foundationdb/fdbserver/OnDemandStore.h

49 lines
1.4 KiB
C++

/*
* OnDemandStore.h
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2022 Apple Inc. and the FoundationDB project authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include "flow/Arena.h"
#include "flow/IRandom.h"
#include "flow/Platform.h"
#include "fdbserver/IKeyValueStore.h"
// Create a key value store if and only if it is actually used
class OnDemandStore : public IClosable, NonCopyable {
std::string folder;
UID myID;
IKeyValueStore* store;
Promise<Future<Void>> err;
std::string prefix;
void open();
public:
OnDemandStore(std::string const& folder, UID myID, std::string const& prefix);
~OnDemandStore();
IKeyValueStore* get();
bool exists() const;
IKeyValueStore* operator->();
Future<Void> getError() const override;
Future<Void> onClosed() const override;
void dispose() override;
void close() override;
};