7d94878860
Reviewers: teon.banek, mferencevic, ipaljak Reviewed By: ipaljak Subscribers: pullbot Differential Revision: https://phabricator.memgraph.io/D1331
75 lines
1.8 KiB
C++
75 lines
1.8 KiB
C++
#pragma once
|
|
|
|
#include <experimental/filesystem>
|
|
#include <experimental/optional>
|
|
#include <string>
|
|
|
|
#include <rocksdb/db.h>
|
|
#include <rocksdb/options.h>
|
|
|
|
#include "utils/exceptions.hpp"
|
|
|
|
namespace storage {
|
|
|
|
namespace fs = std::experimental::filesystem;
|
|
|
|
class KVStoreError : public utils::BasicException {
|
|
public:
|
|
using utils::BasicException::BasicException;
|
|
};
|
|
|
|
/**
|
|
* Abstraction used to manage key-value pairs. The underlying implementation
|
|
* guarantees thread safety and durability properties.
|
|
*/
|
|
class KVStore final {
|
|
public:
|
|
/**
|
|
* @param storage Path to a directory where the data is persisted.
|
|
*
|
|
* NOTE: Don't instantiate more instances of a KVStore with the same
|
|
* storage directory because that will lead to undefined behaviour.
|
|
*/
|
|
explicit KVStore(fs::path storage);
|
|
|
|
/**
|
|
* Store value under the given key.
|
|
*
|
|
* @param key
|
|
* @param value
|
|
*
|
|
* @return true if the value has been successfully stored.
|
|
* In case of any error false is going to be returned.
|
|
*/
|
|
bool Put(const std::string &key, const std::string &value);
|
|
|
|
/**
|
|
* Retrieve value for the given key.
|
|
*
|
|
* @param key
|
|
*
|
|
* @return Value for the given key. std::nullopt in case of any error
|
|
* OR the value doesn't exist.
|
|
*/
|
|
std::experimental::optional<std::string> Get(const std::string &key) const
|
|
noexcept;
|
|
|
|
/**
|
|
* Delete value under the given key.
|
|
*
|
|
* @param key
|
|
*
|
|
* @return True on success, false on error. The return value is
|
|
* true if the key doesn't exist and underlying storage
|
|
* didn't encounter any error.
|
|
*/
|
|
bool Delete(const std::string &key);
|
|
|
|
private:
|
|
fs::path storage_;
|
|
std::unique_ptr<rocksdb::DB> db_;
|
|
rocksdb::Options options_;
|
|
};
|
|
|
|
} // namespace storage
|