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/**
* Copyright (C) 2010-2015 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 <string>
#include <vector>
#include "mongo/s/catalog/forwarding_catalog_manager.h"
#include "mongo/s/query/cluster_cursor_manager.h"
#include "mongo/stdx/memory.h"
namespace mongo {
class BSONObj;
class CatalogCache;
class DBConfig;
class OperationContext;
class SettingsType;
class ShardRegistry;
template <typename T>
class StatusWith;
/**
* Holds the global sharding context. Single instance exists for a running server. Exists on
* both MongoD and MongoS.
*/
class Grid {
public:
Grid();
/**
* Called at startup time so the global sharding services can be set. This method must be called
* once and once only for the lifetime of the service.
*
* NOTE: Unit-tests are allowed to call it more than once, provided they reset the object's
* state using clearForUnitTests.
*/
void init(std::unique_ptr<ForwardingCatalogManager> catalogManager,
std::unique_ptr<ShardRegistry> shardRegistry,
std::unique_ptr<ClusterCursorManager> cursorManager);
/**
* Implicitly creates the specified database as non-sharded.
*/
StatusWith<std::shared_ptr<DBConfig>> implicitCreateDb(OperationContext* txn,
const std::string& dbName);
/**
* @return true if shards and config servers are allowed to use 'localhost' in address
*/
bool allowLocalHost() const;
/**
* @param whether to allow shards and config servers to use 'localhost' in address
*/
void setAllowLocalHost(bool allow);
/**
* Returns true if the balancer should be running. Caller is responsible
* for making sure settings has the balancer key.
*/
bool shouldBalance(const SettingsType& balancerSettings) const;
/**
* Returns true if the config server settings indicate that the balancer should be active.
*/
bool getConfigShouldBalance(OperationContext* txn) const;
/**
* Returns a pointer to a CatalogManager to use for accessing catalog data stored on the config
* servers.
*/
CatalogManager* catalogManager(OperationContext* txn);
/**
* Returns a direct pointer to the ForwardingCatalogManager. This should only be used for
* calling methods that are specific to the ForwardingCatalogManager and not part of the generic
* CatalogManager interface, such as for taking the distributed lock and scheduling replacement
* of the underlying CatalogManager that the ForwardingCatalogManager is delegating to.
*/
ForwardingCatalogManager* forwardingCatalogManager();
CatalogCache* catalogCache() {
return _catalogCache.get();
}
ShardRegistry* shardRegistry() {
return _shardRegistry.get();
}
ClusterCursorManager* getCursorManager() {
return _cursorManager.get();
}
/**
* Clears the grid object so that it can be reused between test executions. This will not
* be necessary if grid is hanging off the global ServiceContext and each test gets its
* own service context.
*
* NOTE: Do not use this outside of unit-tests.
*/
void clearForUnitTests();
private:
std::unique_ptr<ForwardingCatalogManager> _catalogManager;
std::unique_ptr<CatalogCache> _catalogCache;
std::unique_ptr<ShardRegistry> _shardRegistry;
std::unique_ptr<ClusterCursorManager> _cursorManager;
// can 'localhost' be used in shard addresses?
bool _allowLocalShard;
};
extern Grid grid;
} // namespace mongo
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