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package io.scalecube.examples;

import io.scalecube.cluster.Cluster;
import io.scalecube.cluster.ClusterImpl;
import io.scalecube.cluster.ClusterMessageHandler;
import io.scalecube.cluster.transport.api.Message;
import reactor.core.publisher.Flux;

/**
 * Basic example for member transport between cluster members to run the example Start ClusterNodeA
 * and cluster ClusterNodeB A listen on transport messages B send message to member A.
 *
 * @author ronen hamias, Anton Kharenko
 */
public class MessagingExample {

  /** Main method. */
  public static void main(String[] args) throws Exception {
    // Start cluster node Alice to listen and respond for incoming greeting messages
    Cluster alice =
        new ClusterImpl()
            .handler(
                cluster -> {
                  return new ClusterMessageHandler() {
                    @Override
                    public void onMessage(Message msg) {
                      System.out.println("Alice received: " + msg.data());
                      cluster
                          .send(msg.sender(), Message.fromData("Greetings from Alice"))
                          .subscribe(null, Throwable::printStackTrace);
                    }
                  };
                })
            .startAwait();

    // Join cluster node Bob to cluster with Alice, listen and respond for incoming greeting
    // messages
    Cluster bob =
        new ClusterImpl()
            .membership(opts -> opts.seedMembers(alice.address()))
            .handler(
                cluster -> {
                  return new ClusterMessageHandler() {
                    @Override
                    public void onMessage(Message msg) {
                      System.out.println("Bob received: " + msg.data());
                      cluster
                          .send(msg.sender(), Message.fromData("Greetings from Bob"))
                          .subscribe(null, Throwable::printStackTrace);
                    }
                  };
                })
            .startAwait();

    // Join cluster node Carol to cluster with Alice and Bob
    Cluster carol =
        new ClusterImpl()
            .membership(opts -> opts.seedMembers(alice.address(), bob.address()))
            .handler(
                cluster -> {
                  return new ClusterMessageHandler() {
                    @Override
                    public void onMessage(Message msg) {
                      System.out.println("Carol received: " + msg.data());
                    }
                  };
                })
            .startAwait();

    // Send from Carol greeting message to all other cluster members (which is Alice and Bob)
    Message greetingMsg = Message.fromData("Greetings from Carol");

    Flux.fromIterable(carol.otherMembers())
        .flatMap(member -> carol.send(member, greetingMsg))
        .subscribe(null, Throwable::printStackTrace);

    // Avoid exit main thread immediately ]:->
    Thread.sleep(1000);
  }
}