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 447c164c1a4312cf1acc6d7ab7f32cd249b84d68..3cb8ea17aedd1146c7c2c508411a65bd9d59eb38 100644 (file)
--- 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);