minor #28691 [Cache] add RedisClusterProxy to create lazy connections to Redis clusters (alekitto)

This PR was merged into the 4.2-dev branch.

Discussion
----------

[Cache] add RedisClusterProxy to create lazy connections to Redis clusters

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Code provided by @alekitto in #28300
I'm working on an alternative to this PR, but these bits are required.

Commits
-------

239a022cc0 [Cache] add RedisClusterProxy to create lazy connections to Redis clusters

src/Symfony/Component/Cache/Traits/RedisClusterProxy.php

@@ -0,0 +1,63 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Cache\Traits;
+
+/**
+ * @author Alessandro Chitolina <alekitto@gmail.com>
+ *
+ * @internal
+ */
+class RedisClusterProxy
+{
+    private $redis;
+    private $initializer;
+
+    public function __construct(\Closure $initializer)
+    {
+        $this->initializer = $initializer;
+    }
+
+    public function __call($method, array $args)
+    {
+        $this->redis ?: $this->redis = $this->initializer->__invoke();
+
+        return $this->redis->{$method}(...$args);
+    }
+
+    public function hscan($strKey, &$iIterator, $strPattern = null, $iCount = null)
+    {
+        $this->redis ?: $this->redis = $this->initializer->__invoke();
+
+        return $this->redis->hscan($strKey, $iIterator, $strPattern, $iCount);
+    }
+
+    public function scan(&$iIterator, $strPattern = null, $iCount = null)
+    {
+        $this->redis ?: $this->redis = $this->initializer->__invoke();
+
+        return $this->redis->scan($iIterator, $strPattern, $iCount);
+    }
+
+    public function sscan($strKey, &$iIterator, $strPattern = null, $iCount = null)
+    {
+        $this->redis ?: $this->redis = $this->initializer->__invoke();
+
+        return $this->redis->sscan($strKey, $iIterator, $strPattern, $iCount);
+    }
+
+    public function zscan($strKey, &$iIterator, $strPattern = null, $iCount = null)
+    {
+        $this->redis ?: $this->redis = $this->initializer->__invoke();
+
+        return $this->redis->zscan($strKey, $iIterator, $strPattern, $iCount);
+    }
+}

src/Symfony/Component/Cache/Traits/RedisTrait.php

@@ -52,7 +52,7 @@ trait RedisTrait
         if (preg_match('#[^-+_.A-Za-z0-9]#', $namespace, $match)) {
             throw new InvalidArgumentException(sprintf('RedisAdapter namespace contains "%s" but only characters in [-+_.A-Za-z0-9] are allowed.', $match[0]));
         }
-        if (!$redisClient instanceof \Redis && !$redisClient instanceof \RedisArray && !$redisClient instanceof \RedisCluster && !$redisClient instanceof \Predis\Client && !$redisClient instanceof RedisProxy) {
+        if (!$redisClient instanceof \Redis && !$redisClient instanceof \RedisArray && !$redisClient instanceof \RedisCluster && !$redisClient instanceof \Predis\Client && !$redisClient instanceof RedisProxy && !$redisClient instanceof RedisClusterProxy) {
             throw new InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, \is_object($redisClient) ? \get_class($redisClient) : \gettype($redisClient)));
         }
         $this->redis = $redisClient;
@@ -237,7 +237,7 @@ trait RedisTrait
             foreach ($this->redis->_hosts() as $host) {
                 $hosts[] = $this->redis->_instance($host);
             }
-        } elseif ($this->redis instanceof \RedisCluster) {
+        } elseif ($this->redis instanceof RedisClusterProxy || $this->redis instanceof \RedisCluster) {
             $hosts = array();
             foreach ($this->redis->_masters() as $host) {
                 $hosts[] = $h = new \Redis();
@@ -330,7 +330,7 @@ trait RedisTrait
     {
         $ids = array();
 
-        if ($this->redis instanceof \RedisCluster || ($this->redis instanceof \Predis\Client && $this->redis->getConnection() instanceof RedisCluster)) {
+        if ($this->redis instanceof RedisClusterProxy || $this->redis instanceof \RedisCluster || ($this->redis instanceof \Predis\Client && $this->redis->getConnection() instanceof RedisCluster)) {
             // phpredis & predis don't support pipelining with RedisCluster
             // see https://github.com/phpredis/phpredis/blob/develop/cluster.markdown#pipelining
             // see https://github.com/nrk/predis/issues/267#issuecomment-123781423

src/Symfony/Component/HttpFoundation/Session/Storage/Handler/RedisSessionHandler.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\HttpFoundation\Session\Storage\Handler;
 
 use Predis\Response\ErrorInterface;
+use Symfony\Component\Cache\Traits\RedisClusterProxy;
 use Symfony\Component\Cache\Traits\RedisProxy;
 
 /**
@@ -45,7 +46,8 @@ class RedisSessionHandler extends AbstractSessionHandler
             !$redis instanceof \RedisArray &&
             !$redis instanceof \RedisCluster &&
             !$redis instanceof \Predis\Client &&
-            !$redis instanceof RedisProxy
+            !$redis instanceof RedisProxy &&
+            !$redis instanceof RedisClusterProxy
         ) {
             throw new \InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, \is_object($redis) ? \get_class($redis) : \gettype($redis)));
         }

src/Symfony/Component/Lock/Store/RedisStore.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Lock\Store;
 
+use Symfony\Component\Cache\Traits\RedisClusterProxy;
 use Symfony\Component\Cache\Traits\RedisProxy;
 use Symfony\Component\Lock\Exception\InvalidArgumentException;
 use Symfony\Component\Lock\Exception\LockConflictedException;
@@ -130,7 +131,12 @@ class RedisStore implements StoreInterface
      */
     private function evaluate(string $script, string $resource, array $args)
     {
-        if ($this->redis instanceof \Redis || $this->redis instanceof \RedisCluster || $this->redis instanceof RedisProxy) {
+        if (
+            $this->redis instanceof \Redis ||
+            $this->redis instanceof \RedisCluster ||
+            $this->redis instanceof RedisProxy ||
+            $this->redis instanceof RedisClusterProxy
+        ) {
             return $this->redis->eval($script, array_merge(array($resource), $args), 1);
         }
 

src/Symfony/Component/Lock/Store/StoreFactory.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Lock\Store;
 
+use Symfony\Component\Cache\Traits\RedisClusterProxy;
 use Symfony\Component\Cache\Traits\RedisProxy;
 use Symfony\Component\Lock\Exception\InvalidArgumentException;
 
@@ -28,7 +29,14 @@ class StoreFactory
      */
     public static function createStore($connection)
     {
-        if ($connection instanceof \Redis || $connection instanceof \RedisArray || $connection instanceof \RedisCluster || $connection instanceof \Predis\Client || $connection instanceof RedisProxy) {
+        if (
+            $connection instanceof \Redis ||
+            $connection instanceof \RedisArray ||
+            $connection instanceof \RedisCluster ||
+            $connection instanceof \Predis\Client ||
+            $connection instanceof RedisProxy ||
+            $connection instanceof RedisClusterProxy
+        ) {
             return new RedisStore($connection);
         }
         if ($connection instanceof \Memcached) {