opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/messages/AppendEntries.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.raft.messages;
  10
  11 import com.google.protobuf.GeneratedMessage;
  12 import java.io.IOException;
  13 import java.io.ObjectInputStream;
  14 import java.io.ObjectOutputStream;
  15 import java.util.ArrayList;
  16 import java.util.Iterator;
  17 import java.util.List;
  18 import java.util.Map;
  19 import org.opendaylight.controller.cluster.raft.RaftVersions;
  20 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  21 import org.opendaylight.controller.cluster.raft.ReplicatedLogImplEntry;
  22 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  23 import org.opendaylight.controller.protobuff.messages.cluster.raft.AppendEntriesMessages;
  24
  25 /**
  26  * Invoked by leader to replicate log entries (§5.3); also used as
  27  * heartbeat (§5.2).
  28  */
  29 public class AppendEntries extends AbstractRaftRPC {
  30     private static final long serialVersionUID = 1L;
  31
  32     public static final Class<AppendEntriesMessages.AppendEntries> LEGACY_SERIALIZABLE_CLASS =
  33             AppendEntriesMessages.AppendEntries.class;
  34
  35     private static final org.slf4j.Logger LOG = org.slf4j.LoggerFactory.getLogger(AppendEntries.class);
  36
  37     // So that follower can redirect clients
  38     private final String leaderId;
  39
  40     // Index of log entry immediately preceding new ones
  41     private final long prevLogIndex;
  42
  43     // term of prevLogIndex entry
  44     private final long prevLogTerm;
  45
  46     // log entries to store (empty for heartbeat;
  47     // may send more than one for efficiency)
  48     private transient List<ReplicatedLogEntry> entries;
  49
  50     // leader's commitIndex
  51     private final long leaderCommit;
  52
  53     // index which has been replicated successfully to all followers, -1 if none
  54     private final long replicatedToAllIndex;
  55
  56     private final short payloadVersion;
  57
  58     public AppendEntries(long term, String leaderId, long prevLogIndex, long prevLogTerm,
  59             List<ReplicatedLogEntry> entries, long leaderCommit, long replicatedToAllIndex, short payloadVersion) {
  60         super(term);
  61         this.leaderId = leaderId;
  62         this.prevLogIndex = prevLogIndex;
  63         this.prevLogTerm = prevLogTerm;
  64         this.entries = entries;
  65         this.leaderCommit = leaderCommit;
  66         this.replicatedToAllIndex = replicatedToAllIndex;
  67         this.payloadVersion = payloadVersion;
  68     }
  69
  70     private void writeObject(ObjectOutputStream out) throws IOException {
  71         out.writeShort(RaftVersions.CURRENT_VERSION);
  72         out.defaultWriteObject();
  73
  74         out.writeInt(entries.size());
  75         for(ReplicatedLogEntry e: entries) {
  76             out.writeObject(e);
  77         }
  78     }
  79
  80     private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
  81         in.readShort(); // raft version
  82
  83         in.defaultReadObject();
  84
  85         int size = in.readInt();
  86         entries = new ArrayList<>(size);
  87         for(int i = 0; i < size; i++) {
  88             entries.add((ReplicatedLogEntry) in.readObject());
  89         }
  90     }
  91
  92     public String getLeaderId() {
  93         return leaderId;
  94     }
  95
  96     public long getPrevLogIndex() {
  97         return prevLogIndex;
  98     }
  99
 100     public long getPrevLogTerm() {
 101         return prevLogTerm;
 102     }
 103
 104     public List<ReplicatedLogEntry> getEntries() {
 105         return entries;
 106     }
 107
 108     public long getLeaderCommit() {
 109         return leaderCommit;
 110     }
 111
 112     public long getReplicatedToAllIndex() {
 113         return replicatedToAllIndex;
 114     }
 115
 116     public short getPayloadVersion() {
 117         return payloadVersion;
 118     }
 119
 120     @Override
 121     public String toString() {
 122         StringBuilder builder = new StringBuilder();
 123         builder.append("AppendEntries [leaderId=").append(leaderId).append(", prevLogIndex=").append(prevLogIndex)
 124                 .append(", prevLogTerm=").append(prevLogTerm).append(", leaderCommit=").append(leaderCommit)
 125                 .append(", replicatedToAllIndex=").append(replicatedToAllIndex).append(", payloadVersion=")
 126                 .append(payloadVersion).append(", entries=").append(entries).append("]");
 127         return builder.toString();
 128     }
 129
 130     public <T extends Object> Object toSerializable() {
