@assafcoh duplicate of #257?

@owaiskazi19 this issue is a "general" request for supporting creation of all API objects from JSON.
The CreateIndexRequest code I mentioned above is just one example for one API.

Specifically, on our project, we are mostly interested in being able to create queries from JSON, something like below:

Reader queryJson = new StringReader(
    "{" +
    "  \"query\": {" +
    "    \"range\": {" +
    "      \"@timestamp\": {" +
    "        \"gt\": \"now-1w\"" +
    "      }" +
    "    }" +
    "  }," +
    "  \"size\": 100" + ,
    "  \"aggregations\": {" +
    "    \"hours\": {" +
    "      \"date_histogram\": {" +
    "        \"field\": \"@timestamp\"," +
    "        \"interval\": \"hour\"" +
    "      }," +
    "      \"aggregations\": {" +
    "        \"max-cpu\": {" +
    "          \"max\": {" +
    "            \"field\": \"host.cpu.usage\"" +
    "          }" +
    "        }" +
    "      }" +
    "    }" +
    "  }" +
    "}");

SearchRequest aggRequest = SearchRequest.of(b -> b
    .withJson(queryJson) 
);

Map<String, Aggregate> aggs = client
    .search(aggRequest, Void.class)
    .aggregations();

This sounds like a good idea. Feel free to create a PR.

The functionality proposed here would be quite helpful.

As @assafcoh pointed out, it would be a "general" solution. It would also apply to more special feature requests such as asking for custom JSON input for mapping information (#362) or for documents (#257).

There is something like that in the Elastic Java client. For example the builders of TypeMapping and IndexSettings implement the interface WithJson.

That allows for code such as the following:

InputStream mapping = /* ... */;
InputStream settings = /* ... */;
CreateIndexRequest req =
    CreateIndexRequest.of(
        cir ->
            cir.index(INDEX_NAME)
                .mappings(m -> m.withJson(mapping))
                .settings(s -> s.withJson(settings)));

As that client is licensed under the Apache 2.0 license, it should be possible to reuse that (or a similar) approach also for the OpenSearch Java client.

As that client is licensed under the Apache 2.0 license, it should be possible to reuse that (or a similar) approach also for the OpenSearch Java client.

Please feel free to contribute! When making PRs we trust you to make sure you're not copying any non-APLv2 code.