Transport layer

Elastic.Ingest.Transport bridges the buffered channel infrastructure with Elastic.Transport (ITransport). It provides the base class TransportChannelBase and the options base TransportChannelOptionsBase.

TransportChannelBase passes the ITransport instance from options to the ExportAsync method, so subclasses can make HTTP calls without managing transport lifecycle.

// Subclass implements:
protected abstract Task<TResponse> ExportAsync(
    ITransport transport,
    ArraySegment<TEvent> items,
    CancellationToken ctx
);
		

In IngestChannelBase, this builds a _bulk request from the items array and sends it through the transport.

The transport is provided through channel options:

var transport = new DistributedTransport(
    new TransportConfiguration(new Uri("http://localhost:9200"))
);

var options = new IngestChannelOptions<MyDoc>(transport, MyContext.MyDoc.Context);
		

Transport configuration (timeouts, authentication, connection pooling) is handled by Elastic.Transport -- the channel inherits whatever is configured on the transport instance.

TransportChannelBase overrides the drain timeout to use the transport's RequestTimeout. This means drain calculations account for how long each bulk request might take, rather than using an arbitrary default.

Strategies and orchestrators use the transport directly for non-bulk operations (template creation, alias management, rollover). Common patterns:

// PUT with body
await transport.PutAsync<StringResponse>(url, PostData.String(body), cancellationToken: ctx);

// HEAD check (exists?)
var head = await transport.HeadAsync(url, ctx);
if (head.ApiCallDetails.HttpStatusCode == 200) { /* exists */ }

// GET with response
var response = await transport.GetAsync<StringResponse>(url, ctx);
		

See custom strategies for examples of using the transport in your own strategy implementations.