group_validation_message.h

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/* Copyright (c) 2018, 2024, Oracle and/or its affiliates.
 
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   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.
 
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.
 
   You should have received a copy of the GNU General Public License
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   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
 
#ifndef GROUP_VALIDATION_MESSAGE_INCLUDED
#define GROUP_VALIDATION_MESSAGE_INCLUDED
 
#include "my_inttypes.h"
#include "plugin/group_replication/include/gcs_plugin_messages.h"
 
/** The base message for group validation messages */
class Group_validation_message : public Plugin_gcs_message {
 public:
  /** Enum for message payload */
  enum enum_payload_item_type {
    PIT_UNKNOWN = 0,             // Not used
    PIT_VALIDATION_TYPE = 1,     // The validation type, length: 2 bytes
    PIT_VALIDATION_CHANNEL = 2,  // The member has channel flag, length: 1 bytes
    PIT_MEMBER_WEIGHT = 3,       // The member weight, length: 2 bytes
    PIT_SENT_TIMESTAMP = 4,      // Length: 8 bytes
    PIT_MAX  // No valid type codes can appear after this one
  };
 
  /** Enum for the types of validation action **/
  enum enum_validation_message_type {
    GROUP_VALIDATION_UNKNOWN_MESSAGE = 0,  // Reserved type
    ELECTION_VALIDATION_MESSAGE = 1,       // Member info for elections
    GROUP_VALIDATION_MESSAGE_END = 2       // Enum end value
  };
 
  /**
    Class constructor
    @param has_channels This member has running slave channels?
    @param member_weight_arg The election weight of this member
  */
  Group_validation_message(bool has_channels, uint member_weight_arg);
 
  /**
    Message constructor for raw data
 
    @param[in] buf raw data
    @param[in] len raw length
  */
  Group_validation_message(const uchar *buf, size_t len);
 
  /** Class destructor */
  ~Group_validation_message() override;
 
  /**
    Does the member has running channels
    @return true if yes, false otherwise
  */
  bool has_slave_channels() const;
 
  /**
    The election weight of this member
    @return The member weight
  */
  uint get_member_weight() const;
 
  /**
    Return the time at which the message contained in the buffer was sent.
    @see Metrics_handler::get_current_time()
 
    @param[in] buffer            the buffer to decode from.
    @param[in] length            the buffer length
 
    @return the time on which the message was sent.
  */
  static uint64_t get_sent_timestamp(const unsigned char *buffer,
                                     size_t length);
 
 protected:
  /**
    Encodes the message contents for transmission.
 
    @param[out] buffer   the message buffer to be written
  */
  void encode_payload(std::vector<unsigned char> *buffer) const override;
 
  /**
    Message decoding method
 
    @param[in] buffer the received data
  */
  void decode_payload(const unsigned char *buffer,
                      const unsigned char *) override;
 
 private:
  /**The message type*/
  enum_validation_message_type group_validation_message_type;
 
  /** Does the member has channels? */
  bool has_channels;
 
  /** The member election weight */
  uint member_weight;
};
 
#endif /* GROUP_VALIDATION_MESSAGE_INCLUDED */