Automated Transaction Guard (PDO)

In persistent workers, database connections (PDO instances) are long-lived and reused across sequential requests.

If an HTTP request begins a database transaction ($pdo->beginTransaction() or DB::beginTransaction()) but fails to commit or roll back (due to an unhandled exception, early return, or developer oversight):

• The transaction remains active on the connection.
• The connection is returned to the pool or reused by the worker.
• The next user's request unintentionally runs queries inside the uncommitted transaction of the previous user.
• This leads to table lockups, concurrency deadlocks, and cross-tenant data corruption.

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How TransactionGuard Works

At the end of every request cycle ($leakless->endRequest()), the TransactionGuard engine runs an automated audit:

1. Connection Auto-Discovery:
   • In Laravel Octane, inspects DB::getConnections() to retrieve all active database connections (Illuminate\Database\Connection).
   • In Vanilla PHP, developers or containers can register PDO instances via $leakless->registerPdo($pdo).
2. Transaction State Inspection:
   • Queries $pdo->inTransaction() on every registered and discovered connection.
3. Automated Rollback:
   • If any connection has an active transaction open, TransactionGuard immediately calls $pdo->rollBack().
4. Diagnostic Logging & Reporting:
   • Logs an alert containing the count of rolled-back transactions: [Leakless] 🚨 Dangling database transaction(s) detected and rolled back (1 transaction(s)).
   • Sets hasTransactionLeak = true in the Report DTO.

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Registering Custom PDO Connections (Vanilla PHP)

In vanilla PHP or non-Laravel frameworks, register your PDO instances into Leakless:

$pdo = new PDO('mysql:host=localhost;dbname=app', 'user', 'pass');

// Register PDO connection for automated end-of-request transaction audits
$leakless->registerPdo($pdo);