Discovery v5 by Dmitrii Shmatko

Who am I?

Dmitrii Shmatko from Harmony team
Last 5 years: Java, Ethereum, Python, Node.js, Financial apps
Before: small IT enterprenuer, development management, databases

Specification

What's node ID?

Module first!

Module structure

Client/Server

 /** 
 * Netty-specific extension of {@link DiscoveryServer}. 
 * Made to reuse server channel for client. 
 */
public interface NettyDiscoveryServer extends DiscoveryServer {
 
  /** 
   * Reuse Netty server channel with client, 
   * so you are able to send packets from the same port 
   */
  CompletableFuture<Void> useDatagramChannel(
      Consumer<NioDatagramChannel> consumer);
}

Data flow

Pipeline setup:

     incomingPipeline
        .addHandler(new IncomingDataPacker())
        .addHandler(new WhoAreYouAttempt(homeNode.getNodeId()))
        .addHandler(new WhoAreYouSessionResolver(authTagRepo))
        .addHandler(new UnknownPacketTagToSender(homeNode))
        .addHandler(nodeIdToSession)
        .addHandler(new UnknownPacketTypeByStatus())
        .addHandler(new NotExpectedIncomingPacketHandler())
        .addHandler(new WhoAreYouPacketHandler(outgoingPipeline, taskScheduler))

start:

     incomingPipeline.build();
    Flux.from(discoveryServer.getIncomingPackets())
    .subscribe(incomingPipeline::push);

Handler

Outgoing pipeline

setup:

     outgoingPipeline
        .addHandler(new OutgoingParcelHandler(outgoingSink))
        .addHandler(new NodeSessionRequestHandler())
        .addHandler(nodeIdToSession)
        .addHandler(new NewTaskHandler())
        .addHandler(new NextTaskHandler(outgoingPipeline, taskScheduler));

usage:

   public void sendOutgoing(Packet packet) {
    logger.trace(() -> String.format("Sending outgoing packet %s in session %s", packet, this));
    outgoing.accept(packet);
  }

Discovery v5

..

Who am I?

Specification

Module first!

Module structure

Client/Server

Data flow

Handler

Outgoing pipeline

ENR

ENR Specification

NodeSession

Discovery Manager

Tests

Interop test

Plans

Thank you!

Questions ?!

	/**
	* Netty-specific extension of {@link DiscoveryServer}.
	* Made to reuse server channel for client.
	*/
	public interface NettyDiscoveryServer extends DiscoveryServer {

	/**
	* Reuse Netty server channel with client,
	* so you are able to send packets from the same port
	*/
	CompletableFuture<Void> useDatagramChannel(
	Consumer<NioDatagramChannel> consumer);
	}

	incomingPipeline
	.addHandler(new IncomingDataPacker())
	.addHandler(new WhoAreYouAttempt(homeNode.getNodeId()))
	.addHandler(new WhoAreYouSessionResolver(authTagRepo))
	.addHandler(new UnknownPacketTagToSender(homeNode))
	.addHandler(nodeIdToSession)
	.addHandler(new UnknownPacketTypeByStatus())
	.addHandler(new NotExpectedIncomingPacketHandler())
	.addHandler(new WhoAreYouPacketHandler(outgoingPipeline, taskScheduler))

	incomingPipeline.build();
	Flux.from(discoveryServer.getIncomingPackets())
	.subscribe(incomingPipeline::push);

	outgoingPipeline
	.addHandler(new OutgoingParcelHandler(outgoingSink))
	.addHandler(new NodeSessionRequestHandler())
	.addHandler(nodeIdToSession)
	.addHandler(new NewTaskHandler())
	.addHandler(new NextTaskHandler(outgoingPipeline, taskScheduler));

	public void sendOutgoing(Packet packet) {
	logger.trace(() -> String.format("Sending outgoing packet %s in session %s", packet, this));
	outgoing.accept(packet);
	}