/**
* Create a Transaction
*
* Example:
* ```
* $transaction = $datastore->transaction();
* ```
*
* @see https://cloud.google.com/datastore/docs/concepts/transactions Datastore Transactions
*
* @param array $options [optional] Configuration options.
* @return Transaction
*/
public function transaction(array $options = [])
{
$res = $this->connection->beginTransaction($options + ['projectId' => $this->projectId]);
return new Transaction(clone $this->operation, $this->projectId, $res['transaction']);
}
