refs #23 support for Redis sentinel by using a different backend

Queue/Backend.php

@@ -32,4 +32,6 @@ public function deleteIfKeyHasValue($key, $value);
     public function expireIfKeyHasValue($key, $value, $ttlInSeconds);
 
     public function get($key);
+
+    public function getKeysMatchingPattern($pattern);
 }

Queue/Backend/Redis.php

@@ -11,23 +11,22 @@
 use Piwik\Log;
 use Piwik\Plugins\QueuedTracking\Queue\Backend;
 use Piwik\Tracker;
-use Piwik\Translate;
 
 class Redis implements Backend
 {
     /**
      * @var \Redis
      */
-    private $redis;
-    private $host;
-    private $port;
-    private $timeout;
-    private $password;
+    protected $redis;
+    protected $host;
+    protected $port;
+    protected $timeout;
+    protected $password;
 
     /**
      * @var int
      */
-    private $database;
+    protected $database;
 
     public function testConnection()
     {
@@ -162,8 +161,14 @@ public function deleteIfKeyHasValue($key, $value)
 else
     return 0
 end';
+
         // ideally we would use evalSha to reduce bandwidth!
-        return (bool) $this->redis->eval($script, array($key, $value), 1);
+        return (bool) $this->evalScript($script, array($key), array($value));
+    }
+
+    protected function evalScript($script, $keys, $args)
+    {
+        return $this->redis->eval($script, array_merge($keys, $args), count($keys));
     }
 
     public function getKeysMatchingPattern($pattern)
@@ -187,7 +192,7 @@ public function expireIfKeyHasValue($key, $value, $ttlInSeconds)
     return 0
 end';
         // ideally we would use evalSha to reduce bandwidth!
-        return (bool) $this->redis->eval($script, array($key, $value, (int) $ttlInSeconds), 1);
+        return (bool) $this->evalScript($script, array($key), array($value, (int) $ttlInSeconds));
     }
 
     public function get($key)
@@ -213,7 +218,7 @@ private function connectIfNeeded()
         }
     }
 
-    private function connect()
+    protected function connect()
     {
         $this->redis = new \Redis();
         $success = $this->redis->connect($this->host, $this->port, $this->timeout, null, 100);
@@ -235,8 +240,11 @@ public function setConfig($host, $port, $timeout, $password)
 
         $this->host = $host;
         $this->port = $port;
-        $this->timeout  = $timeout;
-        $this->password = $password;
+        $this->timeout = $timeout;
+
+        if (!empty($password)) {
+            $this->password = $password;
+        }
     }
 
     private function disconnect()

Queue/Backend/Sentinel.php

@@ -0,0 +1,36 @@
+<?php
+/**
+ * Piwik - free/libre analytics platform
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\Plugins\QueuedTracking\Queue\Backend;
+
+use Piwik\Plugins\QueuedTracking\Queue\Backend;
+use Piwik\Tracker;
+
+include_once PIWIK_INCLUDE_PATH . '/plugins/QueuedTracking/libs/credis/Client.php';
+include_once PIWIK_INCLUDE_PATH . '/plugins/QueuedTracking/libs/credis/Cluster.php';
+include_once PIWIK_INCLUDE_PATH . '/plugins/QueuedTracking/libs/credis/Sentinel.php';
+
+class Sentinel extends Redis
+{
+    protected function connect()
+    {
+        $client = new \Credis_Client($this->host, $this->port, $this->timeout, $persistent = false, $this->database, $this->password);
+        $this->redis = new \Credis_Sentinel($client);
+        $client->connect();
+
+        $this->redis = $client;
+
+        return true;
+    }
+
+    protected function evalScript($script, $keys, $args)
+    {
+        return $this->redis->eval($script, $keys, $args);
+    }
+
+}

Queue/Factory.php

@@ -9,6 +9,7 @@
 
 namespace Piwik\Plugins\QueuedTracking\Queue;
 
+use Piwik\Config;
 use Piwik\Container\StaticContainer;
 use Piwik\Plugins\QueuedTracking\Queue;
 use Piwik\Plugins\QueuedTracking\Settings;
@@ -48,6 +49,11 @@ public static function getSettings()
         return StaticContainer::get('Piwik\Plugins\QueuedTracking\Settings');
     }
 
+    private static function getConfig()
+    {
+        return Config::getInstance();
+    }
+
     private static function makeBackendFromSettings(Settings $settings)
     {
         $host     = $settings->redisHost->getValue();
@@ -56,7 +62,13 @@ private static function makeBackendFromSettings(Settings $settings)
         $password = $settings->redisPassword->getValue();
         $database = $settings->redisDatabase->getValue();
 
-        $redis = new Queue\Backend\Redis();
+        $queuedTracking = self::getConfig()->QueuedTracking;
+        if (!empty($queuedTracking['backend']) && $queuedTracking['backend'] === 'sentinel') {
+            $redis = new Queue\Backend\Sentinel();
+        } else {
+            $redis = new Queue\Backend\Redis();
+        }
+
         $redis->setConfig($host, $port, $timeout, $password);
         $redis->setDatabase($database);
 

Queue/Lock.php

@@ -11,12 +11,11 @@
 use Piwik\Common;
 use Piwik\Plugins\QueuedTracking\Queue\Backend;
 use Piwik\Tracker;
-use Piwik\Plugins\QueuedTracking\Queue\Backend\Redis;
 
 class Lock
 {
     /**
-     * @var Redis
+     * @var Backend
      */
     private $backend;
 

Queue/Manager.php

@@ -13,12 +13,11 @@
 use Piwik\Plugins\QueuedTracking\Queue\Backend;
 use Piwik\Tracker\RequestSet;
 use Piwik\Tracker;
-use Piwik\Plugins\QueuedTracking\Queue\Backend\Redis;
 
 class Manager
 {
     /**
-     * @var Redis
+     * @var Backend
      */
     private $backend;
 

README.md

@@ -75,7 +75,7 @@ __How should the redis server be configured?__
 Make sure to have enough memory to save all tracking requests in the queue. One tracking request in the queue takes about 2KB,
 20.000 tracking requests take about 50MB. All tracking requests of all websites are stored in the same queue.
 There should be only one Redis server to make sure the data will be replayed in the same order as they were recorded.
-If you want to configure Redis HA (High Availability) it should be possible to use Redis Cluser, Redis Sentinel, ...
+If you want to configure Redis HA (High Availability) it is possible to use Redis Sentinel see further down.
 We currently write into the Redis default database by default but you can configure to use a different one.
 
 __Why do some tests fail on my local Piwik instance?__
@@ -124,6 +124,17 @@ __I am using the Log Importer in combination with Queued Tracking, is there some
 
 Yes, we recommend to set the "Number of requests to process" to `1` as the log importer usually sends multiple requests at once using bulk tracking already.
 
+__How can I configure the QueuedTracking plugin to use Sentinel?__
+
+Add the following configuration to your `config/config.ini.php` to enable Sentinel feature:
+
+```
+[QueuedTracking]
+backend=sentinel
+```
+
+In this case the `phpredis` extension is not needed as it uses a PHP class to connect to your Redis. Please note that calls to Redis might be a little bit slower.
+
 __Are there any known issues?__
 
 * In case you are using bulk tracking the bulk tracking response varies compared to the regular one. We will always return
@@ -134,6 +145,10 @@ __Are there any known issues?__
 
 ## Changelog
 
+0.3.0
+
+- Added support to use Redis Sentinel for automatic failover
+
 0.2.5
 
 - Use a better random number generator if available on the system to more evenly process queues.