opendaylight/md-sal/sal-akka-raft-example/src/main/java/org/opendaylight/controller/cluster/example/ExampleActor.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. 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
   9 package org.opendaylight.controller.cluster.example;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.Props;
  13 import com.google.common.base.Optional;
  14 import com.google.protobuf.ByteString;
  15 import java.io.ByteArrayInputStream;
  16 import java.io.ByteArrayOutputStream;
  17 import java.io.IOException;
  18 import java.io.ObjectInputStream;
  19 import java.io.ObjectOutputStream;
  20 import java.util.HashMap;
  21 import java.util.Map;
  22 import javax.annotation.Nonnull;
  23 import org.opendaylight.controller.cluster.example.messages.KeyValue;
  24 import org.opendaylight.controller.cluster.example.messages.KeyValueSaved;
  25 import org.opendaylight.controller.cluster.example.messages.PrintRole;
  26 import org.opendaylight.controller.cluster.example.messages.PrintState;
  27 import org.opendaylight.controller.cluster.notifications.RoleChangeNotifier;
  28 import org.opendaylight.controller.cluster.raft.ConfigParams;
  29 import org.opendaylight.controller.cluster.raft.RaftActor;
  30 import org.opendaylight.controller.cluster.raft.RaftActorRecoveryCohort;
  31 import org.opendaylight.controller.cluster.raft.RaftActorSnapshotCohort;
  32 import org.opendaylight.controller.cluster.raft.RaftState;
  33 import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshotReply;
  34 import org.opendaylight.controller.cluster.raft.behaviors.Leader;
  35 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  36 import org.opendaylight.yangtools.concepts.Identifier;
  37 import org.opendaylight.yangtools.util.StringIdentifier;
  38
  39 /**
  40  * A sample actor showing how the RaftActor is to be extended
  41  */
  42 public class ExampleActor extends RaftActor implements RaftActorRecoveryCohort, RaftActorSnapshotCohort {
  43
  44     private final Map<String, String> state = new HashMap<>();
  45
  46     private long persistIdentifier = 1;
  47     private final Optional<ActorRef> roleChangeNotifier;
  48
  49
  50     public ExampleActor(String id, Map<String, String> peerAddresses,
  51         Optional<ConfigParams> configParams) {
  52         super(id, peerAddresses, configParams, (short)0);
  53         setPersistence(true);
  54         roleChangeNotifier = createRoleChangeNotifier(id);
  55     }
  56
  57     public static Props props(final String id, final Map<String, String> peerAddresses,
  58             final Optional<ConfigParams> configParams) {
  59         return Props.create(ExampleActor.class, id, peerAddresses, configParams);
  60     }
  61
  62     @Override
  63     protected void handleNonRaftCommand(Object message) {
  64         if(message instanceof KeyValue){
  65             if(isLeader()) {
  66                 persistData(getSender(), new StringIdentifier(String.valueOf(persistIdentifier++)), (Payload) message);
  67             } else {
  68                 if(getLeader() != null) {
  69                     getLeader().forward(message, getContext());
  70                 }
  71             }
  72
  73         } else if (message instanceof PrintState) {
  74             if(LOG.isDebugEnabled()) {
  75                 LOG.debug("State of the node:{} has entries={}, {}",
  76                     getId(), state.size(), getReplicatedLogState());
  77             }
  78
  79         } else if (message instanceof PrintRole) {
  80             if(LOG.isDebugEnabled()) {
  81                 if (getRaftState() == RaftState.Leader || getRaftState() == RaftState.IsolatedLeader) {
  82                     final String followers = ((Leader)this.getCurrentBehavior()).printFollowerStates();
  83                     LOG.debug("{} = {}, Peers={}, followers={}", getId(), getRaftState(),
  84                         getRaftActorContext().getPeerIds(), followers);
  85                 } else {
  86                     LOG.debug("{} = {}, Peers={}", getId(), getRaftState(),
  87                         getRaftActorContext().getPeerIds());
  88                 }
  89
  90
  91             }
  92
  93         } else {
  94             super.handleNonRaftCommand(message);
  95         }
  96     }
  97
  98     protected String getReplicatedLogState() {
