private void requestBinlogSplitMetaIfNeeded(MySqlBinlogSplit binlogSplit) {
        final String splitId = binlogSplit.splitId();
        if (!binlogSplit.isCompletedSplit()) {
            final int nextMetaGroupId =
                    getNextMetaGroupId(
                            binlogSplit.getFinishedSnapshotSplitInfos().size(),
                            sourceConfig.getSplitMetaGroupSize());
            BinlogSplitMetaRequestEvent splitMetaRequestEvent =
                    new BinlogSplitMetaRequestEvent(splitId, nextMetaGroupId);
            context.sendSourceEventToCoordinator(splitMetaRequestEvent);
        } else {
            LOG.info("The meta of binlog split {} has been collected success", splitId);
            this.addSplits(Collections.singletonList(binlogSplit));
        }
    }
The source reader for MySQL source splits.
copy from {@link com.ververica.cdc.connectors.mysql.source.reader.MySqlSourceReader}
inlong-sort/sort-flink/sort-flink-v1.15/sort-connectors/mysql-cdc/src/main/java/org/apache/inlong/sort/mysql/source/reader/MySqlSourceReader.java