Disable timeout params for deleteIndex API only for serverless

[ykmr1224]

Description

• Disable timeout params for deleteIndex API only for serverless
• OpenSearch serverless does not accept timeout / master_timeout (= clusterManagerNodeTimeout) params, which is added by the RestHighLevelClient by default. (current version of opensearch-java library won't add it automatically, but we are still using 2.6.0 (ref)

Issues Resolved

#634

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[noCharger]

non-blocking: can we handle this in RestHighLevelClientWrapper and consider use DeleteIndexRequestBuilder?

[ykmr1224]

non-blocking: can we handle this in RestHighLevelClientWrapper and consider use DeleteIndexRequestBuilder?

RestHighLevelClientWrapper does not have reference to FlintOptions.
What do you mean by DeleteIndexRequestBuilder?

[noCharger]

non-blocking: can we handle this in RestHighLevelClientWrapper and consider use DeleteIndexRequestBuilder?

RestHighLevelClientWrapper does not have reference to FlintOptions. What do you mean by DeleteIndexRequestBuilder?

Example:

public void deleteIndex(String indexName) {
    LOG.info("Deleting Flint index " + indexName);
    String osIndexName = sanitizeIndexName(indexName);
    try (IRestHighLevelClient client = createClient()) {
        DeleteIndexRequest request = buildDeleteIndexRequest(osIndexName);
        client.indices().delete(request, RequestOptions.DEFAULT);
    } catch (Exception e) {
        throw new IllegalStateException("Failed to delete Flint index " + osIndexName, e);
    }
}

private DeleteIndexRequest buildDeleteIndexRequest(String indexName) {
    DeleteIndexRequestBuilder builder = new DeleteIndexRequestBuilder(indexName);

    if (FlintOptions.SERVICE_NAME_AOSS.equals(options.getServiceName())) {
        // Disable timeouts for serverless environments
        builder.setClusterManagerNodeTimeout((TimeValue) null)
               .setTimeout((TimeValue) null);
    }

    return builder.build();
}

[seankao-az]

lgtm
+1 on Louis' idea on moving new DeleteIndexRequest(osIndexName) into build method.
but don't think it's necessary

[ykmr1224]

I think current approach is more explicit and easier to read, though there could be some preference.
btw, DeleteIndexRequestBuilder does not look like usable considering the constructor signature: public DeleteIndexRequestBuilder(OpenSearchClient client, DeleteIndexAction action, String... indices)

[noCharger]

I think current approach is more explicit and easier to read, though there could be some preference. btw, DeleteIndexRequestBuilder does not look like usable considering the constructor signature: public DeleteIndexRequestBuilder(OpenSearchClient client, DeleteIndexAction action, String... indices)

Actually, the DeleteIndexRequestBuilder from the library does not appear to be for external use; using the builder pattern externally is possible by extending it, but it is fine to leave it as is.