Method readPayloadImpl

src/Core/MySQL/MySQLReplication.cpp:920–1062

    }
    
    void MySQLFlavor::readPayloadImpl(ReadBuffer & payload)
    {
        if (payload.eof())
            throw Exception("Attempt to read after EOF.", ErrorCodes::ATTEMPT_TO_READ_AFTER_EOF);

        UInt16 header = static_cast<unsigned char>(*payload.position());
        switch (header)
        {
            case PACKET_EOF:
                throw ReplicationError("Master maybe lost", ErrorCodes::CANNOT_READ_ALL_DATA);
            case PACKET_ERR:
                ERRPacket err;
                err.readPayloadWithUnpacked(payload);
                throw ReplicationError(err.error_message, ErrorCodes::UNKNOWN_EXCEPTION);
        }
        // skip the generic response packets header flag.
        payload.ignore(1);

        MySQLBinlogEventReadBuffer event_payload(payload, checksum_signature_length);

        EventHeader event_header;
        event_header.parse(event_payload);

        switch (event_header.type)
        {
            case FORMAT_DESCRIPTION_EVENT:
            {
                event = std::make_shared<FormatDescriptionEvent>(std::move(event_header));
                event->parseEvent(event_payload);
                position.update(event);
                break;
            }
            case ROTATE_EVENT:
            {
                event = std::make_shared<RotateEvent>(std::move(event_header));
                event->parseEvent(event_payload);
                position.update(event);
                break;
            }
            case QUERY_EVENT:
            {
                event = std::make_shared<QueryEvent>(std::move(event_header));
                event->parseEvent(event_payload);
                position.update(event);

                auto query = std::static_pointer_cast<QueryEvent>(event);
                switch (query->typ)
                {
                    case QUERY_EVENT_MULTI_TXN_FLAG:
                    case QUERY_EVENT_XA:
                    /// Ignore queries that have no impact on the data.
                    case QUERY_SAVEPOINT:
                    {
                        event = std::make_shared<DryRunEvent>(std::move(query->header));
                        break;
                    }
                    default:
                        break;