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 java.io.IOException;
  12 import java.io.ObjectInputStream;
  13 import java.io.ObjectOutputStream;
  14 import java.util.ArrayList;
  15 import java.util.List;
  16 import org.opendaylight.controller.cluster.raft.RaftVersions;
  17 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  18
  19 /**
  20  * Invoked by leader to replicate log entries (§5.3); also used as
  21  * heartbeat (§5.2).
  22  */
  23 public class AppendEntries extends AbstractRaftRPC {
  24     private static final long serialVersionUID = 1L;
  25
  26     private static final org.slf4j.Logger LOG = org.slf4j.LoggerFactory.getLogger(AppendEntries.class);
  27
  28     // So that follower can redirect clients
  29     private final String leaderId;
  30
  31     // Index of log entry immediately preceding new ones
  32     private final long prevLogIndex;
  33
  34     // term of prevLogIndex entry
  35     private final long prevLogTerm;
  36
  37     // log entries to store (empty for heartbeat;
  38     // may send more than one for efficiency)
  39     private transient List<ReplicatedLogEntry> entries;
  40
  41     // leader's commitIndex
  42     private final long leaderCommit;
  43
  44     // index which has been replicated successfully to all followers, -1 if none
  45     private final long replicatedToAllIndex;
  46
  47     private final short payloadVersion;
  48
  49     public AppendEntries(long term, String leaderId, long prevLogIndex, long prevLogTerm,
  50             List<ReplicatedLogEntry> entries, long leaderCommit, long replicatedToAllIndex, short payloadVersion) {
  51         super(term);
  52         this.leaderId = leaderId;
  53         this.prevLogIndex = prevLogIndex;
  54         this.prevLogTerm = prevLogTerm;
  55         this.entries = entries;
  56         this.leaderCommit = leaderCommit;
  57         this.replicatedToAllIndex = replicatedToAllIndex;
  58         this.payloadVersion = payloadVersion;
  59     }
  60
  61     private void writeObject(ObjectOutputStream out) throws IOException {
  62         out.writeShort(RaftVersions.CURRENT_VERSION);
  63         out.defaultWriteObject();
  64
  65         out.writeInt(entries.size());
  66         for(ReplicatedLogEntry e: entries) {
  67             out.writeObject(e);
  68         }
  69     }
  70
  71     private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
  72         in.readShort(); // raft version
  73
  74         in.defaultReadObject();
  75
  76         int size = in.readInt();
  77         entries = new ArrayList<>(size);
  78         for(int i = 0; i < size; i++) {
  79             entries.add((ReplicatedLogEntry) in.readObject());
  80         }
  81     }
  82
  83     public String getLeaderId() {
  84         return leaderId;
  85     }
  86
  87     public long getPrevLogIndex() {
  88         return prevLogIndex;
  89     }
  90
  91     public long getPrevLogTerm() {
  92         return prevLogTerm;
  93     }
  94
  95     public List<ReplicatedLogEntry> getEntries() {
  96         return entries;
  97     }
  98
  99     public long getLeaderCommit() {
 100         return leaderCommit;
 101     }
 102
 103     public long getReplicatedToAllIndex() {
 104         return replicatedToAllIndex;
 105     }
 106
 107     public short getPayloadVersion() {
 108         return payloadVersion;
 109     }
 110
 111     @Override
 112     public String toString() {
 113         StringBuilder builder = new StringBuilder();
 114         builder.append("AppendEntries [leaderId=").append(leaderId).append(", prevLogIndex=").append(prevLogIndex)
 115                 .append(", prevLogTerm=").append(prevLogTerm).append(", leaderCommit=").append(leaderCommit)
 116                 .append(", replicatedToAllIndex=").append(replicatedToAllIndex).append(", payloadVersion=")
 117                 .append(payloadVersion).append(", entries=").append(entries).append("]");
 118         return builder.toString();
 119     }
 120 }