Feature request to publish JsonNetSerializer

[deinman]

Is your feature request related to a problem? Please describe.

Using latest Elastic.Clients.Elasticsearch (8.15.6) and trying to serialize with the JsonNetSerializer doesn't work as indicated in the test code. You've got these great examples in the tests:

elasticsearch-net/tests/Tests/ClientConcepts/HighLevel/Serialization/CustomSerialization.doc.cs

Lines 127 to 145 in de00805

	public void DefaultJsonNetSerializer()
	{
	var pool = new SingleNodePool(new Uri("http://localhost:9200"));
	var connectionSettings =
	new ElasticsearchClientSettings(pool, sourceSerializer: JsonNetSerializer.Default);
	var client = new ElasticsearchClient(connectionSettings);
	}
	/**
	* `JsonNetSerializer.Default` is just syntactic sugar for passing a delegate like
	*/
	public void DefaultJsonNetSerializerUnsugared()
	{
	var pool = new SingleNodePool(new Uri("http://localhost:9200"));
	var connectionSettings = new ElasticsearchClientSettings(
	pool,
	sourceSerializer: (builtin, settings) => new JsonNetSerializer(builtin, settings));
	var client = new ElasticsearchClient(connectionSettings);
	}

But it looks like you're not shipping the updated JsonNetSerializer. The NEST 7.15 version is available in NuGet, but at some point there were updates made with Elastic.Clients.Elasticsearch.JsonNetSerializer that aren't exposed anywhere. And I can't work out a way to use the 7.15 version with the Elastic.Clients.ElasticSearch 8.15.* versions.

Describe the solution you'd like

Please publish the Elastic.Clients.Elasticsearch.JsonNetSerializer.

Describe alternatives you've considered

My alternative seems to be to fork the Elastic.Clients.Elasticsearch.JsonNetSerializer code and reference that internally, but that's a lot of extra overhead given your published test suite utilizes the Elastic.Clients.Elasticsearch.JsonNetSerializer code.

Additional context

I've setup a repo to demonstrate the issue here: https://github.com/deinman/demoissueelastic

[flobernd]

Hi @deinman,

bringing back the JsonNetSerializer is currently not on the roadmap. It's currently unreleased as we did not have the capacity to thoroughly test it with the new client.

The new Elasticsearch client and the underlaying Elastic.Transport library is highly customizable and should allow you to implement a custom Serializer that delegates all (de-)serialization to Json.NET.

To get you started:

ElasticsearchClientSettings has a constructor overload that accepts a SourceSerializerFactory lambda. This lambda should return a custom Elastic.Transport.Serializer implementation.

I'm keeping this issue open as a feature request, but I can't promise anything at the moment or even give an ETA.