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/**
* Copyright (C) 2015 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* 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 GNU Affero General 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 "mongo/db/namespace_string.h"
#include "mongo/db/operation_context.h"
#include "mongo/db/query/tailable_mode.h"
#include "mongo/s/client/shard.h"
namespace mongo {
class BSONObj;
class ClusterCursorManager;
class RemoteCursor;
template <typename T>
class StatusWith;
struct HostAndPort;
namespace executor {
class TaskExecutor;
} // namespace executor
/**
* Utility function to create a cursor based on existing cursor on a remote instance. 'cmdResult'
* must be the response object generated upon creation of the cursor. The newly created cursor will
* use 'executor' to retrieve batches of results from the shards and is stored with 'cursorManager'.
*
* 'requestedNss' is used to store the ClusterClientCursor for future lookup. It is also the
* namespace represented in the cursor response for the returned BSONObj. For views 'requestedNss'
* may be different then the underlying collection namespace.
*
* If 'cmdResult' does not describe a command cursor response document or no cursor is specified,
* returns 'cmdResult'. If a parsing error occurs, returns an error Status. Otherwise, returns a
* BSONObj response document describing the newly-created cursor, which is suitable for returning to
* the client.
*
* @ shardId the name of the shard on which the cursor-establishing command was run
* @ server the exact host in the shard on which the cursor-establishing command was run
* @ cmdResult the result of running the cursor-establishing command
* @ requestedNss the namespace on which the client issued the cursor-establishing command (can
* differ from the execution namespace if the command was issued on a view)
* @ executor the TaskExecutor to store in the resulting ClusterClientCursor
* @ cursorManager the ClusterCursorManager on which to register the resulting ClusterClientCursor
*/
StatusWith<BSONObj> storePossibleCursor(OperationContext* opCtx,
const ShardId& shardId,
const HostAndPort& server,
const BSONObj& cmdResult,
const NamespaceString& requestedNss,
executor::TaskExecutor* executor,
ClusterCursorManager* cursorManager,
TailableModeEnum tailableMode = TailableModeEnum::kNormal);
/**
* Convenience function which extracts all necessary information from the passed RemoteCursor, and
* stores a ClusterClientCursor based on it.
*/
StatusWith<BSONObj> storePossibleCursor(OperationContext* opCtx,
const NamespaceString& requestedNss,
const RemoteCursor& remoteCursor,
TailableModeEnum tailableMode);
/**
* Convenience function which extracts all necessary information from the passed CommandResponse,
* and stores a ClusterClientCursor based on it.
*/
StatusWith<BSONObj> storePossibleCursor(OperationContext* opCtx,
const NamespaceString& requestedNss,
const ShardId& shardId,
const Shard::CommandResponse& commandResponse,
TailableModeEnum tailableMode);
} // namespace mongo
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