Method maybeStorePreparedMetadata

proxy/proxy.go:952–979

maybeStorePreparedMetadata stores the idempotence of a "PREPARE" request's query. This information is used by future "EXECUTE" requests when they need to be retried.

(raw *frame.RawFrame, isSelect bool, msg message.Message)

// maybeStorePreparedMetadata stores the idempotence of a "PREPARE" request's query.
// This information is used by future "EXECUTE" requests when they need to be retried.
func (c *client) maybeStorePreparedMetadata(raw *frame.RawFrame, isSelect bool, msg message.Message) {
	logger := c.proxy.logger

	if prepareMsg, ok := msg.(*message.Prepare); ok && raw.Header.OpCode == primitive.OpCodeResult { // Prepared result
		frm, err := c.codec.ConvertFromRawFrame(raw)
		if err != nil {
			logger.Error("error attempting to decode prepared result message")
		} else if preparedResultMsg, ok := frm.Body.Message.(*message.PreparedResult); !ok { // TODO: Use prepared type data to disambiguate idempotency
			logger.Error("expected prepared result message, but got something else")
		} else {
			logger.Debug("prepared request",
				zap.Stringer("request", prepareMsg),
				zap.Stringer("response", preparedResultMsg))
			idempotent, err := parser.IsQueryIdempotent(prepareMsg.Query)
			if err != nil {
				logger.Error("error parsing query for idempotence", zap.Error(err))
			} else if result, ok := frm.Body.Message.(*message.PreparedResult); ok {
				c.proxy.preparedMetadata.Store(preparedIdKey(result.PreparedQueryId), preparedMetadata{
					idempotent: idempotent,
					isSelect:   isSelect,
				})
			} else {
				logger.Error("expected prepared result, but got some other type of message",
					zap.Stringer("type", reflect.TypeOf(frm.Body.Message)))
			}
		}
	}
}

func getOrCreateDefaultPreparedCache(cache proxycore.PreparedCache) (proxycore.PreparedCache, error) {
	if cache == nil {