query_execution/QueryExecutionUtil.hpp

/**
 *   Copyright 2015 Pivotal Software, Inc.
 *
 *   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.
 **/

#ifndef QUICKSTEP_QUERY_EXECUTION_QUERY_EXECUTION_UTIL_HPP_
#define QUICKSTEP_QUERY_EXECUTION_QUERY_EXECUTION_UTIL_HPP_

#include <utility>

#include "query_execution/QueryExecutionTypedefs.hpp"
#include "utility/Macros.hpp"

#include "tmb/address.h"
#include "tmb/message_style.h"
#include "tmb/message_bus.h"
#include "tmb/tagged_message.h"

namespace quickstep {

/**
 * @brief A static class for reusable methods in query_execution module.
 **/
class QueryExecutionUtil {
 public:
  /**
   * @brief Send a TMB message to a single receiver.
   *
   * @param bus A pointer to the TMB.
   * @param sender_id The client ID of the sender.
   * @param receiver_id The client ID of the receiver.
   * @param tagged_message A moved-from reference to the tagged message.
   *
   * @return A status code indicating the result of the message getting sent.
   *         The caller should ensure that the status is SendStatus::kOK.
   **/
  static tmb::MessageBus::SendStatus SendTMBMessage(
      MessageBus *bus,
      client_id sender_id,
      client_id receiver_id,
      TaggedMessage &&tagged_message) {  // NOLINT(whitespace/operators)
    Address receiver_address;
    receiver_address.AddRecipient(receiver_id);

    MessageStyle single_receiver_style;
    return bus->Send(sender_id,
                     receiver_address,
                     single_receiver_style,
                     std::move(tagged_message));
  }

 private:
  /**
   * @brief Constructor. Made private to avoid instantiation.
   **/
  QueryExecutionUtil();

  DISALLOW_COPY_AND_ASSIGN(QueryExecutionUtil);
};

/** @} */

}  // namespace quickstep

#endif  // QUICKSTEP_QUERY_EXECUTION_QUERY_EXECUTION_UTIL_HPP_