From 39998d323d4a56baf03d00a2fc9ac0fade49bbcd Mon Sep 17 00:00:00 2001
From: William Arslett <will@arslett.uk>
Date: Thu, 21 Jul 2022 09:15:48 +0100
Subject: [PATCH] [Cache] Ensured that redis adapter can use multiple redis
 sentinel hosts

---
 .github/workflows/integration-tests.yml       |  2 +-
 .../Adapter/RedisAdapterSentinelTest.php      |  6 ++--
 .../Component/Cache/Traits/RedisTrait.php     | 28 ++++++++++++-------
 3 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/.github/workflows/integration-tests.yml b/.github/workflows/integration-tests.yml
index e9ea1900a2433..74e7cb078d38d 100644
--- a/.github/workflows/integration-tests.yml
+++ b/.github/workflows/integration-tests.yml
@@ -171,7 +171,7 @@ jobs:
         env:
           REDIS_HOST: 'localhost:16379'
           REDIS_CLUSTER_HOSTS: 'localhost:7000 localhost:7001 localhost:7002 localhost:7003 localhost:7004 localhost:7005'
-          REDIS_SENTINEL_HOSTS: 'localhost:26379'
+          REDIS_SENTINEL_HOSTS: 'localhost:26379 localhost:26379 localhost:26379'
           REDIS_SENTINEL_SERVICE: redis_sentinel
           MESSENGER_REDIS_DSN: redis://127.0.0.1:7006/messages
           MESSENGER_AMQP_DSN: amqp://localhost/%2f/messages
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterSentinelTest.php b/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterSentinelTest.php
index 881630c062d6c..521c5dc4a5579 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterSentinelTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterSentinelTest.php
@@ -47,9 +47,9 @@ public function testInvalidDSNHasBothClusterAndSentinel()
     public function testExceptionMessageWhenFailingToRetrieveMasterInformation()
     {
         $hosts = getenv('REDIS_SENTINEL_HOSTS');
-        $firstHost = explode(' ', $hosts)[0];
+        $dsn = 'redis:?host['.str_replace(' ', ']&host[', $hosts).']';
         $this->expectException(\Symfony\Component\Cache\Exception\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Failed to retrieve master information from master name "invalid-masterset-name" and address "'.$firstHost.'".');
-        AbstractAdapter::createConnection('redis:?host['.str_replace(' ', ']&host[', $hosts).']', ['redis_sentinel' => 'invalid-masterset-name']);
+        $this->expectExceptionMessage('Failed to retrieve master information from sentinel "invalid-masterset-name" and dsn "'.$dsn.'".');
+        AbstractAdapter::createConnection($dsn, ['redis_sentinel' => 'invalid-masterset-name']);
     }
 }
diff --git a/src/Symfony/Component/Cache/Traits/RedisTrait.php b/src/Symfony/Component/Cache/Traits/RedisTrait.php
index dfb5898214f36..accee44bc8e2a 100644
--- a/src/Symfony/Component/Cache/Traits/RedisTrait.php
+++ b/src/Symfony/Component/Cache/Traits/RedisTrait.php
@@ -179,7 +179,7 @@ public static function createConnection(string $dsn, array $options = [])
         }
 
         if (null === $params['class'] && \extension_loaded('redis')) {
-            $class = $params['redis_cluster'] ? \RedisCluster::class : (1 < \count($hosts) ? \RedisArray::class : \Redis::class);
+            $class = $params['redis_cluster'] ? \RedisCluster::class : (1 < \count($hosts) && !isset($params['redis_sentinel']) ? \RedisArray::class : \Redis::class);
         } else {
             $class = $params['class'] ?? \Predis\Client::class;
 
@@ -193,21 +193,29 @@ public static function createConnection(string $dsn, array $options = [])
             $redis = new $class();
 
             $initializer = static function ($redis) use ($connect, $params, $dsn, $auth, $hosts, $tls) {
-                $host = $hosts[0]['host'] ?? $hosts[0]['path'];
-                $port = $hosts[0]['port'] ?? 0;
+                $hostIndex = 0;
+                do {
+                    $host = $hosts[$hostIndex]['host'] ?? $hosts[$hostIndex]['path'];
+                    $port = $hosts[$hostIndex]['port'] ?? 0;
+                    $address = false;
+
+                    if (isset($hosts[$hostIndex]['host']) && $tls) {
+                        $host = 'tls://'.$host;
+                    }
 
-                if (isset($hosts[0]['host']) && $tls) {
-                    $host = 'tls://'.$host;
-                }
+                    if (!isset($params['redis_sentinel'])) {
+                        break;
+                    }
 
-                if (isset($params['redis_sentinel'])) {
                     $sentinel = new \RedisSentinel($host, $port, $params['timeout'], (string) $params['persistent_id'], $params['retry_interval'], $params['read_timeout']);
 
-                    if (!$address = $sentinel->getMasterAddrByName($params['redis_sentinel'])) {
-                        throw new InvalidArgumentException(sprintf('Failed to retrieve master information from master name "%s" and address "%s:%d".', $params['redis_sentinel'], $host, $port));
+                    if ($address = $sentinel->getMasterAddrByName($params['redis_sentinel'])) {
+                        [$host, $port] = $address;
                     }
+                } while (++$hostIndex < \count($hosts) && !$address);
 
-                    [$host, $port] = $address;
+                if (isset($params['redis_sentinel']) && !$address) {
+                    throw new InvalidArgumentException(sprintf('Failed to retrieve master information from sentinel "%s" and dsn "%s".', $params['redis_sentinel'], $dsn));
                 }
 
                 try {