runWithBegin<T> static method

Future<T> runWithBegin<T>(TransactionHandle? beginFn(), Future<T> action(TransactionHandle txn))

Runs action inside a fresh transaction obtained from beginFn.

On normal completion the transaction is committed. On an error, rollback is attempted only while the handle remains active; a concurrent native operation can keep it busy, so cleanup is not guaranteed. The original error is rethrown even if that rollback attempt fails.

beginFn is whatever piece of API returns a TransactionHandle? (e.g. NativeOdbcConnection.beginTransactionHandle).

Implementation

static Future<T> runWithBegin<T>(
  TransactionHandle? Function() beginFn,
  Future<T> Function(TransactionHandle txn) action,
) async {
  final txn = beginFn();
  if (txn == null) {
    throw StateError('beginTransactionHandle returned null');
  }
  try {
    final result = await action(txn);
    if (!txn.commit()) {
      throw StateError('Failed to commit transaction ${txn.txnId}');
    }
    return result;
  } on Object {
    if (txn.isActive) {
      txn.rollback();
    }
    rethrow;
  }
}