Add method to get connection factory from redis-cluster connection.

src/Connection/Aggregate/RedisCluster.php

@@ -497,6 +497,17 @@ class RedisCluster implements ClusterInterface, IteratorAggregate, Countable
         return $this->strategy;
     }
 
+    /**
+     * Returns the underlying connection factory used to create new connection
+     * instances to Redis nodes indicated by redis-cluster.
+     *
+     * @return FactoryInterface
+     */
+    public function getConnectionFactory()
+    {
+        return $this->connections;
+    }
+
     /**
      * Enables automatic fetching of the current slots map from one of the nodes
      * using the CLUSTER NODES command. This option is disabled by default but

tests/Predis/Connection/Aggregate/RedisClusterTest.php

@@ -22,6 +22,17 @@ use Predis\Response;
  */
 class RedisClusterTest extends PredisTestCase
 {
+    /**
+     * @group disconnected
+     */
+    public function testAcceptsCustomConnectionFactory()
+    {
+        $factory = $this->getMock('Predis\Connection\FactoryInterface');
+        $cluster = new RedisCluster($factory);
+
+        $this->assertSame($factory, $cluster->getConnectionFactory());
+    }
+
     /**
      * @group disconnected
      */