in flink-connector-opensearch/src/main/java/org/apache/flink/connector/opensearch/sink/OpensearchWriter.java [130:136]
public void write(IN element, Context context) throws IOException, InterruptedException {
// do not allow new bulk writes until all actions are flushed
while (checkpointInProgress) {
mailboxExecutor.yield();
}
emitter.emit(element, context, requestIndexer);
}