communication_protocol_action.h

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/* Copyright (c) 2018, 2025, Oracle and/or its affiliates.
 
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   it under the terms of the GNU General Public License, version 2.0,
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#ifndef COMMUNICATION_PROTOCOL_ACTION_INCLUDED
#define COMMUNICATION_PROTOCOL_ACTION_INCLUDED
 
#include <future>
#include "plugin/group_replication/include/group_actions/group_action.h"
#include "plugin/group_replication/include/mysql_version_gcs_protocol_map.h"
#include "plugin/group_replication/include/plugin_handlers/stage_monitor_handler.h"
#include "plugin/group_replication/include/plugin_messages/group_action_message.h"
#include "plugin/group_replication/libmysqlgcs/include/mysql/gcs/gcs_communication_interface.h"
 
/**
  Action that changes the GCS protocol version in use by the group.
 
  Note that this action's logic is actually done in process_action_message
  instead of execute_action. This is because process_action_message is executed
  in the same logical instant on all group members (in the GCS thread) while
  execute_action is executed nondeterministically on its own thread.
*/
class Communication_protocol_action final : public Group_action {
 public:
  Communication_protocol_action();
  explicit Communication_protocol_action(Gcs_protocol_version gcs_protocol);
  ~Communication_protocol_action() final;
 
  // Group_action implementation
  void get_action_message(Group_action_message **message) final;
  int process_action_message(Group_action_message &message,
                             const std::string &message_origin) final;
  enum_action_execution_result execute_action(
      bool invoking_member, Plugin_stage_monitor_handler *stage_handler,
      Notification_context *) final;
  bool stop_action_execution(bool killed) final;
  Group_action_diagnostics *get_execution_info() final;
 
 private:
  int set_consensus_leaders() const;
 
  /** Stores textual information about the action's execution. */
  Group_action_diagnostics m_diagnostics;
 
  /** The GCS protocol to change to. */
  Gcs_protocol_version m_gcs_protocol;
 
  /**
   * Future on which to wait for the protocol change to finish in the local
   * node.
   */
  std::future<void> m_protocol_change_done;
};
 
#endif /* COMMUNICATION_PROTOCOL_ACTION_INCLUDED */