@Override
    public void onFailure(
            ActionRequest action, Throwable failure, int restStatusCode, RequestIndexer indexer) {
        // ignore failure
    }
Ignores all kinds of failures and drops the affected {@link ActionRequest}.
inlong-sort/sort-flink/sort-flink-v1.15/sort-connectors/elasticsearch-base/src/main/java/org/apache/inlong/sort/elasticsearch/util/IgnoringFailureHandler.java