Transport options set on the client builder drop SafeResponseConsumer #1354

Java API client version

main (f920563)

Java version

21

Elasticsearch Version

Any (client-side)

Problem description

RestClientOptions.of() and Rest5ClientOptions.of() convert other TransportOptions implementations starting from RequestOptions.DEFAULT, while initialOptions() starts from SafeResponseConsumer.DEFAULT_REQUEST_OPTIONS. Converted options therefore lose SafeResponseConsumer.

The ElasticsearchClient.of(...) builder methods transportOptions(fn) and retryConfig(...) produce DefaultTransportOptions, so a client configured like this runs without the safe consumer:

ElasticsearchClient client = ElasticsearchClient.of(b -> b
    .host("http://localhost:9200")
    .transportOptions(o -> o.addHeader("Foo", "bar"))
);

Rest5ClientOptions options = (Rest5ClientOptions) client._transportOptions();
// Expected: SafeResponseConsumer.DEFAULT_FACTORY
// Actual:   HttpAsyncResponseConsumerFactory$BasicAsyncResponseConsumerFactory
System.out.println(options.restClientRequestOptions().getHttpAsyncResponseConsumerFactory());

The legacy transport (useLegacyTransport(true)) shows the same behavior with HeapBufferedResponseConsumerFactory. An Error thrown while consuming a response can then stop the I/O reactor, the failure that SafeResponseConsumer prevents (#1046).