Added redis auth parameter

Author: sam-sandmann

README.md

@@ -547,7 +547,7 @@ Validate that a Redis service is running.
 <?php
 use ZendDiagnostics\Check\Redis;
 
-$redisCheck = new Redis('localhost', 6379);
+$redisCheck = new Redis('localhost', 6379, 'secret');
 ```
 
 ### SecurityAdvisory

src/ZendDiagnostics/Check/Redis.php

@@ -14,6 +14,11 @@
  */
 class Redis extends AbstractCheck
 {
+    /**
+     * @var string|null
+     */
+    protected $auth;
+
     /**
      * @var string
      */
@@ -25,13 +30,15 @@ class Redis extends AbstractCheck
     protected $port;
 
     /**
-     * @param string  $host
+     * @param string $host
      * @param int $port
+     * @param string|null $auth
      */
-    public function __construct($host = 'localhost', $port = 6379)
+    public function __construct($host = 'localhost', $port = 6379, $auth = null)
     {
         $this->host = $host;
         $this->port = $port;
+        $this->auth = $auth;
     }
 
     /**
@@ -55,16 +62,26 @@ private function createClient()
     {
         if (class_exists('\Redis')) {
             $client = new RedisExtensionClient();
-            $client->connect($this->host);
+            $client->connect($this->host, $this->port);
+
+            if ($this->auth) {
+                $client->auth($this->auth);
+            }
 
             return $client;
         }
 
         if (class_exists('Predis\Client')) {
-            return new PredisClient(array(
+            $parameters = array(
                 'host' => $this->host,
-                'port' => $this->port,
-            ));
+                'port' => $this->port
+            );
+
+            if ($this->auth) {
+                $parameters['password'] = $this->auth;
+            }
+
+            return new PredisClient($parameters);
         }
 
         throw new \RuntimeException('Neither the PHP Redis extension or Predis are installed');