extensions/standard-processors/controllers/InMemoryKeyValueStorage.h

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 <functional>
#include <memory>
#include <string>
#include <unordered_map>
#include <utility>

#include "core/logging/Logger.h"
#include "core/logging/LoggerFactory.h"

namespace org::apache::nifi::minifi::controllers {

class InMemoryKeyValueStorage {
 public:
  InMemoryKeyValueStorage() = default;
  explicit InMemoryKeyValueStorage(std::unordered_map<std::string, std::string> contents) : map_{std::move(contents)} {}

  bool set(const std::string& key, const std::string& value);
  bool get(const std::string& key, std::string& value);
  bool get(std::unordered_map<std::string, std::string>& kvs);
  bool remove(const std::string& key);
  bool clear();
  bool update(const std::string& key, const std::function<bool(bool /*exists*/, std::string& /*value*/)>& update_func);

 private:
  std::unordered_map<std::string, std::string> map_;
  std::shared_ptr<core::logging::Logger> logger_ = core::logging::LoggerFactory<InMemoryKeyValueStorage>::getLogger();
};

}  // namespace org::apache::nifi::minifi::controllers