opendaylight/md-sal/eos-dom-akka/src/main/java/org/opendaylight/controller/eos/akka/owner/checker/OwnerStateChecker.java

   1 /*
   2  * Copyright (c) 2021 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.eos.akka.owner.checker;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import akka.actor.typed.Behavior;
  13 import akka.actor.typed.javadsl.AbstractBehavior;
  14 import akka.actor.typed.javadsl.ActorContext;
  15 import akka.actor.typed.javadsl.Behaviors;
  16 import akka.actor.typed.javadsl.Receive;
  17 import akka.cluster.ddata.LWWRegister;
  18 import akka.cluster.ddata.LWWRegisterKey;
  19 import akka.cluster.ddata.typed.javadsl.DistributedData;
  20 import akka.cluster.ddata.typed.javadsl.Replicator.Get;
  21 import akka.cluster.ddata.typed.javadsl.Replicator.GetFailure;
  22 import akka.cluster.ddata.typed.javadsl.Replicator.GetResponse;
  23 import akka.cluster.ddata.typed.javadsl.Replicator.GetSuccess;
  24 import akka.cluster.ddata.typed.javadsl.Replicator.NotFound;
  25 import akka.cluster.ddata.typed.javadsl.Replicator.ReadMajority;
  26 import akka.cluster.ddata.typed.javadsl.ReplicatorMessageAdapter;
  27 import java.time.Duration;
  28 import org.opendaylight.controller.eos.akka.owner.checker.command.GetOwnershipState;
  29 import org.opendaylight.controller.eos.akka.owner.checker.command.GetOwnershipStateReply;
  30 import org.opendaylight.controller.eos.akka.owner.checker.command.InternalGetReply;
  31 import org.opendaylight.controller.eos.akka.owner.checker.command.StateCheckerCommand;
  32 import org.opendaylight.mdsal.eos.common.api.EntityOwnershipState;
  33 import org.slf4j.Logger;
  34 import org.slf4j.LoggerFactory;
  35
  36 public final class OwnerStateChecker extends AbstractBehavior<StateCheckerCommand> {
  37     private static final Logger LOG = LoggerFactory.getLogger(OwnerStateChecker.class);
  38     private static final Duration GET_OWNERSHIP_TIMEOUT = Duration.ofSeconds(5);
  39     private static final Duration UNEXPECTED_ASK_TIMEOUT = Duration.ofSeconds(5);
  40
  41     private final ReplicatorMessageAdapter<StateCheckerCommand, LWWRegister<String>> replicatorAdapter;
  42     private final String localMember;
  43
  44     private OwnerStateChecker(final ActorContext<StateCheckerCommand> context, final String localMember) {
  45         super(context);
  46         this.localMember = requireNonNull(localMember);
  47         replicatorAdapter = new ReplicatorMessageAdapter<>(context,
  48             DistributedData.get(context.getSystem()).replicator(), UNEXPECTED_ASK_TIMEOUT);
  49     }
  50
  51     public static Behavior<StateCheckerCommand> create(final String localMember) {
  52         return Behaviors.setup(ctx -> new OwnerStateChecker(ctx, localMember));
  53     }
  54
  55     @Override
  56     public Receive<StateCheckerCommand> createReceive() {
  57         return newReceiveBuilder()
  58                 .onMessage(GetOwnershipState.class, this::onGetOwnershipState)
  59                 .onMessage(InternalGetReply.class, this::respondWithState)
  60                 .build();
  61     }
  62
  63     private Behavior<StateCheckerCommand> onGetOwnershipState(final GetOwnershipState message) {
  64         replicatorAdapter.askGet(
  65                 askReplyTo -> new Get<>(
  66                         new LWWRegisterKey<>(message.getEntity().toString()),
  67                         new ReadMajority(GET_OWNERSHIP_TIMEOUT),
  68                         askReplyTo),
  69                 reply -> new InternalGetReply(reply, message.getEntity(), message.getReplyTo()));
  70         return this;
  71     }
  72
  73     private Behavior<StateCheckerCommand> respondWithState(final InternalGetReply reply) {
  74         final GetResponse<LWWRegister<String>> response = reply.getResponse();
  75         if (response instanceof NotFound) {
  76             LOG.debug("Data for owner not found, most likely no owner has beed picked for entity: {}",
  77                     reply.getEntity());
  78             reply.getReplyTo().tell(new GetOwnershipStateReply(null));
  79         } else if (response instanceof GetFailure) {
  80             LOG.warn("Failure retrieving data for entity: {}", reply.getEntity());
  81             reply.getReplyTo().tell(new GetOwnershipStateReply(null));
  82         } else if (response instanceof GetSuccess) {
  83             final String owner = ((GetSuccess<LWWRegister<String>>) response).get(response.key()).getValue();
  84             LOG.debug("Data for owner received. {}, owner: {}", response, owner);
  85
  86             final boolean isOwner = localMember.equals(owner);
  87             final boolean hasOwner = !owner.isEmpty();
  88
  89             reply.getReplyTo().tell(new GetOwnershipStateReply(EntityOwnershipState.from(isOwner, hasOwner)));
  90         }
  91         return this;
  92     }
  93 }