rocksdb/utilities/cassandra/merge_operator.h
mrambacher d057e8326d Make MergeOperator+CompactionFilter/Factory into Customizable Classes (#8481)
Summary:
- Changed MergeOperator, CompactionFilter, and CompactionFilterFactory into Customizable classes.
 - Added Options/Configurable/Object Registration for TTL and Cassandra variants
 - Changed the StringAppend MergeOperators to accept a string delimiter rather than a simple char.  Made the delimiter into a configurable option
 - Added tests for new functionality

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8481

Reviewed By: zhichao-cao

Differential Revision: D30136050

Pulled By: mrambacher

fbshipit-source-id: 271d1772835935b6773abaf018ee71e42f9491af
2021-08-06 08:27:25 -07:00

45 lines
1.6 KiB
C++

// Copyright (c) 2017-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include "rocksdb/merge_operator.h"
#include "rocksdb/slice.h"
#include "utilities/cassandra/cassandra_options.h"
namespace ROCKSDB_NAMESPACE {
namespace cassandra {
/**
* A MergeOperator for rocksdb that implements Cassandra row value merge.
*/
class CassandraValueMergeOperator : public MergeOperator {
public:
explicit CassandraValueMergeOperator(int32_t gc_grace_period_in_seconds,
size_t operands_limit = 0);
virtual bool FullMergeV2(const MergeOperationInput& merge_in,
MergeOperationOutput* merge_out) const override;
virtual bool PartialMergeMulti(const Slice& key,
const std::deque<Slice>& operand_list,
std::string* new_value,
Logger* logger) const override;
const char* Name() const override { return kClassName(); }
static const char* kClassName() { return "CassandraValueMergeOperator"; }
virtual bool AllowSingleOperand() const override { return true; }
virtual bool ShouldMerge(const std::vector<Slice>& operands) const override {
return options_.operands_limit > 0 &&
operands.size() >= options_.operands_limit;
}
private:
CassandraOptions options_;
};
} // namespace cassandra
} // namespace ROCKSDB_NAMESPACE