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/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <memory>
#include "mongo/base/disallow_copying.h"
#include "mongo/db/logical_session_id.h"
#include "mongo/db/transaction_coordinator_catalog.h"
#include "mongo/util/future.h"
namespace mongo {
class ShardId;
class OperationContext;
class ServiceContext;
class TransactionCoordinatorService final {
MONGO_DISALLOW_COPYING(TransactionCoordinatorService);
public:
TransactionCoordinatorService();
~TransactionCoordinatorService() = default;
/**
* Retrieves the TransactionCoordinatorService associated with the service or operation context.
*/
static TransactionCoordinatorService* get(OperationContext* opCtx);
static TransactionCoordinatorService* get(ServiceContext* serviceContext);
/**
* Creates a new TransactionCoordinator for the given session id and transaction number, with a
* deadline for the commit decision. If the coordinator has not decided to commit by that
* deadline, it will abort.
*/
void createCoordinator(OperationContext* opCtx,
LogicalSessionId lsid,
TxnNumber txnNumber,
Date_t commitDeadline);
/**
* If a coordinator for the (lsid, txnNumber) exists, delivers the participant list to the
* coordinator, which will cause the coordinator to start coordinating the commit if the
* coordinator had not yet received a list, and returns a Future that will contain the decision
* when the transaction finishes committing or aborting.
*
* If no coordinator for the (lsid, txnNumber) exists, returns boost::none.
*/
boost::optional<Future<txn::CommitDecision>> coordinateCommit(
OperationContext* opCtx,
LogicalSessionId lsid,
TxnNumber txnNumber,
const std::set<ShardId>& participantList);
/**
* If a coordinator for the (lsid, txnNumber) exists, returns a Future that will contain the
* decision when the transaction finishes committing or aborting.
*
* If no coordinator for the (lsid, txnNumber) exists, returns boost::none.
*/
boost::optional<Future<txn::CommitDecision>> recoverCommit(OperationContext* opCtx,
LogicalSessionId lsid,
TxnNumber txnNumber);
/**
* Marks the coordinator catalog as stepping up, which blocks all incoming requests for
* coordinators, and launches an async task to:
* 1. Wait for the coordinators in the catalog to complete (successfully or with an error) and
* be removed from the catalog.
* 2. Read all pending commit tasks from the config.transactionCoordinators collection.
* 3. Create TransactionCoordinator objects in memory for each pending commit and launch an
* async task to continue coordinating its commit.
*/
void onStepUp(OperationContext* opCtx);
void onStepDown(OperationContext* opCtx);
private:
std::shared_ptr<TransactionCoordinatorCatalog> _coordinatorCatalog;
};
} // namespace mongo
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