  99         return "snapshotIndex=" + getRaftActorContext().getReplicatedLog().getSnapshotIndex()
 100             + ", snapshotTerm=" + getRaftActorContext().getReplicatedLog().getSnapshotTerm()
 101             + ", im-mem journal size=" + getRaftActorContext().getReplicatedLog().size();
 102     }
 103
 104     public Optional<ActorRef> createRoleChangeNotifier(String actorId) {
 105         ActorRef exampleRoleChangeNotifier = this.getContext().actorOf(
 106             RoleChangeNotifier.getProps(actorId), actorId + "-notifier");
 107         return Optional.<ActorRef>of(exampleRoleChangeNotifier);
 108     }
 109
 110     @Override
 111     protected Optional<ActorRef> getRoleChangeNotifier() {
 112         return roleChangeNotifier;
 113     }
 114
 115     @Override
 116     protected void applyState(final ActorRef clientActor, final Identifier identifier, final Object data) {
 117         if(data instanceof KeyValue){
 118             KeyValue kv = (KeyValue) data;
 119             state.put(kv.getKey(), kv.getValue());
 120             if(clientActor != null) {
 121                 clientActor.tell(new KeyValueSaved(), getSelf());
 122             }
 123         }
 124     }
 125
 126     @Override
 127     public void createSnapshot(ActorRef actorRef) {
 128         ByteString bs = null;
 129         try {
 130             bs = fromObject(state);
 131         } catch (Exception e) {
 132             LOG.error("Exception in creating snapshot", e);
 133         }
 134         getSelf().tell(new CaptureSnapshotReply(bs.toByteArray()), null);
 135     }
 136
 137     @Override
 138     public void applySnapshot(byte [] snapshot) {
 139         state.clear();
 140         try {
 141             state.putAll((HashMap<String, String>) toObject(snapshot));
 142         } catch (Exception e) {
 143            LOG.error("Exception in applying snapshot", e);
 144         }
 145         if(LOG.isDebugEnabled()) {
 146             LOG.debug("Snapshot applied to state : {}", ((HashMap<?, ?>) state).size());
 147         }
 148     }
 149
 150     private static ByteString fromObject(Object snapshot) throws Exception {
 151         ByteArrayOutputStream b = null;
 152         ObjectOutputStream o = null;
 153         try {
 154             b = new ByteArrayOutputStream();
 155             o = new ObjectOutputStream(b);
 156             o.writeObject(snapshot);
 157             byte[] snapshotBytes = b.toByteArray();
 158             return ByteString.copyFrom(snapshotBytes);
 159         } finally {
 160             if (o != null) {
 161                 o.flush();
 162                 o.close();
 163             }
 164             if (b != null) {
 165                 b.close();
 166             }
 167         }
 168     }
 169
 170     private static Object toObject(byte [] bs) throws ClassNotFoundException, IOException {
 171         Object obj = null;
 172         ByteArrayInputStream bis = null;
 173         ObjectInputStream ois = null;
 174         try {
 175             bis = new ByteArrayInputStream(bs);
 176             ois = new ObjectInputStream(bis);
 177             obj = ois.readObject();
 178         } finally {
 179             if (bis != null) {
 180                 bis.close();
 181             }
 182             if (ois != null) {
 183                 ois.close();
 184             }
 185         }
 186         return obj;
 187     }
 188
 189     @Override protected void onStateChanged() {
 190
 191     }
 192
 193     @Override public String persistenceId() {
 194         return getId();
 195     }
 196
 197     @Override
 198     @Nonnull
 199     protected RaftActorRecoveryCohort getRaftActorRecoveryCohort() {
 200         return this;
 201     }
 202
 203     @Override
 204     public void startLogRecoveryBatch(int maxBatchSize) {
 205     }
 206
 207     @Override
 208     public void appendRecoveredLogEntry(Payload data) {
 209     }
 210
 211     @Override
 212     public void applyCurrentLogRecoveryBatch() {
 213     }
 214
 215     @Override
 216     public void onRecoveryComplete() {
 217     }
 218
 219     @Override
 220     public void applyRecoverySnapshot(byte[] snapshot) {
 221     }
 222
 223     @Override
 224     protected RaftActorSnapshotCohort getRaftActorSnapshotCohort() {
 225         return this;
 226     }
 227
 228     @Override
 229     public byte[] getRestoreFromSnapshot() {
 230         return null;
 231     }
 232 }