 131         return toSerializable(RaftVersions.CURRENT_VERSION);
 132     }
 133
 134     public <T extends Object> Object toSerializable(short version) {
 135         if(version < RaftVersions.LITHIUM_VERSION) {
 136             return toLegacySerializable();
 137         } else {
 138             return this;
 139         }
 140     }
 141
 142     @SuppressWarnings({ "rawtypes", "unchecked" })
 143     private <T> Object toLegacySerializable() {
 144         AppendEntriesMessages.AppendEntries.Builder to = AppendEntriesMessages.AppendEntries.newBuilder();
 145         to.setTerm(this.getTerm())
 146             .setLeaderId(this.getLeaderId())
 147             .setPrevLogTerm(this.getPrevLogTerm())
 148             .setPrevLogIndex(this.getPrevLogIndex())
 149             .setLeaderCommit(this.getLeaderCommit());
 150
 151         for (ReplicatedLogEntry logEntry : this.getEntries()) {
 152
 153             AppendEntriesMessages.AppendEntries.ReplicatedLogEntry.Builder arBuilder =
 154                 AppendEntriesMessages.AppendEntries.ReplicatedLogEntry.newBuilder();
 155
 156             AppendEntriesMessages.AppendEntries.ReplicatedLogEntry.Payload.Builder arpBuilder =
 157                 AppendEntriesMessages.AppendEntries.ReplicatedLogEntry.Payload.newBuilder();
 158
 159             //get the client specific payload extensions and add them to the payload builder
 160             Map<GeneratedMessage.GeneratedExtension, T> map = logEntry.getData().encode();
 161             Iterator<Map.Entry<GeneratedMessage.GeneratedExtension, T>> iter = map.entrySet().iterator();
 162
 163             while (iter.hasNext()) {
 164                 Map.Entry<GeneratedMessage.GeneratedExtension, T> entry = iter.next();
 165                 arpBuilder.setExtension(entry.getKey(), entry.getValue());
 166             }
 167
 168             arpBuilder.setClientPayloadClassName(logEntry.getData().getClientPayloadClassName());
 169
 170             arBuilder.setData(arpBuilder).setIndex(logEntry.getIndex()).setTerm(logEntry.getTerm());
 171             to.addLogEntries(arBuilder);
 172         }
 173
 174         return to.build();
 175     }
 176
 177     public static AppendEntries fromSerializable(Object serialized) {
 178         if(serialized instanceof AppendEntries) {
 179             return (AppendEntries)serialized;
 180         }
 181         else {
 182             return fromLegacySerializable((AppendEntriesMessages.AppendEntries) serialized);
 183         }
 184     }
 185
 186     private static AppendEntries fromLegacySerializable(AppendEntriesMessages.AppendEntries from) {
 187         List<ReplicatedLogEntry> logEntryList = new ArrayList<>();
 188         for (AppendEntriesMessages.AppendEntries.ReplicatedLogEntry leProtoBuff : from.getLogEntriesList()) {
 189
 190             Payload payload = null ;
 191             try {
 192                 if(leProtoBuff.getData() != null && leProtoBuff.getData().getClientPayloadClassName() != null) {
 193                     String clientPayloadClassName = leProtoBuff.getData().getClientPayloadClassName();
 194                     payload = (Payload) Class.forName(clientPayloadClassName).newInstance();
 195                     payload = payload.decode(leProtoBuff.getData());
 196                 } else {
 197                     LOG.error("Payload is null or payload does not have client payload class name");
 198                 }
 199
 200             } catch (InstantiationException e) {
 201                 LOG.error("InstantiationException when instantiating "+leProtoBuff.getData().getClientPayloadClassName(), e);
 202             } catch (IllegalAccessException e) {
 203                 LOG.error("IllegalAccessException when accessing "+leProtoBuff.getData().getClientPayloadClassName(), e);
 204             } catch (ClassNotFoundException e) {
 205                 LOG.error("ClassNotFoundException when loading "+leProtoBuff.getData().getClientPayloadClassName(), e);
 206             }
 207             ReplicatedLogEntry logEntry = new ReplicatedLogImplEntry(
 208                 leProtoBuff.getIndex(), leProtoBuff.getTerm(), payload);
 209             logEntryList.add(logEntry);
 210         }
 211
 212         AppendEntries to = new AppendEntries(from.getTerm(),
 213             from.getLeaderId(),
 214             from.getPrevLogIndex(),
 215             from.getPrevLogTerm(),
 216             logEntryList,
 217             from.getLeaderCommit(), -1, (short)0);
 218
 219         return to;
 220     }
 221
 222     public static boolean isSerializedType(Object message) {
 223         return message instanceof AppendEntries || LEGACY_SERIALIZABLE_CLASS.isInstance(message);
 224     }
 225 }