");
+        }
+    }
+}