Transaction.php

<?php

namespace Drupal\Core\Database;


/**
 * A wrapper class for creating and managing database transactions.
 *
 * To begin a transaction, simply start it. When the object goes out of scope
 * and is destroyed it will automatically commit.
 *
 * In the vast majority of cases, you should not instantiate this class
 * directly. Instead, call ->startTransaction(), from the appropriate connection
 * object.
 *
 * @see \Drupal\Core\Database\Connection::startTransaction()
 */
class Transaction {
    public function __construct(Connection $connection, string $name, string $id) {
        // Transactions rely on objects being destroyed in order to be committed.
        // PHP makes no guarantee about the order in which objects are destroyed so
        // ensure all transactions are committed on shutdown.
        Database::commitAllOnShutdown();
    }
    
    /**
     * Destructs the object.
     *
     * Depending on the nesting level of the object, this leads to a COMMIT (for
     * a root item) or to a RELEASE SAVEPOINT (for a savepoint item) executed on
     * the database.
     */
    public function __destruct() {
        $this->connection
            ->transactionManager()
            ->unpile($this->name, $this->id);
    }
    
    /**
     * Retrieves the name of the transaction or savepoint.
     */
    public function name() {
        return $this->name;
    }
    
    /**
     * Rolls back the current transaction.
     *
     * This is just a wrapper method to rollback whatever transaction stack we are
     * currently in, which is managed by the TransactionManager. Note that logging
     * needs to happen after a transaction has been rolled back or the log
     * messages will be rolled back too.
     *
     * Depending on the nesting level of the object, this leads to a ROLLBACK (for
     * a root item) or to a ROLLBACK TO SAVEPOINT (for a savepoint item) executed
     * on the database.
     */
    public function rollBack() {
        $this->connection
            ->transactionManager()
            ->rollback($this->name, $this->id);
    }

}