From: Robin Appelman <robin@icewind.nl>
Date: Thu, 18 Jul 2024 15:16:01 +0000 (+0200)
Subject: fix: only allow pre-defined shards
X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=fc05a67f192eb96870b02f574d14318792c46cf5;p=nextcloud-server.git

fix: only allow pre-defined shards

Signed-off-by: Robin Appelman <robin@icewind.nl>
---

diff --git a/lib/private/DB/Connection.php b/lib/private/DB/Connection.php
index 447c164c1a4..3cb8ea17aed 100644
--- a/lib/private/DB/Connection.php
+++ b/lib/private/DB/Connection.php
@@ -92,6 +92,21 @@ class Connection extends PrimaryReadReplicaConnection {
 	protected ShardConnectionManager $shardConnectionManager;
 	protected AutoIncrementHandler $autoIncrementHandler;
 
+	public const SHARD_PRESETS = [
+		'filecache' => [
+			'companion_keys' => [
+				'file_id',
+			],
+			'companion_tables' => [
+				'filecache_extended',
+				'files_metadata',
+			],
+			'primary_key' => 'fileid',
+			'shard_key' => 'storage',
+			'table' => 'filecache',
+		],
+	];
+
 	/**
 	 * Initializes a new instance of the Connection class.
 	 *
@@ -141,23 +156,30 @@ class Connection extends PrimaryReadReplicaConnection {
 			$this->_config->setSQLLogger($debugStack);
 		}
 
-		// todo: only allow specific, pre-defined shard configurations, the current config exists for easy testing setup
-		$this->shards = array_map(function (array $config) {
+		/** @var array<string, array{shards: array[], mapper: ?string}> $shardConfig */
+		$shardConfig = $this->params['sharding'] ?? [];
+		$shardNames = array_keys($shardConfig);
+		$this->shards = array_map(function (array $config, string $name) {
+			if (!isset(self::SHARD_PRESETS[$name])) {
+				throw new \Exception("Shard preset $name not found");
+			}
+
 			$shardMapperClass = $config['mapper'] ?? RoundRobinShardMapper::class;
 			$shardMapper = Server::get($shardMapperClass);
 			if (!$shardMapper instanceof IShardMapper) {
 				throw new \Exception("Invalid shard mapper: $shardMapperClass");
 			}
 			return new ShardDefinition(
-				$config['table'],
-				$config['primary_key'],
-				$config['companion_keys'],
-				$config['shard_key'],
+				self::SHARD_PRESETS[$name]['table'],
+				self::SHARD_PRESETS[$name]['primary_key'],
+				self::SHARD_PRESETS[$name]['companion_keys'],
+				self::SHARD_PRESETS[$name]['shard_key'],
 				$shardMapper,
-				$config['companion_tables'],
+				self::SHARD_PRESETS[$name]['companion_tables'],
 				$config['shards']
 			);
-		}, $this->params['sharding']);
+		}, $shardConfig, $shardNames);
+		$this->shards = array_combine($shardNames, $this->shards);
 		$this->partitions = array_map(function (ShardDefinition $shard) {
 			return array_merge([$shard->table], $shard->companionTables);
 		}, $this->shards);